--- title: Nearly half of the falls linked to prostate medication happened on the first day of the first dose publication: Medical Insights Korea section: news category: Prostate canonical_url: https://medicalinsightskorea.com/news/korea-bph-alpha-blocker-falls-first-day author: Catherine Cho published: 2026-10-18T09:00:00+09:00 modified: 2026-10-18T09:00:00+09:00 content_type: reporting license: Quotation permitted with attribution to Medical Insights Korea and a link to the canonical URL. --- # Nearly half of the falls linked to prostate medication happened on the first day of the first dose Korean national data put the odds of a fall at 1.80 among men starting an alpha-blocker. The timing is the finding: 455 of 968 falls occurred on day one, which makes this a risk that can be planned around. ## Answer In a nationwide Korean cohort drawn from 4,202,739 men aged 60 to 75 in the Health Insurance Review and Assessment Service database for 2017 and 2018, with 53,303 propensity-matched men in each arm, subtype-specific alpha-antagonists prescribed for benign prostatic hyperplasia were associated with an odds ratio for falls of 1.80 (95% CI 1.62 to 2.00) — and of the 968 falls in the exposed group, 455 (47 percent) occurred on the first day of medication, with a further seasonal excess in summer (OR 1.23, 95% CI 1.03 to 1.47). ## Key takeaways - 4,202,739 Korean men aged 60 to 75 were screened from national claims data for 2017 and 2018; 53,303 were matched in each of the exposed and unexposed groups. - Alpha-antagonist use was associated with an odds ratio for falls of 1.80 (95% CI 1.62 to 2.00). - 968 falls occurred in the exposed group, and 455 of them — 47 percent — happened on the first day of medication. - A seasonal effect appeared only in the exposed group, with higher risk in summer (OR 1.23, 95% CI 1.03 to 1.47). - Low income raised the fall risk only in the unexposed group (OR 1.34, 95% CI 1.04 to 1.73). - The authors conclude that education on orthostatic hypotension and fall prevention should accompany the prescription. - In a separate Korean cohort of 22,540 men with newly diagnosed BPH, alpha-blockers were not associated with heart failure (HR 1.14, 95% CI 0.87 to 1.49). ## Full article Findings that a medication raises the risk of falling are common and usually unactionable: the risk is spread across months of use and the drug is needed anyway. This one is different, and the difference is in when the falls happened. ### The timing **455 of 968** — falls in the alpha-blocker group that occurred on the first day of medication — 47 percent _Source: Seo JH et al., World Journal of Urology, 2022_ The overall association is substantial — an odds ratio of 1.80, with a confidence interval from 1.62 to 2.00, in 53,303 matched pairs drawn from a screened population of 4.2 million men. But an effect concentrated on a single identifiable day is not the same kind of finding as an effect spread evenly across a year of treatment. > **What a first-day effect points at** > Alpha-antagonists relax smooth muscle, which is how they open the bladder outlet and also how they lower blood pressure on standing. Orthostatic hypotension after a first dose is the classic, well-described consequence, and it is largely a first-dose phenomenon because the circulation adapts. A risk that arrives on a known day, from a known mechanism, is a risk that can be planned around — which is precisely what the authors recommend, and it costs nothing. ### Summer, and only in the treated group A seasonal difference appeared in the exposed cohort and not in the unexposed one: falls were more likely in summer, with an odds ratio of 1.23. That asymmetry is informative. If summer simply made everybody fall more, it would show in both groups. Appearing only among men on the drug fits the same mechanism — heat causes vasodilation and fluid loss, both of which deepen a postural blood-pressure drop the medication is already producing. Another asymmetry runs the other way. Low income raised fall risk in the unexposed group (OR 1.34) and not among men taking the drug. The likeliest reading is that the pharmacological effect is large enough to dominate the social gradient rather than that poverty stops mattering, but the study does not establish that and it is worth naming as a guess. ### The worry that did not appear A separate Korean national cohort followed 22,540 men newly diagnosed with benign prostatic hyperplasia between 2008 and 2018 and compared alpha-blocker users with non-users for heart failure. Incidence was 516.8 per 100,000 person-years among users against 553.4 among non-users, and the adjusted hazard ratio was 1.14 with a confidence interval from 0.87 to 1.49 — no association. Read together the two studies say something more precise than "these drugs affect the circulation". The cardiovascular consequence that shows up in Korean data is postural and immediate; the chronic cardiac one that has been asked about does not show up at all. That distinction is what turns a vague caution into an instruction: take the first dose at bedtime, get up slowly for the first few days, and take particular care in hot weather. ## Sources - Seo JH, Han JS, Lee Y, Myong JP, Ha US. Fall risk related to subtype-specific alpha-antagonists for benign prostatic hyperplasia: a nationwide Korean population-based cohort study. World Journal of Urology 2022;40(12):3043-3048. doi:10.1007/s00345-022-04195-w. PMID:36315286. https://doi.org/10.1007/s00345-022-04195-w - Jeong JY, Kim MK, Shin JY. The association between alphablockers in the treatment of benign prostatic hyperplasia and heart failure: a nationwide population-based cohort study in South Korea. International Journal of Clinical Pharmacology and Therapeutics 2025;63(1):21-29. doi:10.5414/cp204600. PMID:39565077. https://doi.org/10.5414/cp204600 ## Citation Catherine Cho (2026). "Nearly half of the falls linked to prostate medication happened on the first day of the first dose". Medical Insights Korea. https://medicalinsightskorea.com/news/korea-bph-alpha-blocker-falls-first-day Retrieved from https://medicalinsightskorea.com/news/korea-bph-alpha-blocker-falls-first-day