Suicide risk highest within 1 week of hospital discharge among people with depression

Key takeaways:

• Suicide incidence was highest within the first week following hospital discharge.
• Factors like alcohol and substance use disorder showed an increasing risk over time, whereas others declined or persisted.

Patients hospitalized for depression appeared at greatest risk for suicide within the first week after discharge, according to a study conducted in Finland and published in JAMA Psychiatry.

“Although incidence of suicide in depression varies remarkably temporally, risk factors have been modeled as constant and remain uncharted in the short term,” Kari Aaltonen, MD, PhD, a post-doctoral researcher in the department of psychiatry at Helsinki University Central Hospital, and colleagues wrote. “How effectively factors measured at one point in time predict risk at different time points is unknown.”

To evaluate risk factors for suicide following hospital discharge and variations in that risk over time, Aaltonen and colleagues of the population-based study analyzed data from hospital discharge, population and cause of death registers in Finland to identify all hospitalizations for depression that occurred among adults from 1996 to 2017.

The researchers calculated the incidence rate (IR) and incidence rate ratios (IRRs) for death by suicide within time periods of 0 to 3 days, 4 to 7 days, 7 to 30 days, 31 to 90 days, 91 to 365 days and 1 to 2 years following discharge.

The analysis included 193,197 hospitalizations among 91,161 patients (mean age, 44 years; 56.2% women), with total follow-up of 226,615 person-years.

In the 2-year follow-up period, 1,976 (men, n = 1,219) people died by suicide.

Results showed that the incidence of suicide was highest within the first week after discharge, with an incidence rate of 6,062 (95% CI, 4,963-7,404) per 100,000 person-years on days 0 to 3 and 3,884 (95% CI, 3,119-4,835) per 100,000 person-years on days 4 to 7, with a sharp decline after (IR for days 8 to 30 = 2,474; 95% CI, 2,197-2,786).

Researchers also found that the prevalence of suicide among men was nearly twice that of women in the first week following discharge. Specifically, incidence rates per 100,000 person-years on days 0 to 3 were 8,551 (95% CI, 6,565-11,138) among men compared with 4,359 (95% CI, 3,210-5,920) among women, with a comparable trend seen days 4 to 7 (IR for men = 5,743; 95% CI, 4,328-7,621 vs. IR for women = 2,614; 95% CI, 1,849-3,696).

The highest risk factor for death by suicide was a current suicide attempt by hanging or firearms, with incidence rate ratios of 18.9 (95% CI, 3.1-59.8) within 3 days of discharge and 10.1 (95% CI, 1.7-31.5) within 1 week.

Other risk factors associated with death by suicide within 3 days of discharge included episodes of severe (IRR = 2.18; 95% CI, 1.37-3.52) and psychotic (IRR = 2.36; 95% CI, 1.35-4.07) depression, greater symptoms and impairment on the Global Assessment Scale (eg, score 0-19: IRR = 5.26; 95% CI, 1.46-15.39), earlier suicide attempt (IRR = 2.09; 95% CI, 1.28-3.29), male sex (IRR = 1.96; 95% CI, 1.31-2.96), age older than 40 years (IRR = 2.76; 95% CI, 1.68-4.75) or 65 years (IRR = 2.45; 95% CI, 1.28-4.68), and being in the highest tertile for household disposable income (IRR = 1.99; 95% CI, 1.04-3.67).

When evaluating temporal trends for these risk factors, researchers found that incidence rate ratios remained constant for men and those with prior suicide attempts; declined for factors such as severe or psychotic depression, current suicide attempt and age; and increased for living alone, alcohol use disorder and substance use disorder.

Based on these findings, “future studies must address risk factors as temporally dynamic,” the researchers wrote.