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Abstract

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. Acknowledgements
  9. REFERENCES

Objective

To estimate, among adults ages ≥45 years with arthritis, the prevalence and correlates of 1) volunteering, 2) arthritis-attributable restrictions among volunteers, and 3) arthritis as the main barrier to volunteering (AMBV) among non-volunteers.

Methods

Data were from the 2005–2006 Arthritis Conditions Health Effects Survey, a cross-sectional random-digit–dialed national telephone survey of noninstitutionalized US adults ages ≥45 years with self-reported, doctor-diagnosed arthritis. Respondents (n = 1,793; weighted population 37.7 million) were asked if they currently volunteer (work outside the home without pay). Volunteers were asked if arthritis affects their amount or type of volunteering (arthritis-attributable volunteer limitation [AAVL]). Non-volunteers were asked if arthritis is the main reason they do not volunteer (AMBV). Univariable and multivariable-adjusted logistic regression analyses were performed to estimate associations between potential correlates and each outcome.

Results

One-third of the respondents reported volunteering. Among volunteers, 41% (4.9 million) reported AAVL. Among non-volunteers, 27% (6.8 million) reported AMBV. Fair/poor self-rated health was significantly associated with less volunteering (multivariable-adjusted odds ratio [OR] 0.5, 95% confidence interval [95% CI] 0.4–0.8) and greater AAVL (multivariable-adjusted OR 2.1, 95% CI 1.1–4.0) and AMBV (multivariable-adjusted OR 1.8, 95% CI 1.2–2.7). Poor physical function was the most strongly associated correlate of both AAVL and AMBV (multivariable-adjusted ORs 8.0 and 4.3, respectively).

Conclusion

Volunteering is an important role with individual and societal benefits, but almost 12 million adults with arthritis are limited or do not participate in volunteering due to arthritis. Individuals with restrictions in volunteering reported a substantial burden of poor physical function and may benefit from effective, underused interventions designed to improve physical function, delay disability, and enhance arthritis self-management.


INTRODUCTION

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. Acknowledgements
  9. REFERENCES

Volunteers make a substantial economic contribution to society. In 2000, US volunteer hours were estimated to correspond to $239 billion (1), and in 2002 volunteer output was estimated to equal 0.8–1.3% of the gross domestic product (2). Volunteering is also a fulfilling personal endeavor and, especially among older Americans, an important social role. Associations between volunteering and higher life satisfaction as well as positive changes in physical and psychological well-being have been demonstrated in longitudinal studies (3–6). Morrow-Howell et al suggest that “volunteering may be more beneficial to older adults with functional limitations” (7). As such, limitation in the ability to volunteer due to arthritis may be an important measure of participation restriction in a population already vulnerable to isolation.

Volunteering is generally categorized as formal (volunteering with or for a particular organization, e.g., coaching baseball for one's church) or informal (helping others who do not live in the same household, e.g., providing free childcare for a friend or neighbor). The Bureau of Labor Statistics, which does not track informal volunteering, reported that 27.9% of US adults ages ≥45 years engaged in formal volunteering between September 2005 and September 2006 (8). Another nationally representative survey found that 87% of adults ages ≥45 years volunteer (51% formal, 36% informal) (9). The Health and Retirement Survey examined volunteering among US adults ages ≥55 years and indicated that approximately 71% of adults in this age group volunteer (10% formal only, 38% informal only, 23% formal and informal) (10), including 6 in 10 adults ages ≥75 years (11). Rozario and others advocate for examining both formal and informal volunteering to provide a “fuller picture of the social engagement of baby boomers and older adults” (9, 10, 12).

Women tend to volunteer at higher rates than men across age groups, educational attainment, and other major characteristics (8). Individuals ages 35–54 years are the most likely to volunteer. Married people volunteer at a higher rate than others, and individuals with lower educational attainment volunteer at lower rates than those with more education. Employed individuals volunteer at higher rates than those who are unemployed or not in the labor force (8). Engagement in volunteering and other activities drops among people with poorer health, especially among older adults (11).

To date, to our knowledge, no studies have focused on the impact of arthritis on volunteering. Previous studies have shown that people with arthritis frequently report arthritis-attributable activity limitations (13, 14) and participation restriction in important domains, e.g., socializing (15), accessing transportation (16), social and leisure activities (17, 18), and getting around the community (16, 19). Associations between limitations, pain, joints affected, and other symptoms have been inconsistent in these studies; however, negative psychological impacts are regularly associated with arthritis (20, 21). Reported limitations in paid work have been associated with arthritis-attributable activity limitations and functional/social/leisure limitations (22). Similar to limitations in paid work (22, 23) and volunteering in general (11), we expected arthritis to have adverse impacts on volunteering and for these impacts to be more pronounced among individuals with severe pain, poor physical function, and poor self-rated health.

The purpose of this study was to describe the impact of arthritis on volunteering among adults ages ≥45 years with arthritis by estimating the prevalence and correlates of 1) volunteering, 2) arthritis-attributable restrictions in the type or amount of volunteering among adults who volunteer, and 3) arthritis as the main barrier to volunteering (AMBV) among non-volunteers.

MATERIALS AND METHODS

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. Acknowledgements
  9. REFERENCES

Data source.

