Assessing depressive symptoms in persons who die of suicide in mainland China

BACKGROUND: The potential insensitivity to depression of translated diagnostic instruments makes it difficult to assess the relationship of depressive symptoms to suicide in non-Western cultures. METHODS: Addition of culturally sensitive probes and other modifications were made to the depression section of the Chinese version of the SCID; the standard SCID probes and the expanded-probes are separately used to assess each symptom of depression, the resultant diagnoses and the overall severity of depression. This modified SCID was included in the psychological autopsy interviews with family members and, separately, close associates of 887 suicides and 721 non-suicidal decedents from 23 regions of mainland China. RESULTS: Compared to the standard interview, the expanded-probe method increased reported prevalence of major depressive episode among suicide decedents from 26.4% (234/887) to 40.2% (357/887) and for other deaths from 1.0% (7/721) to 2.1% (15/701). The additional 131 cases identified using the expanded-probe method had substantial social impairment and a greatly elevated risk of suicide compared to those with no depressive symptoms (OR=37.0, 95% CI=17.6-77.6). Inter-observer reliability for major depressive episode between the two independent interviews was greater for the expanded probe method (ICC=0.77 vs. 0.67, P<0.001). For both interview methods there was a strong dose-response relationship between suicide risk and the number and severity of depressive symptoms. LIMITATIONS: This study uses proxy informants to obtain information about the psychological status of deceased subjects; the value of this expanded-probe method for the diagnosis of depression in non-Western cultures needs to be confirmed with living subjects. CONCLUSIONS: Adding culture-appropriate probes about depressive symptoms to standardized diagnostic instruments identifies many Chinese subjects with unrecognized depression. Dimensional measures of depressive symptoms are more powerful predictors of suicide risk than categorical diagnoses.