What is known about the experiences of using CPAP for OSA from the users' perspective? A systematic integrative literature review

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Sleep Medicine Reviews xxx (2014) 1e10

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Sleep Medicine Reviews

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CLINICAL REVIEW

What is known about the experiences of using CPAP for OSA from theusers’ perspective? A systematic integrative literature review

Kim Ward*, Karen J. Hoare, Merryn GottThe University of Auckland, New Zealand

a r t i c l e i n f o

Article history:Received 2 July 2013Received in revised form8 January 2014Accepted 9 January 2014Available online xxx

Keywords:Continuous positive airway pressureNasal CPAPObstructive sleep apnoeaHypopnoeaPatient experiencesIntegrative review

* Corresponding author. School of Nursing, FacultyThe University of Auckland, 85 Park Road, GraftoTel.: þ64 99232265; fax: þ64 93677158.

E-mail address: [email protected] (K. Ward).

1087-0792/$ e see front matter � 2014 Elsevier Ltd.http://dx.doi.org/10.1016/j.smrv.2014.01.001

Please cite this article in press as: Ward K, esystematic integrative literature review, Sle

s u m m a r y

Economic, social and personal costs of untreated obstructive sleep apnoea (OSA) are high. Continuouspositive airway pressure (CPAP) is recommended and cost effective. Increasing OSA prevalence mayaccompany predicted globally increasing obesity.Objective: To synthesise international evidence regarding personal experiences using CPAP for OSA.Methods: A systematic integrative literature review was conducted and quality assessment criteriaapplied.Results: 22, of 538, identified papers met inclusion criteria. Thematic analysis identified three themes: 1)users’ beliefs about CPAP influence users’ experiences of CPAP; 2) CPAP users are primed to reflectnegatively on experiences of CPAP; and 3) spouse and family influence users’ experiences of CPAP.Personality and attitude impact expectations about CPAP prior to use, whilst engagement of spouse andfamily also influence experiences. Analysis highlighted that users’ reporting of CPAP experiences isconstrained by investigator defined assessment methods. Overall, research relating to experiences usingCPAP is limited.Conclusion: Users’ perspectives of CPAP are constrained by researchers’ concern with non-compliance.Typically experiences are not defined by the user, but from an ‘expert’ healthcare perspective, usingwords which frame CPAP as problematic. Family and social support is a significant, but neglected area ofexperiencing CPAP warranting further investigation. More information from users is required to deter-mine how CPAP can be managed successfully.

� 2014 Elsevier Ltd. All rights reserved.

Introduction

Obstructive sleep apnoea (OSA) is a chronic syndrome thatcarries both personal and societal costs [1,2]. In OSA collapsibility ofthe upper airway during sleep leads to repeated momentarycessation of breathing of anywhere between five to over 100 timesper hour resulting in decreased blood oxygen saturation [3]. Thisleads to repeated arousals and associated symptoms such as snor-ing and hypersomnolence [3,4]. The resultant reduction in qualityof life has negative impacts on relationships, home and social life[5e7].

The estimated economic and social cost of OSA is high [8,9]. OSAhas a strong association with obesity [10e12], and is implicated asan independent risk factor for hypertension and cardiac sequelae[13e17]. People with untreated OSA are also likely to experience

of Medical & Health Sciences,n, Auckland, New Zealand.

All rights reserved.

t al., What is known about thep Medicine Reviews (2014),

occupational and vehicular accidents more frequently than thegeneral population [18e20]. Canadian and United States (US)medical costs for OSA patients prior to diagnosis were roughly two-fold the cost for people without OSA, with an estimated US$15.9billion spent in 2006 [21e24].

In population based epidemiologic studies even mild sleepapnoea has been associated with significant morbidity [10,25].Global studies indicate the prevalence of OSA syndrome (apnoeahypopnoea index [AHI] �5 events/h plus daytime sleepiness) isbetween 3% and 7% [4,26]. Additional evidence indicates that one infive overweight US adults have at least mild sleep apnoea(AHI � five events/h) [25]. Under-diagnosis in the general popula-tion is also of growing concern [4,10].

Night-time continuous positive airway pressure (CPAP) via nasalor face mask is a recommended, effective and popular treatmentoption for OSA [27e29]. CPAP applied via a face or nasal mask actsas a pneumatic splint holding the pharynx open during sleep. Theprimary purpose is relief of respiratory dysfunction so decreasingworkload on the heart plus secondary relief of daytime sleepinessand attendant sequelae [28,30,31]. However, CPAP can be painful

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Table 2Search terms.

‘Continuous positiveairway pressure’

‘Obstructive sleepapnoea’

‘Patients’ experience’

Continuous positiveairway pressure (CPAP)Nasal continuous positiveairway pressure (NCPAP)

Sleep apn?ea*Obstructive sleepapn* (OSA)Sleep apn?easyndrome (OSAS)Hypopn?ea

Experience*Perspective*Perception*Attitude*Adapt*Coping behaviourCoping Cope*Living Live*Self-efficacyPoint of view* Opinion*Symptom distress

Key: * Alternate endings applied during search; ? Alternate spelling applied duringsearch.

Abbreviations:

AHI apnoea hypopnoea indexBMI body mass indexCPAP continuous positive airway pressureCASP critical appraisal skills programmeHBM health beliefs modelOSA obstructive sleep apnoeaRDI respiratory disturbance indexSECI side effects of CPAP inventory

K. Ward et al. / Sleep Medicine Reviews xxx (2014) 1e102

around the face, may wake the user during sleep, and has associ-ated side effects [32,33]. Despite empirical evidence generated overthe last three decades, that OSA is a health risk and CPAP is aneffective and recommended treatment, studies suggest that poorcompliance with this therapy remains a concern [34,35].

