Objectives: To investigate the impact of urinaryincontinence (UI) on health-related quality of life(QOL), as measured by the Medical Outcomes StudyShort Form-36 (SF-36) and to compare UI and non-UI elderly Medicare beneficiaries enrolled in managedcare plans on the prevalence of depression andself-rated health.
Methods: After excluding beneficiaries youngerthan 65 years old, a total of 141 815 completed surveyswere used for analysis. The survey included 1question on difficulty in controlling urination, 3 questionson depression, 3 questions on health, a seriesof questions regarding comorbid medical conditions,and the SF-36. Self-rated health, prevalence ofdepression, and scores in each domain of QOL werecompared between UI and non-UI groups.
Results: Overall, the prevalence of UI was 24.7%(20.9% in men, 27.5% in women). The UI groupwas about twice as likely to feel depressed as thenon-UI group. The UI group also rated their healthmore negatively. Compared with continent respondents,those who were incontinent had lower standardizedscores on all 8 subscales of SF-36 as wellas 2 summary scores. Results from multiple regressionsindicated that UI had a significantly negativeimpact on all aspects of QOL after adjusting forcomorbidities and demographic differences.
Conclusion: Findings indicate that elderlypatients with UI are more depressed and have worseperceived health. On certain domains of QOL, thenegative impact of UI even surpasses that of othersevere comorbidities.
(Am J Manag Care. 2005;11:S103-S111)
Urinary incontinence (UI), or theinvoluntary loss of urine, can occurat any age, but is especially commonin elderly women.1,2 UI has been estimatedto affect 20% to 33% of adults3,4 or 11% to55% of the elderly,1,2,5-8 depending on the ageof the subjects, the healthcare setting wherethe study was performed, the definition of UIemployed, and, potentially, the format of thequestions being asked about UI. The prevalenceof UI in older women is approximately2 times that of older men.1,6 Compared withthe elderly living at home, those residing innursing homes or hospitals also have a higherprevalence of UI,1 which may be one ofthe contributing factors to institutionalization.Despite the high estimate of prevalence,as many as 50% of all cases of UI maynot have been reported, because individualswith UI do not always seek medical help.3,9-11
Current treatments for UI include behavioral(eg, bladder training, fluid manipulation,scheduled toileting, pelvic muscleexercises), pharmacological, and surgicalinterventions, used either alone or in combination.11-13 Behavioral techniques are nowcurrently recommended as first-line therapyin the treatment of UI.14,15 Behavioral interventionsare usually relatively inexpensiveand easy to implement, but the effectivenesschiefly depends on the patient's adherence.16 When nonpharmacologic interventionshave failed, drug therapy can be anoption.11 The effectiveness of older drugs,such as immediate-release (IR) oxybutynin,is not satisfactory, partly because of poorcompliance as a result of adverse events(AEs).17 The new generation of pharmacologicaltreatments, such as extendedrelease(ER) tolterodine and transdermaloxybutynin, provide better or comparableefficacy, but with fewer AEs.18-21 Althoughsurgical interventions are used in only themost refractory cases of urge UI, they aremore commonly used in the treatment ofstress UI.11
Because UI may cause social isolation,loss of sexual function, and other psychosocialproblems,3,22,23 it could have significantimpact on patients' psychosocial well-beingand quality of life (QOL). Studies haveshown that patients suffering with UI aremore depressed,24,25 psychologically distressed,26 emotionally disturbed,27 andsocially isolated.27 Moreover, compared withcontinent individuals, those patients with UIalso have higher levels of anxiety,28 lowerQOL,27 and poorer life satisfaction.25 Theseverity of UI is also correlated with degreesof mental distress, social restrictions, andrestricted activities.3,23 As a result, UI has anadverse effect on patients' daily lives andcould become a barrier for normal socialfunction.27
Diagnostic and Statistical Manual
of Mental Disorders, Third Edition (DSMIII).
Previous studies have indicated thatdepression was common in adults with UI. Astudy using the Geriatric Depression Scaleon homebound elders with UI found that upto 50% of the elderly patients had significantdepressive symptomatology.29 Another studyfound that those patients with UI were morelikely to have major depression than thosewithout UI (odds ratio [OR] = 4.5; 95% confidenceinterval [CI] = 2.3-8.8), as assessedusing the 24 Although UI is associated with depression,the causal pathway from UI todepression is not entirely clear.
