Metabolic abnormalities associated with cognitive dysfunction
medwireNews: Impaired fasting plasma glucose and insulin resistance are associated with an increased risk for developing cognitive dysfunction among postmenopausal women, results of a Danish study suggest.
In an analysis of data from 1759 participants of the Prospective Epidemiological Risk Factor study, the researchers found that women with impaired fasting plasma glucose (>5.6 mmol/L) at baseline were significantly more likely to have cognitive dysfunction – as measured by a category fluency test with animal naming (CFT) score of 14 points or less – after 15 years of follow-up compared with normoglycemic individuals, with an adjusted odds ratio (OR) of 1.44.
Furthermore, participants with a poor metabolic profile, indicated by the presence of all five components of the metabolic syndrome (body mass index >30 kg/m2, triglycerides >1.7 mmol/L, high density lipoprotein cholesterol <1.29 mmol/L, fasting plasma glucose >5.6 mmol/L, and hypertension), were approximately three times more likely to develop cognitive dysfunction based on CFT scores than those than metabolically normal individuals (OR=3.07).
Those with all five components of the metabolic syndrome were also significantly more likely to develop cognitive dysfunction as measured by a combination of CFT scores and the Short Blessed Test (SBT) – an assessment of orientation, concentration, and memory – than those with no risk factors (OR=4.35).
However, participants with one to four metabolic syndrome components did not have a significantly increased risk for cognitive dysfunction at follow-up.
The researchers also identified an association between insulin resistance and cognition; women with a homeostasis model assessment of insulin resistance (HOMA-IR) index score of more than 2.6 at baseline had a significantly higher risk for cognitive dysfunction based on CFT scores (OR=1.47) compared with those below the threshold.
And when analyzing insulin resistance as a continuous variable, the risk for cognitive dysfunction by CFT and a combination of CFT and SBT increased by a respective 8% and 10% for every unit increase on the HOMA-IR index scale, reports the team in Diabetes.
Jesper Neergaard (Nordic Bioscience A/S, Herlev, Denmark) and colleagues believe that their findings “can be taken to indicate a temporal relation between [insulin resistance] and cognitive dysfunction,” but stress that the observational study design “does not allow for causal conclusions.”
“[Insulin resistance] may be a shared underlying pathological mechanism, since it is part of the prodromal phase of both type 2 diabetes and dementia,” they add.
And the researchers conclude: “If the observed association […] is truly causal it could suggest that a significant proportion of dementia cases in women may be preventable by effective control of insulin homeostasis.”
medwireNews is an independent medical news service provided by Springer Healthcare. © 2017 Springer Healthcare part of the Springer Nature group