Wind and coronary artery disease

Meteorological parameters, such as atmospheric temperature, pressure, relative humidity, wind velocity, and so on, may play an important role in cardiovascular diseases. Cold exposure is associated with cardiovascular hospitalization, and lower temperature is related to cardiovascular mortality and intracerebral hemorrhage. Lower temperature is also associated with myocardial infarction (MI). Furthermore, lower maximal humidity and higher minimal humidity are suggested to be related to hospitalization for angina. The association of wind velocity with coronary artery disease (CAD), however, has been less investigated, and no meta-analysis of this has been conducted to date. In the present article, to determine whether wind velocity is related to CAD, we performed the first meta-analysis of contemporary meteorological studies. The present meta-analysis was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) (http://www.prisma-statement.org). All studies investigating the meteorology of CAD were identified using the following two-level search strategy. First, PubMed, Web of Science, and Google Scholar were searched up to August 2019. Studies investigating the association of wind velocity with CAD were included. The outcome of interest was CAD, especially acute coronary syndrome (ACS), including acute MI and unstable angina. The quality of the studies was evaluated using the Risk of Bias Assessment Tool for Nonrandomized Studies (RoBANS), and risk of bias was evaluated as low, high, and unclear in accordance with six components. Adjusted (unadjusted if unavailable) relative risks (RRs) with their confidence intervals (CIs) for CAD per unit increment of wind velocity were extracted from each study. Data were extracted by two investigators (HT and TK) in duplicate and independently ascertained by a third researcher (TA), and disagreements were solved by consensus. Study-specific estimates were combined using a random-effects model. Between-study heterogeneity was assessed by the I statistic, and values on the order of 25%, 50%, and 75% were considered as low, moderate, and high heterogeneity, respectively. Funnel plot symmetry (suggesting publication bias) was mathematically estimated by Egger’s linear regression test. To visually evaluate inconsistency, heterogeneity, distribution, and publication bias for RRs, the radial (Galbraith) and normal quantile-quantile (Q-Q) plots were generated in the random-effects model. Sensitivity analyses were conducted to examine the contribution of each study to the pooled estimate by eliminating individual studies one at a time and recombining RRs for the remaining studies. All analyses were performed using Review Manager version 5.3 (http://tech.cochrane.org/revman) and JASP version 0.10. 2 (https://jasp-stats.org). As illustrated in Supplementary Figure S1, nine eligible studies were identified (Table 1). The quality (risk of bias) of the studies is shown in Supplementary Figures S2 and S3. The outcome was CAD death in one study, acute MI in four studies, and ACS (including acute MI and unstable angina) in four studies. Daily mean wind velocity was used for the analysis in all but one (analyzing wind velocity measured at 18 p.m.) study (Table 2). Some RRs per non-1-m/s increment in wind velocity were converted into those per 1-m/s increment using the standard formula. The primary meta-analysis demonstrated a relation of higher wind velocity to a statistically significant increase in CAD risk (RR per 1-m/s increment, 1.0217; 95% CI, 1.0060 to 1.0375; p1⁄4 0.006; I1⁄4 80%; Figure 1). Funnel plot asymmetry was not identified (p1⁄4 0.204; Supplementary Figure S4, upper