The impact of mental illness on medical illness outcomes in older adulthood, in general, has been well documented (
1–
5). However, an equally important question pertains to the patterns of mental health treatment of older adults from racial-ethnic minority groups who have a comorbid general medical illness. The association of general medical illness and mental health service use among older adults is an important area of study given the racial-ethnic disparities in receipt of health care and the overall low use of specialty mental health services in this population (
6–
10).
Previous studies have shown a positive association between general medical illness and mental health service use and expenditures (
11–
13). Sambamoorthi and colleagues (
11) found that Medicaid beneficiaries with comorbid depression and diabetes had significantly higher rates of antidepressant treatment than did patients with depression only. Similarly, Cook and colleagues (
12) found that comorbid health conditions increased the likelihood of initiation of mental health services for persons in need of care. The increased use of mental health services means a greater financial burden incurred. Psychiatric patients with a comorbid general medical illness have significantly greater mental health expenditures than patients without a comorbid general medical illness (
13).
Cook and colleagues (
12) also examined the contribution of comorbid illness to racial-ethnic disparities in mental health service use. They found that racial-ethnic disparities in access to mental health care were smaller among those with comorbid conditions than among those without them. Although their study did not specifically focus on older adults, the sample included adults age 65 and older, which suggests that the presence of a comorbid condition may predict increased engagement in mental health services among older adults from racial-ethnic minority groups. In addition, there may be an association between comorbid medical illness and reduced racial-ethnic disparities in mental health service use. Prior research has highlighted racial-ethnic disparities in mental health expenditures (
6,
14). However, those studies did not specifically address the relationship between comorbid general medical illness and disparities in mental health expenditures.
IOM Definition of Disparities and Comorbidities
According to the Institute of Medicine (IOM), disparities in health care are racial or ethnic differences in the quality of health care that are not due to clinical needs, preferences, and appropriateness of interventions (
15). To apply this conceptual model, researchers adjust for differences in clinical appropriateness, need, and preferences but not for differences resulting from other factors, such as the operation of health care systems and legal and regulatory climate discrimination. The IOM definition states that if the presence of a comorbid condition affects use only through need for care, then disparities analyses should adjust for comorbidities. However, Cook and colleagues (
12) found evidence that comorbidities can be indicative of greater exposure to the health care system. In this study, we followed this framework and allowed difference in rates of comorbidities to enter into the disparities predictions as a system-level variable.
The purpose of this study was twofold. First, we assessed the relationship between a comorbid general medical illness and mental health service use and expenditures among older adults. Second, we evaluated disparities in mental health service use and expenditures in a racially and ethnically diverse sample of older adults with and without comorbid general medical illness. The following hypotheses were tested: first, that mental health service use would be greater among mentally ill older adults with a comorbid general medical illness compared with mentally ill older adults without a comorbid general medical illness, and second, that the presence of a comorbid medical condition would be associated with reduced racial-ethnic disparities in mental health service use.
Discussion
Our results highlight the significant impact that a comorbid general medical illness has on the use of mental health services by older adults. Our hypothesis that older adults with mental illness and a comorbid general medical illness would be more likely to use mental health services was supported. We also found that expenditures, given engagement in mental health treatment, were not greater among older adults with a comorbid condition compared with older adults without one. These latter results provide preliminary evidence that mental health services for older adults are being provided equally whether or not they have a comorbid general medical condition, if they have accessed the mental health care system.
As in previous studies (
11–
13), we found that older adults with a comorbid general medical illness used mental health services at a greater rate than those without a comorbid general medical illness. The exposure hypothesis may help explain these results. It states that if physicians spend more time with specific patients because of the care needed to treat comorbid general medical conditions, then the likelihood of seeking mental health care for those in need of such care will also improve (
11–
13). In the context of our study, older adults with a chronic general medical illness may have seen their physicians more frequently, and this exposure to the health care system may have increased the likelihood that their mental health needs were recognized and treated.
In contrast to the Cook and colleagues study (
12), we did not find that the presence of a comorbid general medical condition was significantly associated with reduced racial-ethnic disparities in mental health service use. Significant racial-ethnic disparities persisted regardless of comorbidity category, and Latinos and African Americans without a comorbidity had especially low rates of mental health service use. Many older persons from racial-ethnic minority groups view use of traditional mental health services as highly stigmatizing (
25–
27). In addition, available mental health treatments may not match the preferences, values, and beliefs of older members of racial-ethnic minority groups, which can lead to the decision to not access mental health treatment (
28,
29). For Latinos and African Americans, the lack of a comorbid general medical illness may also limit exposure to the health care system. This lack of exposure, combined with the high degree of stigma and differing mental health beliefs, may contribute to the especially low rates of mental health service use among Latinos and African Americans without a comorbidity. These results underscore the need for interventions that promote greater access to mental health services among older adults from racial-ethnic minority groups and for interventions specifically designed to address their beliefs and stigmatizing attitudes toward traditional mental health services.
Effective approaches to this challenge are likely to involve using nontraditional means that are acceptable and scalable in this population. One such strategy is the use of health promotion interventions. Health promotion interventions (such as getting adequate nutrition and increasing physical activity) are behaviorally activating, bring mental health benefits to older adults faced with health-related challenges (
30–
32), and may be more desirable than treatment with medications (
28). The emphasis on treating mental health problems through health and wellness techniques could also appeal to older adults from racial-ethnic minority groups because these techniques may seem less stigmatizing and more culturally acceptable than typical mental health services (
30).
Overall, the rates of accessing mental health care were extremely low in this sample of older adults with mental health need. As with the general population, more effort should go toward encouraging access to mental health services and integrating mental health care with more often used primary care. The focus on integration may help to circumvent the lower rates of engagement in mental health services by older adults (
33,
34).
The study findings should be interpreted in the context of the limitations in our data. First, the lack of significant findings may be a result of the small sample. Although the MEPS has sufficient numbers of racial-ethnic minority cases to estimate mental health service disparities with precision, the subset we created with records for older adults (≥65) with probable mental health need was small and limited our ability to make definitive conclusions. Second, we interpreted a psychotropic medication prescription as mental health treatment. This assumption could have led to false positives because some psychotropic medications are used to treat nonpsychiatric conditions (
35,
36). Third, mental health need was determined by two brief screening measures of mental illness, not by structured diagnostic measures or measures of symptom severity. This has the potential of misrepresenting the population in need of mental health care. However, these measures have good sensitivity and specificity to diagnosis of mental disorders and nonspecific psychological distress. Fourth, because of the sample size limitations, we were unable to do a subanalysis by type of mental health services (that is, primary care versus specialty mental health care). Given that older adults from racial-ethnic minority groups tend to seek mental health services in a wider variety of settings compared with whites (
6), having one variable for mental health service use may be too broad and may mask important differences.
Despite the aforementioned limitations, our results suggest potential directions for further inquiry. For example, mental health symptom severity measures (such as the Patient Health Questionnaire–9 and the Beck Depression Inventory) as well as physiological measures (such as fasting blood glucose) could be added to track patient progress. Doing so would help determine whether the participants with comorbid conditions who are receiving versus not receiving mental health services are improving. Expanding the mental health services variable to include informal emotional support provided by family members would provide insight into the various types of mental health care that older members of racial-ethnic minority groups are receiving.