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This publication is funded by MedImmune, LLC.

Volume 18, No. 1Supplement 2January 2009

Supplement to

Impact of RSV:Implications for Managed Care

By Doris Makari, MD, and J. Michael Hoopes, PharmDMedical and Scientific Affairs, MedImmune, LLC.

With a managed care commentary by Norman White, MDMedical Director, Presbyterian Health Plan, Albuquerque

CB_RSV2_v83.2.Final.kta.qxp:Clinical Brief 1/9/09 4:39 PM Page MC1

increased by 39 percent between 1997 and 2002 and totalledmore than $1.1 billion in 2002 (McLaurin 2005). Further-more, RSV hospitalization of infants is associated with sub-stantial time, out-of-pocket, and productivity losses for theaffected families and, by extension, society in general (Leader2003b).

These data underscore the need for the early and carefulidentification, evaluation, and management of infantsyounger than 1 year of age — particularly premature infants— who may be at high risk of severe RSV disease.

Why are premature infants at high risk?Acute infection of the lower respiratory tract, which mani -

fests clinically as bronchiolitis or pneumonia, is the hall-mark of severe RSV disease. RSV outbreaks generally occurduring the annual RSV season of November through April,although the season can vary greatly throughout the coun-try or during any 1 year, and even among close communi-ties (AAP 2006, Mullins 2003, Panozzo 2007).

Infection is easily transmitted, usually hand to hand or bycontact with contaminated surfaces, such as kitchen andbathroom countertops, and even toys, clothing, and otherobjects (AAP 2006, Hall 1980). Spread in households andchild-care centers is common, as is reinfection (AAP 2006,Hall 2001).

Preterm infants (35 weeks or less ges-tational age [GA]); infants with congen-ital heart disease (CHD); and prematureinfants with chronic lung disease (CLD)are known populations at an increasedrisk of developing severe RSV disease(AAP 2006, Boyce 2000, Law 2004).

Premature infants have an elevated riskof RSV susceptibility primarily becausethey have fewer disease-fighting anti -bodies — maternal antibody transfergenerally occurs during the thirdtrimester or after 28 weeks (Yeung 1968).Also, their lungs are less mature than thelungs in full-term infants (Langston1984). As shown in Figure 1, preterminfants have about half the lung volumeof full-term infants, with a thicker air-space wall, which results in impaired gasexchange; alveoli, the distal, tiny grape-

Respiratory syncytial virus (RSV) is a major cause of lowerrespiratory tract infections — particularly bronchiolitis —in infants and young children in the United States, and is theleading cause of hospitalization of infants younger than 1year of age (Leader 2002, Shay 1999).

Up to 126,000 infants are hospitalized each year becauseof severe RSV disease, 20 percent of whom are prematureinfants, and the number and rate of hospitalizations may beincreasing (Leader 2002, Shay 1999). In addition, it is esti-mated that up to 400 children younger than 1 year of age dieeach year due to severe RSV infection (Shay 2001, Thomp-son 2003). RSV disease contracted in infancy may also beassociated with respiratory ailments later in life, such asrecurrent wheezing and physician-diagnosed asthma inchildhood (Sigurs 2005, Stein 1999).

The economic burden on the U.S. health care system is significant. Direct medical costs of RSV- associated hospitalcare for infants (emergency department visits and inpatientstays) over a 4-year period, 1997 to 2000, amounted to anestimated $3 billion, or an annual average cost of $750 mil-lion (Leader 2003a). Between 1997 and 2002, the RSV hos-pitalization rate among infants younger than 1 year of ageincreased by 25 percent, with the highest hospitalization ratebeing among infants during the first 3 months of life (45.3per 1,000) (McLaurin 2005). Mean hospital charges for RSV

Impact of RSV: Implications for Managed CareRespiratory syncytial virus (RSV) disease is the leading cause of infant hospitalization, andpremature infants are particularly at high risk. Timely RSV management strategies can helpreduce costly RSV hospitalizations.

