BackgroundAtrial fibrillation (AF), an inflammatory process involving arrhythmia, is associated with severe morbidity and mortality and commonly seen in patients with diabetes mellitus (DM). The effect of metformin, the most commonly used medication for patients with DM, on AF has not been investigated. The primary aim of this study was to examine whether metformin prevented the occurrence of AF in type 2 DM patients by analyzing a nationwide, population-based dynamic cohort. Additionally, we investigated the effect of metformin on tachycardia-induced myolysis and oxidative stress in atrial cells.MethodsThe study population included 645,710 patients with type 2 diabetes and not using other anti-diabetic medication from a subset of the Taiwan National Health Insurance Research Database. Of these patients, those who used metformin were categorized as the user group, and the remaining were classified as the non-user group. The time-dependent Cox’s proportional hazard model was used to examine the effect of metformin on AF and the status of metformin use was treated as a time-dependent covariate. HL-1 atrial cells were paced with or without metformin, and then troponin and heavy-chain-myosin were measured as markers of myolysis.ResultsAfter 13 years of follow-up, 9,983 patients developed AF with an incidence rate of 1.5% (287 per 100,000 person-years). After adjusting for co-morbidities and medications, metformin independently protected the diabetic patients from new-onset AF with a hazard ratio of .81 (95% confidence interval 0.76-0.86, p < 0.0001). Metformin significantly decreased the extent of pacing-induced myolysis and the production of reactive oxygen species.ConclusionMetformin use was associated with a decreased risk of AF in patients with type 2 DM who were not using other anti-diabetic medication, probably via attenuation of atrial cell tachycardia-induced myolysis and oxidative stress.Electronic supplementary materialThe online version of this article (doi:10.1186/s12933-014-0123-x) contains supplementary material, which is available to authorized users.

BackgroundWhether dipeptidyl peptidase-4 inhibitor (DPP4i) is associated with a lower risk of new-onset atrial fibrillation (AF) in patients with diabetes remains unclear. This study aimed to evaluate the risk of AF associated with use of DPP4i among a longitudinal cohort of patients with diabetes.MethodsOver a 3-year period, 480,000 patients with diabetes were analyzed utilizing Taiwan’s National Health Insurance Research Database and 90,880 patients taking metformin as first-line therapy were enrolled. Patients were further divided into two groups: (1) DPP4i users: those taking DPP4i and (2) non-DPP4i users: those prescribed other hypoglycemic agents (HAs) as second-line drug. Study end point was defined by diagnosis of AF, addition of any third-line HA, or the end of the study period (December 31, 2013), whichever came first.ResultsA total of 16,017 DPP4i users and 74,863 non-DPP4i users were eligible for the study. For the DPP4i group, most patients were prescribed sitagliptin (n = 12,180; 76%). Among the non-DPP4i group, most patients took sulfonylurea (n = 60,606; 81%) as their second-line medication. DPP4i users were associated with a lower risk of new-onset AF compared with non-DPP4i users after propensity-score weighting (hazard ratio 0.65; P < 0.0001). Subgroup analysis showed that DPP4i user were associated with a lower risk of new-onset AF compared with non-DPP4i users in most subgroups. Multivariate analysis indicated that use of DPP4i was associated with lower risk of new-onset AF and age > 65 years, presence of hypertension, and ischemic heart disease were independent risk factors for new-onset AF.ConclusionsAmong patients with diabetes prescribed with metformin, the patients with DPP4i as second HA were associated with a lower risk of AF compared with the patients with other drugs as second HAs in real-world practice.Electronic supplementary materialThe online version of this article (10.1186/s12933-017-0640-5) contains supplementary material, which is available to authorized users.

Background Evidence of adverse clinical outcomes for non-vitamin K antagonist oral anticoagulant (NOACs) and warfarin in patients with atrial fibrillation (AF) and diabetes mellitus are limited. We investigated the effectiveness, safety, and major adverse limb events for NOACs versus warfarin among diabetic AF patients. Methods In this nationwide retrospective cohort study collected from Taiwan National Health Insurance Research Database, we identified a total of 20,967 and 5812 consecutive AF patients with diabetes taking NOACs and warfarin from June 1, 2012, to December 31, 2017, respectively. We used propensity-score stabilized weighting to balance covariates across study groups. Results NOAC was associated with a lower risk of major adverse cardiovascular events (MACE) (adjusted hazard ratio (aHR):0.88; [95% confidential interval (CI) 0.78–0.99]; P = 0.0283), major adverse limb events (MALE) (aHR:0.72;[95% CI 0.57–0.92]; P = 0.0083), and major bleeding (aHR:0.67;[95% CI 0.59–0.76]; P < 0.0001) compared to warfarin. NOACs decreased MACE in patients of ≥ 75 but not in those aged < 75 years (P interaction = 0.01), and in patients with ischemic heart disease (IHD) compared to those without IHD (P interaction < 0.01). For major adverse limb events, the advantage of risk reduction for NOAC over warfarin persisted in high risk subgroups including age ≥ 75 years, chronic kidney disease, IHD, peripheral artery disease, or use of concomitant antiplatelet drugs. Conclusion Among diabetic AF patients, NOACs were associated with a lower risk of thromboembolism, major bleeding, and major adverse limb events than warfarin. Thromboprophylaxis with NOACs should be considered in the diabetic AF population with a high atherosclerotic burden.