Several generic and disease-specificinstruments have been used to assess theQOL of adults with UI. Although UI-specificinstruments, such as the IncontinenceImpact Questionnaire30 and the IncontinenceQuality of Life Instrument,31 tend tobe more sensitive to the unique impact ofUI, generic measures permit the comparisonamong different populations or interventions.32 One study using the Sickness ImpactProfile, a generic health status instrument,found that the QOL of community-livingwomen was adversely affected by UI considerably.33 Another study using the NottinghamHealth Profile Questionnaire, a generichealth status instrument as well, indicatedthat women with UI were more emotionallydisturbed and socially isolated than thosefrom the age-matched control group withoutUI.27 The literature also suggests thatpatients with urge UI and mixed UI are morelikely to suffer with depression and poorerQOL than those with stress UI.34-36Among the generic measures of QOLinstruments, the Medical Outcome StudyShort Form-36 (SF-36) is most widely usedand well known in healthcare research. Itcontains 1 item assessing health transitionand 35 items assessing 8 domains of healthstatus—physical functioning (PF), role limitationsas a result of physical problems (RP),bodily pain (BP), general health perceptions(GH), vitality (VT), social functioning (SF),role limitations as a result of emotionalproblems (RE), and mental health (MH).37These 8 subscales are also used to generate2 health summary scores, the physical componentsummary (PCS) and the mentalcomponent summary (MCS).38 Two studiesshowed that SF-36 scores of the patientswith UI were lower in all 8 domains comparedwith the general population or thecontrol group.39,40 However, O'Conor andcolleagues found that patients with urge ormixed UI had significantly lower scores inonly 5 of 8 dimensions (ie, PF, SF, RE, RP,VT) compared with the general US population,17 and Kutner and colleagues showedthat UI significantly affected GH, RP, andRE, but not SF.41 In summary, previous studiesare inconsistent regarding the specificdomains of QOL affected by UI, but itappears that numerous domains are affected.
Previous studies of QOL and UI usuallyrecruited subjects only from a particularsetting, such as nursing homes,7,8 communities,5,23,41 or hospitals,22 and they have alimited sample size, which ranges from severaldozen to several hundred persons.8,17,22,23,28,33,39-41 Therefore, the overallprevalence and impact of UI on the US elderlypopulation remains unknown. The primarypurpose of this study was to investigatethe prevalence of UI among the elderly usinga sample of Medicare managed careenrollees. The self-rated health and the presenceof depression in the UI and non-UI subjectswere also compared.
The Medicare Health OutcomesSurvey (HOS), formerly titled Healthof Seniors, was the first large-scale subject-basedoutcomes measure funded by theCenters for Medicare and Medicaid Servicesto assess the quality of care provided toMedicare beneficiaries enrolled in managedcare.42 A random sample was selected andsurveyed every spring, and the same respondentswere surveyed again 2 years later. Thefirst baseline cohort was surveyed in May1998, which was composed of 279 135 Medicarebeneficiaries enrolled in 269 Medicare+ Choice Organizations from 287 marketareas.42 A combination of mail and phonesurveys was used to collect the data. Areturned survey was considered "complete"if at least 80% of the response items werecompleted and 3 specific questions aboutthe respondent's overall health status wereanswered. The final response rate was about60%. More detailed descriptions about thedata collection process were reported elsewhere.43 In this study, only those respondentsaged 65 years and older were includedin the analyses.
The HOS is a self-administered surveythat includes several questions on demographics,health status, depression, comorbidmedical conditions, and the SF-36. The3 health status questions focus on the subject'sgeneral health, health comparedwith 1 year ago, and health compared withtheir peers. Each question was measuredon a 5-point scale from 1 (excellent/muchbetter now) to 5 (poor/much worse now).Depression was measured by 3 yes/no questions:(1) In the past year, have you had 2weeks or more during which you felt sad,blue, or depressed, or when you lost interestor pleasure in things that you usually caredabout or enjoyed?; (2) In the past year, haveyou felt depressed or sad much of the time?;and (3) Have you ever had 2 years or morein your life when you felt depressed or sadmost days, even if you felt okay sometimes?
The SF-36 is a widely used instrument inhealth services research for assessing health-relatedQOL. The validity and reliability ofthis instrument has been established formeasuring QOL in large populations of bothhealthy and diseased individuals.44-46 Scoresof the 8 dimensions of SF-36 range from zero(the worst QOL) to 100 (the best QOL). Tocompare with the general US population, thezero to 100 scores are also transformed tostandardized scores (mean of 50, standarddeviation of 10), with a score of 50 representingthe national average for a given scaleor summary score. In this study, the standardizedscores were used.
