MP311INFLUENZA VACCINATION REDUCES DEMENTIA RISK IN CHRONIC KIDNEY DISEASE PATIENTS VACCINATION REDUCES DEMENTIA RISK IN CHRONIC KIDNEY DISEASE PATIENTS: A POPULATION-BASED COHORT STUDY

Abstract

Introduction and Aims: Taiwan has the highest prevalence of chronic kidney disease (CKD) worldwide. CKD, a manifestation of vascular diseases, is associated with a high risk of dementia. In this study, we estimated the association of influenza vaccination with dementia risk in CKD patients. Method(s): This study used data from the National Health Insurance Research Database of Taiwan. The study cohort comprised all patients who were diagnosed with CKD at health care facilities in Taiwan (International Classification of Disease, Ninth Revision, Clinical Modification) over an 8-year period (n = 32,844) from January 1, 2000, to December 31, 2007. Each patient was followed up for dementia risk or protective factors: demographic characteristics of age and sex; comorbidities of diabetes, hypertension, dyslipidemia, cerebrovascular diseases, parkinsonism, epilepsy, substance and alcohol use disorders, mood disorder, anxiety disorder, psychotic disorder, and sleep disorder; level of urbanization; monthly income; and statin, metformin, aspirin, and angiotensin-converting enzyme inhibitor (ACEI) use. A propensity score was derived using a logistic regression model to estimate the effect of vaccination by accounting for covariates that predict receiving the intervention (vaccine). A time-dependent Cox proportional hazard model was used to calculate the hazard ratios (HRs) of dementia among vaccinated and unvaccinated CKD patients. Result(s): The eligible study population consisted of 11,943 individuals in the CKD cohort; 5,745 (48%) CKD patients received influenza vaccination; the remaining 6,198 patients (52%) received no influenza vaccination. The adjusted HRs (aHRs) of dementia decreased in vaccinated patients compared with those in unvaccinated patients (respectively, for influenza season, noninfluenza season, and all seasons: aHRs = 0.68, 0.58, and 0.64; p < 0.0001, p < 0.0001, and p < 0.0001). In the sensitivity analysis, adjustments were made to estimate the association of age; sex; diabetes; dyslipidemia; hypertension; cerebrovascular diseases; anxiety disorder; and statin, metformin, ACEI, and aspirin use with the incidence of dementia in different models. A stronger protective effect against dementia risk was demonstrated in noninfluenza seasons. Regardless of comorbidities or drug use, influenza vaccination is an independent protective factor and dose dependently reduced dementia risk in CKD patients. Conclusion(s): Influenza vaccination exerts dose-response and synergistic protective effects against dementia in CKD patients with dementia risk factors by reducing the incidence of dementia.