Impact of Functional Support on Health-RelatedQuality of Life in Patients with Colorectal Cancer

Shahnaz Sultan, M.D.1,2

Deborah A. Fisher, M.D., M.H.S.1,2

Corrine I. Voils, Ph.D.3

Anita Y. Kinney, Ph.D.4

Robert S. Sandler, M.D., M.P.H.5

Dawn Provenzale, M.D., M.H.S.1,2

1 Institute for Clinical and Epidemiological Re-search, Durham Veterans Affairs Medical Center,Durham, North Carolina.

2 Division of Gastroenterology, Department ofMedicine, Duke University Medical Center,Durham, North Carolina.

3 Center for Excellence in Primary Care, DurhamVeterans Affairs Medical Center, Durham, NorthCarolina.

4 Huntsman Cancer Institute, University of Utah,Salt Lake City, Utah.

5 Division of Gastroenterology and Hepatology,Department of Medicine, University of North Caro-lina–Chapel Hill, Chapel Hill, North Carolina.

6 Center for Gastrointestinal Biology and Disease,University of North Carolina–Chapel Hill, ChapelHill, North Carolina.

Supported in part by Grant 02926-02 from theVeterans Affairs Cooperative Studies Program(D.P.) and by Grants CA66635 and DK34987 fromthe National Institutes of Health (R.S.S.).

Address for reprints: Shahnaz Sultan, M.D., Box3913, Duke University Medical Center, Division ofGastroenterology, Durham, NC 27710; Fax: (919)416-5839; E-mail: sulta003@mc.duke.edu

Received August 18, 2004; revision received Sep-tember 3, 2004; accepted September 3, 2004.

BACKGROUND. It has been shown that social integration and the availability of

social support influence quality of life. However, little is known about the relation

between social support and mental and physical health in patients with colorectal

cancer. In the current study, the authors examined the effects of social network

size, as well as emotional and instrumental support, on health-related quality of

life (HRQOL) in patients with colorectal cancer.

METHODS. Six hundred thirty-six veterans with colorectal cancer were asked to

complete a telephone interview, which included a measure of social support (the

Berkman–Syme Index) and the Medical Outcomes Study Short Form 12-Item

Survey. Mean physical composite scale (PCS) and mental composite scale (MCS)

scores were compared across groups.

RESULTS. No difference in mean PCS or MCS scores was found between patients

who had larger social networks and patients who had smaller social networks. The

availability of emotional and instrumental support was associated with higher MCS

scores, whereas the availability of instrumental support was associated with lower

PCS scores.

CONCLUSIONS. Irrespective of network size, the availability of emotional support

and instrumental support had an impact on HRQOL in patients with colorectal

cancer. More emphasis needs to be placed on understanding how various types of

social support, individually and collectively, influence physical and mental health

in patients with colorectal cancer. Cancer 2004;101:2737– 43.

© 2004 American Cancer Society.

KEYWORDS: social support, quality of life, Medical Outcomes Study Short Form,colorectal cancer.

Colorectal cancer is a major cause of cancer-related morbidity andmortality, although significant advances have been made in the

treatment of patients with this disease. Traditionally, colorectal can-cer studies have focused on primary endpoints, such as responserates and survival. However, more recent literature has focused onhealth-related quality of life (HRQOL) as a primary outcome.1 In fact,the American Society of Clinical Oncology proposes that patient out-comes (e.g., HRQOL) may be just as important, if not more important,than disease outcomes (e.g., response and mortality).1

Quality of life in patients with cancer may be influenced by anumber of psychosocial factors, such as the availability and perceivedadequacy of social support. Social support itself is defined broadlyand encompasses many different and varying types of support, in-cluding structural and functional support.2 Structural support refersto the existence and establishment of social relations—specifically,marital status, number of friends and frequency of contact, andmembership in religious or other organizations.3 In contrast, func-

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© 2004 American Cancer SocietyDOI 10.1002/cncr.20699Published online 9 November 2004 in Wiley InterScience (www.interscience.wiley.com).

tional support includes emotional and instrumentalsupport and refers to the resources that individualswithin a patient’s social network provide. For exam-ple, emotional support encompasses having individu-als who are available to listen, sympathize, providereassurance, and make the patient feel valued andcared for, whereas instrumental support includes as-sistance with activities of daily living or with house-hold chores, errands, and transportation to appoint-ments.4 In general, more emotional and instrumentalsupport (functional support) is available to a patientwhen there is a larger social network (structural sup-port).

