Trends in the rate of depressive illness and use of antidepressant pharmacotherapy by ethnicity/race: an assessment of office-based visits in the United States, 1992-1997.

OBJECTIVE: This study was undertaken to determine ethnicity/race-specific (white, black, and Hispanic) population-adjusted rates of US office-based physician visits in which a diagnosis of a depressive disorder was recorded or in which a diagnosis of a depressive disorder was recorded and antidepressant pharmacotherapy was prescribed.

METHODS: Data from the National Ambulatory Medical Care Survey for 1992 through 1997 were partitioned into three 2-year periods: 1992-1993, 1994-1995, and 1996-1997. For each 2-year period, data from office-based physician visits for patients aged 20 to 79 years were extracted to assess, by ethnicity/race, (1) the number of visits in which a diagnosis of a depressive illness was recorded (International Classification of Diseases, Ninth Revision, Clinical Modification codes 296.2-296.36, 300.4, or 311) and (2) the number of visits in which a diagnosis of a depressive illness was recorded and antidepressant pharmacotherapy was prescribed. We calculated ethnicity/race-specific rates (per 100 US population aged 20 to 79 years) of office-based visits in which a diagnosis of a depressive disorder was recorded and in which a diagnosis of a depressive disorder was recorded and antidepressant pharmacotherapy was prescribed. The specialty of the reporting physician and the proportion of patients receiving a selective serotonin reuptake inhibitor (SSRI) were also discerned.

RESULTS: From 1992-1993 to 1996-1997, the rate of office-based visits (per 100 US population aged 20 to 79 years) in which a diagnosis of a depressive disorder was recorded increased 3.7% for whites (from 10.9 to 11.3; P = 0.001), 31.0% for blacks (from 4.2 to 5.5; P = 0.001), and 72.9% for Hispanics (from 4.8 to 8.3; P = 0.001). The rate of office-based visits in which a diagnosis of a depressive disorder was recorded and antidepressant pharmacotherapy was prescribed increased 18.5% for whites (from 6.5 to 7.7 per 100; P = 0.001), 38.5% for blacks (from 2.6 to 3.6 per 100; P = 0.001). and 106.7% for Hispanics (from 3.0 to 6.2 per 100; P = 0.001). Between 1992-1993 and 1996-1997, use of an SSRI increased among whites and blacks (from 50.0% to 65.8% and from 40.5% to 58.2%, respectively), but declined among Hispanics (from 51.4% to 48.6%; all comparisons P = 0.001).

CONCLUSION: By 1996-1997, the population-adjusted rates for Hispanics were within a quartile of those observed for whites, whereas the rates for blacks remained at less than half those observed in whites. The observed divergence in population-adjusted rates by ethnicity/race may reflect the nature of the patient-physician relationship, sensitivity and specificity of diagnostic techniques and instruments, and the wider social context in which an office-based visit occurs, including access to and type of health insurance and coverage for mental health services.