Study data were obtained from the Arthritis Conditions Health Effects Survey (ACHES). ACHES was a cross-sectional random-digit–dialed telephone survey of civilian, noninstitutionalized US adults ages ≥45 years with self-reported, doctor-diagnosed arthritis (n = 1,793) (24, 25) and was designed to be representative of this population (the ACHES questionnaire is available online at: http://www.cdc.gov/arthritis/data_statistics/faqs/data_sources.htm#10). Participants were identified as having arthritis by answering “yes” to: “Have you ever been told by a doctor or other health professional that you have some form of arthritis, rheumatoid arthritis, gout, lupus, or fibromyalgia?”

ACHES was based on a complex sampling scheme. Study protocol required all age-eligible participants at each residential telephone number to be screened for arthritis eligibility. Respondents with arthritis were then interviewed by trained interviewers in English (or Spanish, as needed) between June 2005 and April 2006. The Council of American Survey Research Organizations (CASRO) (26) response rate was 51% for identifying households with at least one age-eligible resident; the overall person-level response rate was 28% (25). Of all persons identified as both age and arthritis diagnosis eligible, the ACHES interview completion rate was 69–89% across strata.

Definition of variables.

Outcome variables.

The 3 questions about volunteering were prefaced with: “These next questions refer to volunteer work, that is work outside your home for which you are not paid.”

Volunteer status.

Respondents were classified as either volunteers or non-volunteers based on their response (“yes” or “no,” respectively) to: “Do you currently do volunteer work?”

Arthritis-attributable volunteering restrictions.

Volunteers responding “yes” to “Do arthritis or joint symptoms affect the amount or type of volunteer work you do?” were identified as reporting arthritis-attributable volunteer limitation (AAVL). Non-volunteers responding “yes” to “Is arthritis or joint symptoms the main reason you do not do volunteer work?” were identified as reporting AMBV (Figure 1).

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Figure 1. Selection of the study population. The maximum number of missing values for any variable was 49 for body mass index, representing 2.7% of the overall sample. Additional missing values were: race/ethnicity (n = 43), physical function Short Form 36 score (n = 30), age (n = 24), anxiety/depression (n = 12), self-rated health (n = 5), education (n = 4), and employment (n = 2). No values were missing from the remaining variables. ACHES = Arthritis Conditions Health Effects Survey; n1 = unweighted number of respondents used for prevalence estimates and univariable models; n2 = unweighted number of respondents used in multivariable models (complete case); AAVL = arthritis-attributable volunteer limitation; AMBV = arthritis is the main barrier to volunteering.

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Potential correlates.

Potential correlates of each outcome were selected based on a known association with arthritis or the conceptual plausibility of an association with volunteering, such as the expectation that physical impairments may negatively impact volunteering (22) or that individuals with depression and arthritis may be infrequent volunteers (6, 7, 20, 21, 27).

Demographics.

Demographic variables analyzed were age, sex, race/ethnicity, education, and employment (collapsed into: “employed” [employed for pay or self-employed], “unable to work/disabled,” and “other,” a heterogeneous group comprised of those out of work, homemakers, students, and retirees).

Physical and mental health.

Respondents' ratings of their general health were collapsed into excellent/very good, good, or fair/poor. Body mass index (weight in kg/height in m2) was calculated from self-reported weight and height. Participants were asked the 10-item Short Form 36 version 2 physical functioning scale (acute version) (28). Responses were transformed to a 0–100 scale using standard methods (28), and a dichotomous physical function variable was created using the median score (sample median 50) as the cut point. Scores below the median represent poor physical function. Data on both anxiety and depression were collected using the Arthritis Impact Measurement Scales subscales (6 items per condition), and responses were transformed to a 10-point scale as directed by the instrument developers (29). Values ≥4 were classified as probable anxiety or depression, respectively (30). A combination variable was created to identify respondents with at least one of probable anxiety or depression.

Arthritis symptoms and symptom management.

Respondents rated the severity of arthritis symptoms (i.e., joint pain, joint stiffness, and arthritis-related fatigue) over the past 7 days on scale of 0 (none) to 10 (as bad as it can be). If any of the 3 symptoms were rated ≥7 (31, 32), respondents were classified as having current severe arthritis symptoms. Participants were categorized as “yes” or “no” to having taken an arthritis education class by responses to: “Have you ever taken a course or class to teach you how to manage problems related to your arthritis or joint symptoms?” Missing values for each of the arthritis symptom and symptom management variables were assigned to the most conservative category, e.g., participants without a value for daily joint pain were assigned to the “no” category.

Attitudes and confidence.

Attitude was assessed by degree of agreement with: “There is nothing a person with arthritis or joint symptoms can do to make their arthritis better.” Responses were dichotomized to: strongly disagree/disagree or neutral/agree/strongly agree. Confidence in self-management (“How confident are you that you can manage your arthritis or joint symptoms?”) was assessed using a 10-point scale, “where 0 is not at all confident and 10 is as confident as you can be.” Responses were classified as no/low/mid confidence (range 0–6) or high confidence (≥7). Missing values for attitude or confidence variables were treated as above.

Statistical analyses.

All analyses were conducted with SAS software, version 9.1 (33), using complex survey design procedures. Estimates considered unstable (i.e., with a relative standard error [RSE] ≥30%) are not reported; potentially unreliable estimates (RSE between 20% and 30%) were flagged and should be interpreted with caution. Sampling weights were applied in all of the analyses. These sampling weights were calculated by the survey vendor and were generated to address the probability of selection and to compensate for the potential biasing effect of survey nonresponse and undercoverage, a standard procedure for population-based surveys based on a complex design (34). Weights were calculated using the estimated prevalence of adults ages ≥45 years with arthritis from 2003–2005 of the National Health Interview Survey (NHIS) as the target population (25, 35). A more detailed description of sampling methods and weight calculations is available online at: http://www.cdc.gov/arthritis/data_statistics/faqs/data_sources.htm#10.

