title: Influence of caffeine on frequency of hypoglycemia detected by continuous interstitial glucose monitoring system in patients with long-standing type 1 diabetes.
abstract: OBJECTIVE
  The aim of this study was to investigate the effect of caffeine (in doses equivalent to normal daily ingestion) on rates and severity of hypoglycemia in patients with long-standing type 1 diabetes to determine the relationship between caffeine, autonomic function, and hypoglycemia.
  
  
  METHODS
  Using a double-blinded randomized study, we investigated the effect of caffeine versus placebo in 19 patients with long-standing type 1 diabetes using continuous glucose sensing technology and simultaneous assessment of autonomic function using Holter monitoring.
  
  
  RESULTS
  Caffeine reduced the duration of nocturnal hypoglycemia with a mean duration of 49 minutes (range 0-235) versus 132 (0-468) minutes (P = 0.035). The reduction in duration of nighttime hypoglycemia was due to a decline in the number of episodes of moderate hypoglycemia at the expense of mild hypoglycemic episodes (P = 0.04). There was no overall correlation between reduced heart rate variability (a marker of autonomic dysfunction) and hypoglycemic events (r(s) = 0.12, P = 0.62).
  
  
  CONCLUSIONS
  Our results suggest that caffeine is associated with a significant reduction in nocturnal hypoglycemia. The reduction in nocturnal hypoglycemia was not linked to the concomitant rise in parasympathetic activity associated with caffeine.
authors.affiliation: Bournemouth Diabetes and Endocrine Centre, Royal Bournemouth Hospital, Castle Lane East, Bournemouth BH7 7DW, U.K. tristan.richardson@rbch.nhs.uk
authors.forename: Tristan
authors.initials: T
authors.lastname: Richardson
authors.forename: Peter
authors.initials: P
authors.lastname: Thomas
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Ryder
authors.forename: David
authors.initials: D
authors.lastname: Kerr
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism*; D001794:Blood Pressure; D002110:Caffeine / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000494:pharmacology; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D004311:Double-Blind Method; D005260:Female; D006339:Heart Rate; D006801:Humans; D007003:Hypoglycemia / Q000453:epidemiology* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory; D010919:Placebos
chemical_list: D001786:Blood Glucose; D000697:Central Nervous System Stimulants; D010919:Placebos; D002110:Caffeine