Medicare patients with schizophrenia, particularly young adults, at increased suicide risk

Medicare patients with schizophrenia had increased risk for suicide, with young adults having the highest absolute and relative risk, according to study results published in JAMA Psychiatry.

“Because schizophrenia is relatively rare and suicide is uncommon, it has been challenging to investigate the risk for suicide in people with schizophrenia,” Mark Olfson, MD, MPH, of the department of psychiatry at Columbia University Irving Medical Center, told Healio Psychiatry. “This study sought to advance our understanding of suicide risk in adults with schizophrenia as they age to help identify modifiable risk factors and inform prevention.”

Specifically, Olfson and colleagues aimed to identify suicide mortality rates (SMRs) and correlates among adults with schizophrenia across the life span, as well as to compare suicide mortality ratios for this patient population with the general United States population. Between 2007 and 2016, they identified five national retrospective longitudinal cohorts of Medicare patients with schizophrenia by age. The cohorts were ages 18 to 34 years, 35 to 44 years, 45 to 54 years, 55 to 64 years and 65 years or older. They collected death record information via the National Death Index. A total of 668,836 Medicare patients with schizophrenia (52.5% men; 47.5% women), with 2,997,308 years of follow-up and 2,218 deaths by suicide, composed the overall cohort. The researchers determined suicide mortality rates per 100,000 person-years and adjusted HRs with 95% CIs of suicide for each age group. Further, they estimated suicide SMRs for the overall cohort and by sex and age cohorts standardized to the general U.S. population according to age, race/ethnicity and sex.

Results showed a total suicide rate per 100,000 person-years of 74, which was 4.5 times higher than the rate for the general U.S. population (SMR = 4.54; 95% CI, 4.35-4.73). Men had a rate of 88.96 and women 56.33, which were 3.4 (SMR = 3.39; 95% CI, 3.22-3.57) and 8.2 (SMR = 8.16; 95% CI, 7.6-8.75) times higher, respectively, than those of the general U.S. population. Men had significantly higher suicide rates (aHR = 1.44; 95% CI, 1.29-1.61), as did those with depressive (aHR = 1.32; 95% CI, 1.17-1.5), anxiety (aHR = 1.15; 95% CI, 1.02-1.3), drug use (aHR = 1.55; 95% CI, 1.36-1.76) and sleep disorders (aHR = 1.22; 95% CI, 1.07-1.39), as well as those with suicidal ideation (aHR = 1.41; 95% CI, 1.22-1.63) and suicide attempts or self-injury (aHR = 2.48; 95% CI, 2.06-2.98).

Hispanic patients (aHR = 0.66; 95% CI, 0.54-0.8) and Black patients (aHR = 0.29; 95% CI, 0.24-0.35) had lower adjust hazards for suicide than white patients. Patients aged 18 to 34 years had a suicide rate of 141.95 (SMR = 10.19; 95% CI, 9.29-11.18) and those aged 65 years or older had a suicide rate of 24.01 (SMR = 1.53; 95% CI, 1.32-1.77). The age-associated declines per 100,000 person-years were from 153.8 for men aged 18 to 34 years to 34.17 for men aged 65 years or older and from 115.7 for women aged 18 to 34 years to 18.66 for women aged 65 years or older. The researchers noted a significant increase in the group aged 18 to 34 years in the adjusted hazards for suicide risk for patients who attempted suicide or had self-injury (aHR = 2.57; 95% CI, 18.2-2.04) and for those with comorbid drug use disorders (aHR = 1.48; 95% CI, 1.17-1.88); however, it was not increased among those with comorbid depressive disorders (aHR = 0.99; 95% CI, 0.38-1.26) during the year before follow-up began.

“Efforts to prevent suicide in this patient population should give particular attention to younger adults, most of whom are early in the course of their disorder,” Olfson said. “Within this population, those who have recent suicide attempts, suicidal ideation and co-occurring drug use disorders are at especially high risk. High rates of suicide in this population suggest a role for periodic suicide risk screening. For high-risk patients, consideration should be given to treatment with clozapine, which has anti-suicidal properties in schizophrenia, as well as adaptations of cognitive behavioral therapy, which has also shown promise.”