Impact of Environmental Temperature on Mortality in Severe Mental Illness Patients in Western China

Overview

This study analyzed the effects of ambient temperature on mortality among community-based patients with severe mental disorders (SMDs) in western China from 2006 to 2018. It found significant associations between both high and low temperatures, including extreme temperature events, and increased all-cause and cause-specific mortality in this vulnerable population.

Background

Premature death among patients with mental disorders is a major global public health concern, with over 6.4 million individuals affected by severe mental disorders (SMDs) in China alone. Patients with SMDs have mortality rates more than twice that of the general population, partly due to complications, behavioral factors, and impaired thermoregulation from psychotropic medications. Although ambient temperature is recognized as an important environmental factor influencing mortality, prior research has largely focused on outpatient visits or hospitalizations rather than death outcomes, and has not comprehensively assessed both high and low temperatures or extreme temperature events in community-managed SMD patients.

Data Highlights

Key Findings

• Both high and low ambient temperatures were significantly associated with increased all-cause mortality among community-based patients with SMDs.
• Extreme temperature events, including heat waves and cold spells, further elevated mortality risks in this population.
• The study uniquely assessed individual-level temperature exposure using a time-stratified case-crossover design, enhancing accuracy of exposure assessment.
• Cause-specific mortality analyses revealed temperature effects beyond all-cause mortality, highlighting vulnerable subgroups.
• Stratified analyses indicated that demographic factors such as age, gender, and economic status modified the temperature-mortality relationship.
• This is the first large-scale study to comprehensively evaluate temperature-related mortality risks in community-managed SMD patients in China.

Clinical Implications

Clinicians and public health authorities should recognize that patients with severe mental disorders are particularly vulnerable to temperature extremes, necessitating targeted interventions during heat waves and cold spells. Monitoring and support strategies should be intensified during high-risk seasons, especially for older adults and socioeconomically disadvantaged groups within this population. Integrating environmental risk awareness into mental health management plans may reduce premature mortality.

Conclusion

This pioneering study demonstrates that ambient temperature extremes significantly increase mortality risk among community-dwelling patients with severe mental disorders in western China. These findings underscore the need for tailored public health strategies to mitigate temperature-related mortality in this vulnerable group amid ongoing climate change.

References

1. Li Y et al. 2023 -- Impact of Environmental Temperature on Mortality Rates in Community-Dwelling Individuals with Severe Mental Illness