The availability of social support and a greaterdegree of social integration are associated with betterquality of life in patients with breast cancer and pa-tients with prostate cancer. However, there is limitedinformation on the association between social supportand quality of life in patients with colorectal can-cer.5–12 Moreover, even less information is availableon how different types of social support—i.e., struc-tural support versus functional support (emotional orinstrumental)—influence quality of life.10,13,14 Emo-tional or instrumental support may in fact be moreimportant than structural support for patients withcancer because these patients may have more diffi-culty coping with their disease and may require addi-tional help with daily activities due to the accompa-nying physical limitations.

The objective of the current study was to examinethe relation between social support and HRQOL, asmeasured by the Medical Outcomes Short-Form 12-Item Survey (SF-12), in veterans diagnosed with coloncancer.15 We used the Berkman–Syme Social NetworkIndex (SNI), a widely used and well studied measure ofstructural support, to determine social network size.16

We previously used these instruments in a nonveteranpopulation to study the role of social support andreligious involvement for black patients and white pa-tients with colorectal cancer.17 Because we were par-ticularly interested in studying various types of socialsupport, we also asked questions about the availabilityof functional support—in particular, emotional andinstrumental support—and whether the amount ofsuch support was adequate.

MATERIALS AND METHODSData CollectionThe data for this report were collected as part of alarger prospective study that examined the risk factorsfor advanced colorectal cancer at 15 Veterans Affairscenters throughout the country. Six hundred thirty-sixstudy participants ages 40 – 85 years who had a pri-mary diagnosis of histologically proven adenocarci-

noma of the colon or rectum between July 1, 1997, andJanuary 1, 2001, were recruited from tumor registriesusing the Decentralized Hospital Computer Program(Department of Veterans Affairs, Washington, DC). In-formed consent was obtained from each participant,either by telephone or by mail, in accordance with therequirements of each site’s institutional review board.Structured telephone interviews were then conductedby trained interviewers. Information relating to dis-ease stage was obtained from pathology reports andmedical records.

HRQOL AssessmentHRQOL was measured using the SF-12, which is avalidated 12-item subset of the Medical OutcomesShort-Form 36-Item Survey.18 The SF-12 measureseight domains of health and is useful in evaluatingphysical and mental limitations imposed by healthproblems and in assessing the individual patient’s vi-tality and general health perceptions. After summingacross items, the raw scale scores were transformedinto 2 summary scores, which ranged from 0 (worstpossible function) to 100 (best possible function): theMCS scale, which reflects mental health status, andthe PCS scale, which reflects physical health status.Approval to analyze the data was obtained from theMedical Outcomes Trust (Waltham, MA).

Social Network AssessmentQuestions pertaining to structural aspects of socialsupport were derived from the Berkman–Syme SNI,16

an index that was developed to measure the degree ofsocial integration by assessing various types of socialties. Patients were asked whether they had a spouse orpartner and whether they had a confidant they couldtalk to about their personal problems or health. Inaddition, patients were asked to provide the numberof relatives and friends with whom they felt close andthe number of relatives and friends seen at least oncea month. Finally, patients were asked whether theybelonged to a social or recreational group, a laborunion, professional organization, church group, orgroup concerned with children, community better-ment, charity, or service. A weighted index of intimatecontacts was combined with membership in churchesand groups to yield a 12-level index that was thendivided into 4 categories, ranging from I (few socialties) to IV (most social contacts).

The emotional and instrumental support ques-tions were derived from the Yale and Harvard AgingProject questionnaire.19 The presence of emotionalsupport was measured using the following question:Could you count on anyone to provide you with emo-tional support (talking over problems or helping you

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make a difficult decision)? Possible responses includedyes, no, or did not need help. Instrumental support wasmeasured by the item: When you need some extra help,can you count on anyone to help you with daily taskslike grocery shopping, house cleaning, cooking, tele-phoning, or giving you a ride? Response options in-cluded yes, no, or did not need help.

Finally, patients who responded yes to the ques-tion about available emotional and instrumental sup-port were asked to complete questions regarding ad-equacy. The adequacy of emotional and instrumentalsupport was assessed by the following items: Couldyou have used more emotional support than you re-ceived? and Could you have used more help with dailytasks than you received? Possible responses included alot, some, a little, none at all, or received sufficient help.

Statistical AnalysisStatistical analyses were performed using SPSS soft-ware (Version 11.5; SPSS Inc., Chicago, IL). Outcomevariables and MCS and PCS summary scores wereanalyzed as continuous variables. Age was categorizedinto 4 groups as follows: � 54 years, 55– 64 years,65–74 years, and � 75 years. Educational level com-pleted was categorized as elementary/middle school,high school, college, or graduate school. The adequacyof emotional and instrumental support was dichoto-mized as needs more or sufficient.