The question, "Do you have difficultycontrolling urination?" in the HOS surveywas used to identify respondents sufferingfrom UI. Respondents were classified as theUI or non-UI group depending on whetherthey answered "yes" or "no" to the samequestion; persons denying the conditionwere unable to be distinguished. A checklistof various comorbidities was included in thesurvey. Eleven common medical conditionsthat have been reported to have adverseeffects on QOL47 were included in this studyas covariates; they are hypertension, anginapectoris, congestive heart failure, myocardialinfarction, other heart conditions,stroke, emphysema/asthma/chronic obstructivepulmonary disease (COPD), arthritis ofthe hip/knee, arthritis of the hand/wrist,cancer, and diabetes.
The chi square testwas used to compare the distributions ofdemographic characteristics, depression,comorbidities, and perceived health statusamong the UI group and non-UI group. Two-tailedStudent's -test was used to compareeach domain of the SF-36 scores betweenthe 2 groups.
A multiple regression model was conductedfor each of the 8 domains and the 2 summaryscores of the SF-36. The impact of UIon the QOL scores was estimated, after controllingfor age, sex, race, marital status,education level, and the 11 common medicalconditions listed above. All analyses wereconducted with SPSS for Windows (Version11.0). Findings were considered statisticallysignificant if <.05.
Characteristics of Subjects.
Of the141 815 respondents who completed thesurvey, 60.3% were between the ages of 65 to74 years old, 90.3% were Caucasian, 58%were women, and 59.1% were married. Onethird (36.0%) had graduated from highschool or held a General Educational Developmentdiploma, and another one third(37.3%) had at least some college educationor a 2-year college degree.
About 2.1% (2996) of the subjects did notanswer the UI question. Of the remainingsubjects, 34 292 (24.7%) reported having difficultycontrolling urination. The prevalenceof UI among men and women was 20.9% and27.5%, respectively. Compared with the non-UI group, the UI group was more likely to bewomen, Caucasian, older than 74 years,unmarried, and had less than a high schooleducation (Table 1). The distribution ofcomorbidities differed significantly betweenUI and non-UI groups (<.001). Patientswith UI tended to have more comorbid medicalconditions than those without UI.
UI and General Health.
Generally, patientswith UI had a more negative view ontheir health. About 65% of the UI group and80% of the non-UI group rated their generalhealth as good or better. Approximately 70%of the UI group rated their health as good orbetter than their peers compared with 85% inthe non-UI group. In addition, 25% of thosewith UI perceived their health as decliningcompared with 1 year ago, whereas only 13%of the continent respondents did so.
UI and Depression.
Depression was moreprevalent in the UI group. Respondents withUI were about twice as likely to report beingdepressed as the non-UI group. Approximately28% of the UI population feltdepressed or lost interest for 2 weeks ormore in things that they usually enjoyedcompared with only 15.4% in the non-UIgroup. About 18% of persons with UI feltdepressed or sad much of the time in thepast year, whereas less than 10% of continentrespondents felt the same way.Similarly, 17.7% of persons with UI hadexperienced depression for 2 or more yearscompared with 9.7% in the non-UI group.
Impact of UI on QOL.
As standardizedscores were used, a score of 50 representsthe national average for both the subscalescores and summary scores. A score of 10points above or below 50 represents a differenceof 1 standard deviation from thenational average.
As shown in Table 2, UI had a significantimpact on QOL. Mean scores for UI were alllower than 50; this suggests that the UIgroup scored lower than the general US populationon all domains of the SF-36. Thelargest differences between UI group andthe general US population were observed inthe PF and role-physical domains (Table 2).The UI group had significantly lower scoresthan the non-UI group in all of the 8 subscalesand in the 2 component summaries(<.001), indicating that persons with UIhave relatively poorer QOL compared withthose who are continent (Table 2). On average,the incontinent elderly patient scored 6.6and 3.9 points lower than the continent groupin PCS and MCS, respectively. The adverseimpact of UI on the SF-36 domain scoresranged from 4.0 points in MH to 6.7 points inRP compared with respondents without UI.
After adjusting for age, sex, race, maritalstatus, education level, and other comorbidities,UI remained a significant predictor ofall domains of SF-36 and 2 summary scores(<.05). Results from multiple regressionindicated that the presence of UI reducedPCS and MCS by 3.7 and 3.0 points, respectively.In the 8 domains of SF-36, the UI groupscored 2.9 to 4.2 points less than the non-UIgroup. The 2 for the 10 regression modelsranged from .07 for MCS to .32 for PCS.
