National cross-sectional cohort study of the relationship between quality of mental healthcare and death by suicide

Background Patient safety-based interventions aimed at lethal means restriction are effective at reducing death by suicide in inpatient mental health settings but are more challenging in the outpatient arena. As an alternative approach, we examined the association between quality of mental healthcare and suicide in a national healthcare system. Methods We calculated regional suicide rates for Department of Veterans Affairs (VA) Healthcare users from 2013 to 2017. To control for underlying variation in suicide risk in each of our 115 mental health referral regions (MHRRs), we calculated standardised rate ratios (SRRs) for VA users compared with the general population. We calculated quality metrics for outpatient mental healthcare in each MHRR using individual metrics as well as an Overall Quality Index. We assessed the correlation between quality metrics and suicide rates. Results Among the 115 VA MHRRs, the age-adjusted, sex-adjusted and race-adjusted annual suicide rates varied from 6.8 to 92.9 per 100 000 VA users, and the SRRs varied between 0.7 and 5.7. Mean regional-level adherence to each of our quality metrics ranged from a low of 7.7% for subspecialty care access to a high of 58.9% for care transitions. While there was substantial regional variation in quality, there was no correlation between an overall index of mental healthcare quality and SRR. Conclusion There was no correlation between overall quality of outpatient mental healthcare and rates of suicide in a national healthcare system. Although it is possible that quality was not high enough anywhere to prevent suicide at the population level or that we were unable to adequately measure quality, this examination of core mental health services in a well-resourced system raises doubts that a quality-based approach alone can lower population-level suicide rates.