Variability in cyclicity affects pain and other symptoms in female fibromyalgia syndrome patients

Objective: This study was designed to investigate if the hormonal changes in the menstrual cycle influence pain and other symptoms in fibromyalgia syndrome [FMS] patients with and without premenstrual dysphoric disorder [PDD] compared to healthy control subjects [HCS], and to assess the degree of concomitant affective disorder in the two subgroups of patients. Methods: Sixteen FMS patients and 15 HCS recorded 15 different symptoms daily during one ovulatory cycle. The mean values of each symptom per day of each patient group and HCS were calculated. Comparisons were made between four different phases of the menstrual cycle in the patient groups and HCS. Evaluation of possible concomitant affective disorder was made as well. Results: There was a significant difference in pain, physical and psychological symptoms between the ovulatory and perimenstrual phases in all FMS patients with emphasis in the PDD patients. Such a difference of the symptoms was not seen in the corresponding HCS. Compared to the HCS, all FMS patients: had more severe psychological problems and were less happy during the luteal phase and perimenstrually. Forty-four percent of all the FMS patients had PDD and the same proportion also had some kind of affective disorder, although most of them of a lesser degree. Conclusion: The results indicate that the changes of the gonadal steroids during the menstrual cycle influence the pattern and severity of the symptoms in FMS patients significantly more than in UCS. The affective disturbances were distributed fairly equally in the PDD and non-PDD patients and were of minor to moderate degree.