ObjectivesThe aim of this study was to estimate the risk of hyperuricaemia and gout in people with hypothyroid or hyperthyroid status.MethodsThis study analyzed data from individuals who participated in health screening programs at Chang Gung Memorial Hospital in northern Taiwan (2000–2010). Participants were categorized as having euthyroid, hypothyroid, or hyperthyroid status according to their thyroid-stimulating hormone (TSH) levels. Multinomial logistic regression models were used to calculate the odds ratios (95% CI) for hyperuricaemia and gout in participants with thyroid dysfunction compared to euthyroid participants.ResultsA total of 87,813 (euthyroid, 83,502; hypothyroid, 1,460; hyperthyroid, 2,851) participants were included. The prevalence of hyperuricaemia was higher in hyperthyroid subjects (19.4%) than in euthyroid subjects (17.8%) but not in hypothyroid subjects (19.3%). The prevalence of gout was significantly higher in both hypothyroid (6.0%) and hyperthyroid (5.3%) subjects than in euthyroid subjects (4.3%). In men, hypothyroid or hyperthyroid status was not associated with hyperuricaemia. However, hypothyroid or hyperthyroid status was associated with ORs (95% CI) of 1.47 (1.10–1.97) and 1.37 (1.10–1.69), respectively, for gout. In women, hypothyroid status was not associated with hyperuricaemia or gout. However, hyperthyroid status was associated with ORs (95% CI) of 1.42 (1.24–1.62) for hyperuricaemia and 2.13 (1.58–2.87) for gout.ConclusionsBoth hyperthyroid and hypothyroid status were significantly associated with gout and weakly associated with hyperuricaemia. A thyroid function test for gout patients may by warranted.

Background Whether sodium glucose co-transporter 2 inhibitors (SGLT2i) are associated with a lower risk of cardiovascular as well as adverse lower limb events in patients with type-2 diabetes mellitus (T2DM) and concomitant peripheral artery disease (PAD) is unclear. We aimed to evaluate the risk of cardiovascular and limb events, and death associated with the use of SGLT2i compared with dipeptidyl peptidase-4 inhibitors (DPP4i) among a longitudinal and national cohort of patients with T2DM. Methods In this nationwide retrospective cohort study based on the Taiwan National Health Insurance Research Database, we identified a total of 11,431 and 93,972 consecutive T2DM patients with PAD taking SGLT2i and DPP4i, respectively, from May 1, 2016, to December 31, 2017. We used 1:1 propensity score matching (PSM) to balance covariates across study groups. Patients were followed from the drug index date until the occurrence of clinical outcomes, death, discontinuation of the index drug, or the end of the study period, whichever occurred first. Results Overall, 56% and 44% of the patients were treated with dapagliflozin and empagliflozin, respectively. The use of SGLT2i had comparable risks of ischemic stroke and acute myocardial infarction, and was associated with lower risks of congestive heart failure (CHF) [hazard ratio (HR): 0.66; 95% confidence interval (CI) 0.49–0.89; p = 0.0062], lower limb ischemia requiring revascularization (HR: 0.73; 95% CI 0.54–0.98; p = 0.0367) or amputation (HR: 0.43; 95% CI 0.30–0.62; p < 0.0001), and cardiovascular death (HR: 0.67; 95% CI 0.49–0.90; p = 0.0089) when compared with the DDP4i group after PSM. The subgroup analysis revealed consistent results for CHF and major adverse limb outcomes for SGLT2i versus DPP4i among patients aged ≥ 75 years, the presence of chronic kidney disease and established cardiovascular disease was consistent with the main analysis. Conclusions SGLT2i were associated with lower risks of CHF and adverse lower limb events compared with DPP4i among patients with T2DM and PAD in real-world practice.