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RESEARCH ARTICLE |
School of Aging Studies, University of South Florida, Tampa.
Address correspondence to Jessica M. McIlvane, PhD, School of Aging Studies, University of South Florida, 4202 East Fowler Avenue, MHC1318, Tampa, FL 33620. E-mail: mcilvane{at}cas.usf.edu
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Abstract |
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Methods. Participants included 175 African American and White women (aged 45–90) who completed structured questionnaires assessing arthritis-related stress (i.e., pain, functional impairment, perceived stress), chronic life stress (i.e., discrimination, financial stress, life stressors), and well-being (i.e., depressive symptoms).
Results. African Americans reported more functional impairment and lower perceived arthritis stress, but more life stressors, financial stress, and discrimination, than Whites. Arthritis-related stress accounted for similar proportions of variance in depressive symptoms across African Americans (
R2 =.16, p <.001) and Whites (R2 =.24, p <.001). However, chronic life stressors explained significantly more variance among African Americans (R2 =.20, p <.001, vs R2 =.06, p <.05).
Discussion. Findings demonstrate the importance of considering contextual factors influencing women's health and well-being, particularly for those women with a chronic illness, including arthritis. Although arthritis-related stressors may be the predominant factors affecting well-being for Whites with arthritis, well-being in African Americans with arthritis is also closely tied to broader life stressors. Results suggest the importance of looking beyond illness-specific stressors when studying aging and health.
Key Words: Arthritis-related Stress • Chronic Life Stress • Racial Differences • Depressive Symptoms
RACIAL health disparities in health status and chronic disease persist throughout much of the life course (Ferraro & Farmer, 1996
). However, the reasons for these racial differences are complex and remain unclear. It is well established that members of minority populations in general, and African Americans in particular, are disproportionately diagnosed with more severe and debilitating illnesses, are likely to be diagnosed at a younger age with a medical disorder, and are more incapacitated from similar diseases than Whites (Bazargan & Hamm-Baugh, 1995). Explanations for these disparate rates in diagnosis and symptom management may range from institutional racism and discrimination to fewer socioeconomic resources. Documenting these sources of disparities is critical given that health disparities are embedded in larger historical, geographic, cultural, social, and economic milieus (Williams & Jackson, 2005).
An accumulating body of research on health disparities focuses on socioeconomic factors (e.g., income, education). Although socioeconomic status (SES) appears to partially explain these racial differences in health, there are cases in which racial differences persist even after controlling for SES (Williams, Yu, Jackson, & Anderson, 1997), suggesting that other factors, such as stress, may be important to consider. Chronic stressors (e.g., discrimination, financial stress), in general, are important contextual factors that may potentially have an explanatory contribution to racial differences in health and well-being, particularly stressors that may be more salient among diverse racial populations.
In the current study, we focused on arthritis, one of the most common chronic conditions in middle-aged and older women (National Academy on an Aging Society, 1999). In light of various theoretical perspectives emphasizing the importance of considering multiple chronic stressors (Antonucci & McIlvane, 2003; Moos, 2002; Pearlin, 1989), we examined the effects of both arthritis-related stressors and chronic life stressors on well-being for African American and White women. Guiding our conceptualization of stress was Lazarus and Folkman's (1984) definition, where stress involves person–environment demands that exceed an individual's resources, requires adjustments be made by the individual, and may lead to distress. Also guiding the study was Pearlin's (1989) assertion that multiple chronic stressors should be considered to capture a broader picture of the stress process. Not only are women with arthritis coping with pain and functional limitations, but they are also likely to experience other stressors in their daily lives, such as interpersonal stress and work-/home-related stress (Gignac et al., 2006). Thus, examining stress associated with chronic illness alone is not sufficient. A chronic illness, such as arthritis, does not occur in a vacuum, and it is important to consider the context in which women cope with chronic illness, which may differ based on race. However, the majority of studies on coping with arthritis have used predominantly White samples, and we are unaware of any studies that have specifically compared arthritis-related stressors and broader chronic life stressors in African American and White samples.
