Association of coffee consumption and CYP1A2 polymorphism with risk of impaired fasting glucose in hypertensive patients

Eur J Epidemiol. 2015 Mar;30(3):209-17. doi: 10.1007/s10654-015-9990-z. Epub 2015 Jan 17.


Whether and how coffee use influences glucose metabolism is still a matter for debate. We investigated whether baseline coffee consumption is longitudinally associated with risk of impaired fasting glucose in a cohort of 18-to-45 year old subjects screened for stage 1 hypertension and whether CYP1A2 polymorphism modulates this association. A total of 1,180 nondiabetic patients attending 17 hospital centers were included. Seventy-four percent of our subjects drank coffee. Among the coffee drinkers, 87% drank 1-3 cups/day (moderate drinkers), and 13% drank over 3 cups/day (heavy drinkers). Genotyping of CYP1A2 SNP was performed by real time PCR in 639 subjects. At the end of a median follow-up of 6.1 years, impaired fasting glucose was found in 24.0% of the subjects. In a multivariable Cox regression coffee use was a predictor of impaired fasting glucose at study end, with a hazard ratio (HR) of 1.3 (95% CI 0.97-1.8) in moderate coffee drinkers and of 2.3 (1.5-3.5) in heavy drinkers compared to abstainers. Among the subjects stratified by CYP1A2 genotype, heavy coffee drinkers carriers of the slow *1F allele (59%) had a higher adjusted risk of impaired fasting glucose (HR 2.8, 95% CI 1.3-5.9) compared to abstainers whereas this association was of borderline statistical significance among the homozygous for the A allele (HR 1.7, 95% CI 0.8-3.8). These data show that coffee consumption increases the risk of impaired fasting glucose in hypertension particularly among carriers of the slow CYP1A2 *1F allele.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Blood Glucose / metabolism*
  • Caffeine / adverse effects*
  • Caffeine / metabolism
  • Coffee / adverse effects*
  • Coffee / metabolism
  • Cytochrome P-450 CYP1A2 / genetics*
  • Female
  • Follow-Up Studies
  • Genetic Predisposition to Disease / genetics
  • Genotype
  • Glucose Intolerance / blood
  • Humans
  • Hypertension / complications
  • Hypertension / genetics*
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Polymorphism, Genetic
  • Prediabetic State / etiology
  • Prediabetic State / genetics*
  • Proportional Hazards Models
  • Prospective Studies
  • Reverse Transcriptase Polymerase Chain Reaction
  • Risk Factors


  • Blood Glucose
  • Coffee
  • Caffeine
  • CYP1A2 protein, human
  • Cytochrome P-450 CYP1A2