Effect of hypoglycemia on brain structure in people with type 2 diabetes: epidemiological analysis of the ACCORD-MIND MRI trial

Diabetes Care. 2014 Dec;37(12):3279-85. doi: 10.2337/dc14-0973. Epub 2014 Sep 29.

Abstract

Objective: The effect of hypoglycemia related to treatment of type 2 diabetes mellitus (T2DM) on brain structure remains unclear. We aimed to assess whether symptomatic severe hypoglycemia is associated with brain atrophy and/or white matter abnormalities.

Research design and methods: We included T2DM participants with brain MRI from the Action to Control Cardiovascular Risk in Diabetes-Memory in Diabetes (ACCORD-MIND) trial. Symptomatic severe hypoglycemia was defined as blood glucose <2.8 mmol/L or symptoms resolved with treatments that required the assistance of another person or medical assistance (hypoglycemia requiring assistance [HA]). Standardized brain MRI was performed at baseline and at 40 months. Total brain volume (TBV) and abnormal white matter (AWM) volume were calculated using an automated computer algorithm. Brain MRI scans of hypoglycemic participants were also reviewed for local disease.

Results: Of the 503 T2DM participants (mean age, 62 years) with successful baseline and 40-month brain MRI, 28 had at least one HA episode during the 40-month follow-up. Compared with participants without HA, those with HA had marginally significant less atrophy (less decrease in TBV) from baseline to 40 months (-9.55 [95% CI -15.21, -3.90] vs. -15.38 [95% CI -16.64, -14.12], P = 0.051), and no significant increase of AWM volume (2.06 [95% CI 1.71, 2.49] vs. 1.84 [95% CI 1.76, 1.91], P = 0.247). In addition, no unexpected local signal changes or volume loss were seen on hypoglycemic participants' brain MRI scans.

Conclusions: Our study suggests that hypoglycemia related to T2DM treatment may not accentuate brain pathology, specifically brain atrophy or white matter abnormalities.

Trial registration: ClinicalTrials.gov NCT00182910.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural

MeSH terms

  • Adult
  • Aged
  • Atrophy / chemically induced
  • Atrophy / epidemiology
  • Atrophy / pathology
  • Blood Glucose / drug effects
  • Brain / drug effects
  • Brain / pathology*
  • Brain / physiology
  • Cardiovascular Diseases / epidemiology
  • Cardiovascular Diseases / prevention & control
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Diabetes Mellitus, Type 2 / epidemiology
  • Diabetes Mellitus, Type 2 / pathology
  • Female
  • Humans
  • Hypoglycemia / chemically induced*
  • Hypoglycemia / epidemiology
  • Hypoglycemia / pathology*
  • Hypoglycemic Agents / adverse effects*
  • Magnetic Resonance Imaging*
  • Male
  • Memory / drug effects
  • Middle Aged
  • Risk Factors

Substances

  • Blood Glucose
  • Hypoglycemic Agents

Associated data

  • ClinicalTrials.gov/NCT00182910