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Journal of Military, Veteran and Family Health logoLink to Journal of Military, Veteran and Family Health
. 2023 Jun 28;9(3):70–85. doi: 10.3138/jmvfh-2022-0030

Well-being of Veterans with chronic pain with fewer activities limited by pain: Life After Service Survey 2019

Goris Nazari a, Julián Reyes-Vélez b, James M Thompson c, Jill Sweet b, Jordan Miller a
PMCID: PMC13293149  PMID: 42533943

Abstract

Introduction :

There is considerable variance in the relationship between pain severity and activities limited by pain in Canadian Armed Forces (CAF) Veterans. It is possible those who reported fewer activities with pain may be doing better in certain well-being domains. Understanding these relationships may guide future research and clinical care. This article reports the prevalence of chronic pain in CAF Veterans, describes their characteristics, and identifies well-being indicators associated with fewer activities limited by pain.

Methods :

The Life After Service Survey (LASS) 2019 survey was a Statistics Canada cross-sectional, computer-assisted telephone interview survey of the well-being of CAF Regular Force Veterans released in 1998–2018. Data were analyzed using descriptive analysis and ordinal logistic regression modelling.

Results :

There were 1,222 Veterans who reported living with chronic pain, with a prevalence of 50.7% (95% CI, 48.0–53.4). Those with moderate or severe pain who reported no or few activities limited by pain were more likely to be ages 50–59 years, female, and employed, and more likely to have higher education, higher rank, longer length of service, or higher income adequacy. They were also more likely to be satisfied with family, main activities, or finances. Regression modelling in those with moderate to severe pain demonstrated those with fewer activities limited by pain were less likely to have low mastery (unadjusted odds ratio = 18.5; 95% CI, 8.0–42.6).

Discussion :

The strong association between a sense of mastery and fewer activities limited by pain provides important avenues for future research.

Key words: activities limited by pain, Canadian Armed Forces, CAF, chronic pain, mastery, military, pain limitations, Veterans, well-being

Lay Summary

This study aimed to understand how common chronic pain is among Canadian Armed Forces (CAF) Veterans and the characteristics that were related with having fewer activities limited by pain using the Life After Service Survey (LASS) 2019. The LASS was a Statistics Canada telephone survey of CAF Veterans released in 1998–2018. About 1 in 2 (50.7%) reported living with chronic pain. CAF Veterans between 50 and 59 years who were female, employed, had higher education, higher rank, longer length of service, or higher income had fewer activities limited by chronic pain. High levels of mastery (feeling in control of factors affecting one’s life) was linked to having fewer activities limited by pain among people with moderate to severe pain. The strong link between higher mastery and fewer activities limited by pain points to a need for pain management supports addressing aspects of CAF Veterans’ well-being beyond pain severity and physical health.

Introduction

Chronic pain occurs in nearly 20% of the general population.1,2 The Life After Service Survey (LASS) surveys of Canadian Armed Forces (CAF) Regular Force Veterans released since 1998 reported significantly higher prevalence of chronic pain in military Veterans compared with the Canadian general population, with an estimated 41% to 64% of military Veterans reporting chronic pain.3,4 Chronic pain in CAF Veterans has been associated with multiple aspects of military service, including training, military occupations, deployment, and combat.3,5–9 Painful conditions are a common reason for early release from service in Canada and internationally.4,9

Studies have indicated CAF Veterans have a higher prevalence of chronic physical and mental health conditions than the Canadian general population.4,10,11 In addition, data from the LASS 2016 survey indicated CAF Veterans released from 1998 had considerable heterogeneity in physical and mental health conditions, psychological comorbidity, degrees of functional impairment, and well-being in various aspects of life.12

The transition from military service to civilian life can be difficult, especially for Veterans living with chronic health conditions such as chronic pain.13–16 Management of chronic pain can be challenging, requiring interprofessional approaches that aim to address several domains identified in the Veterans Affairs Canada (VAC) well-being framework: health, employment, or other meaningful activity, finances, life skills/preparedness, social integration, housing/physical environment, and cultural/social environment.16 The domains of well-being framework emphasizes the need to find solutions for Veteran-centric supports that target multiple aspects of functioning and well-being.

The relationship between pain severity and functioning is complex. Previous research demonstrated higher pain intensity is associated with reduced functioning.11 However, the relationship between pain intensity and functioning is not significant when pain interference (how someone perceives pain to influence their life) is included as a mediator.11 Additionally, while pain interference and physical functioning are moderately associated when measured concurrently, they are not closely associated when measured over time.11 This research suggests pain interference should be considered a distinct construct and potentially a distinct target for pain management.11 This evidence also identifies a need to better understand the factors that are related to pain interference so tailored pain management strategies can be developed to address these factors rather than simply addressing pain intensity or physical functioning.

Evidence from previous research demonstrated substantial variation in the relationship between pain severity and pain interference (self-reported activities limited by pain) in CAF Veterans. For example, a cluster analysis using 2016 LASS data indicated that one cluster of Veterans, in which 88.7% reported moderate to severe pain intensity, only 18.3% reported no or few activities limited by pain.17 Furthermore, in another cluster of Veterans where 65.7% reported moderate to severe pain, 42.1% reported some or most activities were limited by pain.17 One potential explanation for the variance in activities limited by pain reported by Veterans not explained by pain intensity alone is that those who reported fewer activities limited by pain may be doing better in certain well-being domains.

