African-American women who live in rural areas have lower rates of major depressive disorder (MDD) and mood disorder compared with their urban counterparts, while rural non-Hispanic European-American women have higher rates for both than their urban counterparts, according to a new study.

Major depressive disorder is a debilitating mental illness and the prevalence of depression among both African- and Rural-Americans is understudied, according to background in the study. Addie Weaver, Ph.D., of the University of Michigan, Ann Arbor, and coauthors examined the interaction of Urban-American vs.Rural-American residence and race/ethnicity on lifetime and 12-month MDD and mood disorder in African-American and non-Hispanic European-American women.

The authors used data from the U.S. National Survey of American Life, a nationally representative household survey, which includes a substantial proportion of rural and suburban respondents, all of whom were recruited from southern states. Participants included 1,462 African-American women and 341 non-Hispanic European-American women.

Overall, when compared with African-American women, non-Hispanic European-American women had higher lifetime prevalences of MDD (21.3 percent vs. 10.1 percent) and mood disorder (21.8 percent vs. 13.6 percent). And non-Hispanic European-American women also had higher prevalences of 12-month MDD than African-American women (8.8 percent vs. 5.5 percent), according to the results.

The study also found that rural African-American women had lower prevalence rates of lifetime (4.2 percent) and 12-month (1.5 percent) MDD compared with their urban counterparts (10.4 percent and 5.3 percent, respectively). The rates were adjusted by urbanicity and race/ethnicity.

The same was true for mood disorder, with rural African-American women having lower adjusted prevalence rates of lifetime (6.7 percent) and 12-month (3.3 percent) mood disorder when compared to their urban counterparts (13.9 percent and 7.6 percent, respectively), according to the results.

However, rural non-Hispanic European-American women had higher rates of 12-month MDD (10.3 percent) and mood disorder (10.3 percent) than their urban counterparts (3.7 percent and 3.8 percent, respectively).

"These findings offer an important first step toward understanding the cumulative effect of rural residence and race/ethnicity on MDD among African-American women and non-Hispanic white women and suggest the need for further research in this area. This study adds to the small, emerging body of research on the correlates of MDD among African Americans," the study concludes.

Citation: JAMA Psychiatry. Published online April 8, 2015. doi:10.1001/jamapsychiatry.2015.10.