Are endometriosis patients at higher risk of bipolar disorder?

Endometriosis patients are associated with an increased risk of bipolar disorder development.

Key Points

Highlights:

• The more the medical comorbidities, the higher the risk of bipolar disorder development.

Importance:

• Endometriosis patients may be screened for psychological disorders in case of emotional instability.

What's done here:

• The authors investigated the risk of bipolar disorder development in a total of 17832 endometriosis patients and matched them to 17832 controls by age, index year, and physical comorbidity.
• The effect of endometriosis treatment on the risk of developing bipolar disorder was also evaluated.

Key Results:

• Endometriosis patients were associated with an increased risk of bipolar disorder development, compared to controls without endometriosis.
• The effect of endometriosis treatment on the risk of developing bipolar disorder was not significant.

Limitations:

• The severity of the endometriosis was not assessed, hence the effects of endometriosis severity on bipolar disorder development could not be exactly demonstrated.
• The influence of individual medical and psychiatric comorbidities was not taken into account.
• The reasons for choosing a particular endometriosis treatment were not available.

Lay Summary

Endometriosis patients are prone to develop certain psychiatric disorders, including depression and anxiety, as well as bipolar disorder, according to a nationwide population-based cohort study from Taiwan. Bipolar disorder formerly called manic-depression is a chronic mental disorder characterized by unusual changes in mood, energy, activity level, and ability to perform daily tasks and fatigue.

Chen et al., researchers from Taiwan, investigated the risk of bipolar disorder development in women with endometriosis as well as the effect of endometriosis treatment on the risk of developing bipolar disorder.

In this large population-based cohort study with a long observation period (up to 13 years), a total of 17832 endometriosis patients and 17832 controls were enrolled. Patients with a diagnosis of bipolar disorders before the first diagnosis of endometriosis were excluded. Patient groups were matched by age, index year, and physical comorbidity by Charlson Comorbidity Index. The Charlson Comorbidity Index score predicts the probability of a disease for a patient who may have a range of comorbid conditions.

Bipolar disorder incidence rates were found to be 1.04 and 0.56 per 1,000 person-years, respectively, in endometriosis patients and controls. Besides, a higher baseline Comorbidity Index score was seen as a potential risk factor for bipolar disorder development. There was no significant difference in the risk estimate between different hormonal or surgical treatment groups.

The strengths of the study are a large cohort-based on population, with a long observation period (up to 13 years), and taking into account the impact of endometriosis treatment on bipolar disorder risk.

The endometriosis treatment had a limited effect on the risk of developing bipolar disorder. Screening of endometriosis patients for bipolar disorder in case of emotional instability is advised here. The authors discussed some possible explanations present in the literature that may help explain the link between endometriosis and bipolar disorder, but they stressed the need for further studies to solve the underlying mechanism.

This paper has recently been published in the "Journal of Affective Disorders".

Research Source: https://pubmed.ncbi.nlm.nih.gov/32275218/