Racial Differences in Arthritis-Related Stressors
Recent evidence shows that African Americans face higher levels of arthritis-related stressors. African Americans report a higher prevalence of activity and work limitations, and severe pain due to arthritis (Centers for Disease Control and Prevention, 2005). They also experience more functional impairment (Kington & Smith, 1997) and lower perceived quality of life (Ibrahim, Burant, Siminoff, Stoller, & Kwoh, 2002) compared to Whites. These findings are particularly important given that arthritis-related stressors such as pain and functional limitations are related to poor psychological well-being and depression (e.g., Williamson & Schulz, 1992; Zeiss, Lewinsohn, Rohde, & Seeley, 1996).
A less studied factor, the appraisal of arthritis as stressful or not, may also be an important factor for well-being. It is well established that both the presence of stress and the perception of stress may influence one's well-being (Lazarus & Folkman, 1984). For example, when encountering a stressful situation, primary appraisal involves assessing one's risk or stake in a situation (Folkman, Lazarus, Dunkel-Schetter, DeLongis, & Gruen, 1986). The extent to which an individual perceives a stressor, such as arthritis, as harmful, threatening, challenging, or causing loss may be particularly important in terms of well-being (Folkman & Lazarus, 1985; Folkman et al., 1986). However, racial differences in primary appraisal, or the perception, of arthritis-related stress and effects on well-being among African Americans are not clear.
Racial Differences in Broader Chronic Life Stressors
African Americans, in particular, are more likely to be exposed to a variety of unique stressors, such as discrimination, low SES, and financial stress, than Whites (Anderson & Armstead, 1995; Jackson, 2002). Past research has demonstrated that these factors are related to higher levels of depressive symptoms in African Americans (Barnes et al., 2004; Schulz, Gravlee, et al., 2006; Schulz, Israel, et al., 2006). Moreover, there is a growing interest in examining the extent to which perceptions of discrimination and personal experiences of racial bias adversely affect health (Williams, Neighbors, & Jackson, 2003; Williams & Williams-Morris, 2000). The extant literature has shown that discrimination based on race and/or ethnicity leads to experienced physical and mental perturbations among diverse racial populations (Jackson, 2002). In particular, Barnes et al. found that everyday discrimination, categorized into perceptions of unfair treatment and personal rejection, was related to more depressive symptoms in both African American and White older adults.
Although the relationship between discrimination and psychological well-being (e.g., depression; Barnes et al., 2004; Schulz, Gravlee, et al., 2006) and physical health (e.g., hypertension, heart disease, diabetes; Guyll, Matthews, & Bromberger, 2001; Krieger & Sidney, 1996; Moody-Ayers, Stewart, Covinsky, & Inouye, 2005; Troxel, Matthews, Bromberger, & Sutton-Tyrrell, 2003) has been well documented, the impact of discrimination on health and psychological well-being among those with arthritis remains unclear. In the current study, we focused on everyday discrimination, which involves perceptions of unfair treatment in everyday life, such as being treated with less courtesy or respect than others.
Purpose and Hypotheses
The current study examined the effects of arthritis-related stress (i.e., pain, functional impairment, perceived stress) and chronic life stress (i.e., everyday discrimination, count of life stressors, financial stress) on depressive symptoms in African American and White women with arthritis. The primary objectives of this study were to (a) examine racial differences in levels of arthritis-related and chronic life stress, (b) assess whether the amount of variance in depressive symptoms accounted for by arthritis-related stressors is different for African Americans and Whites, and (c) assess whether the amount of variance accounted for by chronic life stressors is different for African Americans and Whites. To do this, we statistically tested whether the R2s for arthritis-related stressors and for chronic life stressors were different in African Americans compared to Whites.
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METHODS |
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We screened potential participants for eligibility either in person or by phone, and we scheduled an interview for all eligible participants. All potential participants, including both clinic and community participants, responded to the following questions in the initial screening: "What is the main kind of arthritis that you have?" "Do you have any other kinds of arthritis such as rheumatoid arthritis, psoriatic arthritis, or lupus?" and "Are you age 45 or older?" Eligibility criteria included having self-reported OA, being 
45 years of age, being female, and being cognitively intact. If a potential participant did not report having OA, then we did not include her in the study. In the clinic, we only approached patients if the doctor or nurse confirmed the OA diagnosis. In the community, we attempted to confirm the OA diagnosis by contacting each participant's doctor. Including both clinic and community participants, we were able to contact participants' rheumatologists or physicians for confirmation of their diagnosis for the majority of the sample (63%). However, for the remainder of participants, who were recruited from the community, we were not able to contact their doctor for OA diagnosis confirmation.
