Incidence of atrial fibrillation among non-cancer-related opioid users in the Korean National Health Insurance Service database, 2009-2018

Opioids are widely used over short periods to control pain due to cancer or surgery; however, long-term opioid use has become a major public health issue in many countries, including Republic of Korea. 1 Among the adverse effects of chronic opioid treatment, 2 the relationship between prescribed opioids and the cardiovascular system has recently become a focus of research.As a result, non-cancer-related chronic opioid use has been shown to be an independent risk factor for cardiovascular disease (CVD)-related mortality.3 Although the mechanisms by which chronic opioid use induces CVD are not well defined, arrhythmias have been suggested to play a role.A recent meta-analysis 4 reported an increased risk of atrial fibrillation (AF) with opioid use; however, it included patients with cancer, studies of narcotics that are considered illegal in Republic of Korea, and a notable lack of research conducted in Republic of Korea.Opioid prescriptions for chronic non-cancer-related pain are more strictly controlled in Korea than in Europe and the United States, and exposure to illicit opioid use is therefore relatively unlikely in Republic of Korea.5 This study measured the risk of AF in patients receiving chronic non-cancer-related opioids using a nationwide population-based dataset in Republic of Korea.This population-based retrospective cohort study used data from the 2009 to 2018 National Health Insurance Service (NHIS), which covers 97% of the Korean population through mandatory subscriptions.The NHIS database contains all inpatient and outpatient claims records, including demographics, diagnostic codes, medical tests or procedures, and drug prescriptions.For the NHIS cohort, we merged data from the National Health Screening Program.6The screening included detailed lifestyle questionnaires, biochemical results, and anthropometric measurements.