Internationally CPAP as a treatment for OSA is considered costeffective and after 13 y of use becomes cost saving [23,36]. TheWorld Health Organisation suggests that 65e75% of people withOSA are obese (body mass index [BMI] �30.0 kg/m2) [37]. The pre-dicted global increase in obesity will therefore lead to an increase inprevalence of OSA. Exploring management of CPAP from the userperspective is crucial to successful administration of therapy. Thismanuscript identifies and synthesises international evidence aboutusers’ personal experiences of using CPAP. For the purposes of thisreview ‘experience of CPAP’ is defined as personal perceptions,opinions or knowledge gained from personal use of CPAP for OSA.

Methods

An integrative review was conducted and all studies that exam-ined the experiences of using night-time CPAP for OSA wereincluded. An integrative review provides a systematic approach toexamining studies that have adopted diverse methodologies [38].This approach provides a comprehensive exploration of a particularphenomenon or healthcare problem by drawing on a wide range ofevidence rather thanmaintaininga focuson theclinical trial [39e41].

Search strategy

The following search strategy was used in the online databasesMedline, PsycINFO, the cumulative index to nursing and alliedhealth literature (CINAHL Plus), Cochrane and Web of Science(including social sciences citation index plus expanded). Pre-determined inclusion and exclusion criteria were applied (Table 1).

Searches were carried out via title, subject and keyword. Searchterms were designed to capture variants of the terms ‘continuous

Table 1Review inclusion and exclusion criteria.

Inclusion Exclusion

Papers focusing on anyelement of adult patients’personal experiencesa

of using CPAP for OSA

Not including any element of the patients’personal experiences of using CPAP for OSA

Papers focusing on CPAP for reasonsother than OSA

English language Not English languageParticipants aged 18þ inclusive Papers focusing on children (up to age 18)Empirical studies Non empirical studies, theoretical,

discussion papers or dissertationsPapers from Jan 1990

to Sept 2012Papers prior to 1990

Key: CPAP: continuous positive airway pressure; OSA: obstructive sleep apnoea.a Report of patients’ personal experiences included their own words or theirresponse to a choice of predetermined constructs.

Please cite this article in press as: Ward K, et al., What is known about tsystematic integrative literature review, Sleep Medicine Reviews (2014),

positive airway pressure’, ‘obstructive sleep apnoea’, and ‘patients’experience’with appropriate wildcards inserted to search for wordtruncations (See Table 2).

Search outcome

538 studies were identified during the initial search. The studyselection and inclusion process included tiered screening foreligibility via title, abstract and then full text (See Fig. 1).

Cross checking of rejected articles was carried out indepen-dently by KW and MG with consensus reached where ambiguityexisted. Reference tracking yielded an additional 19 articles forscreening, five of which contributed to the total 22 papers includedin this review (See Table 3).

Data extraction

Data extraction was performed using a standard pro forma [63],capturing relevance of each paper to the review, focus of the studydesign and study limitations. Both quantitative and qualitative datarelating to patient personal experiences, along with demographicdetails of the patient sample were extracted from each includedstudy (See Table 3).

Data evaluation

Study quality was assessed [64,65]. No gold standard forquality scoring in integrative reviews currently exists [66].

Fig. 1. Flowchart showing literature selection.

he experiences of using CPAP for OSA from the users’ perspective? Ahttp://dx.doi.org/10.1016/j.smrv.2014.01.001

Table 3Evidence on experiences of using CPAP for OSA.

Author/year, country/quality

Study design Setting and samplea Focus and outcomes of each studyb Data related to personal experiences of using CPAP

Aloia et al., 2007 [42]USAQuality Good

QuantitativeProspective observationalreplication study e participantsblinded

Teaching hospital, purposive sample140 (93 men)Age 25e77 yAHI 17e71/hCPAP use one night

Focus was on predicting six-month adherence to CPAPwithin the first days of CPAP use.Patterns of adherence were reported as highly variablenight-to-night and established within the first week oftreatment. Statistically significant side effects reportedincluded discomfort (p < 0.02), congestion (p < 0.05), andfeeling closed in (p< 0.03). Mask typewas not controlled foror measured so may have influenced adherence.

Participants that identified physical and social sideeffects of CPAP via a checklist of ‘most common’were limited to those experiencing problems.Checklist side effects were predetermined andderived using literature and expert opinion alone.

Ayow et al., 2009 [43]CanadaQuality Fair

QualitativeProspective descriptivecomparative case study e semi-structured interviews

Urban multisite sleep clinic, purposivesample8 (4 men)Age 38e58 yAHI 3e83/h, non-users (n ¼ 4) 31e59/hCPAP use 1e14 mo, 6e8 h/n, non-users4e52 mo

Facilitators and barriers to CPAP use were identified bycomparing CPAP users’ perspectives with non-users.Factors influencing use/non-use were physical,psychological, financial, and social comparison and stigmaas seen from opposing perspectives depending on case.Social and family structures were not exploredN andtheoretical saturation did not occur.

Exploration of experiences using CPAP wasrestricted to the influence of their experiences onadherence.Factors observed included physical benefits versusfrustration with device versus social factors, such asfeeling ugly using CPAP and guilty for not usingCPAP.

Broström et al., 2007[44]

SwedenQuality Good

QuantitativeRetrospective cross-sectionaldescriptive e survey

Urban hospital CPAP clinic, purposivesample247 (203 men)Age 51e69.5 yAHI 30e98/hCPAP use 6e182 mo, type D 2.5e7 h/n,non-type D 4e8 h/n

Described prevalence of Type De personality in OSA patientstreated with CPAP for� six months and the association withself-reported side effects and adherence. Side effects wereassessed using side effect of CPAP inventory (SECI). [45]The 30% of participants categorised as type D personalityreported more side effects from CPAP, with higherfrequency (p < 0.05e0.01) and lower adherence, thanpatients without type D personality.

