Discrepant comorbidity between minority and white suicides: a national multiple cause-of-death analysis

BACKGROUND: Clinician training deficits and a low and declining autopsy rate adversely impact the quality of death certificates in the United States. Self-report and records data for the general population indicate that proximate mental and physical health of minority suicides was at least as poor as that of white suicides. METHODS: This cross-sectional mortality study uses data from Multiple Cause-of-Death (MCOD) public use files for 1999-2003 to describe and evaluate comorbidity among black, Hispanic, and white suicides. Unintentional injury decedents are the referent for multivariate analyses. RESULTS: One or more mentions of comorbid psychopathology are documented on the death certificates of 8% of white male suicides compared to 4% and 3% of black and Hispanic counterparts, respectively. Corresponding female figures are 10%, 8%, and 6%. Racial-ethnic discrepancies in the prevalence of comorbid physical disease are more attenuated. Cross-validation with National Violent Death Reporting System data reveals high relative under-enumeration of comorbid depression/mood disorders and high relative over-enumeration of schizophrenia on the death certificates of both minorities. In all three racial-ethnic groups, suicide is positively associated with depression/mood disorders whites: adjusted odds ratio (AOR) = 31.9, 95% CI = 29.80-34.13; blacks: AOR = 60.9, 95% CI = 42.80-86.63; Hispanics: AOR = 34.7, 95% CI = 23.36-51.62 and schizophrenia whites: AOR = 2.4, 95% CI = 2.07-2.86; blacks: AOR = 4.2, 95% CI = 2.73-6.37; Hispanics: AOR = 4.1, 95% CI = 2.01-8.22. Suicide is positively associated with cancer in whites AOR = 1.8, 95% CI = 1.69-1.93 and blacks AOR = 1.8, 95% CI = 1.36-2.48, but not with HIV or alcohol and other substance use disorders in any group under review. CONCLUSION: The multivariate analyses indicate high consistency in predicting suicide-associated comorbidities across racial-ethnic groups using MCOD data. However, low prevalence of documented comorbid psychopathology in suicides, and concomitant racial-ethnic discrepancies underscore the need for training in death certification, and routinization and standardization of timely psychological autopsies in all cases of suicide, suspected suicide, and other traumatic deaths of equivocal cause.