Impact of Extreme Temperatures on Ambulance Dispatches Due to Cardiovascular Causes in North-West Spain

Abstract

Introduction and objectives. The increase in mortality and hospital admissions associated with high and low temperatures is well established. However, less is known about the influence of extreme ambient temperature conditions on cardiovascular ambulance dispatches. This study seeks to evaluate the effects of minimum and maximum daily temperatures on cardiovascular morbidity in the cities of Vigo and A Coruña in North-West Spain, using emergency medical calls during the period 2005–2017. Methods. For the purposes of analysis, we employed a quasi-Poisson time series regression model, within a distributed non-linear lag model by exposure variable and city. The relative risks of cold- and heat-related calls were estimated for each city and temperature model. Results. A total of 70,537 calls were evaluated, most of which were associated with low maximum and minimum temperatures on cold days in both cities. At maximum temperatures, significant cold-related effects were observed at lags of 3–6 days in Vigo and 5–11 days in A Coruña. At minimum temperatures, cold-related effects registered a similar pattern in both cities, with significant relative risks at lags of 4 to 12 days in A Coruña. Heat-related effects did not display a clearly significant pattern. Conclusions. An increase in cardiovascular morbidity is observed with moderately low temperatures without extremes being required to establish an effect. Public health prevention plans and warning systems should consider including moderate temperature range in the prevention of cardiovascular morbidity.

Effect of Temperature on Emergency Ambulance Call-Outs for Cardiovascular Causes: A Scoping Review

“…Onozuka and Hagihara (2015) 43 reported that 18.02% of emergency call-outs were attributable to non-optimal temperatures, with the majority of these (17.93%) being due to low non-optimal temperatures. Of this fraction, 16.92% were attributed to moderately low temperatures (between the 96th and 2.5th centiles), with only 19 in two cities in the northwest of Spain, with a significant effect of low temperatures observed in only one city (A Corunã).…”

“…The effect was assessed in seven studies. 16,18,19,21,22,43,45 Although none assessed it during cold waves, they did assess it at extremely low centiles. The effects due to low temperatures were studied over the course of the year in four studies 16,19,21,43 and during the cold season in three.…”

“…18,22,45 Generally, the effects were assessed by reference to the MMT, 18,19,21,43,45 and, in one case, 22 by reference to an arbitrary centile (25th centile). The centiles of comparison also varied, with low (<10th centile, 18 <5th centile, 18,19 <2.5th centile 21,43 ) or extreme (<1st centile 18,22,45 ) centiles being used. The effect was likewise assessed for each degree of decrease in the minimum morbidity temperature 16 and by calculating the attributable fraction to non-optimal temperatures.…”

“…16,18,19,21,22,28,35,40,43,44 Of these, six assessed the effect during the hot season, 18,22,28,35,40,44 while four papers investigated the effect throughout the year. 16,19,21,43 Most studies compared high centiles of temperature with a calculated MMT to assess the effects. 16,18,19,21,35,43,44 28 compared different climate conditions.…”

“…16,19,21,43 Most studies compared high centiles of temperature with a calculated MMT to assess the effects. 16,18,19,21,35,43,44 28 compared different climate conditions. The choice of comparison centiles varied across studies, with some using high centiles, such as >90th centile, 18 >95th centile, 18,19 and >97.5th centile 21,44 or even extreme high centiles, such as >99th centile.…”