The LASS 2019 survey data provided an opportunity to make more recent prevalence estimates of chronic pain and to explore the relationship between the domains of the VAC well-being framework and activities limited by pain. Therefore, the objectives of using the most recent LASS cross-sectional dataset (2019) were to 1) report the most recent estimate of the prevalence of chronic pain in CAF Veterans, 2) describe the characteristics of Veterans with and without chronic pain, 3) describe the characteristics of Veterans living with chronic pain who reported few versus more activities limited by pain, and 4) identify well-being indicators associated with fewer activities limited by pain in CAF Veterans with moderate to severe chronic pain.

Methods

Study design and population

The LASS 2019 survey was a Statistics Canada cross-sectional, computer-assisted telephone interview survey of the well-being of male and female CAF Regular Force Veterans released in 1998 to 2018 (n = 3,671) and surveyed between March and May 2019.18 The response rate was 72% (n = 2,630), and 92% (n = 2,411) of them consented to share their data. Study participants, at the time of the survey, had not re-enrolled in the CAF and were not living in institutions, the Canadian territories (Northwest Territories, Nunavut, and Yukon) or outside Canada. The geographical location exclusion was related to the difficulty in contacting people. Entry ranks were excluded because previous studies showed they were more like the general population than Veterans. The survey excluded Veterans released at entry ranks of second lieutenant, acting sub-lieutenant, and private recruit. The survey was stratified by rank at release and included questions from national Canadian population health studies, including the Canadian Community Health Survey (CCHS), to cover multiple domains of well-being.4 Veteran status and military characteristics were obtained by Statistics Canada from the Department of National Defence human resources database. Other indicators were self-reported.

Data collection for the LASS 2019 survey was funded by VAC and carried out by Statistics Canada using computer-assisted telephone interviews. This study used anonymous data from respondents who consented to share data with VAC. Policy committees at Statistics Canada that serve as a research ethics board reviewed and provided approval to access and analyze the survey study data. Ethical approval for this analysis was obtained from the Queen’s University Health Sciences and Affiliated Teaching Hospitals Research Ethics Board in Kingston, Canada (file # 6032346).

Variables

Sociodemographic and military characteristics

Age, military characteristics including rank at discharge (officer, senior non-commissioned member, junior non-commissioned member), service element (army, navy, air force), and years of service (< 10 years, 10–19 years, ≥ 20 years) were obtained by Statistics Canada from the Department of National Defence human resources database. Questions from the CCHS were used for sex, relationship status, education attained, and marital status.

Pain intensity and activities prevented by pain

Self-reported chronic pain was assessed using the pain module in the Health Utilities Index Mark 3 (HUI-3).18 The HUI-3 chronic pain module question to identify chronic pain was “Are you usually free of pain or discomfort (yes/no).”18 For those that answered no, pain intensity was assessed with the question “How would you describe the usual intensity of your pain or discomfort? (mild, moderate, severe),”18 and the number of activities prevented by pain was assessed with the question “How many activities does your pain or discomfort prevent? (none, a few, some, or most).”18 The utility of the HUI-3 chronic pain module was evaluated for the general Canadian population and was previously used in general population surveys.19

Well-being indicators

Well-being in this article refers to the conceptual framework used at VAC in which well-being is assessed across seven subordinate domains: health, employment or other meaningful activity, finances, life skills/preparedness, social integration, housing/physical environment, and cultural/social environment. In this framework, well-being fluctuates across the life course in any domain in response to interconnected determinants from all the domains.10

Health

Well-being indicators captured under the health domain included self-rated physical health (presence and number of chronic physical health conditions) and self-rated mental health (presence of chronic mental health conditions, presence of suicidal ideations, and perceived life stress).

Self-rated physical health

Presence and number of physical health conditions were determined using the chronic physical health conditions questions from the CCHS.18 Following the preamble, “We are interested in conditions diagnosed by a health professional and are expected to last or have already lasted 6 months or more,” survey participants were asked about the presence of several sentinel chronic conditions. Physical health condition questions were grouped by organ system: musculoskeletal (arthritis or low back pain), obesity, central nervous system (dementia, effects of traumatic brain injury, migraine), cardiovascular (hypertension, effects of stroke), gastrointestinal (Crohn’s disease, ulcerative colitis, irritable bowel syndrome, or bowel incontinence), respiratory (asthma, chronic bronchitis, emphysema, or chronic obstructive pulmonary disease), urinary incontinence, and diabetes. Hearing problems were assessed with the HUI-3 hearing module as in prior LASS analyses.20 Two variables were created: presence of at least one physical health condition and number of physical health conditions.

