This study used an innovative analytic approach to assess whether changes in the severity of depression were associated with comparable changes in mental health expenditures for Hispanic, African-American, and white patients followed over 2 years in primary care practices in multiple U.S. regions. Expenditures responded to changes in severity, but the degree of response overall was about half as large for minority patients as for whites. The degree of lower response is similar for Hispanics and African Americans. The effect was more consistently significant for Hispanics, presumably due to the larger number of Hispanics in our cohort.
The longitudinal analysis produced similar findings to the cross-sectional analysis, indicating that unmeasured sociodemographic factors did not substantially confound cross-sectional conclusions about differential treatment by race/ethnicity. The minimal importance of unmeasured sociodemographic factors echoes previous findings that measured sociodemographic factors do not explain disparities in depression care for Hispanics (
Lagomasino et al. 2005).
Statistical discrimination is one plausible mechanism for health care disparities, arising if health care providers are less confident of the clinical information they obtain for minority patients. In these situations, providers become more reliant on group characteristics and less sensitive to individual factors, such as changes in patient burden of illness. Our results suggest that statistical discrimination affected specialty care for depression care among minority patients but we lacked detailed data to explain how this pattern arose. Specialty mental health care depends upon a primary care physician referral, patient adherence with the referral, and specialty care decisions about the number of treatment visits. Differences by race/ethnicity at any of these steps might reduce specialty mental health expenditures for minorities. In our sensitivity analyses, we did not find evidence for differential adherence by race/ethnicity to specialist referrals.
Previous studies have demonstrated that Hispanic and African-American patients are less satisfied with health care provider communication and access to specialty care (
Morales et al. 1999;
Lurie et al. 2003;
Ayanian et al. 2005) than their white counterparts, factors which may increase statistical discrimination in minority patients. Improving communication between minority patients and their health care providers may help to reduce reliance on group characteristics in decision making for depression care and thereby improve the mental health outcomes of minority patients. It is intriguing that the MCS, a measure of severity that captures functioning as well as symptoms, is a more sensitive measure of the information that is differentially observed in communication between minority patients and their physicians, compared with the symptom-driven mCES-D, suggesting that minority patients may feel less social permission than their white counterparts to discuss how a devastating disease like depression is affecting their ability to function. Because language differences may contribute to statistical discrimination for Spanish-speaking Hispanic patients (
Baker, Hayes, and Fortier 1998;
Woloshin et al. 2001), greater availability of bilingual providers and professional translators may improve their communication with providers about the severity and treatment of depression (
Office of Minority Health 2001).
Our findings also suggest that for depression care these efforts should focus on optimizing the frequency of visits to mental health specialists, as the responsiveness of primary care visits and antidepressant medications was similar across racial/ethnic groups. Potential policy solutions include greater use of standardized depression severity measures by providers of depression care, as well as the use of trained navigators to help patients overcome barriers to seeing mental health specialists—a model currently being implemented in some centers to improve access to cancer specialists (
Dohan and Schrag 2005).
There are several limitations associated with the use of the QID data. First, patient race and ethnicity information were collected in broad, heterogeneous categories (e.g. African-American, Hispanic, white) and degree of acculturation, language, and patient-provider concordance was not assessed. Information about mental health service utilization relied on patient self-report. This data collection strategy may have led to under-reporting of service use from recall bias. However, recall bias has not been shown to vary by race/ethnicity and thus any under-report should be similar across patient groups and should not affect our results. Using data from patients voluntarily participating in a research study rather than data from a population sample limits the generalizability of findings. Finally, our measure of antidepressant expenditures did not differentiate the cost of generic vs. nongeneric drugs or specify an additional cost associated with use of multiple antidepressants at one time. However, as our interest lies in the response of severity to mental health treatment received and not in an exact quantification of resource use, our use of a single price per month for any type or number of antidepressants achieves this objective.
A particular strength of the QID cohort was that nearly all participants were insured and had some access to primary care, so the typically higher rates of uninsurance and corresponding access barriers for Hispanic and African-American patients were unlikely to have played a major role in the findings of our study.
Evidence is accumulating that statistical discrimination, emerging as a consequence of heightened clinical uncertainty about treatment for racial/ethnic minorities, plays some role in explaining the discriminatory treatment received by these groups. These findings point to the importance of supporting clinicians by improving decision making tools, including training for clinicians in collecting and interpreting information from members of minority groups, and formal decision supports that may facilitate better communication and elicitation of pertinent information. Improving patient–physician communication may improve the quality of care for all groups, and may be particularly beneficial for minority populations.