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

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)

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: 55-64 [Males: 15.2%; Females: 19.2% ]65-74 [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 ).

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.

Study Design: Analysis of cross-sectional data

Data Source: 2006 Participation and Activity Limitations Survey (PALS) - Adult survey

Post-censual surveyConducted 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)

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).

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 ResultsStudy Population: Canadian Population with Disability

Aged 55+, PALS 2006

Variables n %

Total 2,582,500 100

Age55 to 64 824,920 31.9065 to 74 739,500 28.60

75+ 1,018,090 39.40

Sex

Female 1,451,860 59.60

Male 1,130,640 40.40

Income in Canadian Dollars0 – 22,445 550,550 21.3022,446 - 42,415 738,150 28.6042,416 – 72,040 673,440 26.10 ≥72,041 618,010 24.10Marital Status

Living Alone 1,167,88

0 45.20Living With a Partner

1,414,160 54.80

Variables n %

EducationNo High School Diploma 533,290 34.80

High School Diploma 245,830 16.00Higher than High School Diploma 754,680 49.20

Chronic Pain

No 804,504 31.37

Less Severe 1,162,790 45.34

More Severe 579,170 23.29

HRQoL

Positive 1,346,520 56.40

Negative 1,040,020 43.60

Variables n %

Friends

None 191,020 9.90

One to Two 418,030 21.80

Three to Five 617,650 32.20

Six to Ten 388,060 20.20

11 to 20 165,260 8.60More than 20 140,700 7.30On Set of DisabilityBirth to 18 years 148,880 6.1219 to 54 years 804,680 33.1055 to 64 years 551,640 22.6965 to 74 years 497,590 20.47

75+ years 428,040 17.61Severity of DisabilityMild to moderate 1,539,220 59.0Severe to very severe 1,043,290 40.40

Variables n %Type of DisabilityAgility

1,871,740 72.50Communication

224,100 8.70Developmental

26,470 1.00Emotional

204,770 8.00Hearing

966,420 37.50Learning

212,210 8.20Memory

261,760 10.20Mobility

1,947,000 75.40Seeing

515,270 20.00Unknown Disability

68,170 2.60

Bivariate ResultsDescription of Study

Population by Chronic Pain

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

VariablesSevere

Chronic Pain

Less Severe Chronic Pain No Chronic Pain X2 p Value

% % %Sex 21.08 0.0000***Female 24.7 48.7 26.6Male 21.5 41.1 37.5

Age 13.51 0.0000***

55 to 64 28.0 48.2 23.865 to 74 21.2 48.4 30.575 + 21.0 40.8 38.2Income in Canadian Dollars 0.61 0.6716

0 - 2245 25.1 44.7 30.222446 - 42415 23.3 43.8 32.942416 - 72040 23.1 45.6 31.4≥ 72041 21.9 47.5 30.7HRQoL 207.2

7 0.0000***

Positive 10.8 47.1 42.1Negative 38.8 42.3 18.9

***p<0.001, **p<0.01, *p<0.05

Variables Severe Chronic Pain

Less Severe Chronic Pain No Chronic Pain X2 p Value

% % %Education 4.00 0.0032**Less than high school 23.3 47.2 29.5High school 15.1 52.2 32.7Moe than high school 25.2 45.1 29.7Friends 4.25 0.0051**None 27.0 37.4 35.6One to Two 27.5 44.6 28.0Three to Five 21.7 48.3 30.0Six to Ten 17.6 50.2 32.211 to 20 18.1 43.6 38.3More than 20 16.4 45.4 38.2Onset of Disability 12.96 0.0000**Birth to 18 years 24.3 32.2 43.419 to 54 years 30.1 49.0 20.955 to 64 years 21.1 50.8 28.165 to 74 years 19.5 45.4 35.1

75+ years 20.0 38.9 39.2

Severity of Disability 607.62 0.0007**

Mild to moderate 3.3 51.3 45.5Severe to very severe 52.7 36.6 10.6

***p<0.001, **p<0.01, *p<0.05

Bivariate ResultsDescription of Study Population by HRQoL

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

Variables Negative HRQoL Positive HRQoL X2 p Value

% %Sex 0.48 0.4872Female 44.10 55.90Male 42.90 57.10Age 1.37 0.253655 to 64 45.40 54.6065 to 74 42.10 57.9075 + 43.20 56.80Income in Canadian Dollars 12.00 0.0000**