Interviews lasted approximately 1 hr. We obtained informed consent from all participants, and respondents received $20 for their participation. Trained interviewers conducted the majority (96%) of the interviews at the rheumatology clinic, community site (e.g., senior center), or the participant's home. In the remaining 4% of cases (n = 7), participants were not able to participate in the study due to time constraints unless they self-administered the questionnaire at home and mailed it back to the research office. In these situations, we included a letter with instructions for filling out the questionnaire. Upon receiving completed questionnaires, we made follow-up phone calls with these participants, if necessary, to clarify any unclear answers. The seven self-administered interviews were evenly distributed across the two racial groups (four Whites, three African Americans). We examined all analyses with and without these seven participants, and the results were unchanged.
Measures
Demographic variables
We measured age as a continuous variable. We assessed education by asking participants to report the highest level of education completed. We determined race by asking participants if they considered themselves to be White/Caucasian, Black/African American, Latina/Hispanic, Asian/Pacific Islander, Native American, or other.
Depressive symptoms
We measured depressive symptoms with the Center for Epidemiologic Studies–Depression scale (Radloff, 1977), a 20-item self-report scale that measures frequency of mood and behavioral symptoms occurring in the previous week. Example items include "I felt depressed" and "I enjoyed life." We reverse coded positively worded items. Items are scored on a 4-point scale ranging from 0 to 3 (rarely/none of the time, some of the time, occasionally, most of the time), scores range from 0 to 60, and high scores indicate high depressive symptoms. Reliability for the Center for Epidemiologic Studies–Depression scale was acceptable for both the African American and White samples (
s =.90 and.90, respectively).
Arthritis-Related Stressors
Arthritis-related symptoms
We measured functional impairment with the Arthritis Impact Measurement Scale 2 (AIMS2; Meenan, Mason, Anderson, Guccione, & Kazis, 1992). The AIMS2 functional impairment scale is a 28-item measure with six subscales, including mobility, walking and bending, hand and finger function, arm function, self-care, and household tasks. Possible scores range from 0 to 60, with high scores indicating poor functional status. We assessed pain with the AIMS2 5-item scale, which asks respondents to rate severity of pain, pain in two or more joints, morning stiffness, and interference with sleep. Scores range from 0 to 10, with high scores indicating greater pain. The AIMS2 assesses functional impairment and pain in the past month. Reliability was acceptable for both functional impairment (s =.92 and.91 for African Americans and Whites) and pain (s =.77 and.79 for African Americans and Whites).
Perceived arthritis stress
Four questions assessed primary appraisal (i.e., harm, threat, challenge, loss) of stress related to pain from arthritis (based on Folkman & Lazarus, 1980, as used by Schiaffino & Revenson, 1995). We asked participants to
think about a time when your pain was a moderate level of intensity or greater. When you had this pain, did you feel: 1) Harmed because it had occurred? 2) Threatened by something that might occur in the future? 3) Challenged by the situation? 4) Did you feel that something had been lost or taken away?
Responses ranged from not at all (1) to a great deal (5). Possible scores ranged from 4 to 20, with a high score indicating more perceived stress. The primary appraisal scale demonstrated acceptable reliability (s =.73 and.78 for African Americans and Whites).
Chronic Life Stressors
Everyday discrimination
We measured perceptions of everyday discrimination by using a 10-item scale that assesses discrimination without any reference to race (Williams et al., 1997). Example items include "You are treated with less courtesy than other people" and "You receive poorer service than other people at restaurants or stores." Respondents rated whether these events happened to them in their daily lives almost everyday, at least once a week, a few times a months, a few times a year, less than once a year, or never. We combined never and less than once a year and recoded the items so that scores for each item ranged from 0 to 4. Scores for the total scale ranged from 0 to 40, with a high score indicating greater perceived discrimination. After responding to the 10 questions, respondents stated if these experiences were mainly due to ancestry or national origins, gender, race, age, height or weight, shade of skin color, or other. We grouped race, ancestry or national origins, and shade of skin color together into one category. The perceived discrimination scale was reliable for both groups (s =.87 and.82 for African Americans and Whites).
