Antibodies to Human Herpesviruses and Rate of Incident Cardiovascular Events and All-Cause Mortality in the UK Biobank Infectious Disease Pilot Study.

Background: Associations between human herpesviruses (HHVs) and cardiovascular disease/mortality have been reported, but evidence is inconsistent. We investigated associations between 3 common herpesviruses and (1) incident stroke or myocardial infarction (MI) and (2) all-cause mortality. Methods: We included participants from the UK Biobank Infectious Disease pilot study with valid serum antibody (IgG) measurements taken at cohort entry (2006-2010) for herpes simplex virus type 1 (HSV1), varicella zoster virus (VZV), and cytomegalovirus (CMV). Linked hospital and mortality records up to December 30 2019 provided information on rates of (1) incident first stroke or MI and (2) all-cause mortality. Hazard ratios (HRs) from Cox proportional hazards regression models were used to assess relationships between (1) HHV seropositivity, (2) HHV titer and incident stroke/MI, and death outcomes. Fully adjusted models accounted for sociodemographic information (age, sex, ethnicity, education, deprivation quintile, birthplace, population density), baseline comorbidities (including diabetes and hypertension), smoking status, body mass index, and serum cholesterol. Results: Of 9429 study participants (56% female, 95% White, median age 58 years), 41% were seropositive for all 3 HHVs. Human herpesvirus seropositivity was not associated with stroke/MI (fully adjusted HRs and 95% confidence intervals [CIs]: HSV1 = 0.93 [CI, 0.72-1.22], VZV = 0.78 [CI, 0.51-1.20], CMV = 0.91 [CI, 0.71-1.16]) or all-cause mortality (HSV1 = 1.21 [CI, 1.00-1.47], VZV = 0.79 [CI, 0.58-1.07], CMV = 0.90 [CI, 0.76-1.06]). Human herpesvirus titers were not associated with outcomes. Conclusions: In this mostly White UK Biobank subset, neither HHV seropositivity nor titers were associated with stroke/MI or all-cause mortality.

Anticoagulant prescribing for atrial fibrillation and risk of incident dementia.

OBJECTIVE: The aim of this study was to investigate the association between oral anticoagulant type (direct oral anticoagulants (DOACs) vs vitamin K antagonists (VKAs)) and incident dementia or mild cognitive impairment (MCI) among patients with newly diagnosed atrial fibrillation (AF). METHODS: Using linked electronic health record (EHR) data from the Clinical Practice Research Datalink in the UK, we conducted a historical cohort study among first-time oral anticoagulant users with incident non-valvular AF diagnosed from 2012 to 2018. We compared the incidence of (1) clinically coded dementia and (2) MCI between patients prescribed VKAs and DOACs using Cox proportional hazards regression models, with age as the underlying timescale, accounting for calendar time and time on treatment, sociodemographic and lifestyle factors, clinical comorbidities and medications. RESULTS: Of 39 200 first-time oral anticoagulant users (44.6% female, median age 76 years, IQR 68-83), 20 687 (53%) were prescribed a VKA and 18 513 (47%) a DOAC at baseline. Overall, 1258 patients (3.2%) had GP-recorded incident dementia, incidence rate 16.5 per 1000 person-years. DOAC treatment for AF was associated with a 16% reduction in dementia diagnosis compared with VKA treatment in the whole cohort (adjusted HR 0.84, 95% CI: 0.73 to 0.98) and with a 26% reduction in incident MCI (adjusted HR 0.74, 95% CI: 0.65 to 0.84). Findings were similar across various sensitivity analyses. CONCLUSIONS: Incident EHR-recorded dementia and MCI were less common among patients prescribed DOACs for new AF compared with those prescribed VKAs.

Ethnic Differences in Dementia Risk: A Systematic Review and Meta-Analysis.

BACKGROUND: Globally around 50 million people have dementia. Risk factors for dementia such as hypertension and diabetes are more common in Black, Asian, and other ethnic minorities. There are also marked ethnic inequalities in care seeking, likelihood of diagnosis, and uptake of treatments for dementia. Nevertheless, ethnic differences in dementia incidence and prevalence remain under-explored. OBJECTIVE: To examine published peer-reviewed observational studies comparing age-specific or age-adjusted incidence or prevalence rates of dementia between at least two ethnic groups. METHODS: We searched seven databases on 1 September 2019 using search terms for ethnicity, dementia, and incidence or prevalence. We included population-based studies comparing incidence or prevalence of dementia after accounting for age of at least two ethnic groups in adults aged 18 or more. Meta-analysis was conducted for eligible ethnic comparisons. RESULTS: We included 12 cohort studies and seven cross-sectional studies. Thirteen were from the US, and two studies each from the UK, Singapore, and Xinjiang Uyghur Autonomous Region in China. The pooled risk ratio for dementia incidence obtained from four studies comparing Black and White ethnic groups was 1.33 (95% CI 1.07-1.65; I-squared = 58.0%). The pooled risk ratio for dementia incidence comparing the Asian and White ethnic groups was 0.86 (95% CI 0.728-1.01; I-squared = 43.9%). There was no difference in the incidence of dementia for Latino ethnic group compared to the White ethnic group. CONCLUSION: Evidence to date suggest there are ethnic differences in risk of dementia. Better understanding of the drivers of these differences may inform efforts to prevent or treat dementia.