The experience of using CPAP was examined inrelation to frequency, magnitude and impact ofpredetermined side effects, and their influence onadherence in the Type D personality.SECI [45] was based on personal accounts of usingCPAP, the literature and expert opinion. [46]


SwedenQuality Fair

QualitativeProspective phenomeno-graphic e single case study

Urban hospital CPAP clinic, purposivesample1 (man) þ female partnerAge 33 yAHI 92/hCPAP use 6 mo, 5e5.5 h/n

During initial six-months of CPAP use perceptions of theCPAP user and partner were explored, by relating to fivedimensions of health, to elucidate reasons behindcompliance and non-compliance.The viewpoint of one person with severe OSA and morbidobesity (BMI 40 kg/m2) was reported. 17 structural aspectsfluctuated during the six month study in relation tostressors, social reactions and adaptation to increasecompliance.

An holistic in-depth perspective presented of onecouple’s experiences using CPAP in the context ofinfluence on adherence.Included was exploration of conceptions of healthand psychosocial aspects for patient and partner,transitions adapting to practical problems anddiscomfort. Frustration, fear and stigmatisationwere described.


SwedenQuality Good


Urban hospital CPAP clinic, purposivesampleProfessionals 105 (20 men) Age 36e54 yPatients 350 (230 men) Age 52e66 yAHI 10e98/hCPAP use 0e182 mo, 79% >4 h/n

Compared the perceptions among CPAP users againstperceptions of healthcare professionals regarding users’informational needs, CPAP side-effects (using SECI [45]) andeffect on adherence.Possibilities to learn were perceived as greater by CPAPusers than by professionals. Patients perceived less frequentside effects with a lower impact on adherence than didhealthcare professionals.

The experience of using CPAP was examined in thecontext of side effects impacting adherence.Most common side effects were reported as blockednose, mask leaks, dry throat, and uncomfortablemask pressure.


SwedenQuality Fair

QualitativeExploratoryRetrospective inductiveapproach e semi-structuredinterviews

Rural pulmonary clinic, purposivesample23 (13 men)Age 33e74 yAHI 30e94/hCPAP use 0.5e148 mo, 79% >4 h/n

CPAP users’ experiences of adherence to CPAP wereexplored by analysing and describing patients’ in-depthaccounts of using CPAP.Two themes emerged: ‘putative facilitators’ and ‘putativebarriers’. Facilitators included symptom avoidance,knowledge of health risk, and negative social consequences.Barriers included side effects, practical problems and poorpersonal or professional support.

Exploration of experiencing CPAP was focused onfactors impacting adherence. Self-belief and self-efficacy led to a positive attitude towards CPAP, aswell as the reverse. Fear of negative socialconsequences led to guilt. SECI [45] was developedfrom this study.


Sweden -Quality Good

QuantitativeRetrospective instrumentdevelopment & validation e

survey

Urban hospital CPAP clinics, purposivesample329 (263 men)Age 21e82 yAHI 10e92/hCPAP use 0.5e182 mo, h/n unreported

The side-effects to CPAP inventory (SECI) was developed tomeasure magnitude and frequency of side-effects andimpact on use. Variables of difficulty were sought to assistthose unlikely to adhere to CPAP.SECI measurement properties were reported as satisfactory,promising and able to discriminate between adherent andnon-adherent CPAP users.

Expression of experiences using CPAP wasrestricted to a list of 15 pre-determined side-effects.The 15 side-effects were assembled on the basis ofin-depth interviews with 23 CPAP users [46],review of the scientific literature and consensus of amulti-professional expert panel.

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Table 3 (continued )

Author/year, country/quality

Study design Setting and samplea Focus and outcomes of each studyb Data related to personal experiences of using CPAP

Dickerson & Kennedy2006 [49]

USAQuality Fair

QualitativeRetrospective Heideggerianphenomenology e semi-structured interviews

Urban medical centre & rural hospital,purposive convenience sample17 (12 men)Age 40e73 yAHI unreportedCPAP use 1e84 mo, 3e11 h/n

Help-seeking experiences in support group attendees wereexplored to understand patients’ experiences anddifficulties using CPAP.Four themes emerged: (1) becoming motivated to persistwith help from the group, (2) accommodating to the device,(3) listening and telling stories to gain practical knowledge,and (4) implementing a support group as a caringcommunity.

Exploration of experiences using CPAP wasrestricted to the influence of user support groupparticipation on motivation to use CPAP.Experiences of using CPAP were described withintheme (2), these were struggling to persistaccommodating to an uncomfortable therapy andtrading exhaustion for the discomfort of CPAP.

Dickerson & Akhu-Zaheya 2007 [50]

USAQuality Good

QualitativeRetrospective Heideggerianhermeneutic phenomenologyplus pilot of Calgary OSA QOLtool e semi-structuredinterviews

Urban sleep centre, purposive sample20 (9 men)Age 31e72 yAHI unreportedCPAP use 0e3 mo, 6e8 h/n, non-users(n ¼ 4) duration unreported

Accommodation to nasal CPAP and motivation to use wasexplored during three months post CPAP initiation.Five themes emerged: (1) trouble using CPAP, (2) persistingthrough initial and recurring frustration, (3) difficultyrecognising subtle improvements, (4) accessing help andproblem solving, (5) becoming part of the routine orabandoning CPAP. Perseverance through tribulations bydeveloping a positivemind-set was the constitutive pattern.

The meaning CPAP users’made of their experienceswas explored to understand motivation to complywith treatment.Difficulties encountered using CPAP as time passedby both users and non-users were described. Theexperience of using CPAP became routine, or wasotherwise abandoned.

