Glycemic Benefits with Adherence to Testosterone Therapy in Men with Hypogonadism and Type 2 Diabetes Mellitus.

Jenkins, Craig R; Rittel, Alex; Sturdivant, Rodney X; Wan, Jen; Clerc, Philip G; Manning, Evan; Jenkins, Lydia M; Wardian, Jana L; Graybill, Sky D

BACKGROUND While previous studies have demonstrated testosterone's beneficial effects on glycemic control in men with hypogonadism and Type 2 Diabetes, the extent to which these improvements are observed based on the degree of treatment adherence has been unclear. OBJECTIVES To evaluate the effects of long-term testosterone therapy in A1C levels in men with Type 2 Diabetes Mellitus and hypogonadism, controlling for BMI, pre-treatment A1C, and age among different testosterone therapy adherence groups. MATERIALS AND METHODS We performed a retrospective analysis of 1737 men with diabetes and hypogonadism on testosterone therapy for 5 years of data from 2008-2018, isolating A1C, lipid panels, and BMI results for analysis. Subjects were categorized into adherence groups based on quartiles of the proportion of days covered (> 75% of days, 51-75% of days, 26-50% of days and 0-25% of days), with >75% of days covered considered adherent to therapy. RESULTS Pre-treatment median A1C was 6.8%. Post-treatment median A1C was 7.1%. The adherent group, >75%, was the only group notable for a decrease in A1C, with a median decrease of -0.2 (p=0.0022). BMI improvement was associated with improved post-treatment A1C (p= 0.007). When controlling for BMI, age, and pre-treatment A1C, the > 75% adherence group was associated with improved post-treatment A1C (p < 0.001). DISCUSSION When controlling for all studied variables, testosterone adherence was associated with improved post-treatment A1C. The higher the initial A1C at the initiation of therapy, the higher the potential for lowering the patient's A1C with >75% adherence. Further, all groups showed some reduction in BMI, which may indicate that testosterone therapy may affect A1C independent of weight loss. CONCLUSION Even when controlling for improved BMI, pre-treatment A1C, and age, testosterone positively impacted glycemic control in diabetes patients with hypogonadism, with the most benefit noted in those most adherent to therapy (>75%).