Self-rated mental health

Presence of a mental health problem was assessed using a composite measure of mental health problems derived from the Kessler Psychological Distress Scale (K-10) and Primary Care Posttraumatic Stress Disorder (PC-PTSD) symptom measures, along with the absence/presence of self-reported diagnosed chronic mental health conditions (including mood disorders, anxiety disorders, or PTSD), in three levels of mental health problem severity: no/little, moderate, and severe.21

The chronic diagnosed mental health condition questions were as follows: 1) “Do you have a mood disorder such as depression, mania, dysthymia or bipolar disorder?” 2) “Do you have an anxiety disorder such as a phobia, obsessive-compulsive disorder or a panic disorder?” and 3) “Do you have posttraumatic stress disorder (PTSD)?” Past-month psychological distress symptoms of depression and anxiety were assessed with the K-10 with scores ranging from 0 to 40 based on Canadian and Australian studies of general and military populations. Cut-offs were 0–9 for no/little distress, 10–19 for mild/moderate, and 20–40 for severe.21,22

PTSD symptoms were assessed using the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) version of the PC-PTSD screener to examine for possible PTSD in three categories: none, 1 or 2 of 4 criteria, or 3 or 4 of 4 criteria. Based on a validation study of U.S. Veterans Health Administration patients, a cut-off threshold of 3 criteria was used to detect possible PTSD.23,24 The authors included 1–2 PC-PTSD criteria owing to the importance of subthreshold PTSD.21 These measures were combined into a composite mental health problem variable developed for LASS analyses.20 First, respondents with either K-10 scores of 20–40 or 3–4 PC-PTSD criteria were assigned to the severe mental health problem category, regardless of whether they reported having a diagnosed mental health condition. Those with no diagnosed mental health condition, a K-10 score of 0–9, and no PC-PTSD criteria were assigned to the no/little category. All others were categorized as mild/moderate.

Presence of suicidal ideation in the past year was examined with the question “Have you ever seriously considered committing suicide or taking your own life?” followed by “Has this happened in the past 12 months?”

Perceived life stress was assessed with a three-category indicator of activity limitations based on previous LASS analyses that used two questions from the CCHS: 1) no activity limitations, 2) health-related activity limitations (HRAL), whether a long-term physical or mental condition or health problem reduced the amount or kind of activity at home, school, work, or other, sometimes or often, and 3) need for assistance with at least one basic or instrumental activity of daily living (ADL assistance need).25

Employment or other meaningful activity

The following CCHS question was used to capture participants’ main activity: “Now we would like you to think about the past 12 months. What has been your main activity in the past 12 months?” Main activity variables included working or service in the reserves, retired/not looking for work, looking for work/school/caregiving, and disabled or on disability insurance. The following question was used to assess satisfaction with main activity: “Thinking about this (main) activity in the past 12 months, how satisfied are you?” Satisfaction variables had five response categories, reduced to three: satisfied/very satisfied, neither, and dissatisfied/very dissatisfied.

Finances

Income adequacy was measured by adjusting household income for number of people in the household using the ratio of household income to Statistics Canada’s 2018 low-income measure. Quintiles were established using weighted data in an automated SPSS procedure.26 Satisfaction with finances was measured using the following question: “How satisfied are you with your financial situation?” There were five response options, reduced to three categories in this analysis: satisfied/very satisfied, neither, and dissatisfied/very dissatisfied.26

Life skills/preparedness

Mastery is an individual’s perceived control over important life events. Mastery was assessed using a 7-item scale used in prior analyses of LASS and CAF data.27,28 The scale’s scores range from 0 to 28. The variable was categorized using cut-offs established for prior studies, with 7 or less indicating low mastery and 23 or more indicating high mastery.28 Scores between 7 and 23 were considered medium mastery.

Social integration

Satisfaction with family relationship was assessed with the question “How satisfied are you with your relationships with family members?” There were five response options, reduced to three categories in this analysis: satisfied/very satisfied, neither, and dissatisfied/very dissatisfied.29 Perceived social support was assessed with the 10-item Social Provisions Scale with scores up to 40. As in prior LASS analyses, low perceived social support was indicated with a score of less than 30.29

Group identity was derived by combining two questions.30 First, “How would you describe your sense of belonging to your local community?” with four response options combined into two categories: very/somewhat strong and very/somewhat weak. Second, one of the 10 items in the SPS-10 Social Provisions Scale: “I feel part of a group of people who share my attitudes and beliefs.”30 Responses were grouped into two categories: agree/strongly agree and disagree/strongly disagree. The two measures were combined into a measure with two categories: strong (very/somewhat strong sense of local community belonging and agree/strongly agree that they feel part of a group with shared attitudes and beliefs) and weak (the other three combinations of these two variables).30

Health care use

Health care use was assessed using questions about the number of past-year visits to physicians. Responses were categorized in three categories: low (< 5), medium (5–9), and high (10 or more).

Statistical analysis

To report the prevalence of chronic pain, describe the characteristics of Veterans with and without chronic pain, and describe the characteristics of those who reported few/more activities limited by pain (objectives 1 to 3), descriptive analyses were performed using weighted estimation for the prevalence of chronic pain and the distribution of each variable. Unweighted frequencies were transformed to weighted data to represent the Canadian Veteran population through weights provided by Statistics Canada to account for the survey’s stratified design. Differences between those with and without pain, and differences across degrees of pain interference/pain severity, were assessed using a Pearson Chi-squared test. Statistical significance was determined if p < 0.05. This initial descriptive assessment was performed in SPSS (IBM Corp., Armonk, NY, USA) version 25 for Windows.

