Comparison of self-assessment of libido at the 2 year point showed a dramatic improvement in the testosterone group compared to that in the controls (Fig. 1). The incidence of new illnesses during the course of the study was not significantly different in the two groups for coronary artery disease, peripheral vascular disease, myocardial infarctions, angina, diabetes mellitus, or transient ischemic attacks (Table 3). Benign prostatic hypertrophy (BPH) has long been a concern associated with long term testosterone administration. This study found that the control group had a higher rate of BPH than the study group, but the difference was not statistically significant.
The 2 yr changes in serum and hematocrit values of the two groups are compared in Table 2. There were no significant differences in the prostate-specific antigen concentration. The urea nitrogen to creatinine ratio dropped in the study group, but the change was not statistically significant. Only hematocrit showed a significant increase in the testosterone-treated group compared to that in controls. Eleven subjects (24%) in the testosterone group developed polycythemia (hemoglobin, >17 g/dL; hematocrit, >52%), warranting temporary withdrawal of testosterone therapy or phlebotomy. Of these, the first occurrence of polycythemia was within the first year of therapy in six (33%) subjects, between 1–2 yr in 3 (6.7%) subjects, and beyond 2 yr in two (4.4%) subjects.