In order to assess the prevalence and associated factors for erectile dysfunction (ED) in primary care, a cross-sectional study was undertaken by questionnaire distributed to consecutive adult male attendees at 32 family practices. ED was assessed by the Korean five-item version of the International Index of Erectile Function (IIEF-5). In total, 3501 completed questionnaires were available for analysis. The prevalence of ED was severe (IIEF-5 score: 5-9) in 1.6% of cases, moderate (10-13) in 10.2%, mild (14-17) in 24.7%, and normal (18-25) in 63.4%. The prevalence of ED increased with age, lower educational status, heavy job-related physical activity, and lower income. ED prevalence was significantly higher in patients with chronic diseases such as diabetes, depression, and anxiety. These results suggest that the age-adjusted prevalence of ED among Korean men can be estimated as 32.2% (95% CI 30.6-33.7). Low socioeconomic status and several diseases such as diabetes, anxiety, and depression, as well as age, were associated with ED.

In order to investigate the safety and efficacy of sildenafil prescribed in primary care, a post-marketing surveillance study was undertaken. A total of 651 men with erectile dysfunction (ED) were enrolled from 31 family physicians in Korea from December 1999 to July 2002. Patients were regularly followed up to ascertain the safety and efficacy of sildenafil. Of the 651 patients enrolled, 572 (87.9%) returned for safety evaluation and efficacy assessment. In all, 458 (80.1%) of 572 patients reported improved erectile function with sildenafil. Hypertension, diabetes and low-dose sildenafil were associated with poor efficacy. A total of 71 adverse events were reported among 56 patients (8.6%), with the most frequent being hot flushes (5.6%), followed by headache (2.6%), palpitation (1.0%), anxiety (0.5%) and elevated ALT (0.5%). Only six patients (1.0%) discontinued sildenafil as a direct result of adverse events. These results suggest that sildenafil prescribed by primary care physicians was well tolerated and improved erectile function in patients with ED.