Decreased Levels of Serum IGF-1 and Vitamin D Are Associated With Cognitive Impairment in Patients With Type 2 Diabetes

Am J Alzheimers Dis Other Demen. Nov-Dec 2019;34(7-8):450-456. doi: 10.1177/1533317519860334. Epub 2019 Jul 18.


Purpose: To determine the association of serum insulin-like growth factor 1 (IGF-1) and vitamin D levels with cognition status in patients with type 2 diabetes mellitus (T2DM).

Methods: A total of 173 patients with T2DM were recruited and divided into mild cognitive impairment (MCI) group (n = 94) and normal cognition (NC) group (n = 79). Levels of IGF-1 and 25(OH)D were measured and compared, and the correlations among IGF-1, 25(OH)D, and cognitive function were analyzed.

Results: Insulin-like growth factor 1 and 25(OH)D levels significantly decreased in MCI group than those in the NC group (both P < .001). Multiple stepwise regression analysis revealed that IGF-1 (β = .146, P < .001) and 25(OH)D (β = .199, P < .001) independently predicted Montreal Cognitive Assessment (MoCA) scores. Partial least square regression showed that contributions of both 25(OH)D (P < .001) and IGF-1 (P < .001) to MoCA scores were significant, while no cross-effect was observed between them (P = .714).

Conclusions: Low serum IGF-1 and 25(OH)D levels may separately predict poor cognitive performance in patients with diabetes.

Keywords: IGF-1; Montreal Cognitive Assessment; diabetes mellitus; mental status and dementia tests; mild cognitive impairment; type 2; vitamin D.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Calcifediol / blood*
  • Cognitive Dysfunction / blood*
  • Cognitive Dysfunction / etiology
  • Diabetes Complications / blood*
  • Diabetes Mellitus, Type 2 / blood*
  • Diabetes Mellitus, Type 2 / complications
  • Female
  • Humans
  • Insulin-Like Growth Factor I / metabolism*
  • Male
  • Middle Aged


  • IGF1 protein, human
  • Insulin-Like Growth Factor I
  • Calcifediol