Longitudinal Interplay Between Alcohol Use, Mood, and Functioning in Bipolar Spectrum Disorders.

Importance: Alcohol use disorder (AUD) is present in nearly half of individuals with bipolar disorder (BD) and is associated with markedly worsening outcomes. Yet, the concurrent treatment of BD and AUD remains neglected in both research and clinical care; characterizing their dynamic interplay is crucial in improving outcomes. Objective: To characterize the longitudinal alcohol use patterns in BD and examine the temporal associations among alcohol use, mood, anxiety, and functioning over time. Design, Setting, and Participants: This cohort study selected participants and analyzed data from the Prechter Longitudinal Study of Bipolar Disorder (PLS-BD), an ongoing cohort study that recruits through psychiatric clinics, mental health centers, and community outreach events across Michigan and collects repeated phenotypic data. Participants selected for the present study were those with a diagnosis of BD type I (BDI) or type II (BDII) who had been in the study for at least 5 years. Data used were extracted from February 2006 to April 2022, and follow-up ranged from 5 to 16 years. Main Outcomes and Measures: Alcohol use was measured using the Alcohol Use Disorders Identification Test. Depression, mania or hypomania, anxiety, and functioning were measured using the 9-Item Patient Health Questionnaire, the Altman Self-Rating Mania Scale, the 7-item Generalized Anxiety Disorder assessment scale, and the Life Functioning Questionnaire, respectively. Results: A total of 584 individuals (386 females (66.1%); mean [SD] age, 40 [13.6] years) were included. These participants had a BDI (445 [76.2%]) or BDII (139 [23.8%]) diagnosis, with or without a lifetime diagnosis of AUD, and a median (IQR) follow-up of 9 (0-16) years. More problematic alcohol use was associated with worse depressive (β = 0.04; 95% credibility interval [CrI], 0.01-0.07) and manic or hypomanic symptoms (β = 0.04; 95% CrI, 0.01-0.07) as well as lower workplace functioning (β = 0.03; 95% CrI, 0.00-0.06) over the next 6 months, but increased depressive and manic or hypomanic symptoms were not associated with greater subsequent alcohol use. These latter 2 associations were more pronounced in BDII than BDI (mania or hypomania: β = 0.16 [95% CrI, 0.02-0.30]; workplace functioning: β = 0.26 [95% CrI, 0.06-0.45]). Alcohol use was not associated with anxiety over time. Conclusions and Relevance: This study found that alcohol use, regardless of diagnostic status, was associated with mood instability and poorer work functioning in BD, but increased mood symptoms were not associated with subsequent alcohol use. Given its prevalence and repercussions, dimensional and longitudinal assessment and management of alcohol use are necessary and should be integrated into research and standard treatment of BD.