FIGURE 1Lung development in infants up to full term

GA= gestational age.Adapted from Moore 2003

8 weeks GA 16 weeks GA

Fetal development Preterm Term

24 to 35 weeks GA

infants 32 to 35weeks GA arewithin thesame stage oflung develop-ment as infants28 to 32 weeksGA

36 weeks GA to 3 years

2

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like structures that are the principal site ofgas exchange in the lungs are not uni-formly present until 36 weeks GA(Langston 1984).

Preterm birth rates vary among racial,ethnic, and socioeconomic groups (Mar-tin 2007). Of infants born preterm,approximately 75 percent are born 32 to35 weeks GA (Figure 2), and about twothirds of these infants are likely to havetwo or more documented RSV risk fac-tors (Figure 3).

Although prematurity alone can sig-nificantly increase the risk for severe RSVdisease, the presence of one or more otherrisk factors listed in the Table on page 4may also increase susceptibility. Strongrecent evidence cited in the literature(Table) supports that exposure to tobaccosmoke, young chronological age, andcrowded living conditions are linked toan increased risk of RSV disease.

RSV is costly Actuarial cost analyses show that

health care costs for infants 33 to 36weeks GA who have a history of RSV hos-pitalization are substantially higher than

FIGURE 3Infants born 32 to 35 weeks GA are likely to have two or more documented RSV risk factors

FIGURE 232 to 35 weeks GA infants — a birth cohort at high risk for RSV

Total births(4,138,349)

28–31weeks GA

(15.8%)

Percent distribution of U.S. pretermbirths, 20051,2

Percentage of U.S. infantsborn preterm, 20051,2

<28 weeks GA (9.6%)

32–35weeks GA

(74.5%)

• Of the 7.9% of U.S. infants born preterm (≤35 weeks GA) in 2005, approximately 75% were born 32 to 35 weeks GA.1,2

• Preterm birth rates vary among racial-ethnic and socioeconomic groups. Ratesare highest for African-Americans and have increased by one third amongwhites and by 9% among Hispanics since 1990.1

GA=gestational age.1 Martin JA, Hamilton BE, Sutton PD, et al. Division of Vital Statistics. Births: final data for 2005.

Natl Vital Stat Rep. 2007;56:1–104.2 Data on file, MedImmune, LLC.

* Survey included a review of 905 patient charts from pediatricians who manage patients ≤35 weeks GA.1† Risk factors include school-aged siblings, daycare attendance, exposure to environmental air pollutants or tobacco smoke, severe neuromuscular disease,

congenital abnormalities of the airways, low birthweight (<2500 g), crowded living conditions (≥4 in household), multiple births, and family history of asthma.1

1 Data on file, MedImmune, LLC.2 Martin JA, Hamilton BE, Sutton PD, et al. Division of Vital Statistics. Births: final data for 2005. Natl Vital Stat Rep. 2007;56:1–104.

Preterm births (≤35 weeks GA)

7.9%

Two thirds of these infants have two or more documented risk factors1

~75% of those preterm infants are 32 to 35 weeks GA1

7.9% of all infantsare born preterm(≤35 weeks GA)1,2

All infants

In a recent chart survey,* approximately two thirds of 32- to 35-week GA infants had two or more documented RSV risk factors.†

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health care costs for infants 33 to 36 weeks GA with no his-tory of RSV hospitalization, or even with full-term infantswho have a history of RSV hospitalization (Figure 4). Inaddition, as shown in Figure 5, the RSV hospitalization ratefor preterm infants is nearly double the rate for low-risk, full-term infants. Also, infants born 33 to 35 weeks GA havedouble the hospital length of stay, double the length of stay

in the neonatal intensive care unit (NICU), and more thantriple the intubation rate of full-term infants (Figure 6).

