The conditions often coexist, and a bidirectional association is suggested.
Fibromyalgia tends to coexist with gastroesophageal reflux disease (GERD), and a bidirectional relationship is suggested-the incidence of GERD is higher in patients who have fibromyalgia, and the incidence of fibromyalgia is higher in patients who have GERD.
Researchers at National Yang-Ming University and Taipei Veterans General Hospital, Taipei, Taiwan, and other centers noted that GI symptoms are common in patients who have fibromyalgia, with up to 70% having irritable bowel syndrome (IBS). Patients with IBS often have GERD and vice versa, but the underlying mechanisms associating fibromyalgia with the risk of IBS and GERD are unclear.
Because the relationship between fibromyalgia and GERD is complex and has not been thoroughly investigated, the researchers conducted a retrospective cohort study using a nationwide data base, the National Health Insurance of Taiwan.
They reported their findings in Pain, the journal of the International Association for the Study of Pain.
They established 2 study arms-arm 1 with 35,117 patients who had fibromyalgia and arm 2 with 34,630 patients who had GERD-each with patients newly diagnosed between 2000 and 2010.
For each arm, they randomly selected 4-fold subjects who had neither fibromyalgia nor GERD from the same data base, frequency matched by sex, age, and diagnosis date, as the respective control cohorts.
Some of the results:
• The overall incidence of GERD was 1.6-fold greater in the fibromyalgia cohort than in the non-fibromyalgia cohort. The adjusted hazard ratio (aHR) was 1.27 after controlling for sex, age, comorbidities, and medications.
• The incidence rates of GERD were similar for men and women in the fibromyalgia cohorts and increased with age in both cohorts.
• GERD was independently associated with hyperlipidemia, depression, sleep disorder, alcohol-related illness, peptic ulcer disease, H. pylori infection, proton pump inhibitors, NSAIDs, and other comorbidities and medications.
• Sex, diabetes, hypertension, stroke, and liver cirrhosis had no strong influence on the association.
• The incidence of fibromyalgia ultimately was 1.45-fold higher in the GERD cohort than in the non-GERD cohort (5.76 vs 3.96 per 1000 person-years); the aHR was 1.44.
• A bidirectional relationship between fibromyalgia and GERD was suggested.
• The risk of GERD in patients with fibromyalgia was found to be greater than the risk of fibromyalgia in patients with GERD.
• However, GERD takes longer to develop in patients with fibromyalgia than fibromyalgia takes to develop in patients with GERD.
“This study reveals, for the first time, a bidirectional association between the onset of FM and GERD in patients with GERD and FM, respectively,” the authors concluded. “The incidence rates of FM in the GERD cohort and those of GERD in the FM cohort increased with age in both directions. However, hazards relative to the corresponding comparison cohort attenuated with the increase of age.”
Wang JC, Sung FC, Men M, et al. “Bidirectional association between fibromyalgia and gastroesophageal reflux disease: two population-based retrospective cohort analysis.” Pain. 2017 Oct;158(10):1971-1978. doi: 10.1097/j.pain.0000000000000994.