Trends in the treatment of fibromyalgia in South Korea between 2011 and 2018: a retrospective analysis of cross-sectional health insurance data

Objectives: Fibromyalgia treatment trends vary globally; however, the trend in South Korea has not been investigated yet. This study aimed to analyse the fibromyalgia treatment trends in South Korea.

Design: Retrospective, observational study using serial cross-sectional data.

Setting: The National Patient Samples of the Korean Health Insurance Review & Assessment Service from 2011 to 2018 were used.

Participants: A total of 31 059 patients with fibromyalgia were included in this study. The basic characteristics of the patients were stratified by sex, age and comorbidity. A patient was considered to have a condition if it was recorded as a principal diagnosis at least once in a year.

Primary and secondary outcome measures: Trends in the types of medical visits and prescribed treatments were investigated and the values are presented as rates per 100 patients. The types of pharmacological treatment were presented according to the existing clinical guidelines. Additionally, combination prescription trends and associated characteristics were investigated.

Results: Of the patients, 66.2% were female. Visits to internal medicine departments showed the most significant increase (2011: 11.34; 2018: 21.99; p<0.001). Non-pharmacological treatment rates declined (physical therapy 2011: 18.11; 2018: 13.69; p<0.001, acupuncture 2011: 52.03; 2018: 30.83; p<0.001). Prescription rates increased for analgesics, relaxants, antiepileptics and antidepressants. Non-steroidal anti-inflammatory drug prescriptions had the highest increase (2011: 27.65; 2018: 40.02; p<0.001). Serotonin-norepinephrine reuptake inhibitor prescriptions showed significant growth (2011: 2.4; 2018: 8.05; p<0.001). Prescription durations were generally longer for women (p<0.001), with higher rate increases in this group. Combinations of ≥3 medication classes increased (2011: 8.2; 2018: 9.64; p=0.041). Women were more likely to receive combination prescriptions (crude OR 1.47 (95% CI 1.29 to 1.68), adjusted 1.18 (95% CI 1.03 to 1.36)).

Conclusions: Our findings provide basic reference data for the development and application of national guidelines for fibromyalgia.