Managing RSVPrematurity is associated with a greater use of hospital

resources and poorer clinical outcomes during RSV hospi-talization (Boyce 2000, Horn 2003, Law 2002). A comprehen-

FIGURE 4Infants with a history of RSV hospitalization are associated with increased health care costs

* The results shown are based on a study of 50,184 commercially insured infants born in calendar year 2004 who survived their first year of life. The resultsreflect the mix of risk characteristics underlying the study population. Care should be used when generalizing the results to other infant populations. Thecosts associated with the first year of life are influenced by factors which could result in material differences in observed results, including the delivery sys-tem and overall cohort morbidity (i.e., presence of other significant medical conditions).

GA=gestational age.Source: Milliman Report, Feb. 19, 2007

In the first year of life, infants 33 to 36 weeks GA with a history of RSV hospitalization cost:– Nearly 5 times as much as infants 33 to 36 weeks GA with no history of RSV hospitalization– Nearly 4 times as much as full-term infants with a history of RSV hospitalization

Average total cost per infant during the first year of life (excluding the birth hospitalization)*

$26,187

$7,827$2,143

$82,822

$37,168

$10,298

No history of RSV hospitalization

History of RSV hospitalization

<33 weeks 33–36 weeks Full term

Ave

rag

e p

aym

ent (

$)

100

80

60

40

20

0

TABLE Risk factors associated with an increased risk of RSV hospitalization

Risk factor Odds ratio

Multiple births14,15 2.414, 7.015,Low birthweight (<2500 g)14,16,17,18, 22 2.416, 6.517, 2.218, 13.914, 7.70 (<1.5 kg) or 2.43 (1.5–2.49 kg)22

Crowded living conditions3,11,5,19 2.411, 1.93, 4.75, 1.9319

Family history of asthma3,11,20,21 2.111, 1.93,2.220, 1.7421

Young chronological age (<12 wks)1,2,3,22 1.631, 4.92, 3.953, 8.46 (<3 mos) or 4.15 (3–5 mos)22

Exposure to environmental smoke1,2,11,12,13,21,23 1.631, 3.211, 1.872, 1.2821, 5.0623

*School-age siblings1,2,3 1.61, 2.762, 2.83

*Day care attendance2,4,5,6 1.64, 2.25, 2.06, 12.22

*Exposure to environmental air pollutants7 No quantitative analysis published(excluding tobacco smoking studies)

*Severe neuromuscular disease8,9 4.94 PICU admissions10

*Congenital abnormalities of the airways8 No quantitative analysis published

* AAP identified risk factors.

PICU=pediatric intensive care unit.

Sources: 1Carbonell-Estrany 2001, 2Law 2004, 3Figueras-Aloy 2004, 4Celedon 1999, 5Holberg 1993, 6Marbury 1997, 7AAP 2006, 8Arnold 1999, 9Panitch 2004,10Wilkesmann 2007, 11McConnochie 1986, 12DHHS 2006, 13Hall 1984, 14Holman 2003, 15Simoes 1993, 16Lanari 2002, 17Leader 2003a, 18Cilla 2006, 19Anderson 1988,20Wang 1998, 21Carroll 2007, 22Rossi 2007, 23Von Linstow 2008

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FIGURE 6Effects of prematurity on RSV-related hospital resource use and outcomes*

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sive and proactive RSV management program for infantsyounger than 1 year at high risk of RSV infection, with anemphasis on preterm infants, can help reduce NICU admis-sions and RSV hospitalizations and their associated costs.

Optimally, such a program should ensure the care of aninfant prior to hospital discharge and throughout the infant’sfirst RSV season, which can be determined by accessing localRSV epidemiology data. Case management should beencouraged. Hospital case managers can quickly identify andevaluate high-risk infants. Managed care case managers canfacilitate the prompt and smooth transition of these infantsfrom the hospital or NICU setting to the clinical setting orhome so that RSV management can continue. Parent educa-tion is also important, and parents and other caregiversshould be counseled on the importance of hand washingand other sanitation safeguards in the home.

