Albuminuria and Cognitive Decline in People with Diabetes and Normal Renal Function

Abstract

SummaryBackground and objectives Diabetes mellitus is associated with increased risk of cognitive impairment. This study examines whether microvascular disease, as measured by albuminuria and decline in estimated GFR (eGFR), is associated with cognitive decline during 3.3 years of follow-up in individuals with diabetes with a normal baseline eGFR (approximately 90 ml/min per 1.73 m 2 ). Mixed-effects models were used to assess the association of albuminuria and eGFR on the percentage decline in each test.Results Participants with albuminuria at baseline and follow-up (persistent albuminuria) (25.8% [95% confidence interval (CI), 27.3 to 24.2]) and participants with albuminuria at follow-up but none at baseline (progressive albuminuria) (24.1% [95% CI, 25.6 to 22.7]) had greater percentage declines on information processing speed than participants without albuminuria at baseline and at follow-up (no albuminuria) (22.6% [95% CI, 23.4 to 21.9]) (P=0.001 and P=0.10, respectively). There were borderline percentage changes in the test of verbal memory (4.8% [95% CI, 2.4 to 7.1] and 4.7% [95% CI, 2.5 to 7.0] versus 7.1% [95% CI, 6.0 to 8.3]; P=0.11 and P=0.08, respectively). On logistic regression analysis, persistent albuminuria (odds ratio, 1.37 [95% CI, 1.09 to 1.72]) and progressive albuminuria (odds ratio, 1.25 [95% CI, 1.02 to 1.56]) were associated with a $5% decline in information processing speed scores but not with verbal memory or executive function performance. A 1 ml/min per 1.73 m 2 per year eGFR decline had a borderline association with decline in tests of cognitive function.Conclusions Persistent albuminuria and progressive albuminuria are associated with a decline in cognitive function in relatively young individuals with diabetes with unimpaired eGFR. These findings do not rule out the possibility of other processes causing cognitive decline.

Cognitive decline in newly diagnosed Type 2 Diabetes and the effect of good glycemic control on cognitive function

“…There are various other studies with higher prevalences ranging from 37% to 56.2%. (15,16) In addition our study had a significant statistical correlation (P=0.002) between Diabetic Nephropathy and cognitive decline in Type2 diabetics as evidenced by MMSE scores. This is in accordance with the study by Barzilay et al where the presence of albuminuria in Diabetics correlated with greater declines in information processing speed and memory(P=0.001).…”

Estimated Glomerular Filtration Rate is not Associated with Alzheimer’s Disease in a Northern Ireland Cohort

“…In addition, other studies also reported significant associations between renal impairment characterised by the presence of microalbuminuria and cognitive impairment [10,20,21,31]. A recent meta-analysis of five population based prospective studies included 27,805 participants, demonstrated a non-significant increased risk of cognitive impairment or dementia in those with an eGFR < 60 ml/min/1.73m 2 , with a significant association found only in those with albuminuria [7].…”

“…The global prevalence of CKD is estimated at 11-13%, increasing with age to almost 28% in those 70 years or older [8]. Both the kidneys and brain are susceptible to vascular damage with similar haemodynamic and physiological characteristics and risk factors that include diabetes mellitus, hypertension and hyperlipidemia [9,10]. Renal dysfunction also accelerates vascular ageing and calcification, including the vasculature proximal to the brain, such as the circle of Willis [11], manifesting in structural alterations and increased risk of cerebrovascular disease [12].…”

Associations of Early Kidney Disease With Brain Magnetic Resonance Imaging and Cognitive Function in African Americans With Type 2 Diabetes Mellitus

“…Diabetes, blood pressure, and lipid control were similar to those in participants from contemporary cohorts in other racial/ethnic groups, reducing the risk of bias of healthcare access on relationships. 12, 33 …”

“…ACCORD MIND was an ancillary study that assessed the effects of blood sugar, blood pressure, and lipid lowering on cognitive function. 11, 12 Detailed recruitment strategies have been reported for both studies. 11–14 Medication, medical and education histories were collected and body mass index (BMI) and blood pressure recorded in all participants.…”