Despite the argument that psychiatric treatment helps prevent suicide in major mental illnesses, new research shows that suicide is the most common cause of death for those with bipolar disorder (BD), even after treatment. And despite the argument that those who die by suicide are likely to be “off their meds,” the data shows that 48% of those who died by suicide did so specifically by overdosing on their psychiatric drugs.
The researchers found that people treated for bipolar disorder were six times more likely to die from accidents or suicide (external causes) and twice as likely to die of health problems (somatic causes) than the general population.
“Individuals with BD had sixfold higher mortality due to external causes and twofold higher mortality due to somatic causes,” the researchers write.
The study, published in BMJ Mental Health, was led by Tapio Paljärvi at Niuvanniemi Hospital, Finland, and included researchers from the University of Eastern Finland, Karolinska Institute in Sweden, the University of Southern Denmark, and the Oxford University, UK.
The researchers included 47,018 people with bipolar disorder, identified through a Finnish nationwide registry that lists people with that diagnosis from inpatient hospitalizations and outpatient centers (thus, the participants were those who specifically received intensive treatment for BD). The participants were all diagnosed with BD between 1998 and 2018, and were 15-65 years old between 2004-2018. The median follow-up time was about eight years.
Throughout the study, 3300 people (7%) died. The most common cause of death was suicide—740 people died by suicide, 353 (48%) of them by overdosing on psychiatric drugs.
There were also 265 deaths listed as “accidental poisonings,” and 123 (46%) of those were overdoses of psychiatric drugs. It is unclear whether some or all of the deaths labeled “accidental poisonings” should instead have been considered “suicide,” considering the stigma that causes suicide to be labeled “accidents” in official records.
Alcohol-related causes were lumped together as the second most common cause of death (595 people), including alcohol-related liver disease as well as alcohol poisoning and alcohol dependence.
Another 552 people died of cardiovascular disease (CVD). Research has found that those taking antipsychotics are more than three times as likely to die of CVD, even after accounting for confounding factors; those taking a combined treatment of phenothiazine-type antipsychotics along with antidepressants found their risk of death from CVD increased by more than 18 times that of the general population.
The current researchers write, “Because of the observed high total number of deaths due to CVD, much of the recent research on mortality associated with BD has emphasized the importance of preventing CVD deaths. Therefore, the cardiometabolic tolerability of medicines for treating BD has also received increased attention among clinicians.”
Researchers have repeatedly found that people with diagnoses of major mental illness tend to die several decades earlier than the rest of the population. Though treatment rates have increased significantly over time, a recent study in the UK found that this “mortality gap” is also growing.
The current researchers suggest that psychiatry should focus on preventing substance use and suicide, although they don’t delve into any specifics of how that differs from current treatment goals.
“Targeting preventive interventions for substance abuse will likely reduce the mortality gap both due to external causes and somatic causes. Suicide prevention remains a priority, and better awareness of the risk of overdose and other poisonings is warranted.”
Paljärvi, T., Herttua, K., Taipale, H., Lähteenvuo, M., Tanskanen, A., Fazel, S., & Tiihonen, J. (2023). Cause-specific excess mortality after first diagnosis of bipolar disorder: population-based cohort study. BMJ Mental Health, 26(1), 1-7. http://dx.doi.org/10.1136/bmjment-2023-300700 (Link)