Association of benign prostatic hyperplasia and subsequent risk of bladder cancer: an Asian population cohort study
Few studies discussed the link between benign prostatic hyperplasia (BPH) and bladder cancer. We performed this cohort study to investigate whether there is an association between BPH and subsequent risk of bladder cancer.
We identified 35,092 study subjects including 17546 BPH patients and 17546 comparisons from the National Health Insurance database. The comparison cohort was frequency matched with age and index-year. We measured subsequent bladder cancer rates (per 1000 person-years) in two cohorts. Attributable risks (ARs) was calculated based on the bladder cancer rates in two cohorts. The hazard ratios (HRs) and 95% confidence intervals (CIs) for bladder cancer were estimated via Cox proportional hazard regression.
BPH patients had a higher bladder cancer rate than comparisons (AR = 0.81 per 1000 person-years) and exhibited 4.69- and 4.11-fold increases in bladder cancer risk in the crude and adjusted Cox models, respectively (95% CIs = 4.15–6.99 and 2.70–6.26). The AR was highest in patients aged 65–74 years old (AR = 1.33). BPH patients with chronic kidney disease were at an elevated bladder cancer risk. Regarding the association between bladder cancer and transurethral prostatectomy (TURP), BPH patients who underwent TURP were at a higher risk of bladder cancer (AR = 1.69; HR = 6.17, 95% CI = 3.68–10.3) than those who did not (AR = 0.69; HR = 3.73, 95% CI = 2.43–5.74).
In this study, BPH patients were found to have an increased risk of subsequent bladder cancer. Based on the limitations of retrospective nature, further studies are needed.
KeywordsBenign prostatic hyperplasia BPH Bladder cancer
This study is supported in part by Taiwan Ministry of Health and Welfare Clinical Trial Center (MOHW106-TDU-B-212-113004), China Medical University. Hospital, Academia Sinica Taiwan Biobank Stroke Biosignature Project (BM10601010036), Taiwan Clinical Trial Consortium for Stroke (MOST 106-2321-B-039-005), Tseng-Lien Lin Foundation, Taichung, Taiwan, Taiwan Brain Disease Foundation, Taipei, Taiwan, and Katsuzo and Kiyo AoshimaMemorial Funds, Japan.
CWF conceived and designed the study as well as wrote the initial draft of the manuscript. CHL participated in the study design and conception. CHM performed data analysis and interpretation and was involved in writing the initial draft of the manuscript. SCW designed the study, performed data analysis and interpretation and was involved in manuscript drafting and revision. Guarantor of the article: Wu SC, MD.
Compliance with ethical standards
Conflict of interest
This study used the National Health Insurance Research Database established by the National Health Research Institutes with the authorization of the Bureau of National Health Insurance of the Department of Health of Taiwan. The interpretations and conclusions contained herein do not represent the opinions of the aforementioned agencies and institutions. The authors declare that there are no conflicts of interest related to this study.
Research involving human participants and/or animals
To comply with the Personal Information Protection Act, all of the identifying information of the insured people were removed and replaced with surrogate numbers for research use. This study was approved by the Research Ethics Committee of China Medical University and Hospital in Taiwan [CMUH104-REC2-115(CR-1)].