The potential of cardiovascular risk factors for reducing visual impairment: a pooled analysis of European epidemiological studies

Purpose: to estimate the proportion of visual impairment (VI) that could potentially be avoided if the population wasnot exposed to cardiovascular risk factors.Methods: The European Eye Epidemiology (E3) consortium is a collaborative network of epidemiological studies.Fourteen cross-sectional population-based studies from 9 European countries were included in a pooled analysis ofindividual participant data. VI was defined as best-corrected visual acuity < 20/60 at better eye. Cardiovascular riskfactors included smoking, diabetes, hypertension, obesity and overweight, hyperlipidemia and history ofcardiovascular disease. Multivariate mixed logistic regression models, using a random effect for studies, were used toestimate the odds-ratios of the associations of cardiovascular risk factors with VI. The proportions (95% CI) of VI dueto the risk factors were estimated using population attributable fractions (PAF). PAF were calculated for statisticallysignificant risk factors from the odds-ratios and the prevalence of the risk factors in subjects with VI, and theirconfidence intervals (CI) were estimated by bootstrapping.Results: 55,467 subjects, aged 45 years or more, were included in the analysis. In the multivariate analysis includingall risk factors, higher risk of VI was significantly associated with age (p<0.0001), female gender (p=0.02), smoking(p=0.0002), diabetes (p=0.001) and cardiovascular disease (p<0.0001), while decreased risk of VI was significantlyassociated with secondary and higher education (p=0.0002), and overweight and obesity (p=0.01). No statisticallysignificant associations were found with hypertension and hyperlipidemia. PAF was 4.8% (95% CI: 2.7-6.8) for currentsmoking, 4.6% (95% CI: 2.9-6.4) for diabetes, 6.2% (95% CI: 3.5-8.8) for cardiovascular disease and 12.9% (95% CI:9.5-16.5) for any of these 3 risk factors. PAF for cardiovascular risk factors were higher for men (23.7% for any riskfactor, 95% CI: 16.7-31.0) than for women (9.3%, 95% CI: 5.2-12.7).Conclusions: our study shows that VI might be reduced by more than 10% if cardiovascular risk factors could beavoided, with a greater effect in men (23.7%) than in women (9.3%).(No Image Selected)Layman Abstract (optional): Provide a 50-200 word description of your work that non-scientists can understand.Describe the big picture and the implications of your findings, not the study itself and the associated details.:According to this study, which groups data from 14 European epidemiological studies and more than 55,000participants, visual impairment might be reduced by more than 10% if cardiovascular risk factors could be avoided,with a greater effect in men (almost 25%) than in women (9%).