Risk of stroke among men with erectile dysfunction in Taiwan--patient-based or population-based?

摘要

I appreciated the work of Dr. Chung et al. in their article, "Increased risk of stroke among men with erectile dysfunction: a nationwide population-based study" [1]. Their study sheds light on the ability of physicians to educate male patients with erectile dysfunction (ED) older than 40 years in Taiwan [1,2]. I felt, however, that several points deserved further interpretation or discussion concerning their database.First, the people in the dataset analyzed were all patients (people with disease), and no healthy people were included. All the people entered into the dataset had at least one International Classification of Disease code assigned by the physicians. Furthermore, their "nationwide" study was from a very large patient pool, not really a population pool. When a population-based cohort study was performed, ED may not be an age-independent predictor of stroke for about 6 years [3],Second, less elderly patients suffered from ED than younger patients together with "seemingly low frequency of ED" [1] in the study. Dr. Chung et al. gave one reason: cultural taboo. However, the prevalence of ED in the study was quite different from other studies whose prevalence of ED was around 26% and increased with age in Taiwanese populations [2,4]. Because it was the patients, not the population, to be analyzed by the study authors, low frequency of ED was rational.