Bipolar disorder (BD) is characterized by extreme mood swings. About half of people with BD also have problems with alcohol use. Both disorders are harmful on their own, but when they occur together, the problems can be even worse.

However, the relationship between alcohol consumption and bipolar disorder is not well understood. New research has examined the link between alcohol consumption and bipolar disorder in one of the most comprehensive studies to follow a group of people with bipolar disorder over time.

A team led by Sarah Sperry, Ph.D., and Audrey Stromberg, both of the University of Michigan, and 2022 BBRF Young Investigator Ivy Tso, Ph.D., of Ohio State University, investigated how alcohol consumption affects the highs and lows of bipolar disorder and everyday life. They analyzed data from 584 people with BD who participated in the Prechter Longitudinal Study of Bipolar Disorder, which has been collecting data since 2006. Their work was published in JAMA network opened.

As the National Institute of Mental Health describes, bipolar disorder causes unusual fluctuations in mood, energy, activity levels, and concentration. These fluctuations can make it difficult to stick to routines, hold down a job, and maintain relationships. To examine how these factors might be altered by alcohol use, the study collected information on each participant’s alcohol use, depression, mania or hypomania (periods of elevated mood and increased energy), anxiety, and functioning every 6 months for at least 5 years.

The researchers also determined whether participants had bipolar disorder type I (BD I), which includes at least one manic episode (severe mood swings with symptoms such as extreme euphoria, increased self-esteem, decreased need for sleep, and rapid speech), or bipolar disorder type II (BD II), which includes at least one hypomanic episode (elevated mood of less intensity than in BD I), increased energy, and at least one major depressive episode.

When they entered the study, 42% of participants had an alcohol use disorder. Participants with BD II were more likely to continue drinking heavily than those with BD I. Individuals taking benzodiazepines were less likely to maintain high levels of alcohol consumption than those not taking these medications. Taking antipsychotics was also associated with lower alcohol consumption. However, individuals taking antidepressants tended to have greater variability in alcohol consumption.

“These medication-related findings underscore the need for careful consideration of medication regimens when treating patients with BD who drink alcohol,” noted Dr. Sperry.

The study also found that drinking more alcohol than usual was associated with increased symptoms of mania or hypomania. This association was stronger in people with BD II than in people with BD I. Importantly, manic or hypomanic episodes did not lead to increased alcohol consumption.

The study shows a clear link between increased alcohol consumption and worsening symptoms of depression and mania. Interestingly, while more frequent drinking did lead to poorer mental health, more frequent depressive or manic episodes did not cause people to drink more. Excessive alcohol consumption also had a negative impact on work performance, but did not affect other areas of life in this study, and problems at work did not cause people to drink more.

“We would have expected an increase in affective symptoms to be associated with higher alcohol consumption over time. However, we found that the opposite (i.e., increased problematic alcohol consumption) was associated with a subsequent worsening of depressive and manic or hypomanic symptoms,” notes Dr. Sperry. This pattern was consistent across all individuals and did not occur by chance.

This is the first study to examine and demonstrate differences in alcohol use between bipolar disorder subtypes BD I and BD II. The conclusion that alcohol use may contribute to mood changes and impairment in functioning is consistent with previous studies showing that people with both alcohol abuse and bipolar disorder face significant challenges—longer and more difficult alcohol withdrawal, higher treatment costs, impaired daily functioning, increased suicide risk, and poorer overall health.

Importantly, most treatments for bipolar disorder do not take alcohol consumption into account.

“Patients with BD may benefit from reduced alcohol use if their treatment goals include improving work ability and/or reducing mood symptoms, complemented by other skills to prevent future problematic drinking,” says Dr. Sperry. More research is needed to determine exactly what type of alcohol treatment would be optimal for patients with bipolar disorder.

The team also included: Melvin G. McInnis, MD, a BBRF independent investigator in 1999 and junior investigator in 1992.