To identify well-being indicators associated with fewer activities limited by pain in CAF Veterans with moderate to severe chronic pain (objective 4), ordinal logistical regression using weighted data was used to assess the relationships between a parsimonious set of independent variables and the dependent variable number of activities limited by pain. The analyses were carried out using Stata, version 15.1 (StataCorp LLC, College Station, TX). Adjusted modelling was conducted in a forwards selection using three blocks of independent variables: first, socio-economic status, second, adding satisfaction, social support, mastery, and group identity (variables describing what matters to the Veteran), and third, adding health status. Non-significant independent variables were removed at each step. The independent variables were chosen by considering prior findings of associations between the independent variables and chronic pain and by theorized relationships of well-being factors to pain interference based on the literature and clinical experience.5,8,17,31,32 Correlations between all pairs of the variables were examined to rule out significant collinearity. A proportional odds model was selected to explore the relationship of the independent variables and the log odds of the ordinal levels of the number of activities limited by pain. The proportional assumption was assessed for each of the independent variables, removing those variables not meeting the Brant test assumption of proportionality.33,34

Results

Prevalence of chronic pain severity

There were 1,222 Veterans who reported living with chronic pain or discomfort, for a weighted prevalence of 50.7% (95% CI, 48.0–53.4). The weighted prevalence of chronic pain or discomfort was 50.1% (95% CI, 47.2–53.0) in men and 54.0% (95% CI, 46.1–61.7) in women. Mild pain intensity was reported by 21.9%, moderate pain intensity was reported by 61.2%, and severe pain intensity was reported by 16.9%.

Characteristics of Veterans with and without chronic pain

Table 1 compares Veterans with and without chronic pain based on socio-economic, military, health status, and health care use characteristics. The frequency distributions within all variables were statistically significant. Veterans with pain were slightly older (mean 50.7 years) than those without pain (mean 49.3 years) and were slightly more often female. Those with chronic pain more often had lower education, reported disabilities or being on disability benefits as a main activity, had lower income, were non-commissioned members, served in the army, had longer years of service, and had poorer physical or mental health status measured several ways. All physical conditions reported were more prevalent in those with pain, and 95% of Veterans with chronic pain had at least one of the physical conditions asked about in the survey. Almost three-quarters (71%) of those with pain had a mental health problem, and 68% had both a physical health condition and mental health problem, compared with 27% of those without chronic pain. Health-related activity limitations were more prevalent (49% vs. 29%), and a higher proportion reported needing assistance with ADL (43% vs. 6%), in respondents with chronic pain. High health care use (10 or more physician visits in the past year) was 4 times as prevalent in those with pain as without (20% vs. 5%).

Table 1.

Socioeconomic, military, and health status and health care use characteristics of Veterans with and without chronic pain (weighted data, LASS 2019)

Variable Category Weighted percent
With pain No pain Total
Age* < 40 18.9 26.8 22.8
40–49 20.3 18.7 19.5
50–59 40.2 30.8 35.6
60+ 20.6 23.6 22.1
Sex* Male 86.6 88.3 87.4
Female 13.4 11.7 12.6
Relationship status* Married/common law 77.7 79.0 78.4
Separated/widowed/divorced 12.6 9.8 11.2
Single/never married 9.7 11.2 10.4
Education* High school or less 45.1 38.0 41.6
Post-secondary < bachelor 40.6 40.1 40.4
Post-secondary ≥ bachelor 14.3 21.8 18.0
Main activity* Working or reserves 48.0 71.6 59.7
Retired, not looking for work 23.3 19.3 21.3
Looking for work/school/caregiving 8.2 6.5 7.4
Disability or on disability 20.5 2.5 11.6
Income adequacy* Low 1 24.9 19.2 22.1
2 18.7 20.3 19.5
3 20.2 17.6 18.9
4 19.8 20.6 20.2
High 5 16.4 22.2 19.3
Rank at release* Officer 13.1 21.9 17.5
Senior NCM 34.0 26.2 30.1
Junior NCM 52.9 51.8 52.4
Service element* Army 56.1 46.5 51.4
Navy 14.0 18.6 16.2
Air Force 29.9 35.0 32.4
Length of service* < 10 years 19.3 34.5 27.2
10–19 years 23.7 13.2 18.5
≥ 20 years 57.0 51.4 54.3
Health status* SRH excellent/very good* 18.3 60.8 39.2
SRMH excellent/very good* 32.4 64.7 48.3
Any physical health condition* 95.5 65.8 80.9
Any mental health problem (MHP* 71.0 35.7 53.4
2+ physical health conditions* 76.9 35.2 56.4
PHC + MHP* 68.1 27.2 47.9
Quite a bit/extreme life stress* 34.5 17.2 26.0
Suicidal ideation—past 12 months** 15.8 3.7 9.8
Chronic physical conditions* Musculoskeletal* 84.8 28.0 56.8
Obesity* 40.3 27.7 34.1
Cardiovascular* 32.0 23.1 27.6
Central nervous system* 34.1 9.6 22.0
Hearing problem* 23.4 10.2 16.7
Gastrointestinal* 19.5 5.4 12.6
Respiratory* 13.3 6.6 10.0
Diabetes* 10.1 6.9 8.5
Urinary* 6.7 2.2 4.5
Activity limitations* None 8.1 64.4 35.8
HRAL 49.0 29.3 39.3
ADL assistance need 42.9 6.3 24.9
Past-year physician visits* Low 0–4 55.5 80.4 67.8
Medium 5–9 24.7 14.8 19.8
High 10+ 19.7 4.8 12.3
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*

Difference between those with and without pain statistically significant, p < 0.000, Pearson Chi-squared test.

