The Look AHEAD (Action for Health in Diabetes) study was designed to test whether weight loss improved cardiovascular morbidity and mortality in patients with type 2 diabetes. The study was a multicenter, randomized clinical trial that examined the long-term effects of an intensive lifestyle intervention program designed to achieve and maintain weight loss by decreased caloric intake and increased physical activity. Three ancillary studies assessed neuroimaging and cognitive testing outcomes many years after the lifestyle intervention. These studies have found that the legacy effects of the lifestyle intervention on the brain are heterogeneous, with suggestions of benefits in some groups of participants and even harms in some other groups. Look AHEAD continues to increase understanding of mechanisms of long-term lifestyle intervention effects on the brain through ancillary studies such as a study of intervention effects on the renin angiotensin system (RAS).
Publications:
Hayden, K. M., M. M. Mielke, J. K. Evans, R. Neiberg, D. Molina-Henry, M. Culkin, S. Marcovina, K. C. Johnson, O.T. Carmichael, S. R. Rapp, B. C. Sachs, J. Ding, H. Shappell, L. Wagenknecht, J. A. Luchsinger, and M. A. Espeland. "Association between Modifiable Risk Factors and Levels of Blood-Based Biomarkers of Alzheimer's and Related Dementias in the Look Ahead Cohort." JAR Life 13 (2024): 1-21.
Wharton W, Anderson A, Hayden KM, Carmichael O, Clark JM, Luchsinger JA, Espeland M, Yasar S. Effect of renin-angiotensin system antihypertensive medication use on cognitive function in diabetes mellitus with obesity or overweight: An ancillary study to the action for health in diabetes (look ahead) trial. Diabetes Obes Metab. 2022;24(12):2443-53. PMCID: PMC9617758. PMID: 36065050.
Simpson FR, Carmichael O, Hayden KM, Hugenschmidt CE, McCaffery JM, Yasar S, Pajewski NM, Espeland MA, Indices for Accelerated Aging in O, Diabetes Ancillary Study of the Action for Health in Diabetes T. Does the impact of intensive lifestyle intervention on cognitive function vary depending baseline level of frailty? An ancillary study to the action for health in diabetes (look ahead) trial. J Diabetes Complications. 2021;35(5):107909. PMCID: PMC8046723. PMID: 33745805.
Carmichael OT, Neiberg RH, Dutton GR, Hayden KM, Horton E, Pi-Sunyer FX, Johnson KC, Rapp SR, Spira AP, Espeland MA. Long-term change in physiological markers and cognitive performance in type 2 diabetes: The Look AHEAD Study. J Clin Endocrinol Metab. 2020;105(12):e4778-e4791. PMID: 32845968. *This was a featured article selected by The Endocrine Society for a thematic Issue on Diabetes
Espeland MA, Hayden KM, Lockhart SN, Yassine HN, Hoscheidt S, Yasar S, Luchsinger JA, Neiberg RH, Brinton RD, Carmichael O, Action for Health in Diabetes Brain Magnetic Resonance Imaging Research G. Sex-related differences in brain volumes and cerebral blood flow among overweight and obese adults with type 2 diabetes: Exploratory analyses from the action for health in diabetes brain magnetic resonance imaging study. J Gerontol A Biol Sci Med Sci. 2019;75(4):771-778. PMCID: PMC7205422. PMID: 30997482.
Espeland MA, Dutton GR, Neiberg R, Carmichael O, Hayden K, Neiberg RH, Newman AB, Keller JN, Wadden TA, Rapp SR, Hill JO, Horton ES, Johnson KC, Wagenknecht L, Wing RR, Action for Health in Diabetes Brain Magnetic Resonance Imaging, Action for Health Movement, Memory Ancillary Study Research Groups. Long-term Impact of Weight Loss Intervention on Changes in Cognitive Function: Exploratory Analyses from the Action for Health in Diabetes Randomized Controlled Clinical Trial. Journals of Gerontology Series A: Biomedical Sciences and Medical Sciences. 2018 Mar; 73:484-491. PMCID: PMC5861893 PMID: 28958022.
Carmichael O, people name INFO
Grants:
R01 AG074258 NIH (NIA)
Effects of the renin angiotensin system on MRI volumetric measures and cognitive function in the Alzheimer's disease process: the LookAHEAD study
Major Goals: To evaluate the role of RAS proteins in aging and how it contributes to the development of AD using brain MRI imaging and cognitive measures in people with history of diabetes mellitus and obesity.
Role: Co-Investigator