Engleman et al., 1996[51]

ScotlandQuality Poor


Scottish National Sleep Laboratory,purposive sample204 (187 men)Age 43e63 yAHI 9e85/hCPAP use 0.5e97 mo, 3.8e7.8 h/n e

self-report, 2.6e7.6 h/n e measured

Daytime function, nocturnal symptoms and road trafficincident (RTI) rate were assessed before and after CPAPinitiation to examine perceived benefit of CPAP and identifydeterminants of CPAP use.Excessive sleepiness and RTIs reduced by CPAP. Greater self-reported CPAP use was associated with better resolution ofsleepiness (p < 0.0001) and greater improvement indaytime function and nocturnal symptoms.

A minor part of the survey examined experiencesusing CPAP via a 12 item problem list, assessed on afour point scale, and limited to those experiencingproblems. Focus was on function, in-particulardriving competence.Source of the 12 items not reported.

Galetke et al., 2011 [52]GermanyQuality Good

QuantitativeRetrospective double blindcross-sectional e phone survey

Sleep laboratory, purposive sample303 (234 men)Age 46.5e70.5 yAHI 8e58/hCPAP use 12 mo, 5.1e8.1 h/n e self-report, 2.4e7 h/n e measured, 83 non-users

CPAP adherence was analysed with a focus on reasons forabandonment.‘Most’ patients (27%) who stopped treatment reportedmaskside effects and discomfort from the device and 17% becamenon-users due to lack of symptoms pre-initiation. Non-users were likely to be moderately obese women with mildOSA. Findings emphasised that the pattern of adherencebecame established in first 3e6 mo of use.

Assessment of patient experiences using CPAP wasrestricted to comfort of treatment andpredetermined side effects of treatment using ananalogue scale.Side effects and source not reported.

Hoffstein et al., 1992[53]

CanadaQuality Fair

QuantitativeCross-sectional descriptive e

survey

Sleep clinic, purposive sample96 (gender not given)Age 37e62 yAHI 11e153/hCPAP use 0e28 mo, 1e8 h/n

Factors influencing acceptance of nasal CPAP were analysedincluding perceived beneficial effects, equipment problems,side effects and suggestions for improvement. Ontariopatient cohort was compared with other populations.81% of respondents believed CPAP was effective forsubjective complaints. Non-compliant (those who stoppedCPAP) respondents (18%) perceived no beneficial effects,made more adverse comments about CPAP and theirfamilies noticed no improvement.

Assessment of patient experiences using CPAP wasrestricted to two of eight yes/no questions.A choice of answers to questions was offered, butnot reported: predetermined side effects werereported as based on common complaints andcomments voiced by other clinic patients.

Holmdahl et al., 2009[54]

SwedenQuality Good

QuantitativeProspective e RCT

University hospital, purposive sample200 (189 men)Age 29e79 yAHI >15/h (no range)CPAP use 1e144 mo, 4e6þ h/n

Nurse specialist-led follow-up visits (intervention) werecompared with physician-led visits (control) for stable CPAPpatients. Patient satisfaction, quality of life, medical eventsand health resource utilisation were assessed.Nurse specialist follow-up optimised the use of healthresources while retaining patient satisfaction with follow-up without increasing medical risks. Women were absentfrom the intervention group.N

Assessment of patient experiences using CPAP wasrestricted to two open questions about the mostpositive aspect of CPAP (reduced tiredness) and themost negative aspect of CPAP (dependence on theCPAP device and mask problems e 50% responserate). 99% of participants rated the overallexperience of CPAP as good or excellent.

Meslier et al., 1998 [55]FranceQuality Good


French respiratory homecare network,purposive sample3225 (2796 men)Age 48e70 yAHI unreportedCPAP use 6e48þ mo, 1e9 h/n

CPAP users’ perceptions of benefits from CPAP, quality oflife, CPAP tolerance and compliance were investigated.80% of sample had improved symptoms despite discomfortfrom CPAP device: 52.2% reported dry mouth and throat,47% blower noise disturbing bed partner. 57% of samplerated nasal mask tolerance as good/very good. Overallsatisfaction with CPAP was good/very good (90%) whichcorrelated with self-reported compliance (p < 0.01).

Assessment of patient experiences using CPAP wasrestricted to pre-determined side effects list toexamine CPAP tolerance and their influence oncompliance. Source of side effects not reported.Participants appeared satisfied with therapy despiteside effects.

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Moroni et al., 2011 [56]ItalyQuality Good

QuantitativeProspective e tool validation

Setting not specified, purposive sample96 (78 men) Participants who stoppedCPAP (n ¼ 29) were not re-surveyed.Reason unreported.N

Age 18e78 yAHI 10e96/hCPAP use 0e6 mo, h/n unreported

Maugeri OSA syndrome questionnaire (MOSAS) wasdeveloped and validated to assess psychological andphysical impact of OSA and to determine risk for non-adherence to CPAP.Good statistical quality of MOSAS reported. CPAP use of<4 h/n led to higher median scores for psychological impactof OSA, whilst greater CPAP discomfort and nuisance led toreduced CPAP use (p < 0.01).

Assessment of patient experiences using CPAP wasrestricted to the seven item assessment of“discomfort and nuisance of CPAP”, section B ofMOSAS, which focused on ability to use CPAP anddifficulties with the CPAP device.

Pépin et al., 1995 [32]FranceQuality Fair

QuantitativeProspective cross-sectionalcomparative e survey

Setting not specified, purposive sample193 (165 men)Age 41e71 yRDIc 28e78/hCPAP use 2e36 mo, 5.4e9.4 h/n e self-report, 3.5e9.5 h/n e measured

Subjective benefits and side effects of nasal CPAP wereexamined including compliance at six month intervals.Side effects reported were mainly local to the nose, with50% of patients reporting at least one side effect. GreaterOSA severity led to greater perceived benefit from CPAP.Compliance was high at mean 6.5 h/n use with 88% ofrespondents using CPAP every night. Study participationmay have been a confounding bias.N

Assessment of patient experiences using CPAP wasrestricted to side effects and measurement ofcompliance. Source of side effects and responseoptions were not reported.

