TOPLINE:

Extreme nighttime heat was linked to a significantly increased prevalence of suicidal help-seeking behavior in a new study, with a 19% increase at the 90th percentile of temperatures and a 166% increase at the hottest 99th percentile.

METHODOLOGY:

• Researchers analyzed nearly 11,700 suicide risk assessments conducted using data from hotline calls, chats, or texts from Louisiana residents (53% aged 25 years or older; 56% women; 52% White) between 2019 and 2023.
• Nighttime minimum temperature percentiles were used to define hot days (≥ 90th percentile) and cold days (≤ 10th percentile).
• Natural language processing was applied to counselor notes to identify contexts of help-seeking crises, including sleep issues, mental health issues, isolation, substance use, exposure to interpersonal stressors, and unmet basic needs.

TAKEAWAY:

• Suicide-related help-seeking behavior increased by 19%-166% as nighttime temperatures rose, with prevalence ratios (PRs) of 1.19 at the 90th percentile, 1.55 at the 95th percentile, and 2.66 at the 99th percentile. On the other hand, the prevalence decreased with decreasing temperatures, with PRs of 0.67 for the 10th percentile, 0.55 for the fifth percentile, and 0.40 for the coldest first percentile.
• At the 99th percentile of temperature, there was a marked increase in calls related to sleep issues (by 146%), an expressed intent to die (163%), availability of lethal means (145%), and having few future plans (224%).
• Calls about mental health crises and unmet basic needs increased by 21% and 60%, respectively, at the 90th percentile of temperature; whereas sleep-related help-seeking decreased with colder temperatures (by 32% at the 10th percentile).
• At high temperatures, mental health concerns increased for youth, women, and Black individuals, while Black individuals and men reported increased substance use.

IN PRACTICE:

These results “inform proactive interventions, such as temperature-triggered staffing protocols and integration of basic needs support into suicide prevention during extreme weather events,” the investigators wrote.

SOURCE:

The study was led by Sophia C. Ryan, University of North Carolina at Chapel Hill. It was published online on February 11 in PLOS Mental Health.

LIMITATIONS:

Missing demographic information from 35%-79% of calls may have introduced a selection bias, and the overrepresentation of youth, women, and Black individuals in the sample compared with the general Louisiana population may have influenced the findings. Additionally, the findings may not be generalizable beyond Louisiana's specific climate and demographic context. 

DISCLOSURES:

The study was funded by the National Academy of Sciences Gulf Research Program. The investigators reported having no relevant conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.