Obesity Measures in Relation to Cognition in the Northern Manhattan Study

Article type: Research Article

Authors: Gardener, Hannah^{a; *} | Caunca, Michelle^a | Dong, Chuanhui^a | Cheung, Ying Kuen^b | Rundek, Tatjana^a | Elkind, Mitchell S.V.^c | Wright, Clinton B.^d | Sacco, Ralph L.^a

Affiliations: [a] Department of Neurology, University of Miami, Miller School of Medicine, Miami, FL, USA | [b] Department of Biostatistics, Mailman Public School of Health, Columbia University, New York, NY, USA | [c] Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA | [d] National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA

Correspondence: [*] Correspondence to: Hannah Gardener, ScD, Department of Neurology, Miller School of Medicine, University of Miami, Clinical Research Building, 1120 NW 14th Street, Miami, FL 33136, USA. Tel.: +1 305 243 9283; Fax: +1 305 243 7801; hgardener@med.miami.edu

Abstract: Background:Mid-life obesity is associated with cognitive impairment, though the relationship for late-life obesity is equivocal, and may depend on the anthropometric measure. Objective:We examined the relationship between adiposity and cognition across age categories, cognitive domains, and by measures of obesity in a multi-ethnic population-based cohort. Methods:The study included 1,179 Northern Manhattan Study participants with obesity measures at baseline (44% overweight, 30% obese), an initial neuropsychological assessment conducted within 7 years (mean age = 70), and a second cognitive assessment conducted on average 6 years later. Z-scores were derived for cognitive domains (episodic and semantic memory, executive function, processing speed) and averaged to calculate global cognition. Body mass index (BMI) and waist:hip ratio (WHR) were examined in relation to cognitive performance and change over time, stratified by age, using linear regression models adjusting for vascular risk factors. Results:Among those age<65 years at baseline, greater WHR was associated with worse global cognitive performance at initial assessment and directly associated with decline in performance between assessments. The association with initial performance was strongest for non-Hispanic Whites (beta = –0.155/standard deviation, p = 0.04), followed by non-Hispanic Black/African Americans (beta = –0.079/standard deviation, p = 0.07), and Hispanics (beta = –0.055/standard deviation, p = 0.03). The associations were most apparent for the domains of processing speed and executive function. There was no association for BMI among those <65 years. Among those age ≥65, there was no association for BMI or WHR with cognitive performance at initial assessment nor decline over time. Conclusion:Our results support the detrimental effect of mid-life rather than later life obesity, particularly abdominal adiposity, on cognitive impairment and decline.

Keywords: Adiposity, cognition, cognitive dysfunction, epidemiology, obesity

DOI: 10.3233/JAD-201071

Journal: Journal of Alzheimer's Disease, vol. 78, no. 4, pp. 1653-1660, 2020