Sage et al., 2001 [57]AustraliaQuality Fair

QuantitativeExploratoryRetrospective cross-sectionaldescriptive e survey

Setting not specified, purposive sample40 (30 men)Age 42e56 yRDI 23e71/hCPAP use one night, 3e8 h

Predicted one-month compliance with CPAP in recentlydiagnosed OSA patients using variables derived from theHealth Beliefs Model (HBM)d

Perceived barriers and benefits of CPAP were shown topredict compliance. Perceived benefits of CPAP wasinversely associated with % of days that CPAP not used.Participants’ confidence to use CPAP showed univariate, butnot multivariate, relationships with both variables.

Assessment of patient experiences using CPAP wasvia the ‘barriers to CPAP’ portion of thequestionnaire which related to expected futureCPAP experience based on experiences of the firstnight of use.Initial perceptions were shown to impact continuedCPAP use.

Sawyer et al., 2010 [58]USAQuality Good

Mixed methodsExploratoryProspective thematic analysis esemi-structured interviews

Urban veterans sleep clinic, purposivesample15 (13 men)Age 42e66 yAHI 27.5e79.5/hCPAP use 1e7 wk, 4.5e5.5 h/n

The influence on CPAP adherence of patients’ beliefs andperceptions of OSA diagnosis and CPAP treatment wasexamined preceding and during seven weeks posttreatment initiation. Quantitatively underpowered.Differing beliefs and perceptions between adherers (�6 h/n)and non-adherers (<6 h/n) included OSA risk perception,self-efficacy, outcome expectations, treatment goals,treatment facilitators and barriers.

Participants’ second interview alone exploredperceived effects of CPAP therapy. The experience ofpositive social influences motivated CPAP use,whilst those socially unsupported needed to be self-driven. Participants described using CPAP as a“botheration” and experienced difficultyreconciling pre-CPAP symptoms with treatment.

Smith et al., 1998 [59]USAQuality Good

QuantitativeExploratoryDescriptive correlational esemi-structured interviews &QOL tools

Setting not specified, purposive sample21 (13 men) & 20 caregiversAge 34e78 yOSA “severe”CPAP use 3e39 mo, 5e8.5 h/n

Barriers to CPAP use were explored, including learningneeds of patients and family and the knowledge and skillsneeded to manage CPAP post-discharge. There was a minorfocus on the patient/caregiver relationship.Learning needs related to troubleshooting equipment,maintaining mask comfort, managing headgear andmachine settings along with understanding OSA pathology.

Assessment of patient experiences using CPAP wasvia semi-structured family interview in the contextof experiencing difficulty with CPAP.Family members involved themselves withovercoming barriers to nightly CPAP use.

Tyrrell et al., 2006 [60]FranceQuality Fair

QualitativeExploratoryRetrospective e semi-structured interviews & survey

French Respiratory Homecare Network,purposive sample9 (8 men)Age 32e70 yAHI >30/hCPAP use >6 mo pre abandoning CPAP,4.5 h/n

The usefulness of HBM was explored to determinepsychological issues leading patients to abandon CPAP.Health beliefs influenced abandonment thoughrespondents were not preoccupied with OSA. CPAP wasstopped due to mask problems, machine noise, difficultiesor fatigue, and unmet expectations of a cure by CPAP. Oneparticipant understood the life threatening nature of OSAand two reported feeling better on CPAP.

Assessment of patient experiences using CPAP wasrestricted to perceptions of illness, treatmentproblems and reasons for abandoning CPAP.Participants experienced difficulty reconcilingsymptoms and diagnosis with goals andexpectations of treatment.

Veale et al., 2002 [61]FranceQuality Fair

QualitativeRetrospective discourseanalysis e semi-directiveinterviews around themes ofsleep, health & treatment

Pulmonary rehabilitation unit,purposive sample30 (gender not given) of which 15 werecommencing CPAPAge 39e74 yAHI 11e169/hCPAP use initial stages of treatment, notquantified.

How patients live with OSA was analysed in-depth.The CPAPmachinewas amajor preoccupation in initial levelof analysis and was perceived as a medical prosthesisidentifying participants as ill. Treatment was a focus for 15participants, but not for the investigator. The theme ofhealth was central to the discourse in the final level ofanalysis. Daytime sleepiness was overwhelminglyimportant to the participants. Users of CPAP for chronicobstructive pulmonary disease undetermined.N

Assessment of patient experiences focused onconcerns living with OSA rather than CPAP.Although two questions explored the difficultieswith and long term expectations of CPAP.CPAP was described as a problem or nuisance withnoise and nasal mask problems raised 21 times.CPAP users claimed better sleep on CPAP butexpressed general dissatisfaction. 17.7% ofrespondents hoped for a ‘miracle cure’.

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Table

3(con

tinu

ed)

Author/yea

r,co

untry/

quality

Studydesign

Settingan

dsample

aFo

cusan

dou

tcom

esof

each

studyb

Datarelatedto

personal

experiencesof

usingCPA

P

Wan

get

al.,20

12[62]

China

QualityPo

or

Quan

titative

Retrosp

ective

cross-sectional

e

phon

esu

rvey

Settingnot

specified

,purposivesample

193(162

men

)Age

42e62

yAHI40

e80

/hCP

APuse

27e96

mo,

h/n

unreported

Thepreva

lence

ofnon

-adheren

ceto

CPA

Pin

Tian

jinOSA

patients

was

assessed

.CPA

Pad

heren

cewas

show

nto

below

inTian

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hinaas

halftheco

hortab

andon

edor

faile

dto

commen

ceCPA

Ptrea

tmen

t.Initialperceptionsim

pactedco

ntinued

use.

