Abstract
INTRODUCTION: There are some data suggesting that there is a relationship between the magnitude of Peyronie's disease (PD)-associated penile curvature and low serum testosterone. AIM: To evaluate the relationship between PD associated penile deformity and total testosterone (TT) and free testosterone (FT) levels. METHODS: We identified patients diagnosed with PD who had early morning TT measurements. Because laboratories have different reference values, we analyzed testosterone values 2 ways, as raw values and as standardized values (TT and FT values converted into z-scores for each laboratory). Deformity assessment was conducted during an intracavernosal injection-induced rigid erection. The association between T levels and magnitude of penile curvature was analyzed in a number of ways. First, an independent measure t-test tested differences in curvature degree by TT groups (low T: <300 ng/dL; normal T: ≥300 ng/dL). Second, an association was sought between T levels based on quartiles of the normal range (<300, 300-450, 450-600, and >600 ng/dL). These analyses were conducted for both TT and FT levels and using both raw and standardized T values. Third, multivariable analysis using multiple linear regression was performed in an attempt to define predictors of the degree of penile curvature. Factors entered into the model included: TT level, FT level, patient age, race (white vs other), number of co-morbidities, body mass index, presence of erectile dysfunction, duration of PD, and prostatectomy (yes vs no). MAIN OUTCOME MEASURES: The relationship between T levels and the magnitude of penile curvature. RESULTS: 184 subjects met all study criteria. Average age was 54 ± 12 years. Mean TT level was 425 ± 176 ng/dL, and mean curvature magnitude was 35° ± 19°. The percent of subjects in the first through fourth TT quartiles was 26%, 34%, 24%, and 16%. As a continuous variable, there was no association between TT levels (r = -0.01, P = .95) or FT levels (r = -0.08, P = .30) and the curvature magnitude. When examining TT groups, there was no difference in mean curvature between the low TT group and the normal TT group (35.4° ± 17° vs 34° ± 20°, P = .70). When analyzing the TT and FT levels standardized into z-scores, there was no association between degree of curvature and TT z-scores (r = -0.003, P = .95) and FT z-scores (r = -0.08, P = .43). There was also no association between testosterone levels and degree of curvature in the multivariable model. CONCLUSIONS: There does not appear to be any association between testosterone levels and the magnitude of PD-associated penile deformity. Mulhall JP, Matsushita K, Nelson CJ. Testosterone Levels Are Not Associated With Magnitude of Deformity in Men With Peyronie's Disease. J Sex Med 2019;16:1283-1289.