Gender differences in the influence of physical activity and non-smoking on risk of heart failure in a general population. A meta-analysis and systematic review

Abstract

<p>Background and Introduction: Heart failure (HF) is a serious disease, which shows poor prognoses and high morbidity in both genders. This results in enormous challenges for caregivers, researchers, and policy makers in addition to suffering of affected person and his or her family. There is some controversy regarding the association between life style factors and the incidence of HF in men and women. The relationship between physical activity and smoking and risk of HF has mostly been reported irrespective of gender; however, similar doses of physical activity and smoking cessation may contribute differently to protection against HF in men and women. In the present thesis, a systematic review and a meta-analysis were carried out to investigate the influence of gender on association between smoking and physical activity with the incidence of HF. <p>Methods: The meta-analysis and systematic review are based on literature identified by search in the MEDLINE, EMBASE and CINHAL databases up to February the 1st, 2019. Risk ratios (RR) and hazard ratios (HR) estimate from observational studies were pooled in a random effect meta-analysis. <p>Findings: 2413 articles’ abstracts were reviewed and identified 9 population cohort studies (more than 3 million participants, 52.6% women), that adjusted for common cardiovascular risk factors. For analyses of the effect of smoking on HF, a total of 8 population cohort studies involving 2,986,217 participants (48.55% women) with a mean range of follow-up time of 5.5 to 19 years, with 68,983 cases of HF (2.31% of all participants developed HF, and 48.0% of HF cases were women) were included. The risk of HF among smokers was higher than in non-smokers, with higher risks in women than in men. In women, pooled HR was 1.83; 95% CI, (1.62, 2.05), <i>I</i>²=0.0% (p= 0.72), and for men pooled HR was 1.58; 95% CI (1.41, 1.75), <i>I</i>²= 38.6% (p= 0.180). For analyses of the effect of physical activity, a total of 6 cohort studies involving 1,105,467 participants (47.0% women) with the range of mean follow-up time of 5.8 to 19 years, with 60,158 cases of HF (5.44% of all participants developed HF) were included. According to estimated effect sizes in the included studies, engaging in high levels of physical activity was associated with a significant reduction of HF incidence in both men and women. The effect of high levels of physical activity on the risk reduction of incident HF was stronger in women than in men. In women, pooled HR was 0.69; 95% CI, (0.61, 0.76), <i>I</i>²=0.0% (p= 0.676), and for men pooled HR was 0.73; 95% CI (0.66, 0.81), <i>I</i>²= 70.9% (p= 0.0.32). <p>Interpretation: Smoking and physical inactivity increased the risk of HF. Risk increase was for both stronger in women than in men. It is not clear whether the different risk of HF among men and women is biological or related to the patterns of behaviors. However, policies addressing smoking and physical inactivity should consider gender specific adaptations particularly in those countries where women are less physically active than men, while at the same time smoking prevalence is increasing among young women.