Background: This retrospective chart review investigated differences in the prevalence of medical comorbidity between women with fibromyalgia (FM) (n=219) and a control group women with chronic pain (CP) without FM (n=116). The specific aims were to compare the prevalence of autoimmune, psychiatric, endocrine, gynecologic pathology, the relationship between timing of gynecologic surgery, and pain onset. We additionally sought to compare the number of comorbidities in an ethnically diverse cohort.
Methods: This was a retrospective chart review of patients seen in FM or CP clinics at an academic medical center in 2009-2010.
Results: Logistic regression modeling found that gynecologic, endocrine, and autoimmune diagnoses were independently associated with a diagnosis of FM. Detailed analyses showed that thyroid disease (P<0.01) and gynecologic surgery (P<0.05) were significantly more common in FM. Women with FM were more likely to have multiple autoimmune, endocrine, gynecologic, or psychiatric pathologies. A relationship was observed between the timing of gynecologic surgery and pain onset in FM, with more surgeries observed in the years just prior to pain onset or in the year after pain onset. A similar pattern was not found in the control group.
Conclusion: This study demonstrates that autoimmune, endocrine, and gynecologic pathologies occur more commonly in women with FM than in those with CP, which is consistent with findings in less ethnically diverse samples. Moreover, a relationship was found between timing of pain onset and gynecologic surgery. A larger prospective study of the relationship between gynecologic surgery and pain onset in FM is warranted.
Keywords: autoimmune; chronic pain; fibromyalgia; sex hormones; thyroid.