Diurnal temperature range and hospital admission due to cardiovascular diseases: A systematic review and meta-analysis study

This study investigated the impact of the diurnal temperature range (DTR) on hospitalizations related to cardiovascular disease (CVD). Following the PRISMA protocol, a systematic review and meta-analysis searched various databases for English studies using keywords related to DTR and CVD up to June 1, 2023. A random-effects meta-analysis model was utilized to aggregate previous estimates of DTR effects on CVD admissions. The findings revealed that a 1 °C increase in DTR is associated with a 1.5 % increase in all CVD hospitalizations (95 % CI: 0.2 %, 3 %). Additionally, for each 1 °C increase in DTR, admissions due to acute myocardial infarction (AMI) and heart failure increased by relative risks (RR) of 1.02 (95 % CI: 1.01, 1.03) and 1.04 (95 % CI: 1.03, 1.04), respectively. Our analysis showed that a 1 °C increase in DTR was associated with a 0.9 % increase in all CVD hospital admissions among those aged ≥65 years (95 % CI: 0.3 %, 1.6 %). The overall estimates indicated that DTR (per 1 °C increment) was associated with a 0.6 % (95 % CI: 0.2 %, 1.1 %) increase in females and a 1.7 % (95 % CI: 1.3 %, 2.2 %) increase in males. It was statistically significant for elderly individuals, corresponding to a 4.5 % increase in stroke risk (RR: 1.045 [95 % CI: 1.01, 1.07]). Overall, this study emphasizes that daily fluctuations in DTR increase the hospitalization risk in cardiovascular patients, highlighting the need to consider the effects of DTR on cardiovascular health, especially among vulnerable age and sex groups.