SummarySevere RSV disease, manifested as bronchiolitis or pneu-

monia, is the leading cause of hospitalization of infantsyounger than 1 year of age in the United States. Infants born35 weeks or less GA are particularly at high risk of severe RSVdisease, which may result in frequent NICU admissions orlong hospital stays and additional health care utilizationover the first 12 months of life. This care is costly — infants33 to 36 weeks GA with a history of RSV hospitalization incurcosts that are nearly 5 times as much as costs for 33 to 36weeks GA infants with no history of RSV hospitalization.

FIGURE 5RSV hospitalizations in Tennessee Medicaidinfants*

60

50

40

30

20

10

0BPD CHD ≤28 wks

GA29 to <33

wks GA33 to <36

wks GALow-risk**

*Data derived from a retrospective analysis of 3,553 hospitalizations forRSV-related illness in children <3 years of age enrolled in the TennesseeMedicaid system between July 1989 and June 1993.

**Low-risk defined as children born at term with no underlying medicalconditions.

BPD=bronchopulmonary dysplasia, CHD=congenital heart disease, GA=gestational age.

Source: Adapted from Boyce 2000

4.4

9.412.1

56.3

8.08.2

RSV

-rel

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mo

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ICU=intensive care unit, LOS=length of stay.* Based on a retrospective multicenter study that measured the severity of illness in 304 infants aged ≤1 year who were admitted to the hospital with confirmedRSV from April 1995 to September 1996.

a Statistically significant difference from full-term infants (Duncan multiple range test).b P values derived from a comparison of 4 GA groups (≤32 weeks GA, 33–35 weeks GA, 36 weeks GA,≥37 weeks GA).Adapted from Horn 2003

40

30

20

10

4.1 days

8.4 daysa

3.8 days

7.7 daysa

12.1%

38.7%a

Per

cen

tag

e

Full term(n=215)

33–35 wksGA (n=31)

Full term(n=215)

33–35 wksGA (n=31)

Full term(n=215)

33–35 wksGA (n=31)

(P<.0001)b (P=.021)b (P=.002)b

Doublehospital LOS

DoubleICU LOS

Tripleintubation rate

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Celedon JC, Litonjua AA, Weiss ST, Gold DR. Daycare attendance inthe first year of life and illnesses of the upper and lower respira-tory tract in children with a familial history of atopy. Pediatrics.1999;104:495–500.

Cilla G, Sarasua A, Montes M, et al. Risk factors for hospitalizationdue to respiratory syncytial virus infection among infants in theBasque country, Spain. Epidemiol Infect. 2006;134:506–513.

DHHS (U. S. Department of Health and Human Services). Thehealth consequences of involuntary exposure to tobacco smoke:a report of the Surgeon General (full report).«www.surgeongeneral. gov/ library/secondhandsmoke». AccessedSept. 5, 2008.

Figueras-Aloy J, Carbonell-Estrany X, Quero J, for the IRIS StudyGroup. Case-control study of the risk factors linked to respira-tory syncytial virus infection requiring hospitalization in pre-mature infants born at a gestational age of 33–35 weeks inSpain. Pediatr Infect Dis J. 2004;23:815–820.

Hall CB, Douglas, RG Jr., Geiman, JM. Possible transmission byfomites of respiratory syncytial virus. J Infect Dis. 1980;141:98–102.

Hall CB, Hall WJ, Gala CL, et al. Long-term prospective study in chil-dren after respiratory syncytial virus infection. J Pediatr. 1984;105:358–364.

Holberg CJ, Wright AL, Martinez FD, et al. Child day care, smokingby caregivers, and lower respiratory tract illness in the first 3years of life. Pediatrics. 1993;91:885–892.

Holman RC, Shay DK, Curns AT, et al. Risk factors for bronchiolitis-associated deaths among infants in the United States. PediatrInfect Dis J. 2003;22:483–489.

Managed care payers should be cognizant of the potentialramifications of severe RSV disease in infants. Developing aproactive RSV management strategy can help improve healthoutcomes and reduce unnecessary hospital resource use.

ReferencesAAP (American Academy of Pediatrics). Respiratory syncytial virus.

In: Pickering LK, ed. Redbook: 2006 Report of the Committee onInfectious Diseases. 27th ed. Elk Grove Village, Ill.: AmericanAcademy of Pediatrics; 2006:560–566.

