Seasonal variation in the frequency of venous thromboembolism: An updated result of a meta-analysis and systemic review

Abstract

Objective Venous thromboembolism, including deep vein thrombosis and pulmonary embolism, is likely to cause the death of both medical and surgical patients. Despite some evidence of seasonal variation in the incidence of venous thromboembolism, the existing studies obtain contradictory results. A temporal pattern for pulmonary embolism is known, but data on deep vein thrombosis are inconclusive. The purpose of this study is to make a meta-analysis and systematically review the literature about seasonal variations of pulmonary embolism and/or deep vein thrombosis in order to objectively diagnose venous thromboembolism. Methods According to dichotomous data, risk ratios (RRs) and 95% confidence intervals (CIs) were used to compare the incidence of venous thromboembolism in different seasons. The research was classified according to pulmonary embolism mortality, pulmonary embolism/deep vein thrombosis incidence, latitude/elevation/climatic types, and monthly incidence for four subgroup comparisons. There were a total of 23 eligible studies, in which 40,309 patients with venous thromboembolism were compared. Results The pooled total venous thromboembolism incidence was 27.2% in winter, 23.1% in spring, 24.6% in summer, and 25.1% in autumn. According to the results of pooled analysis, the incidence of venous thromboembolism in winter was much higher than that in summer (RR = 1.12, 95% CI: 1.01–1.24, adjusted P = .04), especially deep vein thrombosis. Moreover, the incidence of venous thromboembolism in summer and autumn was lower than that in winter in low-latitude (<200 m) areas and median low-latitude (0–50°-N) areas. Interestingly, the frequency of pulmonary embolism mortality was the largest in spring and smallest in summer (spring > winter ≈ autumn > summer). For monthly data, a statistically significantly lower incidence of venous thromboembolism was observed in May and July than in October. Conclusions The study revealed a significantly higher incidence of venous thromboembolism and deep vein thrombosis in winter than in summer. Pulmonary embolism mortality occurred more frequently in spring than during other seasons. A statistically significantly lower incidence of venous thromboembolism was observed in May and July compared with that in October.

Seasonal variation in in-hospital outcomes of Takotsubo-syndrome-related admissions: A National Inpatient Analysis, 2019

“…When compared to summer, there was a greater incidence of AF in winter (OR:1.22; 95% CI:1.02–1.45) [ 4 ], spring (OR:1.20; 95% CI:1.02–1.42), and fall (OR:1.28; 95% CI:1.08–1.51). Spring admissions had a greater risk of VTE than summer admissions [(OR:1.54; 95% CI:1.09–2.16) vs. summer; p = 0.067] which is what was reported by Zhao H et al [ 6 ]. Other outcomes, such as all-cause mortality and cardiogenic shock, were not associated after controlling for confounding variables.…”

Risk of Venous Thromboembolism With Gout Flares

“…Incidence rate ratios (IRRs) with 95% confidence intervals (95% CIs) were calculated for each stratum of the exposed period compared with the baseline period (12). We adjusted for season and age (2-year age bands) to account for the seasonal trend of gout flares and VTE (21,22), and increasing incidence of gout flares and VTE with age (23,24). Supplementary Material S2 shows the sample size estimation (available on the Arthritis & Rheumatology website at https://onlinelibrary.wiley.com/doi/ 10.1002/art.42480).…”

Seasonal dynamics of myocardial infarctions in regions with different types of a climate: a meta-analysis

“…There is an observation that hypobaric exposure activates coagulation [71]. However, based on the results of publications [72][73][74][75] included in the meta-analysis Zhao et al [76], investigating the seasonal dynamics of thromboembolism, it can be concluded that in regions with low atmospheric pressure in summer (China, Korea), thromboembolism occurs more often in winter than in summer. It was shown that in addition to cholesterol and hematocrit, levels of blood coagulation factors increase in winter compared to summer [77][78][79].…”