Descriptive analyses.

We estimated the prevalence of each outcome: 1) volunteering among US adults with arthritis, 2) AAVL among volunteers, and 3) AMBV among non-volunteers. Age-standardized estimates (using the projected 2000 US standard population) (36) were also calculated but were nearly identical to nonstandardized estimates and are therefore not reported. For each of the 3 outcomes, we estimated the prevalence of correlates using proportions and 95% confidence intervals (95% CIs).

Regression analyses.

The relationships between potential correlates and each outcome were estimated with odds ratios (OR) and 95% CIs in logistic regression analyses. Associations were examined in both univariable and multivariable-adjusted models.

All of the variables were examined in unadjusted analyses and were considered for inclusion in multivariable modeling, with the exception of age and sex, which were automatically included in all of the multivariable models. Multivariable models were restricted to participants with complete information for all variables of interest (i.e., complete case analysis) (Figure 1). The 3 outcome variables were separately examined in a series of forward stepwise logistic regression models using a statistical significance cutoff criterion of an alpha level of ≤0.15.

Because ACHES was designed to capture a range of arthritis impacts, including several items that are conceptually related, we examined associations among candidate variables using Pearson's correlation coefficient. Absolute r values ranged from 0.4 to 0.7, indicating modest to strong correlations between variables and, therefore, potential for colinearity in multivariable models. Consequently, we tested for colinearity using the Condition Index during forward stepwise selection; models with a Condition Index ≥30.0 were considered to have colinear terms (37). Therefore, 2 criteria were applied to terminate the forward selection modeling procedure: if no more variables were statistically significant at an alpha level of ≤0.15 or if a model had a Condition Index ≥30.0.

RESULTS

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. Acknowledgements
  9. REFERENCES

Characteristics of the sample.

The median age of participants was 62 years (range 45–99 years, SD 11.1 years). The majority of participants were women (61%) and non-Hispanic whites (81%). Less than a high school education was reported by 16% of the sample; 27% reported a college degree or more. One-third of the participants were employed. There were no statistical differences in the distribution of these characteristics within the ACHES population compared with the NHIS respondents (13), with the exception of education. ACHES respondents were slightly better educated, with fewer participants reporting less than a high school education.

Volunteering.

Approximately one-third (12.2 million [32.5%]) of all US adults ages ≥45 years with arthritis reported volunteering (Table 1). Volunteering was highest among respondents with at least a college degree (47.1%) or who were employed (38.8%), and lowest among those with less than a high school education (16.2%) or unable to work/disabled (10.0%) (Table 1).

Table 1. Prevalence and 95% confidence intervals (95% CIs) of volunteering, arthritis-attributable volunteer limitation (AAVL; among volunteers), and arthritis is the main barrier to volunteering (AMBV; among non-volunteers) among US adults ages ≥45 years with self-reported doctor-diagnosed arthritis
 VolunteersAAVL (n = 12,245)*AMBV (n = 25,451)
N in 1,000sWeighted % (95% CI)N in 1,000sWeighted % (95% CI)N in 1,000sWeighted % (95% CI)
  • *

    Weighted n in thousands.

  • Potentially unreliable relative standard error between 20% and 30%.

Total, age ≥45 years12,24532.5 (29.9–35.0)4,95440.5 (35.8–45.1)6,78626.7 (24.0–29.3)
Age, years      
 45–543,20634.4 (29.3–39.5)1,49946.8 (37.5–56.2)1,68727.6 (22.2–32.9)
 55–643,10028.8 (24.3–33.2)1,34943.5 (34.6–52.5)2,26629.5 (24.3–34.7)
 ≥655,68833.3 (29.5–37.1)1,98434.9 (28.3–41.5)2,72723.9 (20.1–27.7)
Sex      
 Male5,21735.5 (31.0–40.1)2,04439.2 (31.3–47.1)2,09022.1 (17.5–26.7)
 Female7,02830.5 (27.8–33.3)2,91041.4 (36.0–46.8)4,69529.4 (26.1–32.7)
Race/ethnicity      
 Non-Hispanic white10,22434.4 (31.5–37.4)4,07039.8 (34.7–44.9)4,51723.2 (20.2–26.2)
 Non-Hispanic black80622.7 (16.7–28.7)35644.1 (28.1–60.2)1,04337.9 (29.7–46.2)
 Hispanic50822.0 (12.6–31.3)25049.2 (25.3–73.0)75041.5 (29.9–53.1)
 Non-Hispanic other42832.9 (20.3–45.6)22251.9 (29.1–74.8)23627.0 (13.1–41.0)
Education      
 Less than high school95016.2 (11.1–21.3)48551.1 (33.5–68.6)1,98640.5 (33.8–47.2)
 High school graduate6,50330.2 (27.0–33.4)2,90144.6 (38.5–50.8)3,88925.8 (22.4–29.2)
 College or more4,79347.1 (41.8–52.5)1,56732.7 (25.1–40.3)84215.7 (10.9–20.4)
Employment status      
 Employed4,85238.8 (34.1–43.4)1,83237.8 (30.4–45.2)94412.3 (8.4–16.2)
 Unable to work/disabled55010.0 (6.1–13.9)38570.1 (52.7–87.4)2,93559.5 (52.9–66.2)
 Other6,81834.7 (31.2–38.2)2,73640.1 (34.0–46.3)2,90722.7 (19.1–26.2)

The distribution of volunteers and non-volunteers did not differ by age or sex, but a smaller proportion of volunteers had less than a high school education compared with non-volunteers (7.8% versus 19.4%) (Table 2). Compared with non-volunteers, volunteers more frequently reported high confidence in self-management (67.5% versus 59.2%) and above median physical function (68.5% versus 44.2%) and had lower prevalence of fair/poor health (18.1% versus 41.8%), probable anxiety/depression (22.9% versus 38.3%), or current severe arthritis symptoms (29.5% versus 50.7%) (Table 2).

