Herpesviruses affect the development of dementia. We investigated the association between herpes infection and subsequent diagnoses of dementia. Data from the National Health Insurance Service of South Korea were used. Patients aged ≥50 years with the relevant diagnostic codes in the reference year 2009 were included and prospectively reviewed from January 2010 to December 2018. All study participants were followed from the index date until the onset of dementia, death, or the study endpoint. The three cohorts comprised 92,095 patients with herpes simplex virus (HSV) infections, 97,323 patients with varicella-zoster virus (VZV) infections, and 183,779 controls. During the follow-up period, 15,831 (17.19%) subjects with HSV infection and 17,082 (17.55%) VZV-infected subjects, compared to 27,028 (14.17%) control subjects, were subsequently diagnosed with dementia (all, P < .001). The adjusted hazard ratio for developing dementia was found to be 1.18 (95% confidence interval [CI]; 1.16–1.20) in HSV and 1.09 (95% CI; 1.07–1.11) in VZV patients (all, P < .001). HSV1 infections such as oral or ocular subtypes, but not HSV2, anogenital subtype, were associated with dementia, including several subtypes such as Alzheimer’s disease (AD), vascular dementia, and dementia with Lewy bodies. VZV infection is also associated with AD. In this Korean nationwide population-based cohort study, both HSV and VZV infections were associated with a higher risk of dementia, particularly AD. Among the subtypes of HSV infection, HSV1 is associated with a risk of dementia. Further studies including appropriate public health interventions could evaluate the causality of these relationships.

Kim DE, et al. J Korean Med Sci. 2023 Jul;38(31):e239. https://doi.org/10.3346/jkms.2023.38.e239

Background/Aims: Gastrointestinal bleeding (GIB) risk for non-vitamin K antagonist oral anticoagulants (NOACs) compared with warfarin is largely unknown. We aimed to determine the risk of overall and post-polypectomy GIB for NOACs and warfarin. Methods: Using the Korean National Health Insurance database, we created a cohort of patients who were newly prescribed NOACs or warfarin between July 2015 and December 2017 using propensity score matching (PSM). Kaplan-Meier analysis with log-rank test was performed to compare the risk of overall and post-polypectomy GIB between NOACs (apixaban, dabigatran, and rivaroxaban) and warfarin. Post-polypectomy GIB was defined as bleeding within 1 month after gastrointestinal endoscopic polypectomy.Results: Out of 234,206 patients taking anticoagulants (187,687 NOACs and 46,519 warfarin), we selected 39,764 pairs of NOACs and warfarin users after PSM. NOACs patients showed significantly lower risk of overall GIB than warfarin patients (log-rank P<0.001, hazard ratio, 0.86; 95% confidence interval, 0.78–0.94; P=0.001). Among NOACs, apixaban showed the lowest risk of GIB. In the subgroup of 7,525 patients who underwent gastrointestinal polypectomy (lower gastrointestinal polypectomy 93.1%), 1,546 pairs were chosen for each group after PSM. The NOACs group showed a high risk of post-polypectomy GIB compared with the warfarin group (log-rank P=0.001, hazard ratio, 1.97; 95% confidence interval, 1.16–3.33; P=0.012).Conclusions: This nationwide, population-based study demonstrates that risk of overall GIB is lower for NOACs than for warfarin, while risk of post-polypectomy GIB is higher for NOACs than for warfarin.

Kim YA, et al. J Gynecol Oncol. 2021 Jul;32(6):e85. https://doi.org/10.3802/jgo.2021.32.e85

Purpose: The cardiovascular (CV) benefits of sodium-glucose cotransporter 2 inhibitors (SGLT2i) are well established, but their effects on lower limb events (LLEs) remain inconclusive, with conflicting findings from clinical trials and real-world studies. This study aimed to assess the risks of CV and LLEs associated with SGLT2i compared to dipeptidyl peptidase-4 inhibitors (DPP-4i) in patients with type 2 diabetes. Patients and Methods: The study included patients with type 2 diabetes who were newly prescribed SGLT2i or DPP-4i using data from the National Health Insurance Service in South Korea. A 1:1 propensity score matching method was used to assign 97,584 patients to the SGLT2i and DPP-4i groups. The study endpoints included all-cause mortality, CV events, and LLEs—a composite outcome encompassing diabetic foot or ulcer, amputation, debridement, graft transplantation or flap operation, and revascularization. Results: Over a median follow-up of 2.74 years, the SGLT2i group had a lower incidence of all-cause mortality (hazard ratio [HR] 0.63, 95% CI 0.51– 0.78), heart failure (HR 0.85, 95% CI 0.78– 0.93), ischemic stroke (HR 0.77, 95% CI 0.67– 0.88), and peripheral artery disease (HR 0.66, 95% CI 0.63– 0.69) than the DPP-4i group. However, no significant difference was observed in the incidence of myocardial infarction (HR 1.06, 95% CI 0.87– 1.28) or LLEs (HR 1.05, 95% CI 0.80– 1.38) between the two groups. Conclusion: In this nationwide, real-world study, SGLT2i use demonstrated a neutral effect on LLEs compared to DPP-4i in patients with type 2 diabetes. However, SGLT2i was associated with a lower risk of all-cause mortality, heart failure, ischemic stroke, and peripheral artery disease. These findings contribute to the ongoing debate on the safety of SGLT2i regarding LLEs and highlight their broader CV benefits, warranting further investigation into their long-term effects on lower limb complications.