Timothy L Wiemken1, Joanne Salas2, Daniel F Hoft3, Christine Jacobs4, John E Morley5, Jeffrey F Scherrer2. 1. Saint Louis University, School of Medicine, Department of Internal Medicine, Division of Infectious Diseases, Allergy, and Immunology, Saint Louis, MO, United States; The Advanced HEAlth Data (AHEAD) Research Institute, Saint Louis University, School of Medicine, 1402 South Grand Blvd, St. Louis, MO, United States. Electronic address: timothy.wiemken@health.slu.edu. 2. Department of Family and Community Medicine, Saint Louis University, School of Medicine, 1402 South Grand Blvd, St. Louis, MO, United States; Harry S. Truman Veterans Administration Medical Center, Columbia, MO, United States; The Advanced HEAlth Data (AHEAD) Research Institute, Saint Louis University, School of Medicine, 1402 South Grand Blvd, St. Louis, MO, United States. 3. Saint Louis University, School of Medicine, Department of Internal Medicine, Division of Infectious Diseases, Allergy, and Immunology, Saint Louis, MO, United States; Saint Louis University, Department of Molecular Microbiology & Immunology, Saint Louis, MO, United States. 4. Department of Family and Community Medicine, Saint Louis University, School of Medicine, 1402 South Grand Blvd, St. Louis, MO, United States. 5. Saint Louis University, School of Medicine, Department of Internal Medicine, Division of Geriatric Medicine, 1402 South Grand Blvd, St. Louis, MO, United States.
Abstract
BACKGROUND: Two Taiwan based studies indicated influenza vaccinations are associated with lower risk for dementia in patient cohorts with chronic disease. We determined if such associations exist in a large, nationally distributed sample of U.S. patients not selected for chronic disease. METHODS: Data was obtained from Veterans Health Administration medical records (9/1/2009 - 8/31/19). Eligible patients were ≥65 years of age and free of dementia for two years prior to enrollment through the end of the first influenza season (9/1/2009 to 3/1/2012). Competing risk models estimated the risk of dementia in those with influenza vaccination (n = 66,822) compared to those without vaccination (n = 56,925). Propensity scores and inverse probability of treatment weighting controlled for confounding. RESULTS: On average, patients were 75.5 (±7.3) years of age, 3.8% were female and 91.6% were white race. After controlling for confounding, patients with influenza vaccination were significantly less likely to develop dementia compared to patients without vaccination (HR = 0.86; 95 %CI:0.83-0.88). Patients with 1, 2 or 3-5 vaccines vs. none had similar risks for dementia and patients with ≥ 6 influenza vaccines vs. none had a significant lower risk for dementia (HR = 0.88, 95 %CI: 0.83-0.94). CONCLUSIONS: Repeated receipt of influenza vaccinations, compared to remaining unvaccinated, is associated with lower risk for dementia. This is consistent with the hypotheses that vaccinations may reduce risk of dementia by training the immune system and not by preventing specific infectious disease. If vaccines are identified as causative factors in reducing incident dementia, they offer an inexpensive, low-risk intervention with effects greater than any existing preventive measure.
BACKGROUND: Two Taiwan based studies indicated influenza vaccinations are associated with lower risk for dementia in patient cohorts with chronic disease. We determined if such associations exist in a large, nationally distributed sample of U.S. patients not selected for chronic disease. METHODS: Data was obtained from Veterans Health Administration medical records (9/1/2009 - 8/31/19). Eligible patients were ≥65 years of age and free of dementia for two years prior to enrollment through the end of the first influenza season (9/1/2009 to 3/1/2012). Competing risk models estimated the risk of dementia in those with influenza vaccination (n = 66,822) compared to those without vaccination (n = 56,925). Propensity scores and inverse probability of treatment weighting controlled for confounding. RESULTS: On average, patients were 75.5 (±7.3) years of age, 3.8% were female and 91.6% were white race. After controlling for confounding, patients with influenza vaccination were significantly less likely to develop dementia compared to patients without vaccination (HR = 0.86; 95 %CI:0.83-0.88). Patients with 1, 2 or 3-5 vaccines vs. none had similar risks for dementia and patients with ≥ 6 influenza vaccines vs. none had a significant lower risk for dementia (HR = 0.88, 95 %CI: 0.83-0.94). CONCLUSIONS: Repeated receipt of influenza vaccinations, compared to remaining unvaccinated, is associated with lower risk for dementia. This is consistent with the hypotheses that vaccinations may reduce risk of dementia by training the immune system and not by preventing specific infectious disease. If vaccines are identified as causative factors in reducing incident dementia, they offer an inexpensive, low-risk intervention with effects greater than any existing preventive measure.
Authors: Timothy L Wiemken; Joanne Salas; John E Morley; Daniel F Hoft; Christine Jacobs; Jeffrey F Scherrer Journal: J Am Geriatr Soc Date: 2021-12-12 Impact factor: 7.538
Authors: Avram S Bukhbinder; Yaobin Ling; Omar Hasan; Xiaoqian Jiang; Yejin Kim; Kamal N Phelps; Rosemarie E Schmandt; Albert Amran; Ryan Coburn; Srivathsan Ramesh; Qian Xiao; Paul E Schulz Journal: J Alzheimers Dis Date: 2022 Impact factor: 4.160