NCM = non-commissioned member; SRH = self-rated health; SRMH = self-rated mental health; PHC = physical health condition; MHP = mental health problem; HRAL = health-related activity limitation; ADL = activities of daily living.

Characteristics of Veterans with fewer activities limited by pain versus those with more activities limited by pain, given similar pain severity

Figure 1 shows the relative proportions of Veterans with chronic pain or discomfort by number of activities prevented by pain, stratified by pain severity. One-fifth (20.3%) had moderate to severe pain but no or few activities limited by pain. Conversely, 5.3% had mild pain but some or most activities limited by pain.

Figure 1.

Figure 1.

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Percent of Veterans with chronic pain or discomfort by number of activities prevented by pain and pain severity

The characteristics of Veterans with four combinations of activities limited by pain and pain severity are presented in Table 2. Three-quarters (78%) had moderate or severe chronic pain. Among those with moderate or severe pain, the group with no or few activities limited by pain was more often ages 50–59 years, female, or employed, or had higher education, higher rank, longer length of service, or higher income adequacy. They were more often satisfied with their family, main activity, and finances.

Table 2.

Socioeconomic, military, satisfaction, social, health, and health care use characteristics of the four combinations of pain interference with activity and pain severity

Variable Pain interference with activity/pain severity (weighted percent of those with chronic pain for each variable within each column)
None or few activities/mild pain (16.7%) None or few activities/ moderate-severe pain (20.3%) Some or most activities/mild pain (5.3%) Some or most activities/moderate-severe pain (57.7%) Total (100%)
Age*
 30–39 26.8 15.4 11.6 18.6 19.0
 40–49 21.2 20.2 15.6 20.6 20.4
 50–59 29.3 38.0 52.3 42.9 40.1
 60+ 22.6 26.4 20.5 17.9 20.6
Sex*
 Male 90.1 83.2 83.3 87.0 86.6
 Female 9.9 16.8 16.7 13.0 13.4
Relationship status*
 Married, common law 78.8 72.1 76.2 79.6 77.8
  Widowed/separated/divorced 11.0 12.7 15.5 12.8 12.6
 Single, never married 10.2 15.2 8.3 7.6 9.6
Satisfaction with family*
 Satisfied or very satisfied 83.7 87.0 76.2 68.5 75.2
 Neither 9.9 9.0 9.1 16.5 13.5
 Dissatisfied/very dissatisfied 6.4 4.0 14.8 15.0 11.3
Education level attained*
 High school or less 36.5 44.1 34.2 49.0 43.1
 Post-secondary not degree 44.4 36.1 35.7 41.7 40.7
 University degree 19.1 19.8 30.1 9.4 14.2
Main activity*
 Employed or reserves 71.2 57.7 44.2 38.4 47.7
 Retired, not looking 19.1 27.6 35.0 3.8 23.2
 On disability 2.1 7.8 14.8 30.7 20.5
 Other 7.5 6.9 6.0 9.1 8.3
Satisfaction with main activity*
 Satisfied/very satisfied 73.3 71.8 66.8 50.2 60.1
 Neither 15.4 17.1 8.4 17.2 16.4
 Dissatisfied/very dissatisfied 7.3 11.1 24.8 32.6 23.6
Income adequacy*
 Low 1 17.2 25.8 21.2 27.2 24.9
 2 17.5 14.9 21.9 20.1 18.7
 3 13.9 22.0 18.9 21.6 20.3
 4 32.7 17.2 13.7 17.3 19.7
 High 5 18.6 20.1 24.3 13.8 16.4
Satisfaction with finances*
 Satisfied/very satisfied 68.1 74.4 71.0 59.9 64.8
 Neither 21.8 12.3 16.5 18.3 17.6
 Unsatisfied/very unsatisfied 10.0 13.3 12.5 21.8 17.6
Last military rank*
 Officer  20.9  15.1  22.8  9.1  13.0
 Senior NCM  23.3  40.3  38.7  34.4  34.0
 Junior NCM  55.7  44.6  38.5  56.5  53.0
Length of service*
 < 10 years 29.5 16.8 3.4 18.8 19.3
 10–19 years 18.6 16.7 27.1 27.2 23.7
 20+ years 51.8 66.6 69.4 54.0 57.0
Social support*
 High 88.7 77.1 87.1 62.4 71.2
 Low (score ≤ 29) 11.3 22.9 12.9 37.6 28.8
Mastery*
 High 23.0 21.7 9.6 9.6 16.2
 Medium 75.2 77.3 79.4 79.4 76.6
 Low 2.1 1.8 1.0 11.1 7.1
Group identity*
 Strong SOCB, in group 54.2 48.8 53.0 28.2 38.0
 Strong SOCB, not in group 1.7 4.9 4.5 3.8 3.7
 Weak SOCB, in group 34.6 29.1 29.1 37.9 35.1
 Strong SOCB, not in group 9.5 17.3 13.3 30.2 23.2
Perceived health*
 Excellent/very good 44.3 23.0 17.6 9.3 18.3
 Good 42.6 48.1 39.1 26.0 34.0
 Fair/poor 13.2 28.8 43.3 64.7 47.7
Perceived mental health*
 Excellent/very good 55.5 44.7 29.5 21.8 32.5
 Good 25.7 25.5 27.2 22.6 23.9
 Fair/poor 18.8 29.8 43.3 55.6 43.6
Number of chronic physical health conditions*
 0 11.8 6.1 2.4, 2.1 4.5
 1 29.5 20.4 23.7 14.4 18.6
 2 27.3 30.6 28.0 23.9 26.1
 3 or more 31.4 42.9 46.0 59.6 50.8
Mental health problem*
 No/little 45.4 44.1 32.8 18.8 29.0
 Mild/moderate 35.6 30.8 31.3 28.6 30.3
 Severe 19.0 25.1 35.8 52.6 40.6
Chronic physical health conditions (Reference = not present)*
 Musculoskeletal 71.8 82.6 89.1 89.0 84.8
 Obesity 34.1 37.3 43.6 43.0 40.4
 Central nervous system 20.5 26.1 19.5 42.3 34.2
 Cardiovascular 27.8 35.8 27.9 32.2 32.0
 Hearing problem 2.7 15.1 29.9 32.0 23.4
 Gastrointestinal 11.8 21.2 10.7 22.1 19.6
 Respiratory 10.1 6.8 6.9 17.2 13.4
 Diabetes 7.6 7.9 15.0 11.0 10.0
 Urinary 2.1 3.3 4.4 9.4 6.7
Activity limitations*
 None 29.5 8.8 4.2 2.0 8.1
 HRAL, no ADL need 60.0 66.7 53.9 39.2 49.0
 ADL need 10.5 24.5 41.9 58.8 42.9
Past-year physician visits*
 Low 0–4 72.6 62.1 53.5 48.4 55.5
 Medium 5–9 16.8 22.4 33.5 27.0 24.7
 High 10+ 10.8 15.5 13.0 24.6 19.8
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*

