BackgroundWhile Denmark is well known for its plethora of registers. Many studies are conducted on research databases that only cover parts of Denmark, and regional differences could potentially threaten these studies’ external validity. The aim of this study was to assess sociodemographic and health related homogeneity of the five Danish regions.MethodsWe obtained descriptive data for the five Danish regions, using publicly available data sources: Statbank Denmark, the Danish Ministry of Economic Affairs, and Medstat.dk. These data sources comprise aggregate data from four different nationwide registers: The Danish National Patient Register, The Danish Civil Registration System, The Danish Register of Medicinal Product Statistics, and The Danish National Health Service Register for Primary Care. We compared the Danish regions regarding demographic and socioeconomic characteristics, health care utilization, and use of medication. For each characteristic, one-year prevalence was obtained and analyses were performed for 2013 and 2008 to account for possible change over time.ResultsIn 2013, 5,602,628 persons were living in Denmark. The mean age was 40.7 years in the entire Danish population and ranged between 39.6 to 42.4 years in the five regions (coefficient of variation between regions [CV] = 0.028). The proportion of women in Denmark was 50.4% (CV = 0.009). The proportion of residents with low education level was 28.7% (CV = 0.051). The annual number of GP contacts was 7.1 (range: 6.7–7.4, CV = 0.040), and 114 per 1,000 residents were admitted to the hospital (range: 101–131, CV = 0.107). The annual number of persons redeeming a prescription of any medication was 723 per 1,000 residents (range: 718–743, CV = 0.016). Analyses for 2008 showed comparable levels of homogeneity as for 2013.ConclusionsWe found substantial homogeneity between all of the five Danish regions with regard to sociodemographic and health related characteristics. Epidemiologic studies conducted on regional subsets of Danish citizens have a high degree of generalizability.

Patients with atrial fibrillation discontinuing anticoagulant therapy are left unprotected against ischaemic stroke. Further, switching between oral anticoagulants may be associated with a transiently increased risk of bleeding or thromboembolism. However, there is a paucity of real-life data on pattern of switching and discontinuation of oral anticoagulants. To address this, we conducted a nationwide drug utilization study including all registered Danish atrial fibrillation patients initiating a non-VKA oral anticoagulant (NOAC) between August 2011 and February 2016. We assessed changes in anticoagulant treatment, including switching between oral anticoagulants and discontinuation of NOACs, and explored patient characteristics predicting these changes.We identified 50,632 patients with atrial fibrillation initiating NOAC therapy within the study period. The majority initiated dabigatran (49.9%) and one-third had previously used VKA. Within 1 year, 10.1% switched to VKA, 4.8% switched to another NOAC and 14.4% discontinued treatment. The frequencies of switching to VKA and discontinuation were highest among NOAC users of young age (<55 years) and with low CHA 2 DS 2 -VASc score (=0). However, the majority of patients (87.3%) stopping NOAC treatment had a CHA 2 DS 2 -VASc score ≥1.We conclude that switching from VKA to NOAC, and to a lesser extent from NOAC to VKA, is common, as is early treatment discontinuation. The majority of treatment changes are observed in patients at increased risk of stroke. More research is warranted on the risks of bleeding and thromboembolism associated with switching and discontinuation of NOACs as well as the underlying reasons why these treatment changes occur.