Life stress
We assessed life stress by using a list of 11 life stressors taken from the National Survey of American Life (Jackson et al., 2004). Respondents indicated whether the following events had occurred during the past month (yes or no): problems with health (other than arthritis), money, job, children, family, friends, marriage, love life, police; victim of a crime; treated badly based on race. We summed items for a total count of life stressors ranging from 0 to 11.
Financial stress
A 1-item question determined financial stress: "How difficult is it for (you/your family) to meet the monthly payments on your (family's) bills?" Responses ranged from extremely difficult (5) to not difficult at all (1).
Statistical Analysis
First, we calculated descriptive statistics for the sample's demographic characteristics (age, education), arthritis-related stressors (i.e., pain, functional impairment, perceived arthritis stress), chronic life stressors (i.e., everyday discrimination, number of life stressors, financial stress), and depressive symptoms. We used t-test and chi-square analyses to determine racial differences between African Americans and Whites among the study variables.
Next, we used hierarchical regression models to examine the pattern of relationships between the predictor variables and depressive symptoms and to determine the amount of variance in depressive symptoms accounted for by arthritis-related stressors versus chronic life stressors, separately by race. The regression procedure involved entering the predictor variables in three models. We first entered demographic variables (Model I), followed by arthritis-related stressors (Model II) and chronic life stressors (Model III). We report unstandardized beta coefficients to describe the relative importance of the predictor variables within the regression model. To assess the relative percentage of variance explained in depressive symptoms across race, we calculated the confidence interval (CI) for R2 for the White sample as described in Cohen, Cohen, West, and Aiken (2003) and then examined whether the R2 for African Americans fell outside of the CI, indicating a statistical difference in the two R2s (i.e., the proportion of variance accounted for by arthritis-related stressors or by chronic life stressors was statistically different across the two racial groups).
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RESULTS |
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2 = 16.00***) and children (30% African Americans, 16% Whites; 2 = 4.57*), however there were no significant racial differences in reporting of any other individual life stressor. The majority of African Americans (82%) reported experiencing everyday discrimination at least a few times a year, compared to 63% of Whites (see Table 1). Of those reporting discrimination, African Americans were more likely to report that race was the main reason for these events, whereas Whites were more likely to choose age or other reasons. The other reasons stated by White women included (a) other people's bad attitudes (e.g., "They just had a bad day probably"), (b) job-/family-related issues (e.g., "My kids don't respect me as they should"), (c) bad customer service (e.g., "Bad customer service in stores"), and (d) own personality (e.g., "I'm assertive and people just don't know how to deal with that").
Multivariate Analysis
We used hierarchical regression models to examine the effects of arthritis-related stressors and chronic life stressors on depressive symptoms, and the unique variance accounted for by the two groups of stress variables, separately for each racial group (see Table 2). First, we entered the demographic variables (i.e., age, education) for the African American sample in Model I. Younger age (b = –0.25, p <.05) and lower education (b = –1.07, p <.001) were significantly related to higher levels of depressive symptoms in the first model and accounted for 17% of the total variance. We entered the arthritis-related stress indicators (i.e., pain, functional impairment, perceived arthritis stress) in Model II. Higher levels of perceived arthritis stress (b = 0.89, p <.01) were significantly related to more depressive symptoms, and the arthritis-related stress variables together accounted for 16% of the variance in Model II. We entered the chronic life stress variables (i.e., number of life stressors, financial stress, everyday discrimination) in Model III. Higher levels of financial stress (b = 2.55, p <.001) and more everyday discrimination (b = 0.51, p <.01) were significantly related to higher levels of depressive symptoms. Chronic life stressors accounted for an additional 20% of the variance in depressive symptoms. In the final model, when we took all of the variables into account, higher perceptions of arthritis stress, more financial strain, and more everyday discrimination were related to higher levels of depressive symptoms for African American women and accounted for 53% of the total variance in depressive symptoms.
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In order to compare the variance explained by arthritis-related stressors among the two racial groups, we first calculated the 95% CI for the R2 for the White sample (R2 =.24, CI =.09,.38). The R2 for arthritis-related stressors for the African American sample was.16, which overlapped with the CI for Whites, indicating that the variance explained for the two groups was not statistically different. We next calculated the 95% CI for chronic life stressors for the White sample (R2 =.06, CI = –.03,.16). In this case, the R2 for the African American sample, which was.20, did not overlap with the CI for the White sample. This indicates that chronic life stressors accounted for more variance in depressive symptoms for African Americans compared to Whites.
