Life events are positively associated with luteinizing hormone in middle age adult men: role of cortisol as a third variable.

Previous studies have tested the relationship between chronic stress and sex hormones, but inconsistent results have been found. One possibility is that this association may depend on other biological factors. This study examined the relationship between stressful life events (LE) and sex hormones in men, and whether cortisol is involved in this relationship. From a total number of 2906 men who completed a screening for the early detection of prostate cancer, 139 healthy men (mean ± SD age, 57.8 ± 5.7 years) were included in this study. Participants were assessed with the Holmes and Rahe questionnaire in relation to their experience of LE during the previous 1-5 years. Salivary and serum cortisol was measured at 08:00-09:00 h, as well as luteinizing hormone (LH), total testosterone, epinephrine (E) and norepinephrine (NE). LE weight sum and LE number positively correlated with LH (r = 0.293, p = 0.004; r = 0.220, p = 0.031, respectively). In a multiple regression analysis, LE-sum explained an additional and significant 10.4% of the variance in LH levels, after statistically controlling for the effects of age, waist circumference (WC) and BMI (F(1,90) = 6.61, p < 0.05). Importantly, cortisol interacted with LE in relation to total testosterone. In men with high cortisol values (≥15.4 µg/dl), there was a statistically significant positive relationship between LE number and total testosterone levels (p = 0.05), while LE were unrelated to total testosterone in men with low cortisol. LE correlated with sex hormones, predicting LH values, and in men with high cortisol levels shows a possible moderator effect of cortisol on the relationship between LE and total testosterone.