Health care epidemiology, characteristics, and regional variation of chiropractic care in Switzerland: a descriptive study using insurance claims data

BACKGROUND: Musculoskeletal disorders are a leading cause of disability and major driver of health care costs in Switzerland. Since chiropractors are musculoskeletal health care providers in this setting, we aimed to describe the health care epidemiology, characteristics, and regional variation of chiropractic care in Switzerland. METHOD: We conducted a retrospective descriptive study using administrative health insurance claims data of all ages from Helsana. Chiropractic care incidence cases were persons with first occurrence of chiropractic care in two study index years, 2018 and 2019. Chiropractic care prevalence cases had any chiropractic care over a 24-month prevalence period. We estimated (i) crude, (ii) sex-, age-, and region- standardised 12-month cumulative incidence, and (iii) 24-month prevalence of chiropractic care per 100,000 population. We characterised four mutually exclusive chiropractic care incidence subgroups based on additional health care use eight weeks before or after the index visit. Regional variation was visualised with choropleth maps. RESULTS: Among 1,137,904 and 1,196,760 persons with Helsana health insurance in 2018 and 2019, 17,148 (mean age 48.7 [SD, 18.4] years; 9,717 [56.7%] women) and 18,261 (mean age 48.2 [SD, 18.2] years; 10,421 [57.0%] women) persons had a chiropractic care incidence visit, respectively. The crude 12-month chiropractic care incidence was estimated at 1,507 (95% CI, 1,485 to 1,530) and 1,526 (1,504 to 1,548) cases per 100,000 in 2018 and 2019, respectively. Sex-, age-, and region-standardised incidence estimates were comparable to crude estimates. The 24-month prevalence of chiropractic care was estimated at 3,135 (3,105 to 3,166) per 100,000 population. The chiropractic case subgroup with the highest health care use had more comprehensive insurance models with lower deductibles. Incidence of chiropractic care varied across regions with the lowest incidence observed in Ticino and the highest in Espace Mittelland and Zurich. CONCLUSIONS: The incidence and prevalence of chiropractic care utilisation in Switzerland in 2018 and 2019 were markedly low. Chiropractic care subgroups differed in their characteristics, and incidence estimates varied across major regions. Further studies on the predictors and causes of chiropractic care underutilisation are warranted to inform accessible and equitable musculoskeletal and rehabilitation health services in Switzerland.