Adheren

ceap

pea

redto

bedefi

ned

asco

ntinuingtrea

tmen

t.

Patien

tex

perience

ofad

heringto

CPA

Pwas

exam

ined

viathequ

estion

:how

man

yhou

rs/night

andhow

man

ynights/w

eekwas

CPA

Pused?Th

ose

dee

med

non

-adheren

twerethen

aske

dto

‘exp

lain

theirlack

ofad

heren

ce’.

Key

:AHI:ap

noe

ahyp

opnoe

aindex

;BMI:bo

dymassindex

;CP

AP:co

ntinuou

spositiveairw

aypressure;HBM:hea

lthbe

liefs

mod

el;OSA

:ob

structiveslee

pap

noe

a;QOL:

qualityof

life;

RCT

:random

ised

controlledtrial;RDI:

resp

iratorydisturban

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Quality assessment of studies is simpler within single method-ologies or where research design is similar; integrative reviewsinclude studies adopting a wide variety of methods creatingchallenges to quality assessment [66]. Qualitative studies weresystematically assessed via the critical appraisal skills pro-gramme (CASP) [65] quality assessment tool. It was noted thatCASP tools had not been developed for the quantitative researchdesigns in this review. Therefore, the Hawker et al. [64], qualityassessment tool was sourced for quantitative studies as it isflexible across all quantitative designs. Papers were assessed formethodological rigour and relevance to the research question.Assessment criteria included provision of a clear statement ofresearch aim; appropriateness of the methodology to theresearch question; appropriate recruitment strategy, datacollection and analysis; evidence of ethics and attention to bias.Studies evaluated via these criteria were assessed as good, fair,poor or very poor. Quality cross checking was carried out inde-pendently by KW and MG and consensus reached. The evaluationyielded two ‘poor’ studies [51,62], nine ‘fair’ studies[32,43,46,47,49,53,57,60,61], and eleven ‘good’ studies[42,44,45,48,50,52,54e56,58,59] (See Table 3).

Data synthesis

Data synthesis occurred in phases [67]. Data were extracted andtabulated to allow for identification of common themes by KWusing Microsoft Excel as a sorting tool. This enabled data aboutpatient experiences of using CPAP from studies of differing meth-odologies to be grouped into common themes [68]. The themeswere then refined [38,64] (See Table 4).

Results

Of the 22 papers included in the review seven used qualitativemethods [43,46,47,49,50,60,61], one mixed methods [58] and theremainder quantitative methods [32,42,44,45,48,51e57,59,62]. Fivestudies were exploratory and had small sample sizes[46,57,58,60,69]. Sample populations were recruited from urbanand/or rural sleep or pulmonary clinics. Three studies sampledfrom national networks [51,55,60]. Studies were conducted inAmerica [42,49,50,58,59], Canada [43,53], Sweden [44e48,54],Scotland [51], Germany [52], France [32,55,60,61], Italy [56], China[62] and Australia [57]. Participant age ranged between 30 and 75 ywith five studies including both younger and older participants[42,45,54,56,59]. Based on expected prevalence of OSA [4,25]women were under represented in all but five of the studies[42,48,50,52,59]. OSAwas reported as moderate to severe except inthree studies that did not report severity [49,50,55]. CPAP usevaried from just one night [42,57], to the first six months of use[47,50,56,58,61], to six months or more [44,52,54,55,60,62]. Sixstudies included participants who had abandoned treatment[32,43,50,52,59,60].

Table 4Phases of synthesis.

Phase Description

Immersionin the data

Re-reading included papers in detailand noting initial ideas

Initial coding Coding systematically across all included papersfor common topics and features of patientexperiences of using continuous positive airway pressure

Identifying themes Sorting codes into themesRefining themes Double checking that data fit with themes

and with the review question. Report writing to refinefinal themes

Adapted from Braun & Clarke, 2006 [67].


K. Ward et al. / Sleep Medicine Reviews xxx (2014) 1e10 7

The studies identified by this review of the literature regardingpersonal experiences of CPAP use all investigated factors that hel-ped or hindered CPAP use. Experiences were positively influencedby factors such as a good therapeutic response to CPAP, or nega-tively by factors such as side effects. Thematic analysis identifiedthree themes relating to experiences using CPAP: 1) users’ beliefsabout CPAP influence users’ experiences of CPAP; 2) experiencingCPAP is investigated and reported as synonymous with experi-encing difficulty; and 3) spouse and family influence users’ expe-riences of CPAP. The process of thematic analysis also highlightedthat users’ reporting of CPAP experiences was constrained byinvestigator defined assessment methods, as outlined in thefollowing section.

Overview of the state of the evidence

The study design of the included papers was identified as a keydeterminant of what the data captured about experiencing CPAP.Nine of the 22 studies investigated CPAP as part of a larger study[32,51e58,62], and none of the included studies captured all as-pects of experiencing CPAP. Commonly studies only investigateddiscreet aspects of experience and focused in particular upon dif-ficulties or problems using the CPAP device [43,49e51,56,60]. Anumber of studies examined only one discreet aspect of patients’experience, such as side effects [32,42,45,47,48,53,55,61].

Although the majority of studies investigated aspects of users’experiences of CPAP, these were based on predetermined responsecategories which had not been derived from user accounts of CPAPuse. For example, where side effects were listed as response options[32,42,44,45,48,51e53,55,57] these were derived from the CPAPliterature and expert or investigator opinion rather than from dataderived from CPAP users themselves. Responses were also limitedto a Likert [45,52,56,57] or categorical scale [42,53]. The exceptionto this was the SECI [45], which was developed on the basis of in-depth interviews with 23 CPAP patients, plus professional expertreview [46]. Though in-depth interviews allowed full expression ofCPAP users’ views in the development of SECI, subsequent admin-istration focused on only the perceived frequency, magnitude andimpact of side effects of CPAP [44,48].

