Differences in vitamin D concentration between metabolically healthy and unhealthy obese adults: associations with inflammatory and cardiometabolic markers in 4391 subjects

Diabetes Metab. 2014 Nov;40(5):347-55. doi: 10.1016/j.diabet.2014.02.007. Epub 2014 May 5.

Abstract

Aim: This study aimed to compare concentrations of serum 25-hydroxy vitamin D and inflammatory markers in metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO), and to determine whether the relationship between vitamin D levels and both cardiometabolic and inflammatory markers differs between MHO and MUO.

Methods: This cross-sectional study comprised 4391 obese subjects aged>18 years. A panel of cardiometabolic and inflammatory markers, including anthropometric variables, glycaemic indices, lipid profiles, liver enzymes, homocysteine, C-reactive protein (CRP), fibrinogen and serum 25-hydroxy vitamin D levels, was investigated. All cardiometabolic and inflammatory markers in MHO and MUO as well as in vitamin D deficiency were compared.

Results: Prevalence of MHO was 41.9% in our obese subjects using International Diabetes Federation criteria. Considering insulin resistance and inflammation, the prevalence of MHO was 38.4%. Individuals with MHO had significantly higher vitamin D concentrations compared with MUO, and this difference in vitamin D status persisted after accounting for BMI and waist circumference. Subjects with MHO had significantly better metabolic status, lower liver enzymes, lower inflammatory markers and higher serum 25-hydroxy vitamin D than those with MUO. Associations between vitamin D levels and inflammatory and cardiometabolic markers differed according to MHO/MUO status. Among MUO subjects, vitamin D deficiency was associated with higher liver marker and homocysteine levels. Serum vitamin D was negatively associated with fasting plasma glucose and HbA1c in MHO only.

Conclusion: Serum 25-hydroxy vitamin D levels were lower in MUO vs MHO, and reduced vitamin D concentrations were more strongly associated with cardiometabolic and inflammatory markers in MUO than in MHO subjects. These findings suggest that a deficiency in vitamin D could be a key component of MUO.

Keywords: Metabolic syndrome; Obesity; Vitamin D.

Publication types

  • Comparative Study
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers / blood
  • Blood Pressure
  • Body Mass Index
  • C-Reactive Protein / metabolism
  • Cardiovascular Diseases / blood*
  • Cardiovascular Diseases / physiopathology
  • Cardiovascular Diseases / prevention & control
  • Cross-Sectional Studies
  • Female
  • Fibrinogen / metabolism
  • Glycated Hemoglobin A / metabolism
  • Homocysteine / blood
  • Humans
  • Inflammation / blood*
  • Inflammation / physiopathology
  • Insulin Resistance
  • Iran / epidemiology
  • Lipids / blood
  • Liver / enzymology*
  • Male
  • Metabolic Syndrome / blood*
  • Metabolic Syndrome / physiopathology
  • Metabolic Syndrome / prevention & control
  • Middle Aged
  • Obesity / blood*
  • Obesity / epidemiology
  • Obesity / physiopathology
  • Vitamin D / analogs & derivatives*
  • Vitamin D / blood
  • Waist Circumference

Substances

  • Biomarkers
  • Glycated Hemoglobin A
  • Lipids
  • hemoglobin A1c protein, human
  • Homocysteine
  • Vitamin D
  • Fibrinogen
  • C-Reactive Protein
  • 25-hydroxyvitamin D