Examining the Relationship Between Chronic Pain and Health-Related Quality of Life Among Older Canadian Adults with Disability Kristina Zawaly, B.A., B.Sc. & M.Sc. University of Manitoba

Outline Acknowledgment Background Study Objectives Conceptual Framework Research Methods Descriptive Results Results from Multivariate Analyses Summary of Findings Strengths and Limitations Conclusions and Implications of Research Findings

Acknowledgments Advisor: Shahin Shooshtari, Ph.D. University of Manitoba Committee Members: Nancy Hansen, Ph. D., Verena Menec, Ph.D. and Ian Clara Ph.D. University of Manitoba Funding: The University of Manitoba Centre on Aging (2011, Graduate Fellowship) & The University of Manitoba Research Data Centre (2011, Graduate Fellowship) & Research Data Centre (2012, Travel Grant)

Background With the aging of the Canadian population, there will be a significant increase in the number of individuals, who will be aging with/into disability. Pain related disability is common affecting approximately 27% of the older Canadian population (Ramage-Morin, 2008). Prevalence of chronic pain increases with age: [Males: 15.2%; Females: 19.2% ] [Males: 20.6%; Females: 24.8%] 75+ [Males: 28.8%; Females: 38.5%] (Statistics Canada, 2011b) Previous research clearly shows that chronic pain is associated with reduced health-related quality of life (HRQoL) (Picavet & Hoeymans, 2004; Kim et al., 2005; Lamé, Peters, Vlaeyen, Kleef & Patijn, 2005 ).

Gaps in the Literature Prevalence of chronic pain among older Canadian adults with disability; The impact of chronic pain on HRQoL in older Canadian adults with disability

Study Objectives 1) To estimate the prevalence of chronic pain among older Canadian adults with disability. 2) To examine the relationship between chronic pain and HRQoL among older Canadian adults with disability. 3) To assess if there is a dose-response relationship between chronic pain and HRQoL among older Canadian adults with disability.

ICF Framework

Conceptual Framework

Research Methods Study Design: Analysis of cross-sectional data Data Source: 2006 Participation and Activity Limitations Survey (PALS) - Adult survey Post-censual survey Conducted by Statistics Canada Target population: Canadian adults (15+) and children (<15) with disability living in 10 Canadian provinces and 3 territories. Purpose: To collect information on the prevalence of various disabilities, support for persons with disabilities, their employment profile, income and participation in society. (Statistics Canada, 2009)

Research Methods Study Sample : Individuals who were at least 55 years of age at the time of the survey who reported “Yes” to having a disability. Study Population: The number of participants in the study sample are representing 2,582,500 of all Canadians 55+ who experience disability.

Study Measures  Dependent Variables (DV):  To address objective #1: Chronic pain  To address objectives #2 & #3: HRQoL  Independent Variables:  Chronic pain  Sociodemographic characteristics (Age, sex, education, marital status, total household income and social network);  Disability measures (Type of disability, severity of disability, and onset of disability).

Data Analysis Population weights were applied and weighted frequencies were used to describe the target population and their characteristics. Bivariate analyses (t-test and chi-square test) were used to examine the cross-sectional relationship between study variables and chronic pain as well as HRQoL. Multiple logistic regression modeling was used to examine the independent effect of chronic pain in relation to HRQoL controlling for the effects of all the other study factors. Bootstrap weights were applied using SUDAAN software to estimate variance and 95% confidence intervals.

