No, this is not happening in Italy now, but it is evidence that we should seriously think about it in the coming years. The results of an extensive review of recent literature on the relationship between the two were published in the medical journal The Lancet. fever and mental health. A connection that has backfired: Over the years, articles have appeared that highlight the correlation between high ambient temperatures and poorer mental health in a certain population (net of other elements that could influence this trend), while others have not found an equally obvious connection.
Here instead For the first time, both quantitative and qualitative synthesis of the literature was carried out, which took into account a wide range of mental health indicators., including self-reported well-being. The result: There was a direct link between increases in absolute, relative and extreme temperatures and a range of mental health outcomes, including suicide and hospitalizations for mental illness.
260 articles were assessed, divided into three groups: correlations with suicide rates.; with the frequency of hospitalizations for mental illness; and articles on mental health and community well-being. Considering the wide range of definitions and variables relating to “heat”, absolute temperatures (e.g. mean, minimum or maximum), temperature variability, which refers to quantitative measures of relative temperature (e.g. inter-day or intra-day variation, and deviation from the mean); but also heat waves and the frequency of temperatures considered extreme.
The association between suicide and temperature was assessed in three meta-analyses (i.e., cluster analyses).. One looked at suicide rates as a function of average monthly temperature, finding a 1.5% increase in incidence for every 1 degree Celsius increase in temperature. A second meta-analysis of suicide rates in relation to average daily temperature showed a 1.7% increase in incidence for every 1°C increase in temperature. The third meta-analysis looked at the risk of suicide for every 1°C increase in average monthly temperature, finding an increase in suicide risk of 1.01%.
Regarding hospitalizations, a meta-analysis shows that A heat wave, defined as a maximum daily temperature of at least 35°C for at least 3 consecutive days, was associated with a 9.7% increase in hospital visits or hospitalizations for mental illness compared to periods without heat waves..
A third group of studies assessed ambient temperature and the mental health and well-being of the population. The majority of studies (68%) assessed mental health and perceived well-being through surveys of mood, general perceived well-being, psychological distress, and depressive symptoms. Some of these studies reported a significant association between at least one temperature measure and at least one measure of mental health or well-being. 14 studies (74%) found that higher temperatures were generally associated with worse outcomes. One study found improved well-being scores during “hours of comfortable weather” in the summer, while another found improved mood during time spent outdoors in the spring (in “pleasant” temperatures) but worsened during time spent outdoors in the summer.
How to interpret this data?
Of course, not as definitive numbers, given the extreme heterogeneity of results depending on the method used, the indicators chosen and the definition of terms such as “heat waves”. For example, two studies assessed rates of psychiatric hospitalization as a function of average daily temperature. Of these, one reported a strong and significant linear relationship, while the other reported no interesting relationship.
The fact remains that even if it is not possible to accurately estimate the impact of rising temperatures on mental health, a link between the two emerges from many of the studies reviewed.
All studies for temperature change, 90% for heat waves and 90% for absolute temperature showed a significant positive association between higher temperatures and hospital visits or hospitalizations for mental health problems. 60% of them assessed any mental disorder, and the remaining 40% looked at specific conditions or behaviors.