The qualitative [43,46,47,49,50,60,61] and mixed methodsstudies [58] identified in the review captured aspects of experi-encing CPAP from the users’ perspectives through semi-structuredinterview and open ended questionnaire items. Attempts weremade to avoid leading the participant by using broader terms, i.e.,‘CPAP use’ rather than ‘adherence’, to promote freer expression ofparticipants’ perspectives [46]. However questions, and thereforefindings, were limited to factors influencing volition to use CPAP[43,46,49], difficulties with CPAP in the initial stages of treatment[47,50,61] or the expectations of long term treatment [58,60]. Twoquantitative studies [54,62], although soliciting the participantviewpoint via open ended questions, were less comprehensive intheir exploration. Wang et al. [62], asked just two simple questions:were the respondents’ adherent to their treatment and if not whynot? Holmdahl et al. [54], asked participants to describe only themost positive and most negative aspect of their treatment; thesewere reported respectively as reduced tiredness and dependenceon CPAP and mask problems.

Duration of CPAP use differed across the studies from just onenight [42,57] to many years [44e46,48,54]. Duration of use wasreported to influence the experiences participants had with theirCPAP. For example, the closer participants were to CPAP initiationthemore dissatisfied theywerewith CPAP [54,55,61]. However 90%[55] and 99% [54] of participants surveyed after six months or moreof CPAP use rated their satisfaction with the experience of CPAP asgood or excellent. The exception to this was participant samples

Please cite this article in press as: Ward K, et al., What is known about thsystematic integrative literature review, Sleep Medicine Reviews (2014),

where treatment had been abandoned due to dissatisfaction, irre-spective of CPAP duration [43,50,52,60].

Theme 1: users’ beliefs about CPAP influence users’ experiences ofCPAP

Users’ preconceived attitudes and expectations about CPAPprior to use influenced experiences, as did participant attitudestowards the therapy [44,46,57]. Perceptions that CPAP wouldimprove symptoms and reduce health risk [43,46,47] were rein-forced by reduced hypersomnia and improved function[43,46,49,54,57,58]. Conversely mild OSA symptoms or poorsymptom improvement increased the likelihood of poorer experi-ences with CPAP [44,53,57,58,60]. Unmet expectations such ascontinued hypersomnia, perceived as a failed ‘miracle cure’ [60,61],led to negative perceptions of treatment [43,47,49,61,62]. Patientsrated their ability to learn about CPAP, and the subsequent positiveeffect on CPAP use, as greater than healthcare personnel rated pa-tients’ ability [48]. Similarly a formal support group [49] andengaged caregivers in the family home [67] facilitated CPAP use bymitigating users’ experiences of potential barriers [43,58]. How-ever, initial and on-going practical difficulty using CPAP apparatus[46,49,54,57], including frustration and physical discomfort[47,57,60] negatively influenced the experience of using CPAP.

Fear of health and social consequences associated with CPAP usewas an identified sub-theme in six studies [43,46,47,57,58,61]. Notusing CPAP was perceived to risk relationships, productivity,participation in society, and driving licenses and manifested as fearthat motivated use [43,58]. Consequently not using CPAP triggeredguilt [43,46]. Participants felt ugly and embarrassed wearing theCPAP mask [43,45]. Others feared the stigma of being seen as odd[47,57] and were deterred by the perception that needing a medicalprosthesis identified them as ill [54,61].

However, hindrances, such as side effects and negative per-ceptions of others were not always of consequence, especially if theuser had high self-efficacy [55,58]. Positive mind-set [46,50] andconfidence using equipment [57] aided perseverance with therapy.Conversely those with negative mind-set experienced highermagnitude and frequency of side effects and were more likely toallow problems to hinder use [44].

Theme 2: CPAP users are primed to reflect negatively on experiencesof CPAP

Most studies were conducted from the standpoint that CPAP is adifficult therapy. The terms researchers used referred to problems,difficulties or trouble using CPAP [50,51,60,61], describing it as anuisance [51,53,56,60,61] and torment [58] that caused discomfort[32,47,49,53,55,60] and imposition [50] during sleep. CPAP useresulted in adverse side effects [32] to tolerate [55,61] or strugglewith [49]. In particular 17 of the included studies investigated orreported side effects of CPAP to some degree [32,42e48,50e53,55,56,59e61]. Nasal [32,42,45,49,51,53,55,58,60,61] and maskrelated problems [42,46,51,53] predominated, with 50% of partici-pants in one study [32] experiencing at least one side effect. Onestudy [57] in the review surveyed participants after just one nightof use in regard to future expectations of predetermined side ef-fects, whilst two others offered lists of side effects to participantsonly if they had problems [42,51].

Needing to persevere with therapy to master use of the device,particularly at the outset of treatment, was evident in the findings[43,47,49,50]. Participants expressed frustration [49,50] and‘botheration’ [58] using the device and needing to get used to or‘flunk’ their treatment [50,58]. Problem solving and adaptationover time were reported as essential to master the device [47,49]


Practice points

There is already evidence suggesting adherence rates to

CPAP treatment are low. This integrative review identifies

that when treating patients with CPAP for sleep apnoea it

may be useful to:

1) Be aware that existing attitudes of patients and their

partners towards CPAP treatment may influence experi-

ences with CPAP therapy.

2) Acknowledge to the patient that using CPAP can be

challenging, but that persevering can yield positive

results.

3) Engage the partner in the planned treatment regimen.

