Increased risk for cancer following erectile dysfunction: A nationwide population-based follow-up study

Introduction. Previous studies have suggested that erectile dysfunction (ED) is associated with chronic inflammation, which is also a principle mechanism of carcinogensis. However, very few studies have attempted to examine the association between ED and subsequent cancer. Aim. Using a nationwide population-based data set, the aim of this study is to investigate the risk for cancer during a 5-year follow-up period after a diagnosis of ED, compared to patients without ED during the same period, while adjusting for socio-demographic characteristics. Main Outcome Measure. Stratified Cox proportional hazard regression was performed to compare the 5-year cancer-free survival rate for the two cohorts. Methods. This study used data sourced from the Taiwan "Longitudinal Health Insurance Database." The study cohort comprised 1,882 patients with ED and 9,410 randomly selected subjects as the comparison cohort. Each patient was then individually tracked for 5 years from their index ambulatory care visit to identify those who had diagnosed episodes of cancer. Results. Of the sampled patients, 183 (1.6%) had cancer within the 5-year follow-up period, that is, 43 individuals (2.3% of the patients with ED) from the study cohort and 140 individuals (1.6% of patients in the comparison cohort) from the comparison cohort. After adjusting for the patients' monthly income, the geographic location and urbanization level of the community in which the patient resided, hypertension, diabetes, coronary heart disease, and hyperlipidemia, regression analysis reveals that the hazard of having cancer during the 5-year follow-up period was 1.42 (95% CI=1.03-2.09, P=0.039) times greater for patients with ED than comparison patients. However, data on smoking, which is an important factor in ED and cancer, is not available and remains a potential confounder. Conclusions. We conclude that the incidence of cancer in the 5 years after an ED diagnosis is significantly higher than in the general population.