Heart failure after dengue infection- a population-based self-controlled case-series study.

BACKGROUND: Major cardiovascular events (MACEs) have been described with dengue infection. Among these MACEs, heart failure (HF) is the most common but has not been thoroughly assessed. This study aimed to evaluate the association between dengue and HF. METHODS: Under the self-controlled case-series study design, we used the Notifiable Infectious Disease dataset linkage with the National Health Insurance claims data to obtain the study subjects. All laboratory-confirmed dengue cases who were hospitalized for HF after dengue infection within one year between 2009 and 2015 in Taiwan were included. We identified the first 7 and 14 days after dengue infection as the risk intervals. The incidence rate ratio (IRR) and 95% confidence interval (CI) for HF were estimated by conditional Poisson regression. RESULTS: Among the 65,906 dengue patients, 230 had admission for HF after dengue infection within one year. The IRR of HF admission within the first week after dengue infection was 56.50 (95% C.I. 43.88-72.75). This risk was highest in >60 years (IRR = 59.32, 95% C.I. 45.43-77.43) and lower in 0-40 years (IRR = 25.82, 95% C.I. 2.89-231.02). The risk was nearly nine times higher among admission (for dengue infection) than among nonadmission cases (IRR 75.35 vs. 8.61, p < 0.0001). The risks increased slightly in the second week 8.55 and became less obvious after the third and fourth week. CONCLUSIONS: Patients with dengue infection have a risk of developing acute heart failure within one week, especially in >60 years, men, and dengue admission subjects. The findings emphasize the awareness of diagnosis and further appropriate treatment of HF.

The Incidence of Myocarditis Following an Influenza Vaccination: A Population-Based Observational Study.

BACKGROUND AND OBJECTIVE: Recently, studies have pointed to a link between coronavirus disease 2019 vaccinations and myocarditis. Myocarditis following an influenza vaccine has been sporadically reported. However, it is not known whether this adverse event occurs among elderly individuals who have received influenza vaccines. We used a population-based database and a self-controlled case-series design to estimate the incidence of myocarditis following an influenza vaccination. METHODS: Data were extracted from Taiwan's National Health Insurance Research Database. The study population consisted of elderly people aged ≥ 65 years who had de novo myocarditis, which required hospitalization, within 6 months after receiving an influenza vaccination between 2003 and 2017. The first 1-7, 1-14, and 1-42 days after vaccination were defined as risk intervals, and the other periods were defined as control intervals. Poisson regression was used to calculate the incidence rate ratio for myocarditis between the risk and control periods. RESULTS: Within 180 days following a vaccination, 191 people were hospitalized for myocarditis among 19,678,904 people. In comparison with control intervals, the incidence rate ratios of an admission for myocarditis for days 1-7, 1-14, and 1-42 were 0.80 (95% confidence interval 0.36-1.81), 0.72 (95% confidence interval 0.39-1.32), and 0.73 (95% confidence interval 0.50-1.05), respectively. Subgroup analyses by sex, age, Charlson Comorbidity Index scores, and comorbidities did not yield significant differences in the incidence rate ratio. CONCLUSIONS: Regardless of the post-vaccination time and underlying baseline characteristics, the incidence risk of myocarditis is not significantly increased in the elderly following an influenza vaccination.

Major acute cardiovascular events after dengue infection-A population-based observational study.

BACKGROUND: Dengue virus (DENV) infection may be associated with increased risks of major adverse cardiovascular effect (MACE), but a large-scale study evaluating the association between DENV infection and MACEs is still lacking. METHODS AND FINDINGS: All laboratory confirmed dengue cases in Taiwan during 2009 and 2015 were included by CDC notifiable database. The self-controlled case-series design was used to evaluate the association between DENV infection and MACE (including acute myocardial infarction [AMI], heart failure and stroke). The "risk interval" was defined as the first 7 days after the diagnosis of DENV infection and the "control interval" as 1 year before and 1 year after the risk interval. The incidence rate ratio (IRR) and 95% confidence interval (CI) for MACE were estimated by conditional Poisson regression. Finally, the primary outcome of the incidence of MACEs within one year of dengue was observed in 1,247 patients. The IRR of MACEs was 17.9 (95% CI 15.80-20.37) during the first week after the onset of DENV infection observed from 1,244 eligible patients. IRR were significantly higher for hemorrhagic stroke (10.9, 95% CI 6.80-17.49), ischemic stroke (15.56, 95% CI 12.44-19.47), AMI (13.53, 95% CI 10.13-18.06), and heart failure (27.24, 95% CI 22.67-32.73). No increased IRR was observed after day 14. CONCLUSIONS: The risks for MACEs are significantly higher in the immediate time period after dengue infection. Since dengue infection is potentially preventable by early recognition and vaccination, the dengue-associated MACE should be taken into consideration when making public health management policies.