How does active substance use at psychiatric admission impact suicide risk and hospital length of stay?

Background/Objective: Despite their high prevalence, little is known about the effects of substance use disorders (SUD) and active substance use on the suicide risk or length of stay (LOS) of psychiatric inpatients. This study examines the relationship between active substance use at the time of psychiatric hospitalization and changes in suicide risk measures and LOS.

Methods: Admission and discharge ratings on the Suicide Status Form-II-R, diagnoses, and toxicology data from 2333 unique psychiatric inpatients were examined. Data for patients using alcohol, THC, methamphetamines, cocaine, benzodiazepines, opiates, barbiturates, PCP and multiple substances on admission were compared with data from 1426 admissions without substance use.

Results: Patients with substance use by toxicology on admission had a 0.9 day shorter LOS compared to toxicology-negative patients. During initial nurse evaluation on the inpatient unit, these patients reported lower suicide measures (i.e. suicidal ideation frequency, overall suicide risk, and wish-to-die). No significant between-group differences were seen at discharge. Patients admitted with a SUD diagnosis had a 1.0 day shorter LOS than those without, while those with a SUD diagnosis and positive toxicology reported the lowest measures of suicidality on admission. These results remained independent of psychiatric diagnosis.

Discussion: For acute psychiatric inpatients, suicide risk is higher and LOS is longer in patients with SUDs who are NOT acutely intoxicated compared with patients without a SUD. Toxicology-positive patients are less suicidal on admission and improve faster than their toxicology-negative counterparts. This study gives support to the clinical observation that acutely intoxicated patients may stabilize quickly with regard to suicidal urges and need for inpatient care.