CONTEXT: There is evidence of both hypothalamic-pituitary-adrenocortical (HPA) axis and cognitive dysfunction in type 2 diabetes mellitus (T2DM). However, the exact nature and the associations between these abnormalities remain unclear. OBJECTIVES: The aim of the study was to characterize the nature of the HPA dysregulation in T2DM and ascertain whether impaired cognition in T2DM could be attributed to these abnormalities. DESIGN: A cross-sectional study was performed, contrasting matched groups on HPA axis function and cognition by using the combined dexamethasone (DEX)/CRH test and a neuropsychological battery assessing declarative and working memory, attention, and executive function. SETTING: The study was conducted in a research clinic in an academic medical center. PARTICIPANTS: Participants were volunteers functioning in the cognitively normal range. We studied 30 middle-aged individuals with T2DM, on average 7.5 yr since diabetes diagnosis, and 30 age-, gender-, and education-matched controls. MAIN OUTCOME MEASURES: Basal cortisol levels, cortisol levels during the DEX/CRH test, and performance on neuropsychological tests were measured. RESULTS: Individuals with T2DM had elevated basal plasma cortisol levels, higher levels after DEX suppression, and a larger response to CRH (all P <or= 0.005). Among individuals with T2DM, cortisol levels during the DEX/CRH test were positively associated with glycosylated hemoglobin (P = 0.05), independent of age, body mass index, hypertension, and dyslipidemia. Diabetic subjects showed cognitive impairments restricted to declarative memory. Across all subjects, declarative memory was inversely associated with cortisol levels; however, these associations were subsumed by glycemic control (glycosylated hemoglobin). CONCLUSIONS: HPA hyperactivity and declarative memory deficits are present in T2DM. Both alterations may reflect the negative impact of poor glycemic control on the hippocampal formation.
CONTEXT: There is evidence of both hypothalamic-pituitary-adrenocortical (HPA) axis and cognitive dysfunction in type 2 diabetes mellitus (T2DM). However, the exact nature and the associations between these abnormalities remain unclear. OBJECTIVES: The aim of the study was to characterize the nature of the HPA dysregulation in T2DM and ascertain whether impaired cognition in T2DM could be attributed to these abnormalities. DESIGN: A cross-sectional study was performed, contrasting matched groups on HPA axis function and cognition by using the combined dexamethasone (DEX)/CRH test and a neuropsychological battery assessing declarative and working memory, attention, and executive function. SETTING: The study was conducted in a research clinic in an academic medical center. PARTICIPANTS: Participants were volunteers functioning in the cognitively normal range. We studied 30 middle-aged individuals with T2DM, on average 7.5 yr since diabetes diagnosis, and 30 age-, gender-, and education-matched controls. MAIN OUTCOME MEASURES: Basal cortisol levels, cortisol levels during the DEX/CRH test, and performance on neuropsychological tests were measured. RESULTS: Individuals with T2DM had elevated basal plasma cortisol levels, higher levels after DEX suppression, and a larger response to CRH (all P <or= 0.005). Among individuals with T2DM, cortisol levels during the DEX/CRH test were positively associated with glycosylated hemoglobin (P = 0.05), independent of age, body mass index, hypertension, and dyslipidemia. Diabetic subjects showed cognitive impairments restricted to declarative memory. Across all subjects, declarative memory was inversely associated with cortisol levels; however, these associations were subsumed by glycemic control (glycosylated hemoglobin). CONCLUSIONS:HPA hyperactivity and declarative memory deficits are present in T2DM. Both alterations may reflect the negative impact of poor glycemic control on the hippocampal formation.
Authors: Shivam Champaneri; Gary S Wand; Saurabh S Malhotra; Sarah S Casagrande; Sherita Hill Golden Journal: Curr Diab Rep Date: 2010-12 Impact factor: 4.810
Authors: Christopher M Celano; Eleanor E Beale; Shannon V Moore; Deborah J Wexler; Jeff C Huffman Journal: Curr Diab Rep Date: 2013-12 Impact factor: 4.810
Authors: Po Lai Yau; David Javier; Wai Tsui; Victoria Sweat; Hannah Bruehl; Joan C Borod; Antonio Convit Journal: Psychiatry Res Date: 2009-11-10 Impact factor: 3.222
Authors: Rebecca M Reynolds; Mark W J Strachan; Javier Labad; Amanda J Lee; Brian M Frier; F Gerald Fowkes; Rory Mitchell; Jonathan R Seckl; Ian J Deary; Brian R Walker; Jackie F Price Journal: Diabetes Care Date: 2010-01-22 Impact factor: 17.152