Warm Season Temperature-Mortality Relationships in Chisinau (Moldova)

Results of the epidemiological study of relationships between air temperature and daily mortality in Chisinau (Moldova) are presented. The research’s main task included description of mortality dependence on different temperature variables and identification of thermal optimum (minimal mortality temperature, MMT). Total daily deaths were used to characterize the mortality of urban and rural populations in April–September of 2000–2008, excluding the extremely warm season of 2007. The simple moving average procedure and 2nd-order polynomials were used for daily mean (Tmean), maximum (Tmax), and minimum (Tmin) temperatures and mortality approximation. Thermal optimum for mortality in Chisinau (15.2 deaths) was observed at Tmean, Tmax, and Tmin about 22°C, 27-28°C, and 17-18°C, respectively. Considering these values as certain cut-points, the correlations between temperature and mortality were estimated below and above MMTs. With air temperatures below its optimal value, each additional 1°C increase of Tmean (Tmax, Tmin) was accompanied by 1.40% (1.35%, 1.52%) decrease in daily mortality. The increase of Tmean and Tmax above optimal values was associated with ~2.8% and 3.5% increase of mortality; results for Tmin were not statistically significant. The dependency of mortality on apparent temperature was somewhat weaker below MMT; a significant relationship above MMT was not identified