title: Elevated diet-induced thermogenesis and lipid oxidation rate in Crohn disease.
abstract: BACKGROUND
  Although malnutrition is frequently observed in Crohn disease (CD), its cause is not clear. Regulation of energy metabolism and diet-induced thermogenesis (DIT) have not been adequately studied in CD.
  
  
  OBJECTIVE
  The aim was to study DIT and substrate oxidation in patients with inactive ileal CD.
  
  
  METHODS
  After a test meal providing 50.2 kJ/kg body wt, DIT was assessed by indirect calorimetry performed over 360 min in 18 CD patients and 12 healthy volunteers matched for age, sex, weight, and height. Body composition was evaluated with the labeled-water-bolus injection technique.
  
  
  RESULTS
  Fat-free mass did not differ significantly between groups, but CD patients had markedly lower fat mass than control subjects (13.8+/-5.63 compared with 19.0+/-3.49 kg; P < 0.001). Nonprotein respiratory quotient was lower in CD patients than control subjects (0.80+/-0.04 compared with 0.86+/-0.03; P < 0.001). Average respiratory quotient between 75 and 150 min after the test meal was 0.85+/-0.03 in CD patients and 0.91+/-0.02 in control subjects (P < 0.001). Lipid oxidation rate was higher in CD patients than in control subjects (2.26+/-1.13 compared with 1.50+/-0.75 kJ/min; P < 0.05). DIT was higher in CD patients than in control subjects (9.89+/-1.93% compared with 5.67+/-0.91% of energy intake; P < 0.001).
  
  
  CONCLUSIONS
  Patients with inactive ileal CD had significantly higher DIT and lipid oxidation rate than do healthy volunteers. These results may explain why CD patients have difficulty maintaining adequate nutritional status, and the findings also suggest that a diet relatively rich in fat may attain better energy balance.
authors.affiliation: Cattedra di Medicina Interna II, Centro di Fisiopatologia dello Shock del CNR, Università Cattolica del Sacro Cuore, Rome, Italy. mrccst@tin.it
authors.forename: G
authors.initials: G
authors.lastname: Mingrone
authors.forename: E
authors.initials: E
authors.lastname: Capristo
authors.forename: A V
authors.initials: AV
authors.lastname: Greco
authors.forename: G
authors.initials: G
authors.lastname: Benedetti
authors.forename: A
authors.initials: A
authors.lastname: De Gaetano
authors.forename: P A
authors.initials: PA
authors.lastname: Tataranni
authors.forename: G
authors.initials: G
authors.lastname: Gasbarrini
mesh_terms: D000328:Adult; D001481:Basal Metabolism; D001823:Body Composition; D001835:Body Weight; D002153:Calorimetry, Indirect; D016022:Case-Control Studies; D003424:Crohn Disease / Q000378:metabolism*; D004032:Diet; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D050356:Lipid Metabolism; D008297:Male; D010084:Oxidation-Reduction; D011659:Pulmonary Gas Exchange; D012044:Regression Analysis