Body Mass Index and Mild Cognitive Impairment Among Middle-Aged and Older Adults from Low- and Middle-Income Countries

Article type: Research Article

Authors: Smith, Lee^a | Shin, Jae Il^b | Oh, Hans^c | Carmichael, Christina^a | Jacob, Louis^{d; e} | Stefanac, Sinisa^f | Lindsay, Rosie K.^{g; *} | Soysal, Pinar^h | Veronese, Nicolaⁱ | Tully, Mark A.^j | Butler, Laurie^a | Barnett, Yvonne^a | Koyanagi, Ai^{d; k}

Affiliations: [a] Centre for Health, Performance and Wellbeing, Anglia Ruskin University, Cambridge, UK | [b] Department of Pediatrics, Yonsei University College of Medicine, Seoul, South Korea | [c] Suzanne Dworak Peck School of Social Work, University of Southern California, Los Angeles, CA, USA | [d] Research and Development Unit, Parc Sanitari Sant Joan de Déu, CIBERSAM, Dr.Antoni Pujadas, Barcelona, Spain | [e] Faculty of Medicine, University of Versailles Saint-Quentin-en-Yvelines, Montigny-le-Bretonneux, France | [f] Institute of Outcomes Research, Centre for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria | [g] Vision and Hearing Sciences, Anglia Ruskin University, Cambridge, UK | [h] Department of Geriatric Medicine, Faculty of Medicine, Bezmialem Vakif University, Fatih, İstanbul, Turkey | [i] Geriatric Unit, Department of Internal Medicine and Geriatrics, University of Palermo, Palermo, Italy | [j] School of Health Sciences, Institute of Mental Health Sciences, Ulster University, Newtownabbey, Northern Ireland | [k] ICREA, Pg, Barcelona, Spain

Correspondence: [*] Correspondence to: Rosie K. Lindsay, Vision and Hearing Sciences, Anglia Ruskin University, Cambridge, UK. E-mail: rkl109@pgr.aru.ac.uk.

Abstract: Background: The effect of weight modification on future dementia risk is currently a subject of debate and may be modified by age. Objective: The aim of the present study was to investigate the association between body mass index (BMI) status with mild cognitive impairment (MCI) (a preclinical stage of dementia) in middle-aged and older adults residing in six low- and middle-income countries using nationally representative data. Methods: Cross-sectional data from the Study on Global Ageing and Adult Health (SAGE) were analyzed. MCI was defined using the National Institute on Aging-Alzheimer’s Association criteria. BMI (kg/m2) was based on measured weight and height and categorized as: underweight (<18.5), normal (18.5–24.9), overweight (25.0–29.9), and obese (≥30.0). Multivariable logistic regression analysis and meta-analysis were conducted to assess associations. Results: Data on 32,715 individuals aged ≥50 years with preservation in functional abilities were analyzed [mean (SD) age 62.1 (15.6) years; 51.7% females]. Among those aged 50–64 years, compared to normal weight, underweight (OR = 1.44; 95% CI = 1.14–1.81), overweight (OR = 1.17; 95% CI = 1.002–1.37), and obesity (OR = 1.46; 95% CI = 1.09–1.94) were all significantly associated with higher odds for MCI. In those aged ≥65 years, underweight (OR = 0.71; 95% CI = 0.54–0.95) and overweight (OR = 0.72; 95% CI = 0.55–0.94) were associated with significantly lower odds for MCI, while obesity was not significantly associated with MCI. Conclusion: The results of the study suggest that the association between BMI and MCI is likely moderated by age. Future longitudinal studies are required to confirm or refute the present findings before recommendations for policy and practice can be made.

Keywords: Aged, body mass index, cognitive dysfunction, obesity

DOI: 10.3233/JAD-215345

Journal: Journal of Alzheimer's Disease, vol. 85, no. 3, pp. 1095-1105, 2022