Table 2. Association between volunteer status and selected characteristics among US adults ages ≥45 years with self-reported doctor-diagnosed arthritis*
 Non-volunteer (n = 25,451), weighted % (95% CI)Volunteer (n = 12,245), weighted % (95% CI)Univariable OR (95% CI)Multivariable OR (95% CI)
  • *

    Numbers may not sum to 100 due to rounding. 95% CI = 95% confidence interval; OR = odds ratio; SF-36 = Short Form 36.

  • Weighted n in thousands.

  • Multivariable models were restricted to a complete case analysis and only contain variables that satisfied the model selection criteria.

  • §

    Potentially unreliable relative standard error between 20% and 30%.

Total67.5 (65.0–70.1)32.5 (30.0–35.0)  
Demographics    
 Age, years    
  45–5424.3 (21.6–27.0)26.7 (22.3–31.1)1.01.0
  55–6430.5 (27.5–33.5)25.8 (21.7–30.0)0.7 (0.5–1.0)0.8 (0.6–1.1)
  ≥6545.2 (42.0–48.5)47.4 (42.5–52.3)0.9 (0.7–1.2)1.1 (0.8–1.5)
 Sex    
  Male37.2 (34.2–40.2)42.6 (38.1–47.1)1.01.0
  Female62.8 (59.8–65.8)57.4 (52.9–61.9)0.8 (0.6–1.0)0.9 (0.7–1.1)
 Race/ethnicity    
  Hispanic7.3 (5.5–9.0)4.2 (2.3–6.2)§0.7 (0.4–1.2)
  Non-Hispanic white78.2 (75.8–80.6)85.4 (82.6–88.3)1.0
  Non-Hispanic black11.0 (9.4–12.7)6.7 (5.1–8.4)0.6 (0.4–0.8)
  Non-Hispanic other3.5 (2.3–4.7)3.6 (2.0–5.2)§1.0 (0.6–1.7)
 Education    
  Less than high school19.4 (16.9–21.9)7.8 (5.1–10.4)0.5 (0.3–0.7)0.6 (0.4–0.9)
  High school graduate59.4 (56.2–62.6)53.1 (48.3–57.9)1.01.0
  College or more21.2 (18.5–23.9)39.1 (34.4–43.9)2.0 (1.5–2.7)1.5 (1.1–2.0)
 Employment status    
  Employed30.1 (27.2–33.1)39.7 (34.9–44.5)1.2 (1.0–1.6)
  Unable to work/disabled19.4 (16.9–21.9)4.5 (2.7–6.3)§0.2 (0.1–0.3)
  Other50.5 (47.2–53.7)55.8 (50.9–60.6)1.0
Physical and mental health    
 Self-rated health in general    
  Excellent/very good28.0 (25.2–30.9)46.3 (41.5–51.1)1.4 (1.1–1.9)1.2 (0.9–1.5)
  Good30.2 (27.3–33.1)35.5 (31.1–40.0)1.01.0
  Fair/poor41.8 (38.7–44.9)18.1 (14.5–21.7)0.4 (0.3–0.5)0.5 (0.4–0.8)
 Body mass index, kg/m2    
  Under/healthy weight (≤24.9)30.2 (27.2–33.1)29.1 (25.0–33.3)1.0
  Overweight (25.0–29.9)33.9 (31.0–37.0)43.5 (38.9–48.1)1.4 (1.1–1.9)
  Obese (≥30.0)35.9 (32.8–38.9)27.4 (23.4–31.5)0.8 (0.6–1.1)
 Physical function (by SF-36 score)    
  Poor (below median)55.8 (52.6–58.9)31.5 (27.2–35.9)0.4 (0.3–0.5)0.6 (0.4–0.7)
  Above median44.2 (41.1–47.4)68.5 (64.1–72.8)1.01.0
 Probable anxiety/depression    
  Yes38.3 (35.2–41.4)22.9 (19.0–26.8)0.5 (0.4–0.6)
  No61.7 (58.6–64.8)77.1 (73.2–81.0)1.0
Arthritis symptoms and symptom management    
 Daily joint pain (pain on 7 of the past 7 days)    
  Yes63.2 (60.2–66.3)53.5 (48.8–58.3)0.7 (0.5–0.9)
  No36.8 (33.7–39.8)46.5 (41.7–51.2)1.0
 Current severe arthritis symptoms    
  Yes50.7 (47.5–53.9)29.5 (25.4–33.7)0.4 (0.3–0.5)
  No49.3 (46.1–52.5)70.5 (66.3–74.6)1.0
 Arthritis education class    
  Yes8.8 (7.0–10.5)11.7 (8.8–14.7)1.4 (1.0–2.0)
  No91.2 (89.5–93.0)88.3 (85.3–91.2)1.0
Attitudes and confidence    
 There is nothing a person with arthritis or joint symptoms can do to make their arthritis better    
  Disagree/strongly disagree61.4 (58.3–64.5)74.0 (70.0–78.1)1.7 (1.3–2.3)1.3 (1.0–1.7)
  Neutral/agree/strongly agree38.6 (35.5–41.7)26.0 (21.9–30.0)1.01.0
 Confidence in self-management of symptoms    
  High confidence59.2 (56.1–62.2)67.5 (63.1–71.9)1.4 (1.1–1.8)
  No/low/mid confidence40.8 (37.8–43.9)32.5 (28.1–36.9)1.0

In both univariable and multivariable analyses, less than a high school education, fair/poor health, and poor physical function were each associated with lower likelihood of volunteering (univariable ORs 0.5, 0.4, and 0.4; multivariable-adjusted ORs 0.6, 0.5, and 0.6, respectively) (Table 2). Having at least a college degree was associated with an increased likelihood of volunteering in both the univariable and multivariable analysis (multivariable-adjusted OR 1.5, 95% CI 1.1–2.0) (Table 2).

