6 Background: Study compliance is crucial when the study outcome is determined by an invasive procedure, such as prostate biopsy. To investigate predictors of compliance in study-mandated prostate biopsies, we analyzed demographic, clinical and reported lifestyle data from the REDUCE trial. Methods: We retrospectively identified 8,062 men from REDUCE with at least 2-years of follow-up, and used multivariable logistic regression to test the association between baseline demographic and clinical characteristics and undergoing the study-mandated prostate biopsy at 2 years. We then examined whether missing any of these data was associated with undergoing a biopsy. Results: In REDUCE, 20% of men did not undergo a 2-year biopsy.On multivariable analysis, non-North American region was predictive of 35-55% increased likelihood of undergoing a 2-year biopsy (p ≤ 0.001). Being enrolled at a center that enrolled >10 subjects (2nd and 3rd tertile) was associated with a 40-49% increased likelihood of undergoing a 2-year biopsy (p < 0.001). Missing one or more baseline variables was associated with a 25% decreased likelihood of undergoing a 2-year biopsy (OR = 0.75; p = 0.002). Conclusions: In REDUCE, men outside North America, those at higher volume centers, and those with complete baseline data were more likely to undergo study mandated 2-year biopsies. Given prostate biopsy is becoming increasingly utilized as an endpoint in trials that are often multi-national, regional differences in compliance should be considered when designing future trials. Likewise, efforts are needed to ensure compliance in low-volume centers or among subjects missing baseline data.
Serum cholesterol and risk of lower urinary tract symptoms progression: Results from the Reduction by Dutasteride of Prostate Cancer Events study
ObjectiveTo determine if cholesterol is a risk factor for the development of lower urinary tract symptoms in asymptomatic men.MethodsA post‐hoc analysis of the Reduction by Dutasteride of Prostate Cancer Events (REDUCE) study was carried out in 2323 men with baseline International Prostate Symptom Score <8 and not taking benign prostatic hyperplasia or cholesterol medications. Cox proportion models were used to test the association between cholesterol, high‐density lipoprotein, low‐density lipoprotein and the cholesterol : high‐density lipoprotein ratio with incident lower urinary tract symptoms, defined as first report of medical treatment, surgery or two reports of an International Prostate Symptom Score >14.ResultsA total of 253 men (10.9%) developed incident lower urinary tract symptoms. On crude analysis, higher high‐density lipoprotein was associated with a decreased lower urinary tract symptoms risk (hazard ratio 0.89, P = 0.024), whereas total cholesterol and low‐density lipoprotein showed no association. After multivariable adjustment, the association between high‐density lipoprotein and incident lower urinary tract symptoms remained significant (hazard ratio 0.89, P = 0.044), whereas no association was observed for low‐density lipoprotein (P = 0.611). There was a trend for higher cholesterol to be linked with higher lower urinary tract symptoms risk, though this was not statistically significant (hazard ratio 1.04, P = 0.054). A higher cholesterol : high‐density lipoprotein ratio was associated with increased lower urinary tract symptoms risk on crude (hazard ratio 1.11, P = 0.016) and adjusted models (hazard ratio 1.12, P = 0.012).ConclusionsAmong asymptomatic men participating in the REDUCE study, higher cholesterol was associated with increased incident lower urinary tract symptoms risk, though the association was not significant. A higher cholesterol : high‐density lipoprotein ratio was associated with increased incident lower urinary tract symptoms, whereas higher high‐density lipoprotein was protective. These findings suggest dyslipidemia might play a role in lower urinary tract symptoms progression.