PROs were collected every months starting at enrollment

PROs were collected every 6 months starting at enrollment allowing for detailed longitudinal evaluation of sexual function and identification of predictors of reduced sexual function over time. This information may prove valuable for counseling patients who are considering AS. An overall decline in sexual function was observed during the 24‐month study period, with older age at enrollment and longer time on surveillance as independent predictors for reduced sexual function over time. The observed small magnitude of decline is confirmed by recently published data from the prospective Comparative Effectiveness Analysis of Surgery and Radiation study of 3,691 men with newly diagnosed PCa [24]. Pretreatment EPIC‐26 SF scores decreased by 1.24 points with every 1 year increase in age. The Massachusetts Male Aging Study also demonstrated an increased incidence of ED with advancing age [25]. These findings further support our assertion that additional reading the decline in sexual function observed in our AS cohort is related to aging. In our AS cohort, total MAX‐PC scores and the PCa anxiety sub‐scores also saw a gradual, small decline over time. Our results support data from a recent study of 150 Dutch men with low‐risk PCa managed with AS [26]. This study found that general anxiety and fear of progression significantly decreased during the first 18 months of enrollment on AS. Reductions in anxiety could be the result of increased patient acceptance of AS as a safe management strategy for PCa and better tolerance of the repeated PB and PSA testing required for compliance with AS protocols. These findings are potentially important for clinicians attempting to manage patient expectations and may provide reassurance for patients considering AS. While we did not identify a correlation between MAX‐PC scores and SD, studies in men after surgical treatment for PC have found that increased PCa anxiety is associated with poor sexual satisfaction and function [27]. Taken together, men entering AS can anticipate an age related decline in sexual function, but may benefit from reduced disease‐related anxiety over time.
General comorbidity scores have been associated with reduced overall sexual function in men on AS; however, to our knowledge, individual comorbidities as risk factors for decreased sexual function have not been examined. We identify diabetes as an independent predictor of reduced sexual function over time in men on AS. This adds to the extensive body of literature supporting diabetes as a risk factor for SD, with rates of ED among diabetics ranging from 32% to 90% depending on the patient population, diabetes type, severity, and duration of disease [28]. We also found that increased baseline PSA predicted a more rapid decline in sexual function over time. Considering previous epidemiological studies, which have found strong associations between benign prostatic hyperplasia (BPH), LUTS and SD [29,30], it is possible that the association between PSA and declining SF in our study is related to the presence of BPH in patients with higher PSA. However, we did not identify LUTS or prostate volume as predictors of SD in our analysis, therefore, no definitive conclusions can be made.

Conclusions

Introduction
Hypogonadism affects approximately 2–4 million men in the United States, and is characterized by low serum testosterone (T) levels in association with signs and symptoms of hypogonadism including fatigue, decreased libido, erectile dysfunction, depression, anemia, and decreased muscle mass and bone density [1,2]. In addition to ameliorating hypogonadal symptoms [1,3], T therapy (TTh) can lead to increased muscle mass and bone density [4–6], and reversal of the metabolic syndrome [2,7]. However, TTh is associated with potential adverse effects including elevated serum estrogen levels, gynecomastia, local reactions, alterations in serum lipids, erythrocytosis, testicular atrophy, male infertility, and cardiovascular effects [1,2,8–11].