AAVL.

Among volunteers, 40.5% (∼5 million people) reported AAVL, with the highest prevalence among those who were unable to work/disabled (70.1%) (Table 1). There were no differences in prevalence of AAVL by age, sex, race/ethnicity, or education (Table 1), and there were no statistically significant differences in the distribution of these characteristics among volunteers with and without AAVL (Table 3).

Table 3. Association between arthritis-attributable volunteer limitation (AAVL) and selected characteristics among US adults ages ≥45 years with self-reported doctor-diagnosed arthritis*
 No AAVL (n = 7,292), weighted % (95% CI)AAVL (n = 4,954), weighted % (95% CI)Univariable OR (95% CI)Multivariable OR (95% CI)
  • *

    Numbers may not sum to 100 due to rounding. 95% CI = 95% confidence interval; OR = odds ratio; SF-36 = Short Form 36.

  • Weighted n in thousands.

  • Multivariable models were restricted to a complete case analysis and only contain variables that satisfied the model selection criteria.

  • §

    Potentially unreliable relative standard error between 20% and 30%.

  • Unstable relative standard error ≥30.0%.

Total59.5 (54.9–64.2)40.5 (35.8–45.1)  
Demographics    
 Age, years    
  45–5423.8 (18.4–29.3)31.0 (23.9–38.1)1.01.0
  55–6424.4 (19.3–29.6)27.9 (21.2–34.7)0.9 (0.5–1.5)0.8 (0.4–1.6)
  ≥6551.7 (45.3–58.1)41.1 (33.5–48.6)0.6 (0.4–1.0)0.4 (0.2–0.7)
 Sex    
  Male43.5 (37.7–49.4)41.3 (33.9–48.6)1.01.0
  Female56.5 (50.6–62.3)58.7 (51.4–66.1)1.0 (0.6–1.5)0.7 (0.4–1.1)
 Race/ethnicity    
  Hispanic3.7 (1.5–5.8)§0.9 (0.4–2.3)
  Non-Hispanic white87.1 (83.7–90.4)83.1 (78.0–88.2)1.0
  Non-Hispanic black6.4 (4.2–8.5)7.3 (4.6–9.9)1.3 (0.7–2.5)
  Non-Hispanic other1.1 (0.5–2.8)
 Education    
  Less than high school6.4 (3.2–9.6)§9.8 (5.4–14.2)§1.3 (0.6–2.8)1.4 (0.6–3.5)
  High school graduate49.4 (43.3–55.5)58.6 (51.0–66.1)1.01.0
  College or more44.2 (38.1–50.4)31.6 (24.4–38.9)0.6 (0.4–0.9)0.8 (0.5–1.4)
 Employment status    
  Employed41.6 (35.3–47.9)37.0 (29.9–44.1)1.0 (0.6–1.5)
  Unable to work/disabled7.8 (3.9–11.7)§3.3 (1.3–8.7)
  Other56.2 (49.9–62.5)55.2 (47.9–62.6)1.0
Physical and mental health    
 Self-rated health in general    
  Excellent/very good56.7 (50.7–62.8)31.0 (24.1–37.9)0.5 (0.3–0.7)0.7 (0.4–1.1)
  Good34.3 (28.5–40.1)37.4 (30.3–44.5)1.01.0
  Fair/poor9.0 (6.0–11.9)31.6 (24.6–38.7)3.5 (2.0–6.3)2.1 (1.1–4.0)
 Body mass index, kg/m2    
  Under/healthy weight (≤24.9)32.8 (27.4–38.1)23.6 (17.2–30.0)1.0
  Overweight (25.0–29.9)46.8 (40.9–52.8)38.4 (31.0–45.8)1.1 (0.7–1.8)
  Obese (≥30.0)20.4 (15.8–25.0)38.0 (30.8–45.1)2.4 (1.5–4.1)
 Physical function (by SF-36 score)    
  Poor (below median)12.8 (9.2–16.3)59.3 (51.8–66.8)10.8 (6.8–17.2)8.0 (4.9–13.1)
  Above median87.2 (83.7–90.8)40.7 (33.2–48.1)1.01.0
 Probable anxiety/depression    
  Yes14.6 (10.5–18.3)35.2 (28.2–42.2)3.2 (2.0–5.0)
  No85.4 (81.3–89.5)64.8 (57.8–71.8)1.0
Arthritis symptoms and symptom management    
 Daily joint pain (pain on 7 of the past 7 days)    
  Yes44.2 (38.0–50.4)67.3 (60.3–74.3)2.4 (1.6–3.6)
  No55.8 (49.6–62.0)32.7 (25.7–39.7)1.0
 Current severe arthritis symptoms    
  Yes20.3 (15.6–25.0)43.1 (35.9–50.2)2.9 (1.2–4.5)1.9 (1.1–3.1)
  No79.7 (75.0–84.4)56.9 (49.8–64.1)1.01.0
 Arthritis education class    
  Yes9.4 (6.2–12.6)15.2 (9.7–20.6)1.7 (0.9–3.0)
  No90.6 (87.4–93.8)84.8 (79.4–90.3)1.0
Attitudes and confidence    
 There is nothing a person with arthritis or joint symptoms can do to make their arthritis better    
  Disagree/strongly disagree77.0 (71.9–82.2)72.6 (66.1–79.1)0.7 (0.5–1.2)
  Neutral/agree/strongly agree23.0 (17.8–28.1)27.4 (20.9–33.9)1.0
 Confidence in self-management of symptoms    
  High confidence75.1 (69.7–80.5)57.6 (50.3–65.0)0.4 (0.3–0.7)0.7 (0.4–1.1)
  No/low/mid confidence24.9 (19.5–30.3)42.4 (35.0–49.7)1.01.0

