Comorbid type 2 diabetes mellitus and hypertension exacerbates cognitive decline: evidence from a longitudinal study

Age Ageing. 2004 Jul;33(4):355-61. doi: 10.1093/ageing/afh100. Epub 2004 May 10.


Background: diabetes and hypertension are two highly prevalent diseases in the old population. They are highly related such that comorbidity is common.

Objectives: to examine (i) the independent impact of the respective diseases on cognitive decline in very old age and (ii) the interactive impact of the two diseases on cognitive decline.

Subjects: 258 individuals (mean age = 83 years), all non-demented at baseline. Of these, 128 individuals (non-cases) were free from diabetes and hypertension, 92 individuals had a diagnosis of hypertension, 16 had a type 2 diabetes mellitus diagnosis without hypertension, and 22 had comorbid diabetes and hypertension.

Method: a population-based longitudinal study of ageing (The OCTO-Twin Study), including four measurement occasions 2 years apart. The Mini-Mental State Examination was used to measure general cognitive function. Data were analysed using SAS Proc Mixed multilevel modelling.

Results: longitudinal trajectories indicated a steeper decline in cognitive function related to diabetes but not related to hypertension. However, the results indicated greatest cognitive decline among persons with comorbid diabetes and hypertension.

Conclusions: it is concluded that comorbidity of diabetes and hypertension produce a pronounced cognitive decline. This finding emphasises the importance of prevention and treatment of those highly prevalent diseases in the old population.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Cognition / physiology*
  • Dementia / etiology
  • Diabetes Mellitus, Type 2 / complications*
  • Diabetes Mellitus, Type 2 / psychology*
  • Female
  • Humans
  • Hypertension / complications*
  • Hypertension / psychology*
  • Longitudinal Studies
  • Male