Anderson LJ, Parker RA, Strikas RA, et al. Day-care center attendanceand hospitalization for lower respiratory tract illness. Pediatrics.1988;82:300–308.

Arnold SR, Wang EEL, Law BJ, et al. Variable morbidity of respira-tory syncytial virus infection in patients with underlying lungdisease: a review of the PICNIC RSV database. Pediatr Infect DisJ. 1999;18:866–869.

Boyce TG, Mellen BG, Mitchel EF Jr, et al. Rates of hospitalization forrespiratory syncytial virus infection among children in Medi-caid. J Pediatr. 2000;137:865–870.

Carbonell-Estrany X, Quero J, and the IRIS Study Group. Hospital-ization rates for respiratory syncytial virus infection in pre -mature infants born during two consecutive seasons. PediatrInfect Dis J. 2001;20:874–879.

Carroll KN, Gebretsadik T, Griffin MR, et al. Maternal asthma andmaternal smoking are associated with increased risk of bronchi-olitis during infancy. Pediatrics. 2007;119:1104–1112.

Steps to creating an effective RSV program for high-risk infantsA managed care analysis by Norman White, MDMedical Director, Presbyterian Health Plan, Albuquerque, N.M.

Through the use of successivequality-improvement cycles,Presbyterian Health Plan

(PHP) has evolved an effectiveprocess to reduce the impact ofRSV disease in the high-risk infant population.

Timely and appropriateidentification of high-riskinfants, particularly infantsborn 35 weeks gestationand less who have two ormore documented risk fac-tors, is the first step andrequires the participationof the neonatalogy treat-ment team, including the physi-cian, nurse, pharmacist, and dis-charge planner, as well as the NICUteam and hospital case managers.RSV management begins prior to

hospital discharge and continuesthroughout an infant’s first RSVseason.

The use of standardized forms,originating in contracted NICUs

and primary care offices, isan important component ofPHP’s RSV managementprocess. Initial informationabout a high-risk infant isconveyed to the primarycare provider prior to out-patient follow-up usingcommon forms that havebeen developed in collabo-ration with local pediatric

clinicians and health care insurers.Continuity of care is reinforced

by the PHP program coordinatorand home health agencies thatwork with the identified infants

and their parents or caregivers tofollow through with the RSV man-agement program during the firstRSV season.

The program’s season is deter-mined by the historical time framefor RSV occurrence in New Mexico,together with current season infor-mation provided by the local virol-ogy lab in Albuquerque. The antici-pated onset of the season isNovember 1, while monitoring ofcurrent data allows for the abilityto initiate program activity soonerif warranted. Similarly, the end ofthe RSV season is monitored forthe decreasing incidence of RSVisolates, with termination of theprogram typically at the end ofApril.

Norman White,MD

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Panozzo CA, Fowlkes AL, Anderson LJ. Variation in timing of respi-ratory syncytial virus outbreaks. Lessons from National Surveil-lance. Pediatr Infect Dis J. 2007;26:S41–S45.

Rossi GA, Medici MC, Arcangeletti MC, et al. Risk factors for severeRSV-induced lower respiratory tract infection over four consec-utive epidemics. Eur J Pediatr. 2007;166:1267–1272. Epub 2007Feb 17.

Shay DK, Holman RC, Newman RD, et al. Bronchiolitis-associatedhospitalizations among U. S. children, 1980–1996. JAMA. 1999;282:1440–1446.

Shay DK, Holman RC, Roosevelt GE, et al. Bronchiolitis-associatedmortality and estimates of respiratory syncytial virus-associ-ated deaths among US children. 1979–1997. J Infect Dis.2001;183: 16–22.

Sigurs N, Gustafsson PM, Bjarnason R, et al. Severe respiratory syn-cytial virus bronchiolitis in infancy and asthma and allergy atage 13. Am J Respir Crit Care Med. 2005;171:137–141.

