Erica Kornblith1,2, Amber Bahorik2,3, Yixia Li1,3, Carrie B Peltz1,3, Deborah E Barnes1,2,4, Kristine Yaffe1,2,3,4,5. 1. San Francisco Veterans Affairs Health Care System, San Francisco, California, USA. 2. Department of Psychiatry and Behavioral Sciences, University of California San Francisco USA. 3. Northern California Institute for Research and Education, San Francisco, California, USA. 4. Department of Epidemiology and Biostatistics, University of California San Francisco, USA. 5. Department of Neurology, University of California San Francisco, USA.
Abstract
OBJECTIVE: Traumatic brain injury (TBI) is associated with elevated rates of cardiovascular disease (CVD), and both CVD and TBI are risk factors for dementia. We investigated whether CVD and its risk factors underlie the association between TBI and dementia. MATERIALS AND METHODS: Cox proportional hazards models among 195,416 Veterans Health Administration patients age 55+ with TBI and a non-TBI, age/sex/race-matched comparison sample. RESULTS: Veterans +TBI were more likely to have any CVD diagnosis (24% vs 36% p = <0.001) or risk factor (83 vs. 90% p < .001) compared to -TBI. During follow-up (mean ~7 years), 12.0% of Veterans with TBI only (HR: 2.17 95% CI 2.09-2.25), and 10.3% with CVD only developed dementia (HR 1.21 95% CI 1.15-1.28), compared to 6.5% with neither. There was an additive association between TBI and CVD on dementia risk (HR 2.51, 95% CI 2.41-2.61). Among those +TBI (±CVD), risk was minimally attenuated by adjustment for CVD/CVD risk factors (unadjusted HR: 2.38, 95% CI: 2.31-2.45; adjusted HR: 2.17, 95% CI 2.10-2.23). CONCLUSIONS: Older veterans TBI have increased prevalence of CVD/CVD risk factors. TBI and CVD had an additive statistical association, with dementia risk increased by ~2.5-fold. However, CVD accounted for little of the association between TBI and dementia. More research is needed to understand mechanisms of TBI-dementia and inform clinical guidelines post-TBI.
OBJECTIVE: Traumatic brain injury (TBI) is associated with elevated rates of cardiovascular disease (CVD), and both CVD and TBI are risk factors for dementia. We investigated whether CVD and its risk factors underlie the association between TBI and dementia. MATERIALS AND METHODS: Cox proportional hazards models among 195,416 Veterans Health Administration patients age 55+ with TBI and a non-TBI, age/sex/race-matched comparison sample. RESULTS: Veterans +TBI were more likely to have any CVD diagnosis (24% vs 36% p = <0.001) or risk factor (83 vs. 90% p < .001) compared to -TBI. During follow-up (mean ~7 years), 12.0% of Veterans with TBI only (HR: 2.17 95% CI 2.09-2.25), and 10.3% with CVD only developed dementia (HR 1.21 95% CI 1.15-1.28), compared to 6.5% with neither. There was an additive association between TBI and CVD on dementia risk (HR 2.51, 95% CI 2.41-2.61). Among those +TBI (±CVD), risk was minimally attenuated by adjustment for CVD/CVD risk factors (unadjusted HR: 2.38, 95% CI: 2.31-2.45; adjusted HR: 2.17, 95% CI 2.10-2.23). CONCLUSIONS: Older veterans TBI have increased prevalence of CVD/CVD risk factors. TBI and CVD had an additive statistical association, with dementia risk increased by ~2.5-fold. However, CVD accounted for little of the association between TBI and dementia. More research is needed to understand mechanisms of TBI-dementia and inform clinical guidelines post-TBI.
Authors: Flora M Hammond; John D Corrigan; Jessica M Ketchum; James F Malec; Kristen Dams-OʼConnor; Tessa Hart; Thomas A Novack; Jennifer Bogner; Marie N Dahdah; Gale G Whiteneck Journal: J Head Trauma Rehabil Date: 2019 Jul/Aug Impact factor: 2.710
Authors: J A Mortimer; C M van Duijn; V Chandra; L Fratiglioni; A B Graves; A Heyman; A F Jorm; E Kokmen; K Kondo; W A Rocca Journal: Int J Epidemiol Date: 1991 Impact factor: 7.196