*0 – 22,445 50.50 49.5022,446 – 42,415 46.00 53.0042,416 – 72,040 41.70 58.30≥ 72,041 35.40 64.60Marital Status 7.18 0.0075**Living Alone 46.10 53.90Living With a Partner 41.50 58.50

***p<0.001, **p<0.01, *p<0.05

Variables Negative HRQoL

Positive HRQoL X2 p Value

% %Onset of Disability 1.32 0.07180 to 1 years 29.3 70.71.1 to 5 years 41.2 58.85.1 to 10 years 35.6 64.410.1 to 15 years 48.9 51.115.1 to 20 years 49.7 50.320 plus years 44.5 55.5Severity of DisabilityMild to moderate 28.9 71.1 467.71 0.0000***Severe to very severe 65.9 34.1

***p<0.001, **p<0.01, *p<0.05

Multiple Logistic Regression Model

Predictors of HRQoLStudy Population: Canadian Population with Disability Aged

55+, PALS 2006

Variables AOR 95% CI p Value

SexFemale 0.69** (0.55-0.88) 0.0024Male 1.00 (1.00-1.00) -Age55 to 64 1.00 (1.00-1.00) -65 to 74 0.98 (0.67-1.17) 0.28.3975 + 0.96 (0.64-1.46) 0.4970Income in Canadian Dollars0-22,445 1.68* (1.13-2.25) 0.010822,446-42,415 1.64** (1.20-2.25) 0.001942,416-72,040 1.30 (0.97-1.73) 0.0748≥ 72,041 1.00 (1.00-1.00) -Marital StatusLiving Alone 1.00 (1.00-1.00) -Living With a Partner 1.12 (0.87-1.43) 0.3851

***p<0.001, **p<0.01, *p<0.05

Table (3): Socio-demographic Predictors of Negative HRQoL

Variables AOR 95% CI p Value

FriendsNone 0.97 (0.56-1.67) 0.9087One to Two 1.04 (0.65-1.65) 0.8840Three to Five 0.88 (0.56-1.37) 0.5695Six to Ten 0.94 (0.59-1.50) 0.799211 to 20 0.56* (0.33-0.96) 0.0340More than 20 1.00 (1.00-1.00) -Onset of DisabilityBirth to 18 years 1.00 (1.00-1.00) -19 to 54 years 1.02 (0.61-1.71) 0.935155 to 64 years 1.28 (0.77-2.11) 0.341665 to 74 years 1.25 (0.72-2.17) 0.435875+ years 1.00 (0.51-1.96) 0.9966Severity of DisabilityMild to moderate 1.00 (1.00-1.00) -Severe to very severe 1.51** (1.11-2.06) 0.0097

***p<0.001, **p<0.01, *p<0.05

Variables AOR 95% CI p Value

Agility Yes 1.85*** (1.39-2.47 0.0000No 1.00 (1.00-1.00) -

Communication

Yes 1.19 (0.73-1.93) 0.4861No 1.00 (1.00-1.00) -

Developmental

Yes 1.04 (0.17-6.43) 0.9667No 1.00 (1.00-1.00) -Emotional Yes 1.33 (0.85-2.09) 0.2082No 1.00 (1.00-1.00) -HearingYes 1.03 (0.81-1.32) 0.8042No 1.00 (1.00-1.00) -LearningYes 1.56 (0.95-2.56) 0.0759No 1.00 (1.00-1.00) -

***p<0.001, **p<0.01, *p<0.05

Variables AOR 95% CI p Value

MemoryYes 1.35 (0.83-2.18) 0.2232No 1.00 (1.00-1.00) -MobilityYes 2.26*** (1.91-3.61) 0.0000No 1.00 (1.00-1.00) -SeeingYes 1.37* (1.05-1.80) 0.0209No 1.00 (1.00-1.00) -Unknown DisabilityYes 1.00 (0.41-2.42) 1.0000No 1.00 (1.00-1.00) -Chronic PanMore Severe 3.43*** (2.28-5.15) 0.000Less Severe 1.39* (1.02-1.88) 0.0375No 1.00 (1.00-1.00) -

***p<0.001, **p<0.01, *p<0.05

The oldest old Canadian adults reported less chronic pain than did the youngest old adults (X2=13.51; p=0.0000).

Those affected by chronic pain reported significantly poorer HRQoL compared to those who did not report chronic pain (X2=207.27; p=0.0000).

The age of onset and the type of disability were significantly associated with reported chronic pain.

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: 0.55-0.88); 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: 1.39-2.47); p=0.0000] and [AOR=2.26 (95% CI: 1.91-3.61); p=0.0000 respectively].

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.

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