Influenza vaccination uptake and factors influencing vaccination decision among patients with chronic kidney or liver disease.

INTRODUCTION: Seasonal influenza is a major global health problem causing substantial morbidity and health care costs. Yet, in many countries, the rates of influenza vaccination remain low. Chronic kidney or liver diseases (CKLD) predispose patients to severe influenza infections, but data on vaccination acceptance and status is limited in this risk population. We investigated the influenza vaccination awareness considering sociodemographic factors in CKLD patients. PATIENTS AND METHODS: This cross-sectional, questionnaire-based study recruited CKLD patients managed at three Viennese tertiary care centers between July and October 2020. CKLD was defined as chronic kidney- (all stages) or compensated/decompensated liver disease, including kidney/liver transplant recipients. Questionnaires assessed sociodemographic and transplant- associated parameters, patients vaccination status and the individuals self-perceived risks of infection and associated complications. RESULTS: In total 516 patients (38.1% female, mean age 56.4 years) were included. 43.9% of patients declared their willingness to be vaccinated in the winter season 2020/2021, compared to 25.4% in 2019/2020 and 27.3% in 2016-2018. Vaccination uptake was associated with the self-perceived risks of infection (OR: 2.8 (95%CI: 1.8-4.5), p<0.001) and associated complications (OR: 3.8 (95%CI: 2.3-6.3), p<0.001) as well as with previously received influenza vaccination (2019/2020: OR 17.1 (95%CI: 9.5-30.7), p<0.001; season 2016-2018: OR 8.9 (95%CI: 5.5-14.5), p<0.001). Most frequent reasons for not planning vaccination were fear of a) graft injury (33.3%), b) complications after vaccination (32.4%) and c) vaccine inefficiency (15.0%). CONCLUSION: While influenza vaccination willingness in patients with CKLD is increasing in the 2020/2021 season, vaccination rates may still remain <50%. Novel co-operations with primary health care, active vaccination surveillance and financial reimbursement may substantially improve vaccination rates in high-risk CKLD patients.

The bradycardic agent ivabradine decreases conduction velocity in the AV node and in the ventricles in-vivo.

Ivabradine blocks hyperpolarisation-activated cyclic nucleotide-gated (HCN) channels, thereby lowering the heart rate, an action that is used clinically for the treatment of heart failure and angina pectoris. We and others have shown previously that ivabradine, in addition to its HCN channel blocking activity, also inhibits voltage-gated Na channels in vitro at concentrations that may be clinically relevant. Such action may reduce conduction velocity in cardiac atria and ventricles. Here, we explore the effect of administration of ivabradine on parameters of ventricular conduction and repolarization in the surface ECG of anesthetized mice. We found that 5 min after i.p. administration of 10 mg/kg ivabradine spontaneous heart rate had declined by ~13%, which is within the range observed in human clinical studies. At the same time a significant increase in QRS duration by ~18% was observed, suggesting a reduction in ventricular conduction velocity. During transesophageal pacing at heart rates between 100 and 220 beats/min there was no obvious rate-dependence of ivabradine-induced QRS prolongation. On the other hand, ivabradine produced substantial rate-dependent slowing of AV nodal conduction. We conclude that ivabradine prolongs conduction in the AV-node and in the ventricles in vivo.