Olfactory dysfunction in type 2 diabetes mellitus: an additional manifestation of microvascular disease?

Angiology. 2014 Nov;65(10):869-76. doi: 10.1177/0003319714520956. Epub 2014 Feb 19.

Abstract

We evaluated olfactory dysfunction in 154 adults (74 men, mean age 60.9±11.9 years), of whom 119 had type 2 diabetes mellitus (T2DM). Olfactory function was assessed with "Sniffin' Sticks." A total Threshold-Discrimination-Identification (TDI) score was calculated. Type 2 diabetes mellitus, hypertension, and hyperlipidemia were associated with lower olfactory scores (all TDI scores<0.001). Age was negatively associated with odor threshold, odor identification, and TDI score (P=.009, <.001, and <.001, respectively). After adjusting for age, gender, body mass index, smoking, alcohol, diabetes, hypertension, hyperlipidemia, and cardiovascular disease, only T2DM and hypertension were associated with TDI score (R square=0.281). Diabetic complications were associated with olfactory dysfunction (P=.006): TDI scores were lower in the presence of diabetic peripheral neuropathy (P=.017) and retinopathy (P=.047). In conclusion, T2DM and hypertension are independently associated with olfactory dysfunction while diabetic peripheral neuropathy and retinopathy are significantly associated with lower olfactory scores. The clinical relevance of these findings needs to be further examined.

Keywords: Sniffin’ Sticks; diabetic complications; olfaction; type 2 diabetes mellitus.

MeSH terms

  • Adult
  • Age Factors
  • Aged
  • Cross-Sectional Studies
  • Diabetes Mellitus, Type 2 / complications*
  • Diabetic Angiopathies / complications*
  • Discrimination, Psychological
  • Female
  • Humans
  • Hyperlipidemias / complications
  • Hypertension / complications
  • Male
  • Microcirculation
  • Middle Aged
  • Olfaction Disorders / etiology*
  • Risk Factors
  • Sensory Thresholds