Analyses of variance were performed to examinethe relationship between mean PCS and MCS scoresand all independent variables, including age, race,education, disease stage, SNI, and emotional and in-strumental support measures. Only patients who in-dicated that emotional support was available wereincluded in the analyses of adequacy of emotional andinstrumental support. For those analyses, indepen-dent t tests were performed to compare patients whoindicated sufficient emotional or instrumental sup-port with patients who indicated insufficient emo-tional or instrumental support. A P value � 0.05 wasconsidered significant for all statistical tests.

RESULTSDescriptive characteristics are summarized in the firstcolumn of Table 1. The mean age (� standard devia-tion [SD]) of patients in the study was 66.5 � 8.7 years(range, 40 – 80 years). The majority of patients weremale (98%) and white (80%). Approximately 262 pa-tients (41%) reported that they had received a collegeeducation, and 371 patients (58.3%) were married orwere living with a partner. Information regarding theextent of disease was available for 515 patients, 161 ofwhom had Stage I disease confined to the colon wall,292 of whom had locally advanced (i.e., Stage II) dis-

ease (20.4%) or Stage III disease (25.5%), and 62 ofwhom had metastatic (Stage IV) disease (9.7%).

In the current population of 636 patients withnewly diagnosed colorectal cancer, the mean � SDPCS score was 37.3 � 11.4, and the mean � SD MCSscore was 51.6 � 11.0. In bivariate analyses, there wereno statistically significant differences in mean PCSscore between the groups based on age, race, educa-tion level, or stage of disease. However, there was anassociation between marital status and PCS: Patientswho were married or who were living as married hada poorer physical health status compared with pa-tients who were not. Mean MCS scores did not differbetween groups based on race, education level, mar-ital status, or stage of disease, but there was a statis-tically significant association between age and MCSscore. Follow-up t tests showed that the patients age� 54 years had a significantly poorer quality of lifecompared with patients in the other 4 age groups (P� 0.01).

To examine structural support, patients were clas-sified into four levels of social integration based on theSNI (Table 2). One hundred eighty-one patients(28.5%) were characterized as most integrated, with8 –12 social contacts or ties, and 97 patients (15.3%)were classified as being isolated to a great extent, withonly 1 social connection.

There was no association between structural sup-port and either HRQOL index, as mean MCS and PCSscores did not differ across the four levels of socialintegration (Table 2). Only a 0.2-point difference inPCS score and a 2.0-point difference in MCS scorewere seen between patients who were categorized asmost integrated and those who were categorized asmost isolated according to the SNI.

Emotional support was available to the majority ofpatients (62.9%) (Table 3). Among the patients whohad available support, 328 (82.8%) reported receivingsufficient support, whereas 68 (17.2%) reported thatthey needed additional support. Instrumental supportwas available to 406 patients (63.8%). Of those, 79.6%reported that the amount of instrumental supportthey received was adequate, whereas 20.2% reportedthat more support would have been useful.

The availability of emotional support was signifi-cantly associated with better mental health. Follow-upt tests indicated that patients who did not have emo-tional support had significantly worse mental healthscores compared with patients who did have supportavailable (P � 0.01) and patients who did not needhelp (P � 0.01). The association between PCS scoreand availability of emotional support was not signifi-cant.

The availability of instrumental support also was

Functional Support and Colorectal Cancer/Sultan et al. 2739

significantly associated with better mental healthscores. Similar to the pattern of findings with respectto emotional support, patients who did not have in-strumental support available had significantly worsemental health scores compared with patients who didhave support available (P � 0.01) and patients who didnot need help (P � 0.01). There was also a significantassociation between the PCS score and the availability

of instrumental support. However, the pattern of find-ings was contrary to what was observed in the analysisof MCS scores. Specifically, patients who had instru-mental support available had worse PCS scores com-pared with patients who did not have support avail-able (P � 0.01) and patients who did not need help (P� 0.01).