Compared with non-AAVL respondents, those with AAVL reported poor physical function more than 4 times as often (59.3% versus 12.8%) (Table 3) and more frequently reported probable anxiety/depression (35.2% versus 14.6%), daily joint pain (67.3% versus 44.2%), and current severe arthritis symptoms (43.1% versus 20.3%) (Table 3). High confidence in symptom management was reported by 75.1% of non-AAVL respondents compared with only 57.6% of those with AAVL (Table 3).

In univariable models, individuals unable to work/disabled and those reporting fair/poor health, poor physical function, and probable anxiety/depression were at least 3 times more likely to report AAVL than their respective counterparts (Table 3). Poor physical function was the characteristic most strongly associated with AAVL in both univariable (OR 10.8, 95% CI 6.8–17.2) and multivariable-adjusted models (OR 8.0, 95% CI 4.9–13.1) (Table 3). Respondents in the oldest age group were less likely to report AAVL (multivariable-adjusted OR 0.4, 95% CI 0.2–0.7) (Table 3).

AMBV.

Among non-volunteers, 26.7% (6.8 million people) reported AMBV (Table 1). The highest prevalence of AMBV was among those unable to work/disabled (59.5%), followed by Hispanics (41.5%) and those with less than a high school education (40.5%) (Table 1). Employed persons and those with at least a college degree reported the lowest AMBV prevalence (12.3% and 15.7%, respectively) (Table 1). There were no statistically significant differences in the prevalence of AMBV by age or sex (Table 1).

AMBV respondents indicated approximately twice the frequency of fair/poor health compared with those not reporting AMBV (67.6% versus 32.5%) (Table 4). A larger and statistically significant proportion of those with AMBV also had poor physical function (87.7% versus 44.2%), probable anxiety/depression (58.3% versus 31.0%), daily joint pain (81.1% versus 56.7%), and current severe arthritis symptoms (83.9% versus 38.7%) compared with non-AMBV respondents (Table 4).

Table 4. Association between arthritis as the main barrier to volunteering (AMBV) and selected characteristics among US adults ages ≥45 years with self-reported doctor-diagnosed arthritis*
 No AMBV (n = 18,665), weighted % (95% CI)AMBV (n = 6,786), weighted % (95% CI)Univariable OR (95% CI)Multivariable OR (95% CI)
  • *

    Numbers may not sum to 100 due to rounding. 95% CI = 95% confidence interval; OR = odds ratio; SF-36 = Short Form 36.

  • Weighted n in thousands.

  • Multivariable models were restricted to a complete case analysis and only contain variables that satisfied the model selection criteria.

  • §

    Potentially unreliable relative standard error between 20% and 30%.