The standardized regression coefficientsallow us to compare the relative impact ofindependent variables; the larger the coefficient,the greater the impact of a variable onthe outcome. As shown in Table 3, among allthe medical conditions, UI had the largeststandardized coefficient (in absolute value)on VT, SF, RE, and MH scales. In otherwords, UI had a relatively greater impact onthese domains of QOL than other comorbidities.Moreover, the adverse impact of UI onPF and GH was the second highest, next onlyto emphysema, asthma, COPD and arthritisof the hip and knee. The adverse impact of UIon bodily pain was only second to arthritis ofthe hand and wrist and hip and knee.
This is the first study investigating theprevalence of UI among the elderly Medicarepopulation enrolled in managed care plans.In this large random sample, about onefourth of the population reported havingdifficulty controlling urination. Moreover,women were significantly more likely thanmen to report suffering with UI, which isconsistent with the results of previousstudies.1,6
This study shows that elderly patientswith UI had a worse perception of health andwere more likely to be depressed. However,these associations could be because respondentswith UI were indeed less healthy as aresult of greater comorbidities. Similar toprevious studies on UI and depression, thisstudy is based on cross-sectional data andcannot provide evidence on the temporal orcausal relationships between UI and depression.Prospective studies are needed in thefuture to delineate the causality between the2 health conditions.
Compared with other medical conditionsincluded in our models, UI has a more substantialimpact on both physical and mentaldimensions of QOL. UI decreases MCSscores more than other medical conditions.This was not surprising, given the plethoraof psychosocial problems associated withthis disease condition. It is notable that theimpact of UI on PCS was only secondaryto that of emphysema/asthma/COPD andarthritis of the hip/knee. The impact of UIon the pain domain of QOL further exemplifieshow a medical condition couldaffect a person's QOL, even on thoseunanticipated domains. A medical conditionthat does not directly cause muchpain may, nonetheless, exacerbate otherunderlying conditions and intensify theperception of pain.
As the population in the United Statesages and the proportion of elderly aged 65years and older grows from 12.7% in 1999 to18.5% in 2025,43 there is an urgent need foreffective and efficacious management strategiesfor chronic degenerative diseases. Asbaby boomers (those aged 39-57 years in2003) grow older, the demand for seniorcare will increase rapidly during the 2010 to2030 period. The goal of healthy agingshould be to not only extend life expectancy,but improve QOL as well. From a managedcare perspective, the undeniable impact of a"benign" condition, such as UI on physicaland MH, has policy implications. Futurestudies need to focus on whether early diagnosisand more aggressive interventions forUI could reduce long-term healthcare costs,decrease disease burden, and increase QOLand patient satisfaction of health-planenrollees.
There are a few limitations to this study.The presence or absence of UI and otherhealth conditions was self-reported. Theextent to which the information was consistentwith medical records is unknown,although based on the results of a previousstudy, the accuracy is generally satisfactorywith a few exceptions.48 In addition, the surveydata used in this study were obtainedfrom the elderly Medicare beneficiariesenrolled in managed care plans; therefore,these survey findings may not be generalizedto a younger population or the elderly coveredby a different type of health plan. As aresult of data limitations, it was not possibleto differentiate the types of incontinence inrespondents, although previous studies indicatedthat QOL of the elderly with stressincontinence was less affected than thosewith UI.27,33,39
Our results suggest that UI is prevalentand can have significant impact on both thephysical and mental health of the elderlypopulation. This is an important epidemiologicaland clinical finding that suggests furtherstudy and action, both by clinicians andpolicymakers. Some incontinent individualsdo not seek medical help because theyeither are not aware that effective treatmentsare possible, consider it as a naturalaging process, or are too ashamed to mentionit to their healthcare providers.3,49 As aresult, only one quarter to one half of individualsactually sought medical help.12Healthcare providers need to be sensitive tothese deterrents and identify better ways ofevaluating and discussing UI with theirpatients. In addition, clinicians can play animportant role in educating patients abouttheir health condition, treatment options,and disease management. Several treatmentchoices are now available with greater effectivenessand feasibility, and with increasedawareness, proper differential diagnosis, andbetter screening of UI, health providers canseize opportunities to significantly improvethe QOL of the elderly population along thisdimension.
The authors wish to thank Pfizer/PharmaciaCorporation for partial financial supportfor this work. We also wish to acknowledgeZhanna Jumadilova, MD, MBA, of Pfizer's USOutcomes Research for review of a previousversion of this manuscript.
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