AimsSwitching between oral anticoagulants and treatment discontinuation are common events related to therapy with non-vitamin K antagonist oral anticoagulants (NOACs). However, knowledge on the reasons leading to these treatment changes is scarce. The aim of this study was to identify clinical events preceding anticoagulant switching and NOAC discontinuation during oral anticoagulant therapy in patients with atrial fibrillation.Methods and resultsWe performed a nationwide register-based study including Danish atrial fibrillation patients initiating a NOAC between August 2011 and February 2016 (n = 50 623). We explored potential reasons leading to changes in anticoagulant treatment by identifying clinical events preceding switches from vitamin K antagonists (VKA) to NOAC, switches from NOAC to VKA, and discontinuations of NOACs. Among 23 531 anticoagulant users changing treatment, we identified 13 295 switches from VKA to NOAC, 5206 switches from NOAC to VKA, and 8995 discontinuations of NOACs. Approximately half of all treatment changes were preceded by a hospitalization. A relevant specific clinical event or procedure was identified prior to 18.3% of switches from VKA to NOAC, prior to 23.0% of switches from NOAC to VKA, and prior to 26.6% of discontinuations. Switches from VKA to NOAC were most often preceded by thromboembolic events (7.0%), whereas cardioversion was the most common specific event prior to a switch from NOAC to VKA (11.4%). Discontinuations were most often preceded by bleeding events (7.6%).ConclusionFor about one in five patients, treatment changes during anticoagulant therapy were preceded by a major clinical event. However, the majority of patients changed treatment for reasons not recorded in health registries.

We aimed to provide detailed utilization data on the total use of non-vitamin K antagonist oral anticoagulants (NOACs) since their introduction in 2008. Using the nationwide Danish National Prescription Registry, we identified all individuals filling prescriptions for NOACs 2008-2016. We reported the development in incident and prevalent users and explored baseline characteristics and treatment persistence according to treatment indication. A total of 126,691 NOAC users were identified within the Danish population of 5.7 million inhabitants. The annual incidence and prevalence increased rapidly reaching 10 and 17 per 1000 individuals in 2016. Patients received NOACs due to atrial fibrillation (AF) (43%), venous thromboembolism (VTE) prophylaxis after arthroplastic surgery (17%), VTE (12%) and no registered indication (28%). The most frequently used NOAC was rivaroxaban (n = 52,431), followed by dabigatran (n = 47,067), apixaban (n = 27,116) and edoxaban (n = 77). The proportion of AF and VTE patients initiating low-dose NOACs were between 23% and 50%. Patients treated with NOAC for VTE primarily received rivaroxaban. We observed a trend towards increased use of apixaban and rivaroxaban at the expense of dabigatran. Treatment persistence was highly dependent on treatment indication. Persistence to NOAC after 3 years was only 62% in AF compared to 28% for VTE. We documented an accelerating increase in the use of all four NOACs in the first 8 years after introduction. We have identified areas requiring further attention, including reasons for missing indications, potential inappropriate dosing and low long-term persistence with NOACs in patients with AF.

Purpose To describe the use of tramadol and other analgesics in Denmark focusing on the impact of media attention (June and December 2017) and regulatory actions (September 2017 and January 2018) on the use of tramadol. Methods Using nationwide registries, we identified all adults who filled a prescription for tramadol and other analgesics from 2014 to 2019. We described incidence rates, prevalence proportions, and total use of tramadol and other analgesics over time. We also described switching between analgesics, treatment duration, skewness in drug use, and doctor-shopping. Results From early 2017 until the end of 2019, total tramadol use decreased markedly while the use of morphine and oxycodone decreased slightly. The quarterly prevalence of tramadol use decreased from 32/1000 individuals in 2014 to 18/1000 at the end of 2019, dropping mainly at the time of media attention. Concomitantly, the quarterly prevalence increased for oxycodone (from 5.1 to 8.2) and morphine (from 8.5 to 9.8), mainly due to more short-term and sporadic users, and decreased for codeine (14 to 9.6). From 2014 to mid-2017, the incidence of tramadol use was stable (around 2.2/1000 person-months) but dropped in June 2017 to 1.7/1000, coinciding with the media attention. The incidence of tramadol use continued to decrease (to 1.1/1000 at the end of 2019). Conclusion We identified a decline in tramadol use coinciding with the media attention in 2017 and continuing during regulatory actions. There was generally no evidence of unintended effects on the utilization of opioids related to the media attention and regulatory actions.