Total73.3 (70.7–76.0)26.7 (24.0–29.3)  
Demographics    
 Age, years    
  45–5423.9 (18.4–29.3)25.3 (20.2–30.3)1.01.0
  55–6429.2 (19.3–29.6)33.9 (28.2–39.6)1.1 (0.7–1.6)1.4 (0.9–2.2)
  ≥6546.8 (45.3–58.1)40.8 (35.1–46.5)0.8 (0.5–1.1)0.8 (0.5–1.3)
 Sex    
  Male39.5 (37.7–49.4)30.8 (25.2–36.5)1.01.0
  Female60.5 (50.6–62.3)69.2 (63.5–74.8)1.5 (1.1–2.1)1.1 (0.7–1.6)
 Race/ethnicity    
  Hispanic5.8 (3.9–7.6)11.5 (7.7–15.2)2.6 (1.5–4.5)
  Non-Hispanic white81.5 (78.9–84.1)69.0 (64.1–74.0)1.0
  Non-Hispanic black9.3 (7.6–11.0)15.9 (12.3–19.5)1.9 (1.3–2.7)
  Non-Hispanic other3.5 (2.0–4.9)§3.6 (1.6–5.6)§1.3 (0.7–2.7)
 Education    
  Less than high school15.7 (13.0–18.4)29.6 (24.4–34.8)2.1 (1.5–3.0)
  High school graduate60.0 (56.2–63.7)57.9 (52.2–63.6)1.0
  College or more24.4 (21.0–27.7)12.5 (8.7–16.4)0.5 (0.3–0.7)
 Employment status    
  Employed36.1 (32.4–39.7)13.9 (9.6–18.2)0.4 (0.3–0.6)
  Unable to work/disabled10.7 (8.4–13.0)43.2 (37.4–49.0)5.4 (3.7–7.9)
  Other53.2 (49.4–57.0)42.8 (37.1–48.6)1.0
Physical and mental health    
 Self-rated health in general    
  Excellent/very good34.3 (30.7–37.9)10.7 (7.3–14.2)0.5 (0.3–0.8)0.7 (0.4–1.3)
  Good33.2 (29.7–36.7)21.6 (16.7–26.6)1.01.0
  Fair/poor32.5 (29.0–35.9)67.6 (62.2–73.1)3.4 (2.4–5.0)1.8 (1.2–2.7)
 Body mass index, kg/m2    
  Under/healthy weight (≤24.9)31.9 (28.3–35.4)25.5 (20.3–30.7)1.0
  Overweight (25.0–29.9)35.3 (31.7–39.0)30.2 (24.7–35.7)1.0 (0.7–1.5)
  Obese (≥30.0)32.8 (29.3–36.4)44.3 (38.4–50.2)1.8 (1.3–2.6)
 Physical function (by SF-36 score)    
  Poor (below median)44.2 (40.5–47.9)87.7 (83.8–91.6)8.7 (5.7–13.1)4.3 (2.7–6.8)
  Above median55.8 (52.1–59.5)12.3 (8.4–16.2)1.01.0
 Probable anxiety/depression    
  Yes31.0 (27.6–34.4)58.3 (52.6–64.0)3.1 (2.4–4.1)
  No69.0 (65.6–72.4)41.7 (36.0–47.4)1.0
Arthritis symptoms and symptom management    
 Daily joint pain (pain on 7 of the past 7 days)    
  Yes56.7 (53.0–60.4)81.1 (76.5–85.7)3.4 (2.3–4.9)
  No43.3 (39.6–47.0)18.9 (14.3–23.5)1.0
 Current severe arthritis symptoms    
  Yes38.7 (35.1–42.3)83.9 (79.9–87.9)8.3 (5.8–11.9)4.0 (2.7–6.0)
  No61.3 (57.7–64.9)16.1 (12.1–20.1)1.01.0
 Arthritis education class    
  Yes6.5 (4.7–8.4)14.8 (10.7–19.0)2.5 (1.6–4.0)
  No93.5 (91.6–95.3)85.2 (81.0–89.3)1.0
Attitudes and confidence    
 There is nothing a person with arthritis or joint symptoms can do to make their arthritis better    
  Disagree/strongly disagree66.3 (62.7–69.8)48.0 (42.1–53.8)0.4 (0.3–0.6)0.6 (0.4–0.9)
  Neutral/agree/strongly agree33.7 (30.2–37.3)52.0 (46.2–57.9)1.01.0
 Confidence in self-management of symptoms    
  High confidence64.5 (60.9–68.1)44.5 (38.8–50.1)0.4 (0.3–0.5)
  No/low/mid confidence35.5 (31.9–39.1)55.5 (49.9–61.2)1.0

The strongest associations in the univariable models were between AMBV and poor physical function (OR 8.7), followed by current severe arthritis symptoms (OR 8.3) and being unable to work/disabled (OR 5.4) (Table 4). Poor physical function and current severe arthritis symptoms remained strongly associated with AMBV in the multivariable-adjusted model (ORs 4.3 and 4.0, respectively) (Table 4). In the multivariable model, respondents who disagreed with the attitude statement (nothing can be done to make arthritis better) were 40% less likely than those who agreed or were neutral to report AMBV (OR 0.6, 95% CI 0.4–0.9) (Table 4).

DISCUSSION

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. Acknowledgements
  9. REFERENCES

Adults ages ≥45 years with arthritis who do volunteer are similar to other volunteers in that volunteering is more common among women than men, lowest among those with low education, and least likely among those with fair/poor health. Among volunteers, AAVL was surprisingly least likely for the oldest age group, but age had no effect on AMBV among non-volunteers. Neither AAVL nor AMBV was associated with sex, education, or employment in multivariate models, characteristics frequently associated with volunteering. Inconsistent with expectations based on the volunteer literature, probable anxiety/depression was not associated with any outcome in multivariate models.

Nearly one-third (32.5%) of US adults ages ≥45 years with arthritis volunteer. When the ACHES sample is restricted to respondents ages ≥55 years, the prevalence of volunteering is 28.6% (95% CI 28.6–34.4). There is a substantial difference in magnitude between volunteer prevalence among ACHES respondents compared with other sources that report formal and informal volunteering, suggesting volunteering may be less frequent among people with arthritis. (Figure 2). Often, people with arthritis employ the adaptive strategy of reducing discretionary activities (e.g., socializing, leisure activities, volunteering, and activities for relaxation or pleasure) to conserve time and energy for committed activities (associated with social identity and “principle productive roles,” e.g., paid work, family care) and obligatory activities (required for self-sufficient survival, e.g., activities of daily living, self-care, and hygiene, as defined by Verbrugge et al) (38).

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Figure 2. Prevalence of volunteering among US adults by type, source, and age group. * = Arthritis Conditions Health Effects Survey (ACHES), ages ≥45 years with self-reported doctor-diagnosed arthritis, “work outside your home for which you are not paid”; † = time and money (T&M), an in-depth look at ≥45 volunteers and donors, ages ≥45 years (9); formal = volunteering with or for a particular organization; informal = helping others who do not live in the same household; ‡ = ACHES, ages ≥55 years with self-reported doctor-diagnosed arthritis, “work outside your home for which you are not paid”; § = Health and Retirement Survey (HRS), ages ≥55 years (10).