Simoes EA, King SJ, Lehr MV, Groothuis JR. Preterm twins andtriplets: a high-risk group for severe respiratory syncytial virusinfection. Am J Dis Child. 1993;147:303–306.

Stein RT, Sherrill D, Morgan WJ, et al. Respiratory syncytial virus inearly life and risk of wheeze and allergy by age 13 years. Lancet.1999;354:541–545.

Thompson WW, Shay DK, Weintraub E, et al. Mortality associatedwith influenza and respiratory syncytial virus in the UnitedStates. JAMA. 2003;289:179–186.

Von Linstow ML, Hogh M, Nordbo SA, et al. A community study ofclinical traits and risk factors for human metapneumovirus andrespiratory syncytial virus infection during the first year of life.Eur J Pediatr. 2008;167:1125–33. Epub 2008 Jan 3.

Wang EL, Law BJ. Respiratory syncytial virus infection in pediatricpatients. Semin Pediatr Infect Dis. 1998;9:146–153.

Wilkesmann A, et al. Hospitalized children with respiratory syncytialvirus infection and neuromuscular impairment face anincreased risk of a complicated course. Pediatr Infect Dis J.2007;26:485–491.

Yeung CY, Hobbs JR. Serum-γG-globulin levels in normal, prema-ture, post-mature, and “small-for-dates” newborn babies.Lancet. 1968;1(7553):1167–1170.

Horn SD, Smout RJ. Effect of prematurity on respiratory syncytialvirus hospital resource use and outcomes. J Pediatr. 2003;143(5suppl):S133–S141.

Lanari J, Giovannini M, Giuffre L, et al. Prevalence of respiratorysyncytial virus infection in Italian infants hospitalized for acutelower respiratory tract infections and association between respi-ratory syncytial virus infection risk factors and disease severity.Pediatr Pulmonol. 2002;33:458–465.

Langston C, Kida K, Reed M, Thurlbeck WM. Human lung growth inlate gestation and in the neonate. Am Rev Respir Dis. 1984;129:607–613.

Law BJ, Langley JM, Allen U, et al. The Pediatric Investigators Collab-orative Network on Infections in Canada study of predictors ofhospitalization for respiratory syncytial virus infection forinfants born at 33 through 35 completed weeks of gestation.Pediatr Infect Dis J. 2004;23:806–814.

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Leader S, Kohlhase K. Recent trends in severe respiratory syncytialvirus (RSV) among US infants, 1997 to 2000. J Pediatr. 2003a;143(5 suppl):S127–S132.

Leader S, Yang H, DeVincenzo J, et al. Time and out-of-pocket costsassociated with respiratory syncytial virus hospitalization ofinfants. Value Health. 2003b;6:100–106.

Marbury MC, Maldonado G, Walter L. Lower respiratory illness,recurrent wheezing, and day care attendance. Am J Respir CritCare Med. 1997;155:156–161.

Martin JA, Hamilton BE, Sutton PD, et al. Division of Vital Statistics.Births: final data for 2005. Natl Vital Stat Rep. 2007;56:1–104.

McConnochie KM, Roghmann KJ. Parental smoking, presence ofolder siblings, and family history of asthma increase risk ofbronchiolitis. Am J Dis Child. 1986;140:806–812.

McLaurin KK, Leader S. Growing impact of RSV hospitalizationsamong infants in the US, 1997–2002. Abstract 936. Presented at:Pediatric Academic Societies Annual Meeting, May 14–17, 2005,Washington.

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infections. Report prepared for MedImmune, LLC, Gaithers-burg, Md. February 2007.

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Disclosures: Doris Makari, MD, is an employee of MedImmune.J. Michael Hoopes, PharmD, is an employee of MedImmune.He is also a member of the American Society of Health-SystemPharmacists and the Drug Information Association.Norman White, MD, is a Medical Director with PresbyterianHealth Plan, Albuquerque, New Mexico. He reports no finan-cial arrangements or affiliations that may constitute a conflictof interest with his commentary.

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2752 12/08 © 2008 MedImmune, LLC

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