The disparity between men and women in developing fibromyalgia, where the female to male ratio is 7:1, causes many researchers to be suspicious of a link between sex hormones and chronic pain. Hormones may have a critical role in the onset, maintenance, and inhibition of pain. To determine if the clinical features and timing of hormonal changes have a relationship in a cohort of ethnically diverse individuals, a group of researchers from University of Miami Miller School of Medicine conducted a retrospective chart review of patients at the academic medical center in a period of one year.

“This retrospective chart review investigated differences in the prevalence of medical comorbidity between women with fibromyalgia and a control group women with chronic pain without fibromyalgia,” wrote Dr. Larry Brooks to describe the team’s article, “Assessing the Prevalence of Autoimmune, Endocrine, Gynecologic, and Psychiatric Comorbidities in an Ethnically Diverse Cohort of Female Fibromyalgia Patients: Does the Time from Hysterectomy Provide a Clue?“, which was published in Journal of Pain Research. “The specific aims were to compare the prevalence of autoimmune, psychiatric, endocrine, gynecologic pathology, the relationship between timing of gynecologic surgery, and pain onset.”

When reviewing patient charts, Dr. Brooks and three medical residents gathered data concerning diagnosis, year of pain onset, medical comorbidities, psychiatric comorbidities, surgical history, and date of hysterectomy, oophorectomy, or cystectomy. While date of pain onset and dates of surgical procedures were difficult to collect due to poor documentation, the researchers were able to adequately analyze 335 female patients for the study: 219 with fibromyalgia and 116 with chronic pain. They created a logistic regression model that incorporated the variables associated with fibromyalgia.

Autoimmune, total endocrine, and total gynecologic variables were significantly higher in the fibromyalgia group and were fit into the prediction model. Looking at gynecological features, the researchers noted that hysterectomy with oophorectomy, hysterectomy with oophorectomy and cystectomy, and total gynecologic surgeries were more likely to occur in the fibromyalgia patients. These surgeries preceded the onset of pain in 73.1% of patients.

“This study demonstrates that autoimmune, endocrine, and gynecologic pathologies occur more commonly in women with fibromyalgia than in those with chronic pain, which is consistent with findings in less ethnically diverse samples,” wrote the authors. Knowing that gynecologic surgery is associated with fibromyalgia in a wide variety of patients, gynecologists may wish to watch their patients for signs of fibromyalgia.