Results

Descriptive Results Study Population: Canadian Population with Disability Aged 55+, PALS 2006

Variablesn% Total2,582, Age 55 to 64824, to 74739, ,018, Sex Female1,451, Male1,130, Income in Canadian Dollars 0 – 22,445550, , ,415738, ,416 – 72,040673, ≥72,041618, Marital Status Living Alone1,167, Living With a Partner1,414, Variablesn% Education No High School Diploma533, High School Diploma245, Higher than High School Diploma754, Chronic Pain No 804, Less Severe 1,162, More Severe 579, HRQoL Positive1,346, Negative1,040,

Variablesn% Friends None 191, One to Two 418, Three to Five 617, Six to Ten 388, to , More than , On Set of Disability Birth to 18 years 148, to 54 years 804, to 64 years 551, to 74 years 497, years 428, Severity of Disability Mild to moderate 1,539, Severe to very severe 1,043, Variablesn% Type of Disability Agility 1,871, Communication 224, Developmental 26, Emotional 204, Hearing 966, Learning 212, Memory 261, Mobility 1,947, Seeing 515, Unknown Disability 68,

Bivariate Results Description of Study Population by Chronic Pain Study Population: Canadian Population with Disability Aged 55+, PALS 2006

Variables Severe Chronic Pain Less Severe Chronic Pain No Chronic PainX2X2 p Value %% Sex *** Female Male Age *** 55 to to Income in Canadian Dollars ≥ HRQoL *** Positive Negative *** p<0.001, **p<0.01, *p<0.05 Table (1): Chronic Pain by Sociodemographic and Disability Characteristics

Variables Severe Chronic Pain Less Severe Chronic Pain No Chronic PainX2X2 p Value %% Education ** Less than high school High school Moe than high school Friends ** None One to Two Three to Five Six to Ten to More than Onset of Disability ** Birth to 18 years to 54 years to 64 years to 74 years years Severity of Disability ** Mild to moderate Severe to very severe *** p<0.001, **p<0.01, *p<0.05

Bivariate Results Description of Study Population by HRQoL Study Population: Canadian Population with Disability Aged 55+, PALS 2006

Table (2): HRQoL by Sociodemographic and Disability Characteristics VariablesNegative HRQoLPositive HRQoLX2X2 p Value % Sex Female Male Age to to Income in Canadian Dollars *** 0 – 22, ,446 – 42, ,416 – 72, ≥ 72, Marital Status ** Living Alone Living With a Partner ***p<0.001, **p<0.01, *p<0.05

VariablesNegative HRQoLPositive HRQoLX2X2 p Value % Education Less than high school High school More than high school Friends *** None One to Two Three to Five Six to Ten to More than ***p<0.001, **p<0.01, *p<0.05

VariablesNegative HRQoLPositive HRQoLX2X2 p Value % Onset of Disability to 1 years to 5 years to 10 years to 15 years to 20 years plus years Severity of Disability Mild to moderate *** Severe to very severe ***p<0.001, **p<0.01, *p<0.05

Multiple Logistic Regression Model Predictors of HRQoL Study Population: Canadian Population with Disability Aged 55+, PALS 2006

VariablesAOR95% CIp Value Sex Female0.69**( ) Male1.00( )- Age 55 to ( )- 65 to ( ) ( ) Income in Canadian Dollars 0-22, *( ) ,446-42, **( ) ,416-72, ( ) ≥ 72, ( )- Marital Status Living Alone1.00( )- Living With a Partner1.12( ) ***p<0.001, **p<0.01, *p<0.05 Table (3): Socio-demographic Predictors of Negative HRQoL

VariablesAOR95% CIp Value Friends None0.97( ) One to Two1.04( ) Three to Five0.88( ) Six to Ten0.94( ) to *( ) More than ( )- Onset of Disability Birth to 18 years1.00( )- 19 to 54 years1.02( ) to 64 years1.28( ) to 74 years1.25( ) years1.00( ) Severity of Disability Mild to moderate1.00( )- Severe to very severe 1.51**( ) ***p<0.001, **p<0.01, *p<0.05

VariablesAOR95% CIp Value Agility Yes1.85***( No1.00( )- Communication Yes1.19( ) No1.00( )- Developmental Yes1.04( ) No1.00( )- Emotional Yes1.33( ) No1.00( )- Hearing Yes1.03( ) No1.00( )- Learning Yes1.56( ) No1.00( )- ***p<0.001, **p<0.01, *p<0.05