Differences across degrees of pain interference/pain severity statistically significant, p < 0.000, Pearson Chi-squared test.

Other main activities = Looking for work, in school or training, or caregiving.

SOCB = sense of community belonging; HRAL = health-related activity limitations; ADL = activities of daily living.

Well-being indicators associated with fewer activities limited by pain

Results of regression modelling to assess associations of well-being factors with increasing number of activities limited by pain is presented in Table 3. The unadjusted odds ratios (UOR) suggested age — but not sex — was significantly associated with an increasing number of activities limited by pain. Therefore, age, but not sex, was used in the adjusted regression analyses. The UORs indicated weak associations with low education (UOR 1.9–2.0), low-income adequacy (UOR 1.5–2.0), and dissatisfaction with finances (UOR 1.8–2.0). There were moderate associations with weak group identity (UOR 2.7), dissatisfaction with main activity (UOR 3.5), and family (UOR 3.7), and low social support (UOR 2.3). Associations were strongest for severe mental health problem (UOR 4.3), three or more chronic physical health conditions (UOR 4.5), and low sense of mastery (UOR 18.5).

Table 3.

Ordinal logistic regression findings for number of activities limited by pain, in those with moderate to severe pain (n = 968)

Number of activities limited by pain
(weighted percent of those with chronic pain for each variable within each column)
Adjusted odds ratio
Variable None (9.6%) A Few (27.4%) Some (31.7%) Most (31.3%) Total (100%) Unadjusted odds ratio Model 1 Model 2 Model 3 95% CIs
Ages
 30–39 24.5 14.0 19.6 17.7 17.8 Ref. Ref. Ref. Ref.
 40–49 9.4 21.9 19.7 21.4 20.5 1.0 1.1 0.9 0.9 0.5–1.6
 50–59 30.1 39.2 39.3 46.2 41.6 1.1 1.2 1.4 1.3 0.7–2.1
 60+ 36.0 24.9 21.4 14.7 20.1 0.6 0.6 0.7 0.7 0.4–1.2
Sex
 Male 94.4 81.4 88.1 86.1 86.0 Ref. Ref. Not used Not used
 Female 5.6 18.6 11.9 13.9 14.0 1.1 0.9 — —
Relationship status
 Married, common-law 79.5 71.0 85.2 74.5 77.7 Ref. Ref. Not used Not used
 Widowed/separated/divorced 12.9 12.6 8.6 16.6 12.7 1.4 1.1 — —
 Single, never married 7.7 16.4 6.2 8.9 9.6 0.7 0.5 — —
Education level attained
 High school or less 53.9 42.5 46.4 51.3 47.7 2.0*** 1.5 Not used Not used
 Post-secondary not degree 34.9 36.3 43.2 40.4 40.2 1.9** 1.4 — —
 University degree 11.1 21.2 10.5 8.3 12.1 Ref. Ref. — —
Income adequacy
 Low 1 33.2 26.6 22.2 38.7 30.0 2.0** 2.0** 1.4 Not used
 2 20.3 19.0 21.2 19.7 20.1 1.9* 1.7* 1.1 —
 3 8.7 23.7 26.0 20.1 22.6 1.5** 1.4 1.2 —
 4 28.1 19.2 18.6 13.1 16.9 1.2 1.1 1.1 —
 High 5 9.7 11.4 12.0 8.4 10.4 Ref. Ref. Ref. —
Satisfaction with main activity
 Satisfied/very satisfied 70.0 72.1 59.0 42.3 55.9 Ref. Not used Ref. Ref.
 Neither 14.7 17.4 17.3 17.0 17.1 1.5** — 1.0 0.9 0.6–1.4
 Dissatisfied/very Dissatisfied 15.3 10.5 23.7 40.7 26.9 3.5*** — 1.9 1.4 0.9–2.2
Satisfaction with finances
 Satisfied/very satisfied 63.8 76.0 65.6 54.7 63.7 Ref. Not used Ref. Not used
 Neither 17.6 11.5 16.1 20.4 16.8 1.8** — 1.1 —
 Unsatisfied/very unsatisfied 18.6 12.4 18.3 24.9 19.5 2.0** — 0.6 —
Satisfaction with family
 Satisfied or very satisfied 92.5 86.1 75.9 61.8 73.3 Ref. Not used Ref. Ref.
 Neither 6.6 9.4 14.5 18.3 14.5 2.1** — 1.5 1.4 0.8–2.5
 Dissatisfied/very dissatisfied 0.9 4.4 9.6 20.0 12.2 3.7*** — 2.3* 2.0* 1.0–3.9
Social support
 High 14.9 24.2 28.4 46.3 33.7 Ref. Not used Ref. Not used
 Low (score ≤ 29) 85.1 75.8 71.6 53.7 66.3 2.3*** — 1.1 —
Mastery
 High 39.6 20.3 13.2 6.2 13.1 Ref. Not used Ref. Ref.
 Medium 60.4 77.6 83.3 75.8 78.3 2.7*** — 1.7* 1.8** 1.0–3.2
 Low 0.0 2.1 3.5 18.0 8.6 18.5*** — 7.0*** 6.6*** 2.4–17.9
Group identity
 Strong 47.8 48.9 38.7 18.7 33.5 Ref. Not used Ref. Ref.
 Not strong 52.2 51.1 61.3 81.3 66.5 2.7*** — 1.5** 1.4* 1.0–1.9
Number of chronic physical health conditions
 0 10.8 5.4 3.1 1.2 3.1 Ref. Not used Not used Ref.
 1 19.1 20.6 17.7 11.3 15.9 2.2 — — 2.5* 1.0–6.3
 2 26.8 31.3 26.3 21.7 25.7 2.5*** — — 2.1* 0.8–5.4
 3 or more 43.3 42.8 52.9 65.8 55.3 4.5*** — — 3.4*** 1.4–8.1
Mental health problem
 No/little 53.5 42.6 25.0 13.3 25.3 Ref. Not used Not used Ref.
 Mild/moderate 26.5 31.5 30.2 27.1 29.1 2.2*** — — 1.7** 1.0–2.5
 Severe 20.1 25.9 44.8 59.6 45.6 4.3*** — — 2.1*** 1.3–3.3
Open in a new tab

