title: Habitual coffee consumption enhances attention and vigilance in hemodialysis patients.
abstract: OBJECTIVE
  Coffee drinking is the main source of caffeine intake among adult population in the western world. It has been reported that low to moderate caffeine intake has beneficial effect on alertness and cognitive functions in healthy subjects. The aim of this study is to evaluate the impact of habitual coffee consumption on cognitive function in hemodialysis patients.
  
  
  METHODS
  In a cross-sectional study, 86 patients from a single-dialysis centre underwent assessment by the Montreal Cognitive Assessment tool and evaluation for symptoms of fatigue, mood, and sleep disorders by well-validated questionnaires. The habitual coffee use and the average daily caffeine intake were estimated by participants' response to a dietary questionnaire.
  
  
  RESULTS
  Sixty-seven subjects (78%) consumed black coffee daily, mostly in low to moderate dose. Cognitive impairment was found in three-quarters of tested patients. Normal mental performance was more often in habitual coffee users (25% versus 16%). Regular coffee drinkers achieved higher mean scores on all tested cognitive domains, but a significant positive correlation was found only for items that measure attention and concentration (P = 0.024).
  
  
  CONCLUSIONS
  Moderate caffeine intake by habitual coffee consumption could have beneficial impact on cognitive function in hemodialysis patients due to selective enhancement of attention and vigilance.
authors.affiliation: Special Hospital for Cerebrovascular Disease "Sveti Sava", Nemanjina 2, 11000 Belgrade, Serbia.
authors.forename: Petar M
authors.initials: PM
authors.lastname: Nikić
authors.affiliation: Department of Nephrology, General Hospital, Health Center, 37000 Krusevac, Serbia.
authors.forename: Branislav R
authors.initials: BR
authors.lastname: Andrić
authors.affiliation: Medical Faculty, University of Belgrade, Institute of Nephrology, Clinical Centre of Serbia, 11000 Belgrade, Serbia.
authors.forename: Biljana B
authors.initials: BB
authors.lastname: Stojimirović
authors.affiliation: Department of Nephrology, Clinical Center "DR Dragisa Misovic", 11000 Belgrade, Serbia.
authors.forename: Jasna
authors.initials: J
authors.lastname: Trbojevic-Stanković
authors.affiliation: Medical Faculty, University of Belgrade, Institute of Statistics and Informatics, 11000 Belgrade, Serbia.
authors.forename: Zoran
authors.initials: Z
authors.lastname: Bukumirić
mesh_terms: D001288:Attention / Q000187:drug effects*; D002110:Caffeine / Q000494:pharmacology*; D003069:Coffee / Q000737:chemistry*; D003071:Cognition / Q000187:drug effects; D003710:Demography; D005221:Fatigue / Q000503:physiopathology; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D006435:Renal Dialysis; D012890:Sleep
chemical_list: D003069:Coffee; D002110:Caffeine