Association between ambient temperature and emergency psychiatric consultations: A case-crossover study in a South American emergency setting (2021–2023)

Background: Although environmental factors have been studied for their impact on mental health, the link between ambient temperature and mental disorders remains insufficiently explored. Aim: This study aimed to explore the relationship between ambient temperature and the frequency of emergency psychiatric consultations at the sole university hospital in Paraguay from 2021 to 2023. Methods: This investigation adopted a quantitative, observational, cross-sectional design, using a case-crossover approach. Data collection entailed reviewing patient records and meteorological data, focusing on the daily mean temperatures and other meteorological variables. Statistical analysis was conducted using RStudio and SPSS, applying a distributed lag non-linear model (DLNM) for a seven-day lag period. Multinomial logistic regression was used to estimate odds ratios (ORs) for the likelihood of specific diagnoses resulting in emergency consultations in relation to temperature exposure. Results: The analysis covered 2,186 first-time emergency psychiatric consultations, with anxiety disorders being the most frequent diagnosis (24.3%), followed by depressive disorders (23.4%) and personality disorders (15.8%). Women accounted for 70.6% of all patients. The findings indicated that higher temperatures were associated with a greater frequency of consultations for certain disorders, including bipolar (OR up to 27.12 at Lag 1) and eating disorders (OR up to 100 at Lag 1). Conversely, a negative association was observed for schizophrenia, dissociative disorders, and trauma- and stressor-related disorders as temperature increased. Additionally, a linear relationship was found between lower relative humidity and increased number of consultations. Conclusions: The findings underscore the impact of ambient temperature on psychiatric emergency consultations, revealing that the frequency of consultations for different conditions varies with temperature. These insights could inform public health strategies to mitigate the effects of climatic variation on mental health. These findings suggest the need for targeted mental health interventions to address vulnerabilities during periods of climatic stress, particularly in resource-limited settings.