Differential effects of antiepileptic drugs on sexual function and reproductive hormones in men with epilepsy: Interim analysis of a comparison between lamotrigine and enzyme-inducing antiepileptic drugs

Abstract

Purpose: We compared sexual function and reproductive hormone levels among men with localization-related epilepsy (LRE) taking various antiepileptic drugs (AEDs) and normal controls (NC). Methods: Subjects were 63 men with LRE [enzyme-inducing (EI) AEDs, 36; lamotrigine (LTG), 18; no AEDs, 9] and 18 NC. Sexual interest and function (S-score), hormone levels [bioactive testosterone (BAT) and estradiol (BAE)], hormone ratios [BAT/BAE], and gonadal efficiency [BAT/luteinizing hormone (LH)] were compared among the groups. Results: S-scores, BAT levels, BAT/BAE, and BAT/LH were significantly lower in the EIAED group than in NC or LTG groups. Sex hormone-binding globulin (SHBG) was significantly higher in the EIAED group than in all other groups. Of men with LRE, 23.8% had abnormally low S-scores: 33.3% taking EIAEDs, 5.5% taking LTG, and 22.2% taking no AEDs (p < 0.01). BAT was low in 55.6% taking EIAEDs as compared with 33.3% taking LTG and 33.3% taking no AEDs (p < 0.05). Among men with low S-scores, 86.7% had low BAT as compared with 33.3% of men with normal scores (p < 0.01). BAT decline with age was greater among men with LRE than in controls (3.75 vs. 1.80 ng/dl/yr). The slope showed no significant difference among LRE groups. However, 89% of 40- to 50-year-old men taking EIAEDs had low BAT as compared with 33% taking LTG and 33% taking no AED (p < 0.01). Conclusions: Sexual function, BAT levels, BAT/BAE, and gonadal efficiency are greater with LTG than with EIAED. Abnormally low BAT levels are reached at an earlier age with EIAEDs than with LTG.