4) Use the SECI tool in practice to determine the extent to

which side effects impact the patient.


otherwise treatment was abandoned [50,58]. Three studies[52,58,60] investigated reasons for abandoning treatment, side ef-fects being a commonly cited cause [44,45,48]. Trade-off was madebetween the exhaustion of OSA and the discomfort of CPAP[32,43,49], whilst greater perceived discomfort and nuisance ofCPAP resulted in reduced use [56]. Only one study [51] focusedspecifically on the benefits of CPAP, although two other studies alsoreported better sleep [61], improved daytime function and reducedhypersomnia [51,53].

Theme 3: spouse and family influence users’ experiences of CPAP

Few papers addressed CPAP use in daily life, although six studiesexamined elements associated with those living and working withthe CPAP user [43,46,47,56,58,59]. Partners experienced personaland social distress prior to CPAP initiation, and were motivated tosupport the patient during the adaptation phase [47]. For example,married users’ problem solved and incorporated CPAP into theirlives quicker than unmarried users [58]. Committed partnersinvolved themselves with overcoming barriers hindering CPAP use[46,59], as did others in the family home [59]. Equally negative orabsent family support led to poorer experiences with treatment[43,46], with male spouses less involved with their partners’ CPAPtreatment than female spouses [59].

Discussion

Overall, analysis of the 22 papers in this review identifiedlimited information about experiences CPAP users have from theirown perspective. The literature reports phenomena that help orhinder CPAP use, with a focus on enhancing compliance. The choiceof research design, such as survey, pre-determined problemchecklists or interview questions, influenced what was reportedabout and limited capture of all aspects of experiences of usingCPAP. Understanding about users’ experiences using CPAP istherefore incomplete.

With the exception of SECI [45], checklist content was derivedfrom investigator knowledge and expert opinion rather thanopinions of individuals using CPAP. Dempsey and Dempsey [70]identify that some of the limitations of checklists includeassuming that all potential conditions of a phenomenon areidentified along with the risk of autosuggestion [70]. Reliabilityor validity [71] of checklists was also unclear in a number ofstudies as the source of side effects [32,51,55], or side effectslisted were unreported [52]. Both consistent and non-consistentCPAP users reported similar side effects with similar frequencywhen checklists were administered [42], suggesting that mech-anisms other than side effects alone impact volition to maintaintherapy. In contrast to checklists and survey questions, data fromsemi-structured interviews allowed open responses from theparticipant. However, by giving attention to influencing factors[43,46,60], such as being motivated to adhere [49] or identifyingreasons for abandoning CPAP [47,50], studies using semi-structured interviews were constrained by a predefined topicof adherence to CPAP. Dissatisfied users may have stoppedtreatment and been unavailable to the longer range studies thatdemonstrated satisfaction with therapy. Additionally, samplingparticipants in the initial stages of CPAP treatment may havefocused research on initial problems versus long termadaptation.

While CPAP use can be challenging, the problem oriented ter-minology adopted by most studies [32,47,49e51,53,55,56,58,60,61]may set up the expectation that all users will find CPAP problem-atic. However, few studies employed positive descriptors relating toCPAP use. Equally, anticipating side effects by documenting them in


the research instrument limits exploration to only problems usershave with CPAP [42,51,57]. Limiting the research instrument in thisway may exclude information from CPAP users who have no diffi-culty. Rather than considering CPAP as inherently problematic forall users the focus of future research might be how patients suc-cessfully manage their CPAP.

With the exception of the SECI development [45,46], moststudies focusing on difficulties using CPAP did not consult CPAPusers when developing surveys. Given the now accepted concept ofpatients as experts in their conditions and treatment, this is con-trary to current thinking [72e75]. Underestimating patients’ ca-pacity to maximise facilitators such as education and support fromhealth professionals, along with the capacity to adjust to CPAPmitigates collaborative partnership [72]. For example, one study inthe review showed CPAP users perceived that side effects had a lessadverse effect on adherence and that they were more able to learnabout OSA and CPAP than health professionals believed [48]. In thesameway, underutilising end users in the research setting increasespotential for missed avenues of exploration.

The importance of an engaged spouse and family was significantto the CPAP user, although limited research was found by this re-view [47,59]. This topic is underexplored and current studies arelimited by a focus on adherence. Equally the fear of social stigmawas underexplored within the studies of this review. Recognisingthat using CPAP is a social experience is important. Further inves-tigation into the significance of spouse and family engagement withthe CPAP user is warranted.

Conclusion

This is the first systematic review of patient experiences of CPAPand has identified limited evidence about CPAP experiences fromthe users’ perspective. Untreated OSA is associated with high per-sonal and economic cost and maintaining adherence to CPAP isacknowledged as a complex issue [76]. However, current research isconstrained by researchers’ concern with non-compliance whichlimits understanding and risks imposing unsuitable treatmentregimens on CPAP users. Typically experiences of CPAP are notdefined by the user, but from an ‘expert’ healthcare perspective,using language that defines CPAP as inherently problematic.Addressing CPAP users’ concerns through a problem orientedparadigm may miss important clues about how people experienceusing and successfully managing CPAP. Research that morecomprehensively involves CPAP users’ opinions using their ownwords is required to determine how patients manage this therapysuccessfully.


Research agenda

Research to date has focused on the problematic nature of

CPAP. However there is a dearth of research with those who

do not have problems with CPAP. Future research should

include:

1) Engaging end users in the development of assessment

and research tools, for example using cognitive inter-

viewing techniques.

2) Exploring the extent and significance of partner and

family engagement with CPAP on the users’ experience

of CPAP.

3) Interviews with patients who have used CPAP for an

extended period (for example longer than six months) to

identify which strategies support prolonged use.

K. Ward et al. / Sleep Medicine Reviews xxx (2014) 1e10 9

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Documents

What is known about the experiences of using CPAP for OSA from the users' perspective? A systematic integrative literature review