Climate change represents a large-scale threat to mental health

A great deal of evidence supports the finding that environmental stressors produced by climate change have a negative impact on people's mental health.

Using weather data and sampling data from nearly 2 million US residents over a 10-year period, researchers found that warmer temperatures and increased precipitation worsened mental health.

"Recent research has shown that weather conditions can change daily mood and that warmer temperatures can increase the risk of suicide", Notch Obradovich, PhD, of the Massachusetts Institute of Technology and the Belfer Center for Science and International Affairs at Harvard University, stated Psychiatry Health. "Our study focuses on a common ground – the reported mental health problems – that until now has not been thoroughly examined in the empirical literature on the social impacts of climate change. "

The study, published in the Proceedings of the National Academy of Sciences, reported results of a large-scale quantification of mental health risks posed by climate change.

The investigators combined mental health data with meteorological data and empirical tools reported in the climate econometric literature to better understand the link between historical weather conditions and mental health. Researchers examined data from nearly 2 million US residents reported in the CDC's behavioral risk factor surveillance system between 2002 and 2012. Respondents answered how many days in the past month they had considered their mental health (stress, depression and emotional issues included) – not good. "

The results of pooled cross-sectional regression estimates revealed that increases in monthly temperature and additional precipitation increased the monthly risk of developing mental health problems.

"When our work is combined with previous work, it appears that warmer temperatures can worsen moods, increase the prevalence of mental health problems and magnify suicide rates, [which are] all the troubling results of their own right, "said Obradovich Psychiatry Health.

Mean temperatures above 30 degrees Celsius increased the risk of mental health problems by more than 1%, compared to 10 to 15 degrees Celsius (P <0.001), and months with more than 25 days of precipitation increased the risk by 2% over days without precipitation (P <0.001), depending on the results.

The investigators explained that switching from a monthly temperature of between 15 and 30 degrees Celsius at a temperature above 30 degrees Celsius over 30 days would generate nearly 2 million additional people reporting mental health problems when the patient was diagnosed with the disease. The magnitude of this link would be on a scale with the current American population. .

Low-income participants saw an increased risk of mental health problems if they were exposed to temperatures above 30 degrees Celsius (P = 0.002), which is 1.6 times the effect observed in high-income adults (P = 0.005). Women also found the greatest negative effect of rising temperatures on the risk of mental health problems (P = 0.005), or 1.6 times the observed effect in men (P = 0.031). Combining these results, the effect observed in a sub-sample of low-income women was about twice that observed for high-income men (P = 0.03).

"Ultimately, if the relationships observed in the recent past persist, the added climate change can magnify the burden of mental health at the societal level in the face of acute environmental threats generated by the warming of natural systems," wrote the authors. researchers in their study. "Given the vital role that good mental health plays in personal, social and economic well-being – and in the ability to meet pressing personal and social challenges – our results provide further evidence that climate change poses risks for human systems. " – by Savannah Demko

Disclosure: The authors do not report any relevant financial information.