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DISCUSSION |
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For well-being, the findings suggest a different pattern of relationships for African American and White women among the arthritis stress and chronic life stress variables. Perceptions of greater stress due to arthritis, financial stress, and everyday discrimination were related to higher levels of depressive symptoms for African Americans, whereas more functional impairment and everyday discrimination were related to higher depressive symptoms for Whites. Moreover, chronic life stress accounted for more variance in depressive symptoms for African American women, whereas arthritis-related stressors accounted for similar proportions of variance across the two racial groups.
Racial Differences in Perceptions of Arthritis-Related Stress and Life Stress
Prior research has demonstrated that African Americans experience more severe arthritis-related symptoms, including more activity limitations and pain, compared to Whites (Centers for Disease Control and Prevention, 2005; Kington & Smith, 1997). However, findings are mixed, with some studies failing to find racial differences in arthritis-related symptoms (Ang, Ibrahim, Burant, & Kwoh, 2003). Accordingly, the findings from the current study reveal racial differences in functional impairment and perceived arthritis stress, but not pain. African American women reported more functional impairment compared to White women; however, we should note that in a previous analysis of these data, the racial difference in functional impairment was no longer significant when we accounted for SES (McIlvane, 2007).
In terms of perceptions of arthritis stress as being harmful, challenging, threatening, or causing loss, African American women had lower perceptions of arthritis stress compared to White women. Here we emphasize that context matters; although these findings are preliminary, it is possible that African American women have different perceptions and experiences regarding arthritis-related stress and other chronic life stressors (e.g., discrimination, financial stress) compared to White women.
To that end, African American women reported more chronic life stress than White women for every indicator, suggesting that African American women may be dealing with more outside stressors (e.g., financial stress) in addition to arthritis. Consideration of chronic life stressors that may be more salient for diverse racial groups with arthritis is particularly important, yet not often considered. Nonetheless, health reflects a social and historical pattern of differential treatment, rights, privileges, and unequal social status based on race and SES (King & Williams, 1995). For instance, the finding that African American women reported more everyday discrimination is consistent with past research (Barnes et al., 2004). However, African American women and White women attributed these events to different reasons. African American women were more likely to attribute these events to race (56% compared to 2% of White women), whereas White women were likely to attribute these events primarily to age and other reasons. Similarly, African American women reported experiencing more financial stress and other life stressors, particularly money problems and problems with children, compared to White women. Although the current study provides preliminary information on potential racial differences in perceptions of arthritis-related stress and broader chronic life stressors among women, future research should continue to focus on the relationship among these stressors and how it impacts well-being across different racial and gender groups.
Racial Differences in the Relationship Between Stress and Well-Being
A different pattern of relationships emerged between stress and well-being for African Americans compared to Whites, underscoring the importance of considering relationships among health, stress, and well-being separately for diverse racial groups (Dilworth-Anderson, Williams, & Gibson, 2002). For White women, functional impairment and everyday discrimination were related to depressive symptoms. For African American women, perceived arthritis stress, financial stress, and everyday discrimination were related to depressive symptoms. The findings also demonstrate that chronic life stressors accounted for more of the variance in depressive symptoms for African Americans than Whites, whereas arthritis-related stressors accounted for similar proportions of the variance across the two groups.
The finding that functional impairment is related to well-being for White women confirms prior research (e.g., Williamson & Schulz, 1992; Zeiss et al., 1996). Yet the question remains as to why functional impairment was not significantly related to depressive symptoms for African American women. A recent longitudinal study demonstrated that for low-SES older adults, increases in functional impairment were related to increases in depression for Whites but not for African Americans (Schieman & Plickert, 2007). To explain this finding, Schieman and Plickert suggested that African Americans are more likely to have lifetime experiences with illness and disability, whereas White women do not expect to have functional limitations. It may be that African Americans have more experience with illness, find it less distressing, and are better able to cope than Whites. This is important, considering that African Americans are disproportionately diagnosed with more severe and debilitating illnesses (Bazargan & Hamm-Baugh, 1995; Feldman & Fulwood, 1996; Gibson & Jackson, 1987).