Download figure to PowerPoint

For example, in a study examining behavioral modifications for valued life activities among people with rheumatoid arthritis (RA), 53% of participants reported limiting their amount of volunteering (39). The same pattern was found in a similar study of people with systemic lupus erythematosus (40). In an osteoarthritis (OA) study, use of selection (forgoing activities) was associated with having fewer social resources, greater perceptions of OA impact, and greater personal care disability (41), suggesting that selection is often used by an already isolated group. As noted in these studies, the choice to spend more time on certain activities to accommodate effects of arthritis necessitates less time for other activities. Selection may force individuals to limit or give up valued activities, effectively contracting the scope of potential activities in which people participate (39).

Katz and Morris observed that women with RA who had more severe functional limitations shifted time away from “committed” and “discretionary” activities toward “obligatory” activities and that this shift was associated with psychological distress, and concluded that there is a need “to maintain important productive, social and discretionary activities,” including volunteering (42). More telling, in a longitudinal study of older adults with OA, Machado et al demonstrated evidence suggesting a pathway from arthritis symptoms to changes in mood that ultimately affect participation (43).

A better understanding of how people with arthritis select “discretionary” activities to relinquish and how physical limitations and demands drive these choices is needed (44). In a recent OA study, participants were more likely to report arthritis as intrusive or disruptive to their lives when it interfered with roles they rated as important (45). These findings by Gignac et al suggest that, although we do not have direct evidence that volunteering is an important role among AAVL and AMBV respondents, those who do not value volunteering are less likely to report that arthritis limits their volunteer participation and that respondents who do value volunteering may be more likely to perceive arthritis as disruptive to this pursuit.

Because there may be a hierarchy in the “chipping away” of participation in valued activities, beginning with “discretionary” and eventually affecting “committed” and “obligatory” domains, asking arthritis patients about their participation in activities and any changes in their behavior may be useful clinical shorthand to identify patients at increased risk for restriction, depression, and even job loss. Public health interventions, too, must be designed and applied in ways that complement clinical efforts, for example, by bolstering self-management education and communication skill building. Almost three-quarters of AAVL and nearly half of AMBV individuals reject the nihilistic attitude statement that nothing can be done for arthritis, suggesting that these groups may be an ideal target population for evidence-based arthritis self-management education and physical activity interventions, which have been shown to be effective in reducing physical and functional limitations, decreasing pain, and delaying disability due to arthritis (46).

Study findings are subject to at least 5 limitations. First, respondents self-reported a doctor diagnosis of arthritis, which may be subject to recall bias. However, this arthritis case finding question appears valid for public health surveillance (47, 48). Second, study data are cross-sectional in nature and cannot be used to infer causation. Third, the definition of volunteering used in this study does not include volunteer activities that take place in the home, e.g., via the computer. Next, AMBV prevalence may be overestimated due to potential social desirability bias. Even so, the high proportions of fair/poor health (68%), poor physical function (88%), daily joint pain (81%), and current severe arthritis symptoms (84%) among those reporting AMBV clearly demonstrate a life-altering arthritis impact. Finally, the CASRO response rate for the survey overall was low, which is consistent with declining contact and cooperation rates for national random-digit–dial surveys in general (49, 50). Despite low response, this study's results appear generalizable to the target population. The distribution of age, sex, race/ethnicity, and employment status among weighted ACHES respondents and the target population (as measured by the NHIS, an accepted standard for public health surveillance) are almost identical (25), suggesting that the ACHES results are nationally representative of US adults ages ≥45 years with arthritis.

This study also has important strengths. To our knowledge, ACHES is the first survey to collect detailed information on volunteering among adults with arthritis and to ask respondents about the relationship between their arthritis and their ability to volunteer. This unique survey allows us to add to the literature examining arthritis impact. Next, our measures specifically ask respondents if they attribute their limitation or barrier to volunteering to their arthritis, which provides valuable insight regarding individuals' perceptions of arthritis impact on their lives. Third, the extensive range of information obtained from ACHES respondents enabled us to examine multiple aspects of participation restriction and disability among people with arthritis within the context of volunteering. Finally, volunteering is a particularly important activity for older persons and those retired from the work force (3), so the ACHES sample (adults ages ≥45 years) is an ideal population in which to explore the impact of arthritis on volunteering.

Limitations in volunteering are common among adults with arthritis. To the extent that people with arthritis are limited or cannot participate in volunteering because of their arthritis, we have an opportunity to assist them in gaining skills to allow them to participate as they choose to in volunteer activities. People who have said that arthritis limits their volunteering or is the only reason they do not volunteer represent an unmet need in terms of receiving clinical and public health interventions designed and demonstrated to improve function, delay disability, and increase quality of life. Ultimately, we need to know what matters to people with arthritis and how arthritis affects these roles and domains. Future research findings refining arthritis impact can then be used to design, develop, and target effective interventions to minimize arthritis impact and position people with arthritis to make satisfying, self-directed choices about participation in volunteer and other valued activities.

AUTHOR CONTRIBUTIONS

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. Acknowledgements
  9. REFERENCES

All authors were involved in drafting the article or revising it critically for important intellectual content, and all authors approved the final version to be submitted for publication. Ms Theis had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Study conception and design. Theis, Murphy, Hootman, Helmick, Sacks.

Acquisition of data. Theis, Hootman.

Analysis and interpretation of data. Theis, Murphy, Hootman, Helmick, Sacks.

Acknowledgements

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. Acknowledgements
  9. REFERENCES

We thank Dr. Matthew Zack for providing consultation on regression analyses.

REFERENCES

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. Acknowledgements
  9. REFERENCES
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