VariablesAOR95% CIp Value Memory Yes1.35( ) No1.00( )- Mobility Yes 2.26***( ) No1.00( )- Seeing Yes 1.37*( ) No1.00( )- Unknown Disability Yes1.00( ) No1.00( )- Chronic Pan More Severe 3.43***( )0.000 Less Severe1.39*( ) No1.00( )- ***p<0.001, **p<0.01, *p<0.05

Summary of Findings The oldest old Canadian adults reported less chronic pain than did the youngest old adults (X 2 =13.51; p=0.0000). Those affected by chronic pain reported significantly poorer HRQoL compared to those who did not report chronic pain (X 2 =207.27; p=0.0000). The age of onset and the type of disability were significantly associated with reported chronic pain.

Summary of Findings (Con’t) Females reported higher levels of chronic pain, but controlling for the effects of all the other factors, they had significantly lower odds of reporting negative HRQoL [AOR=0.69 (95% CI: ); p=0.0024]. Those with agility and mobility disability reported high levels of chronic pain and high levels of negative HRQoL than those who reported no mobility or agility disability [AOR=1.85 (95% CI: ); p=0.0000] and [AOR=2.26 (95% CI: ); p= respectively].

Strengths and Limitations This research used a national level sample of Canadians, with the ONLY national level data available for individuals with disabilities. HRQoL was measured using a single self-rated health question as it is a better measure of HRQoL for individuals with disabilities. The conceptual framework, used based on the ICF, is the best attempt available in the literature to bring the social and medical model of disability together. PALS 2006 was a cross-sectional survey, where information was obtained from individuals at one single point in time ONLY. No causality conclusions could be made. Proxy responding was allowed. This may have introduced some bias in the results, especially for HRQoL or chronic pain measures, and especially for those with limited communication abilities. All questions in PALS 2006 were self reports and therefore there is a potential risk for recall biase.

Implications of Findings Practice: The study findings highlight the importance of “proper pain assessment and management” among older adults with disability (both men and women), especially for those with limited communication skills. Policy: In Canada the collection of information on individuals with disabilities has been discontinued. National level data of longitudinal nature is needed to examine trends over time, and to inform policy and practice. Research: Further research is needed to examine the impact of chronic pain on HRQoL and other outcomes (e.g., social participation), using longitudinal data. study. Given the observed sex differences in the reported rates of chronic pain and HRQoL, it is important to explore sex differences, when examining chronic pain and HRQoL association.

References Kim, J., Henderson, R. A., Pocock, S. J., Clayton, T., Sculpher, M. J., & Fox, K. A. (2005). Health-related quality of life after interventional or conservative strategy in patients with unstable angina or non-ST-segment elevation myocardial infarction: one-year results of the third Randomized Intervention Trial of unstable Angina (RITA-3). Journal of the American College of Cardiology, 45(2), Lamé, I. E., Peters, M. L., Vlaeyen, J. W., Kleef, M., & Patijn, J. (2005). Quality of life in chronic pain is more associated with beliefs about pain, than with pain intensity. European Journal of Pain, 9(1), Picavet, H., & Hoeymans, N. (2004). Health related quality of life in multiple musculoskeletal diseases: SF-36 and EQ-5D in the DMC 3 study. Annals of the Rheumatic Diseases, 63(3), Ramage-Morin, P. L. (2008). Chronic pain in Canadian seniors. Health Reports (Catalogue number X). Statistics Canada (2011b). Disability in Canada: A 2006 Profile. (Catalogue number HS64-11/2010E-PDF). Statistics Canada (2009). Participation and Activity Limiation Survey Public Use Microdata file User Guild. (Catalogue number: 89M0023XCB2006). World Health Organization (WHO). (2001). International Classification of Functioning, Disability and Health: ICF. Geneva, Switzerland.