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 %

Total2,582,50

0100

Age

55 to 64 824,920 31.90

65 to 74 739,500 28.60

75+1,018,09

039.40

Sex

Female1,451,86

059.60

Male1,130,64

040.40

Income in Canadian Dollars

0 – 22,445 550,550 21.30

22,446 - 42,415 738,150 28.60

42,416 – 72,040 673,440 26.10

≥72,041 618,010 24.10

Marital Status

Living Alone 1,167,88

0 45.20

Living With a Partner

1,414,160 54.80

Variables n %

Education

No High School Diploma 533,290 34.80

High School Diploma 245,830 16.00

Higher 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 Disability

Agility 1,871,740 72.50

Communication224,100 8.70

Developmental 26,470 1.00

Emotional 204,770 8.00

Hearing966,420 37.50

Learning212,210 8.20

Memory261,760 10.20

Mobility1,947,000 75.40

Seeing515,270 20.00

Unknown 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 26.6

Male 21.5 41.1 37.5

Age 13.51

0.0000***

55 to 64 28.0 48.2 23.8

65 to 74 21.2 48.4 30.5

75 + 21.0 40.8 38.2

Income in Canadian Dollars

0.61 0.6716

0 - 2245 25.1 44.7 30.2

22446 - 42415 23.3 43.8 32.9

42416 - 72040 23.1 45.6 31.4

≥ 72041 21.9 47.5 30.7

HRQoL207.27

0.0000***

Positive 10.8 47.1 42.1

Negative 38.8 42.3 18.9

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

VariablesSevere

Chronic PainLess Severe Chronic

PainNo Chronic Pain X2 p Value

% % %

Education 4.00 0.0032**

Less than high school 23.3 47.2 29.5

High school 15.1 52.2 32.7

Moe than high school 25.2 45.1 29.7

Friends 4.25 0.0051**

None 27.0 37.4 35.6

One to Two 27.5 44.6 28.0

Three to Five 21.7 48.3 30.0

Six to Ten 17.6 50.2 32.2

11 to 20 18.1 43.6 38.3

More than 20 16.4 45.4 38.2

Onset of Disability 12.96 0.0000**

Birth to 18 years 24.3 32.2 43.4

19 to 54 years 30.1 49.0 20.9

55 to 64 years 21.1 50.8 28.1

65 to 74 years 19.5 45.4 35.1

75+ years 20.0 38.9 39.2

Severity of Disability607.6

20.0007**

Mild to moderate 3.3 51.3 45.5

Severe 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

VariablesNegative HRQoL

Positive HRQoL X2 p Value

% %

Sex 0.48 0.4872

Female 44.10 55.90

Male 42.90 57.10

Age 1.37 0.2536

55 to 64 45.40 54.60

65 to 74 42.10 57.90

75 + 43.20 56.80

Income in Canadian Dollars

12.000.0000**

*

0 – 22,445 50.50 49.50

22,446 – 42,415 46.00 53.00

42,416 – 72,040 41.70 58.30

≥ 72,041 35.40 64.60

Marital Status 7.18 0.0075**

Living Alone 46.10 53.90

Living With a Partner 41.50 58.50

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

VariablesNegative HRQoL

Positive HRQoL

X2 p Value

% %

Onset of Disability 1.32 0.0718

0 to 1 years 29.3 70.7

1.1 to 5 years 41.2 58.8

5.1 to 10 years 35.6 64.4

10.1 to 15 years 48.9 51.1

15.1 to 20 years 49.7 50.3

20 plus years 44.5 55.5

Severity 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

Sex

Female 0.69** (0.55-0.88) 0.0024

Male 1.00 (1.00-1.00) -

Age

55 to 64 1.00 (1.00-1.00) -

65 to 74 0.98 (0.67-1.17) 0.28.39

75 + 0.96 (0.64-1.46) 0.4970

Income in Canadian Dollars

0-22,445 1.68* (1.13-2.25) 0.0108

22,446-42,415 1.64** (1.20-2.25) 0.0019

42,416-72,040 1.30 (0.97-1.73) 0.0748

≥ 72,041 1.00 (1.00-1.00) -

Marital Status

Living 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

Friends

None 0.97 (0.56-1.67) 0.9087

One to Two 1.04 (0.65-1.65) 0.8840

Three to Five 0.88 (0.56-1.37) 0.5695

Six to Ten 0.94 (0.59-1.50) 0.7992

11 to 20 0.56* (0.33-0.96) 0.0340

More than 20 1.00 (1.00-1.00) -

Onset of Disability

Birth to 18 years 1.00 (1.00-1.00) -

19 to 54 years 1.02 (0.61-1.71) 0.9351

55 to 64 years 1.28 (0.77-2.11) 0.3416

65 to 74 years 1.25 (0.72-2.17) 0.4358

75+ years 1.00 (0.51-1.96) 0.9966

Severity of Disability

Mild 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 0.0000

No 1.00 (1.00-1.00) -

Communication

Yes 1.19 (0.73-1.93) 0.4861

No 1.00 (1.00-1.00) -

Developmental

Yes 1.04 (0.17-6.43) 0.9667

No 1.00 (1.00-1.00) -

Emotional

Yes 1.33 (0.85-2.09) 0.2082

No 1.00 (1.00-1.00) -

Hearing

Yes 1.03 (0.81-1.32) 0.8042

No 1.00 (1.00-1.00) -

Learning

Yes 1.56 (0.95-2.56) 0.0759

No 1.00 (1.00-1.00) -

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

Variables AOR 95% CI p Value

Memory

Yes 1.35 (0.83-2.18) 0.2232

No 1.00 (1.00-1.00) -

Mobility

Yes 2.26*** (1.91-3.61) 0.0000

No 1.00 (1.00-1.00) -

Seeing

Yes 1.37* (1.05-1.80) 0.0209

No 1.00 (1.00-1.00) -

Unknown Disability

Yes 1.00 (0.41-2.42) 1.0000

No 1.00 (1.00-1.00) -

Chronic Pan

More Severe 3.43*** (2.28-5.15) 0.000

Less Severe 1.39* (1.02-1.88) 0.0375

No 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.

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), 221- 228.

• 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), 15-24.

• Picavet, H., & Hoeymans, N. (2004). Health related quality of life in multiple musculoskeletal diseases:

SF-36 and EQ-5D in the DMC3 study. Annals of the Rheumatic Diseases, 63(3), 723-729.

• Ramage-Morin, P. L. (2008). Chronic pain in Canadian seniors. Health Reports (Catalogue number 82-003-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.