Alternatively, African American women are more likely to be coping with multiple chronic life stressors, which may cause more distress. This is not to suggest that pain and functional impairment are unrelated to well-being in African American women; arthritis-related symptoms were related to depressive symptoms in bivariate analyses (not shown) and accounted for a similar amount of depressive symptoms among African Americans and Whites. However, it may be that other factors, such as perceptions of arthritis stress and other life stressors, need to be considered. Overall, our findings suggest that arthritis-related stressors may be the predominant factors explaining well-being for White women, whereas well-being in African American women may also be closely linked to exposure to broader chronic life stressors.
Future Research and Conclusions
The results from the current study provide preliminary evidence that different types of stressors are related to depressive symptoms for African American and White women with arthritis, highlighting the importance of contextual factors in health and aging. However, we should note several limitations. The results need to be replicated using larger, more representative samples. Specifically, the use of community- and clinic-based samples of women suggests that the results cannot be generalized to all African Americans, to all Whites, or to men. Additionally, participants self-reported having arthritis, and self-reports can be prone to bias. However, we were able to access participants' rheumatologists or physicians for further confirmation of their diagnoses for the majority of the sample (63%). The current study offers a snapshot view of stress and illness at one point in time, and the cross-sectional design limits the conclusions that can be drawn about the direction of relationships among study variables.
Some have emphasized the importance of incorporating a life-span perspective in studies that examine the influence of race and stress on health and aging (Jackson, Antonucci, & Gibson, 1990; Williams, 2002). In particular, older African American women are likely to have experienced a lifetime of discrimination, and it is important to take this into consideration in studies on health and well-being (Becker & Newsom, 2005). Racial differences in exposure to stress across the life course signify critical differences in access to care, utilization, proper diagnosis, and treatment, all of which have implications for health and well-being (Jackson, 2002). Future research needs to take a more detailed look at the accumulation of stress, complex interplay among stressors across a lifetime, and especially those stressors that may be unique to diverse racial groups and to women.
The current study highlights the complexity of capturing the stress process. For instance, we found that the number of reported chronic life stressors was unrelated to depressive symptoms for both groups. It is possible that a simple count of chronic stressors did not fully capture the day-to-day experience of stress for these two groups of women. In addition, we used a measure that assessed discrimination regardless of the cause, and, not surprisingly, the perceived reason for these events appears to be different for the two racial groups. The discrimination measure may be capturing ageism and daily hassles rather than racial discrimination for White women, because the majority attributed these events to age or other reasons.
These issues highlight an additional study limitation regarding measurement equivalence across the two racial groups. Establishing measurement equivalency is always a difficult issue requiring the use of very large sample sizes to determine if the measure is equivalent or measuring the same construct across racial groups. The small sample size in this study limits our ability to establish measurement equivalency. We also recognize that cultural differences in the interpretation of measures used in the study may contribute to our findings. However, few studies have examined the impact of perceived (or experienced) discrimination on arthritis-related symptoms, pain management, or quality of life in older patients in general, and older women with arthritis in particular. Future research efforts should continue to examine the role of discrimination and social structure in the general health and well-being of diverse racial populations with arthritis; however, studies with larger samples across racial groups will be necessary to fully address this issue.
The results from the current study have implications for future research as well as for service providers working with an increasingly diverse aging population. When considering how people adapt to arthritis, it is important not only to focus on arthritis-related symptoms but also to be aware of the impact of broader chronic life stressors. Arthritis, as well as other types of chronic illness, does not occur in a vacuum, and it is important to consider the broader social context in which people are living with chronic illness. This may be especially true for African Americans, who are more likely to experience other chronic life stressors such as discrimination and financial stress. Research on health and aging, as well as health disparities, should consider chronic life stress and the context in which women from diverse racial backgrounds are living with chronic illness.
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Acknowledgments |
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J. M. McIlvane planned the study, analyzed the data, and contributed to writing and revising the paper. T. A. Baker contributed to writing and revising the paper. C. A. Mingo wrote the Results section and contributed to revising the paper.
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Footnotes |
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Received for publication February 12, 2008. Accepted for publication June 5, 2008.
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