A Silent Threat: : Bipolar Disorder Revealed as a Pivotal Risk Factor for Early Death

By Lauren DeSouza- Master of Public Health, Simon Fraser Public Research University – Canada

Staff Research and Content Writer

Bipolar disorder (BD) is a severe mental illness that can cause both manic and depressed moods. It can also increase the risk of dying early (premature mortality).

Previous research has found that people with BD face a 10-15 year reduction in their lifespan. They also have 2-3 times the risk of premature mortality.

A new study from the University of Michigan has contextualized this risk of premature mortality. They compared the risk of early death from BD to other conditions and negative health behaviors that can shorten life.

In both their immediate cohort of people with BD and a larger sample of patients from Michigan Medicine, the researchers made a surprising finding: having BD was a much more significant risk factor for early death than cigarette smoking and other negative health behaviors.

Why are those with bipolar disorder more likely to die early?

The research community believes that there are two main reasons that people with bipolar disorder (BD) are more likely to die early. Firstly, co-morbid illnesses are common among those with BD. These include cardiovascular, metabolic, and respiratory diseases. Secondly, those with bipolar disorder may engage in more negative health behaviors than those in the general population. Negative health behaviors such as smoking, alcohol and other drug use, living a sedentary lifestyle, and poor eating habits contribute to the risk of early death.

As well, the psychotropic medications used to treat BD and other psychiatric illnesses have adverse side effects that contribute to chronic medical conditions such as diabetes and kidney disease. It is also important to note that those with severe mental illnesses such as BD often face inequitable access to medical care. This inequity can increase the risk of early death.

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What did this study do?

The goal of this study was to compare mortality rates in people with bipolar disorder (BD) with common causes of mortality, such as smoking and hypertension. This study was observational and used data from the Prechter Longitudinal Study of Bipolar Disorder (PLS-BD), one of the largest long-term cohorts of BD patients in the world. The Pretcher study has over 1128 participants, 847 of whom have BD, and follows them over time.

After analyzing data from the patients in the Pretcher study, the researchers validated their findings using a larger sample from Michigan Medicine. Michigan Medicine is the University of Michigan’s academic medical center. This larger sample has over 10,000 BD patients and 7000 control group patients without BD. This sample allowed the researchers to confirm that their results applied to patients in real-world conditions outside the Pretcher study.

What were the results?

This study found bipolar disorder (BD) to be a primary underlying cause of premature mortality (early death). 54 of 56 deaths that occurred in the Pretcher study population were in patients with BD. Having BD made someone 6 times more likely to die during a 10-year period compared to someone without BD. These findings were consistent among the larger Michigan Medicine cohort, with patients with BD being 4 times as likely to die early as patients without BD.

This risk of early mortality for BD was far greater than for smoking. This is significant because smoking is considered one of the leading causes of early death. Study participants who had ever smoked were more than twice as likely to die compared to those who did not smoke. Similarly, those with bipolar disorder of any age were more likely to die within 10 years than those who were 60 years of age or older. These findings did not change based on participants’ race or sex.

In this study, the early mortality rate for BD was higher than for any other medical condition except hypertension (high blood pressure). Hypertension was the only factor associated with an even higher chance of dying during the study period. Those who had hypertension were five times more likely to die than those with normal blood pressure, no matter whether they had bipolar disorder or not.

It is important to note that early death is exacerbated for people with severe mental illness due to the higher smoking rates. Up to 70% of people diagnosed with BD smoke. These individuals face an increased risk of early death from both smoking and BD. Having BD was also associated with several medical and physical comorbidities that also present a risk of premature death,

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including alcohol abuse, diabetes, and high blood pressure.

What is the significance of this study?

This study found that the risk of early death is higher for those with bipolar disorder (BD) than for conditions commonly seen as leading causes of death. Those with BD were more likely to die within 10 years than those who smoked or who were over 60 years old. This finding is significant because the public health community does not consider mental illness to be a leading cause of death. This is because mental illness is not an immediate cause of death but rather an underlying factor of conditions that lead to mortality. This study emphasizes the need to pay greater attention to mental illnesses such as BD as causes of early death.

Bipolar disorder is a significant risk factor for early death, with mortality rates outpacing other comorbidities listed as the leading causes of death (most of which are chronic diseases). However, unlike with smoking and high blood pressure, there has been little attention paid to preventing death from BD. The authors of this study argue that the focus on chronic disease prevention in public health has diverted attention away from preventing early mortality from mental illness. Mental illnesses such as BD represent a severe public health challenge. They significantly impact the health care system and cause high health and social costs. The authors conclude their paper with a call to action for policies, programs, and societal changes to improve the quality of life and life expectancy for those living with bipolar disorder.

What are the key takeaways?

People with bipolar disorder are 4-6 times more likely to die early than people without bipolar disorder.
Having bipolar disorder puts someone at a higher risk of early death than smoking or being over 60.
Bipolar disorder is not given the same attention as chronic conditions seen to be leading causes of early death.
More attention is needed to improve the quality of life and life expectancy for those living with bipolar disorder.

References

Anastasia K. Yocum, Emily Friedman, Holli S. Bertram, Peisong Han, Melvin G. McInnis. Comparative mortality risks in two independent bipolar cohorts. Psychiatry Research, 2023; 330: 115601 DOI: 10.1016/j.psychres.2023.115601