Circadian rhythms of prolactin and thyroid-stimulating hormone during the menstrual cycle and early versus late sleep deprivation in premenstrual dysphoric disorder

The present study extended previous work by examining whether disturbances in the circadian rhythms of prolactin (PRL) and thyroid-stimulating hormone (TSH) distinguish patients with premenstrual dysphoric disorder (PMDD) from normal volunteers. In addition, the effects of therapeutic interventions with early and late partial sleep deprivation were explored. Both PRL and TSH levels were measured every 30 min from 18:00 h to 09:00 h during midfollicular and late luteal menstrual cycle phases in 23 PMDD patients and 18 normal volunteers. Hormone levels were measured again after a randomized crossover trial of early (sleep 03:00-07:00 h) versus late (sleep 21:00-01:00 h) partial sleep deprivation administered in two separate luteal phases. Compared with normal volunteers, PMDD patients had higher PRL concentrations, consistent with previous findings. TSH rhythms occurred earlier in PMDD than in normal subjects. PRL levels decreased and TSH levels increased with sleep deprivation compared with baseline conditions. The timing of PRL secretion shifted earlier with late sleep deprivation and later with early sleep deprivation. Although circadian disturbances of PRL and TSH were found in PMDD patients compared with normal volunteers, the therapeutic effects of early and late sleep deprivation do not appear to be mediated by correcting these disturbances.