# The correlational study of the 24 solar terms and meteorological factors with the acute exacerbation of bipolar disorder

## TL;DR

This study explores how the 24 solar terms and weather patterns relate to acute episodes of bipolar disorder in a Chinese population.

## Contribution

The study introduces the 24 solar terms as a novel framework to analyze seasonal patterns in bipolar disorder episodes.

## Key findings

- Manic episodes peak during Rainwater and Grain in Ear solar terms and correlate with temperature and wind speed differences.
- Depressive episodes peak during Rainwater and Summer Solstice and are linked to temperature and atmospheric pressure changes.
- Inter-day pressure and temperature differences are strong predictors of acute bipolar episodes.

## Abstract

Bipolar disorder (BD) is a severe mood disorder, and increasing evidence suggests that acute episodes of BD may exhibit seasonal patterns. However, the relationship between acute BD episodes and meteorological factors remains a contentious issue in academia. This study aims to investigate the distribution of BD acute episodes across 24 solar terms, offering a fresh perspective on the link between BD acute episodes and meteorological factors.

This analysis was based on retrospectively collected hospitalization records from patients with acute BD episodes at Anhui Mental Health Center (2020–2022), and contemporaneous meteorological data.

The two peaks of BD manic episodes occurred during Rainwater and Grain in Ear solar terms, whereas the peak of depressive episodes was observed during Rainwater and Summer Solstice solar terms. BD manic episodes were significantly correlated with temperature differences, interday temperature differences and interday wind speed differences. Depressive episodes were significantly correlated with the temperature difference, interday wind speed difference and atmospheric pressure. Linear regression analysis revealed that the interday atmospheric pressure difference and interday temperature difference were significantly associated with acute BD episodes.

This study conducted a large-scale survey on the distribution of acute BD episodes across 24 solar terms in the Chinese population and their correlations with meteorological factors and sociodemographic characteristics. The findings indicate that the distribution of BD acute episodes varies across the 24 solar terms and that there is a correlation between BD acute episodes and certain meteorological factors, particularly drastic changes in temperature and atmospheric pressure, which may account for the differences in the number of BD acute episodes across the solar terms.

•Significantly positively correlated with temperature differences and inter-day wind speed variations.•Atmospheric pressure shows a significant negative correlation with depressive episodes.•Inter-day pressure and temperature differences are positive predictors of acute episodes.•Marital status is significantly associated with episode distribution across solar terms.•Supports the development of personalized prevention strategies using meteorological and solar term characteristics.

Significantly positively correlated with temperature differences and inter-day wind speed variations.

Atmospheric pressure shows a significant negative correlation with depressive episodes.

Inter-day pressure and temperature differences are positive predictors of acute episodes.

Marital status is significantly associated with episode distribution across solar terms.

Supports the development of personalized prevention strategies using meteorological and solar term characteristics.