Other main activities = Looking for work, in school or training, or caregiving.

SOCB = Sense of community belonging.

95% CIs = 95% confidence intervals.

*

p < 0.05

**

p < 0.01

***

p < 0.001 significantly different from odds ratio of 1.0.

The weak association with income adequacy persisted in Adjusted Model 1 (sociodemographic and military characteristics) but was not significant in Adjusted Model 2, when satisfaction, social support, mastery, and group identity were added. In Model 2, the mastery association remained strong (adjusted odds ratio [AOR] = 7.0) and the association persisted for dissatisfaction with family (AOR = 2.3) and weak group identity (AOR = 1.5). When health status was added in Model 3, the associations with mastery remained strong (AOR = 6.6), and the association with dissatisfaction with family (AOR = 2.0) and weak group identity (AOR = 1.4) remained significant. There was also an association with mental health problems (AOR = 1.7–2.1) and number of chronic physical health conditions (AOR = 2.5–4.4).

Discussion

In LASS 2019, half (51%) of CAF Regular Force Veteran respondents reported chronic pain, 22% mild and 78% moderate to severe. Chronic pain prevalence was higher in those older or female. Chronic pain prevalence was higher in those with activity limitations, lower education, or lower income. Veterans with moderate to severe pain who reported fewer activities limited by pain also more often reported higher scores in the well-being domains. Mastery stood out as the characteristic most strongly associated with having fewer activities limited by pain among those with moderate to severe pain.

This study adds to existing evidence that the determinants and sequelae of chronic pain are complex and multifaceted, including socio-economic, psychological, and physical health factors.35 Chronic pain often has multiple contributing factors. Therefore, gaining insights into its associated factors can facilitate the identification of specific prevention and management strategies to enhance supports for those affected.36 In this study, chronic pain among Veterans was more prevalent in those older and female, and those who reported activity limitations, lower education, and lower income than those without chronic pain. Veterans with chronic pain were more likely to be non-commissioned members, with army experience, longer years of service, or poorer physical or mental health status. Similar socio-demographic risk factors such as age,37,38 sex,39 disability,36 and lower education and income40 have been reported for chronic pain in general populations. In addition, comorbidity of physical and mental conditions has also been associated with chronic pain.41,42

This analysis found a strong association between mastery and the number of activities limited by pain. Mastery had the highest unadjusted odds ratios in all the adjusted models, independent of the presence of physical health conditions and mental health problems. Mastery is viewed as the degree to which people consider themselves as being in control of factors that impact their lives.43 Mastery is considered one of the modifiable personal characteristics that can lower the adverse effects of stress by reducing feeling of vulnerability when encountering threatening events.43 Mastery is reported to be associated with adaptive coping styles when attempting to deal with stressors.44 Furthermore, Stephens et al.45 indicated the attainment of higher levels of mastery was associated with potentially modifiable factors such as higher education, stronger social support, and lower day-to-day life stresses in several areas of life. The association between mastery or locus of control and pain interference was also demonstrated in the civilian literature.46 Greater sense of mastery has been associated with greater life satisfaction and less depression.45 Furthermore, mastery is associated with resiliency when dealing with stressful incidents in life47 and, therefore, can be considered as a valuable, modifiable personal characteristic that may promote better physical, mental, and social health, and overall better well-being among CAF Veterans. This research indicates mastery may be an important modifiable factor that could be targeted to support reductions in perceived pain interference.

