Background
Suicide is a major public health concern, particularly among people who use illicit substances and/or non-prescribed medications.
Objective
The present study prospectively assessed the incidence and predictors of suicidal ideation (SI) and suicide attempt (SA) among such substance-using patients over 12 months after receiving primary care.
Design
Secondary analysis of data from a randomized clinical trial of screening, brief intervention, and referral to treatment for substance use within seven public, safety-net, primary care clinics.
Participants
Adults (N=868) who used illicit drugs or non-prescribed medications at least once in the past 90 days prior to the baseline primary care visit and consented to participate.
Main Measures
At baseline, interviewers assessed demographics, psychiatric symptoms, substance use, psychosocial stressors, treatment service utilization, quality of life, past-month SI, and lifetime SA. Follow-up interviews three, six, nine, and twelve months later assessed past-month SI and any SA since the previous assessment.
Key Results
Participants reported a high incidence of SI (25.9%) and SA (7.1%) over the year following the baseline primary care visit. In univariate analyses, odds of SI or SA during the one-year follow-up were significantly elevated in patients who were female; lacked a high school diploma; were unemployed; reported depression, anxiety, hallucinations, concentration difficulty, or violent behavior in the past 30 days; used nicotine or stimulants on a daily basis; used the emergency department or mental health services in the past 90 days; reported current quality-of-life impairment in mobility or usual activities; or reported past 30-day SI or any lifetime SA at baseline. In multiple regression analyses, only past 30-day SI, any lifetime SA, past 90-day violent behavior, and current impairment due to anxiety or depression at baseline uniquely predicted SI or SA beyond other variables over the one-year follow-up.
Conclusions
Results support the need for screening for suicidality among primary care patients who use illicit substances and identify key subgroups of these patients who are at particularly elevated risk for suicidality.