Finally, when the adequacy of support was ana-

TABLE 1Patient Characteristics

Characteristica No. of patients (%)

PCS score MCS score

Mean � SD P value Mean � SD P value

Age (yrs)� 54 82 (12.9) 34.9 � 10.7 0.07 46.8 � 13.2 0.01b

55–64 146 (22.9) 36.2 � 11.8 52.2 � 11.065–74 284 (44.5) 38.2 � 11.6 52.6 � 10.2�75 124 (19.4) 37.9 � 10.6 51.8 � 10.3

GenderMale 623 (98) 37.3 � 11.4 0.66 51.6 � 11.0 0.65Female 13 (2) 35.9 � 11.0 50.2 � 11.4

RaceWhite 508 (80) 37.3 � 11.5 0.91 51.9 � 10.8 0.19Nonwhite 128 (20) 37.2 � 11.1 50.5 � 11.4

Educational levelElementary/middle 81 (12.7) 36.5 � 12.0 0.08 51.9 � 10.5 0.91High school 293 (46.1) 38.0 � 11.5 51.8 � 10.5College 230 (36.2) 36.1 � 10.9 51.2 � 11.5Graduate school 32 (5.0) 40.7 � 11.5 51.9 � 13.0

Married/living as marriedYes 371 (58.3) 36.3 � 11.1 0.01b 51.8 � 11.1 0.58No 265 (41.7) 38.6 � 11.1 51.3 � 10.8

Disease stageI 161 (25.3) 38.4 � 11.0 0.07 52.0 � 10.8 0.83II 130 (20.4) 37.6 � 11.9 52.1 � 11.3III 162 (25.5) 38.0 � 10.4 51.0 � 11.1IV 62 (9.7) 34.2 � 12.2 52.3 � 10.4Missing 121 (19.0) 35.9 � 12.0 51.0 � 11.0

PCS: physical composite scale; MCS: mental composite scale; SD: standard deviation.a For each characteristic, differences between/among mean values were tested using analysis of variance.b Significant at P � 0.05.

TABLE 2Structural Support (Social Network Index) and Health-Related Quality of Lifea

Social integration (level) No. of patients (%)

PCS score MCS score

Mean � SD P valueb Mean � SD P value

Most integrated (IV) 181 (28.5) 37.3 � 11.4 0.25 52.1 � 11.0 0.22Moderately integrated (III) 129 (20.3) 36.0 � 11.0 52.9 � 10.3Moderately isolated (II) 229 (36.0) 38.2 � 11.3 51.1 � 11.4Most isolated (I) 97 (15.3) 37.5 � 11.4 50.1 � 10.6

PCS: physical composite scale; MCS: mental composite scale; SD: standard deviation.a Differences among mean PCS and mean MCS scores were tested using analysis of variance.b Significance was set at P � 0.05.

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lyzed, we found that patients who reported adequateemotional and instrumental support had higher men-tal health scores, and the difference in MCS scores wasstatistically significant. We did not find a significantassociation between adequacy of support and physicalhealth scores.

DISCUSSIONIn the current study, we examined the associationbetween various types of social support and quality oflife in veterans with colon cancer. One particularlysignificant finding was that social network size was notassociated with clinically meaningful differences inMCS and PCS scores; instead, mean MCS and PCSscores were relatively similar across various levels ofsocial integration. Most studies that have investigatedthe relation between social support and health statushave focused on the importance of having large socialnetworks that consist of many contacts.7,11,16,20 –27 Theinvestigators involved in those studies posited that thesize and degree of integration within a social networkcould influence the availability of different types ofsupport and resources from members of the net-work.2,10,21,28 A few studies have tested this hypothesisin patients with cancer and have shown that a greaterdegree of social integration is associated with bettermental health.7,10 –12 In breast cancer survivors, socialintegration was associated with better quality of life.7

In addition, in the lone study to evaluate the correla-

tion between social support and quality of life in pa-tients with colon cancer, Sapp et al.12 demonstratedthat social network size was associated with HRQOL,and mental health in particular, in long-term femalesurvivors of colorectal cancer. Our findings were notconsistent with those studies, however, because wedid not find an association between physical andmental health scores and various degrees of socialintegration. It has been suggested that social networksare necessary but not sufficient, in and of themselves,for drawing support from others.28 Additional modify-ing behaviors or factors, such as coping style andpersonality, may influence an individual’s ability toactually draw upon or make use of specific types ofsupport from the social environment.28

We also found that individuals with colorectalcancer who did not have available emotional supporthad mean MCS scores that were approximately 6 –7points lower compared with the MCS scores of indi-viduals who had available support. The difference inmental health scores between these two groups wasstatistically significant and can be considered clini-cally relevant.18 This finding is consistent with otherpublished works, which have demonstrated a linearrelationship between emotional support and qualityof life in patients with cancer.2,8,10 Emotional supportis the most helpful type of support and the type mostneeded by patients.2 Studies have shown that patientswho report greater levels of emotional support have

TABLE 3Functional Support Measures and Health-Related Quality of Lifea

Support measure No. of patients (%)

