Physiological equivalent temperature and hospitalized due to respiratory and cardiovascular diseases in Dezful, Iran

The Physiological Equivalent Temperature (PET) index providing a standardized reference point, PET enables non-experts to better understand and assess the physiological implications of varying environmental temperatures and thermal comfort levels across different settings. We aimed to evaluate the relationships between the PET Index and Hospitalized due to Respiratory Diseases (RD) and Cardiovascular Diseases (CVD) in Dezful city.

Hospital admissions, climate variables and environmental pollution data (PM_2.5, PM₁₀) of Dezful city were collected from 2014 to 2019. The relationships were assessed using Distributed Lag Non-linear Models (DLNM) in conjunction with quasi-Poisson regression methods. The effect of Confounding variables was adjusted.

In high PET, the risk of respiratory diseases has been significantly reduced (Lag _0-7 and Lag _0-14). Additionally, in the group of females and individuals <65 years old admitted to the hospital, the risk of respiratory admissions, as well as the risk of cardiovascular admissions among females, has also been significantly reduced. Additionally, in low PET, the risk of cardiovascular disease hospitalization (especially in male) increased significantly (Lag_0-14).

It seems that in Dezful, low levels of PET increase the risk of hospitalization for cardiovascular patients, while due to certain factors, including the potential adaptive effect of the people of Dezful to heat on health, high levels of PET reduce the risk of hospitalization for all respiratory diseases and the risk of cardiovascular hospitalization in women.