Severe varicose veins and the risk of mortality: a nationwide population-based cohort study

OBJECTIVE: Varicose veins (VVs) are common and although considered benign may cause morbidity. However, the association between VV severity and cardiovascular and mortality risks remains unknown. The aim of this study was to investigate the factors associated with overall mortality in patients with VV. METHODS: A total of 4644 patients with newly diagnosed VV between 1999 and 2013 were identified from Taiwan’s National Health Insurance Database. VV severity was classified from grade 1 to 3 according to the presentation of ulcers or inflammation. Moreover, 9497, 2541 and 5722 age-matched, sex-matched and chronic cardiovascular risk factor-matched controls, as assessed based on propensity score, were separately selected for three grading VV groups. Enrolled patients were analysed using conditional Cox proportional hazards regression analysis to estimate risk of mortality and major adverse cardiovascular events (MACEs) in the VV and control groups. RESULTS: Most patients with VV were free from systemic disease. However, compared with matched controls, patients with VV showed a 1.37 times increased risk of mortality (95% CI 1.19 to 1.57; p<0.0001). Compared with matched controls, older (age ≧65 years) (adjusted HR: 1.38; 95% CI 1.17 to 1.62; p=0.0001) and male patients with VV (adjusted HR 1.41; 95% CI 1.18 to 1.68; p=0.0001) showed increased risk of mortality. Furthermore, compared with controls, patients with VV showed 2.05 times greater risk of MACE. Compared with matched controls, population at grade 3 increased 1.83 times risk of mortality and 2.04 to 38.42 times risk of heart failure, acute coronary syndrome, ischaemic stroke and venous thromboembolism. CONCLUSIONS: This nationwide cohort study demonstrated that patients with VV are at a risk of cardiovascular events and mortality. Our findings suggest that presence of VV warrants close attention in terms of prognosis and treatment.