PCS score MCS score

Mean � SD P value Mean � SD P value

Availability of emotional supportb

Yes 396 (62.9) 37.3 � 11.1 0.34 52.1 � 10.7 0.01c

No 89 (14.1) 35.5 � 11.3 46.7 � 12.3Does not need help 145 (23.0) 38.3 � 11.9 53.3 � 10.0

Adequacy of emotional support (n � 396)Sufficient 328 (82.8) 37.7 � 11.1 0.08 53.1 � 9.90 0.01c

Needs more 68 (17.2) 35.1 � 10.9 47.1 � 12.9Availability of instrumental supportd

Yes 406 (63.8) 35.9 � 11.2 0.01c 51.8 � 11.0 0.01c

Noc 48 (7.5) 40.1 � 11.6 46.5 � 12.1Does not need help 180 (28.3) 39.7 � 11.2 52.6 � 10.3

Adequacy of instrumental support (n � 406)Sufficient 323 (79.6) 36.4 � 11.4 0.15 53.1 � 10.3 0.01c

Needs more 82 (20.2) 34.4 � 10.4 46.4 � 12.0

PCS: physical composite scale; MCS: mental composite scale; SD: standard deviation.a Among groups, differences between among mean MCS and PCS scores were tested using analysis of variance.b Six responses were missing.c Significant at P � 0.05.d Three responses were missing.

Functional Support and Colorectal Cancer/Sultan et al. 2741

superior coping skills and better social and emotionaladjustment capabilities.2,29

Another important finding in the current studywas that the availability of instrumental support hadopposing effects on physical and mental health statusin patients with colon cancer. Like emotional support,patients who had instrumental support had betterMCS scores compared with patients who were withoutinstrumental support. However, having available in-strumental support was associated with lower physicalhealth scores. Patients who reported having availableinstrumental support had mean PCS scores that were4 –5 points lower than the scores of patients who re-ported not having any instrumental support. This as-sociation between instrumental support and PCSscore may be attributable to the actual use of instru-mental support. It is individuals who have poor phys-ical health and lower levels of physical functioning,specifically, who are relying on their social networks toreceive instrumental support, such as help with tasksand financial assistance. To the best of our knowledge,only two studies to date have examined the relationbetween instrumental support and quality of life inpatients with cancer.10,13 In a single study of 49women who underwent mastectomy, the authorsfound that instrumental support positively influencedmental health in patients with limited physical disabil-ity. In a more recent study of patients with breastcancer, Bloom et al.10 reported findings that were sim-ilar to ours and speculated that individuals withgreater physical limitations or needs were more likelyto rely on others for assistance and to use more in-strumental resources.

Finally, the current study demonstrated that anindividual patient’s subjective perception of havingadequate support also was associated with mentalhealth. Patients who felt that they had inadequateemotional and instrumental support had lower mentalhealth scores compared with patients who reportedadequate support. However, no difference was seen inPCS scores. This is consistent with other studies thathave emphasized that perceived social support is amuch better predictor of quality of life because it takesinto account the patient’s subjective feeling that he orshe is receiving the support that is needed to functionand to cope with their disease.2,30 –32 In fact, it is be-lieved that perceived social support is more importantthan social network size or quantity of support. Thesefindings underscore the need to specifically examineadequacy and availability as separate and unique en-tities in the context of studying various types of socialsupport.

One limitation of the current study was that in-formation regarding social support was obtained in

the postcancer diagnosis setting, which may have in-fluenced patient responses to questions regarding so-cial support. We tried to overcome this problem byphrasing the questions about social support in theprecancer context. All questions regarding social sup-port started with the following phrase: Before yourillness… In addition, all questionnaires were adminis-tered at least 6 months after surgical resection to allowfor recovery from the surgery.

An additional limitation of the current study wasthat longitudinal data were not available; thus, wecould not make any inferences about causality or as-sess the stability of social networks over time. Finally,our study primarily involved men (98%) who were partof the Veterans Affairs Health System; thus, our find-ings may not be generalizable to women or to nonvet-eran patient populations.

In conclusion, few studies in the literature havedistinguished among different types of social supportand their impact on quality of life in patients withcancer. Furthermore, very few studies have evaluatedthe influence of social support on health outcomesexclusively in patients with colon cancer, underscor-ing the need for further research in this area. Under-standing how social support influences physical andmental health is important because social environ-ments or social networks potentially are modifiable.By further developing or strengthening existing socialstructures, it may be possible to improve an individ-ual’s quality of life. More emphasis must be placed onunderstanding how various types of social support,individually and collectively, influence physical andmental health as we expand our knowledge of howsocial support affects health outcomes.

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