There was a strong association between the number of physical health conditions and greater severity of mental health problems and activities limited by pain in this study. These findings are both consistent with previous literature suggesting a greater number of chronic conditions is associated with chronic pain, activity limitations, and reduced quality of life,48–51 and that chronic pain is associated with both physical and mental health conditions.8 These findings emphasize the need for multimodal and interprofessional pain management approaches addressing an array of well-being factors beyond just mental and physical health aspects of the pain experience for Veterans living with chronic pain.

Strengths and limitations

Strengths of this study include external determination of Veteran status and military characteristics using data linkage as opposed to relying on self-report. The sample size is statistically representative of CAF Regular Force Veterans who were released in 1998–2018. The weighting process used by Statistics Canada adjusted for sampling stratification and non-response. Statistics Canada conducted this survey independent of VAC and the CAF.

Limitations included the cross-sectional nature of the data; statistical associations can be demonstrated but causality cannot be concluded. The study findings are male-centric since the LASS dataset contained relatively few women because of a lower proportion of women in military service. The HUI-3 pain measure has not been fully validated for use in Veterans. The survey covered many well-being domains but might not have assessed other relevant factors associated with fewer activities limited by pain. Furthermore, activity intensity may moderate the relationship with pain. It is possible that Regular Force Veterans released since 1998 may differ from Veterans released in prior eras. In the LASS 2019 survey, Reserve Force Veterans were not included. However, prior LASSs indicated reservists who deployed in support of operations had characteristics similar to Regular Force Veterans.52

Implications for policy, services, and research

Findings that chronic pain is prevalent and that lower pain interference is associated with a variety of internal and external good well-being characteristics suggests services should address multiple well-being domains, beyond health status alone, including employment or other meaningful activity, finances, life skills/preparedness, social integration, and mastery. Findings support the concept of providing access to interprofessional support systems that can address health, occupational, physical, psychological, and socio-economic factors associated with chronic pain and pain interference with activities.46

A most interesting finding is the strong association between mastery and activities limited by pain, pointing to the potential value of longitudinal research investigating relationships between mastery, pain interference, and function. Future research could investigate whether pain management interventions that aim to increase perceived control of important aspects of life may help to improve pain interference and functioning. Future longitudinal research should include reliable and validated measures or indicators of chronic pain, pain severity, pain interference, and well-being indicators to assess the causal relationships and to evaluate change in these variables over time. Longitudinal and qualitative research to better understand the relationships between these variables is warranted.

Acknowledgments

Competing Interests

The authors have nothing to disclose.

Ethics Approval

This study was approved by the Queen’s University Health Sciences and Affiliated Teaching Hospitals Research Ethics Board, Kingston, Ontario, Canada, Apr. 14, 2021.

Informed Consent

The authors confirm that informed patient consent has been secured from all participants.

Registry and Registration No. of the Study/Trial

N/A

Animal Studies

N/A

Peer Review

This article was peer-reviewed.

Biographies

Goris Nazari, BScPT, MSc, PhD, is a physical therapist, member of the Queen’s University School of Rehabilitation Therapy, and Post-Doctoral Fellow who won a Canadian Institutes of Health Research grant for his project “Understanding patterns of healthcare utilization of Canadian Armed Forces Veterans living with chronic pain and their experiences, values, and perceived needs related to chronic pain management: A mixed methods study.”

Julián Reyes-Vélez, DVM, MSc, PhD, is a senior researcher and Epidemiologist working with the Research Directorate at Veterans Affairs Canada.

James M. Thompson, MD, is an adjunct associate professor, Department of Public Health Sciences, Queen’s University, and Assistant Professor, Department of Family Medicine, Dalhousie University. He served in the Canadian Armed Forces Reserve Force before practising family and emergency medicine and was the Research Medical Advisor at Veterans Affairs Canada. His research focus is the well-being of Canadian Armed Forces Veterans in all its forms.

Jill Sweet, MSc, is the senior statistician in the Research Directorate at Veterans Affairs Canada. She holds a MSc in statistics from Dalhousie University. Sweet has over 20 years of experience in the federal public service, including appointments at Fisheries and Oceans, the Canadian Food Inspection Agency, Canada Revenue Agency, and the Public Service Commission, and has been with the Research Directorate at Veterans Affairs since 2006.

Jordan Miller, BSc, MSc, PhD, is an assistant professor in the School of Rehabilitation Therapy at Queen’s University. His research broadly aims to reduce pain-related disability, and his research interests include interventions for people living with acute to chronic pain, improving primary care management for people with musculoskeletal conditions and pain, and knowledge translation to facilitate evidence-based management of musculoskeletal conditions and pain.

Funding Statement

No funding was received for this article.

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