title: Physical activity and energy expenditure in rheumatoid arthritis patients and matched controls.
abstract: OBJECTIVE
  To compare daily energy expenditure between RA patients and matched controls, and to explore the relationship between daily energy expenditure or sedentariness and disease-related scores.
  
  
  METHODS
  One hundred and ten patients with RA and 440 age- and sex-matched controls were included in this study. Energy expenditure was assessed using the validated physical activity (PA) frequency questionnaire. Disease-related scores included disease activity (DAS-28), functional status (HAQ), pain visual analogue scale (VAS) and fatigue VAS. Total energy expenditure (TEE) and the amount of energy spent in low- (TEE-low), moderate- (TEE-mod) and high-intensity (TEE-high) PAs were calculated. Sedentariness was defined as expending <10% of TEE in TEE-mod or TEE-high activities. Between-group comparisons were computed using conditional logistic regression. The effect of disease-related scores on TEE was investigated using linear regression.
  
  
  RESULTS
  TEE was significantly lower for RA patients compared with controls [2392 kcal/day (95% CI 2295, 2490) and 2494  kcal/day (2446, 2543), respectively, P = 0.003]. A significant difference was found between groups in TEE-mod (P = 0.015), but not TEE-low (P = 0.242) and TEE-high (P = 0.146). All disease-related scores were significantly poorer in sedentary compared with active patients. TEE was inversely associated with age (P < 0.001), DAS-28 (P = 0.032) and fatigue VAS (P = 0.029), but not with HAQ and pain VAS.
  
  
  CONCLUSIONS
  Daily energy expenditure is significantly lower in RA patients compared with matched controls, mainly due to less moderate-intensity PAs performed. Disease activity and fatigue are important contributing factors. These points need to be addressed if promoting PA in RA patients is a health goal. Trial registration. ClinicalTrials.gov, http://clinicaltrials.gov, NCT01228812.
authors.affiliation: Service of Rheumatology, Musculoskeletal Department, Lausanne University Hospital, Av. Pierre-Decker 4, 1011 Lausanne, Switzerland. yves.henchoz@chuv.ch
authors.forename: Yves
authors.initials: Y
authors.lastname: Henchoz
authors.forename: François
authors.initials: F
authors.lastname: Bastardot
authors.forename: Idris
authors.initials: I
authors.lastname: Guessous
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Theler
authors.forename: Jean
authors.initials: J
authors.lastname: Dudler
authors.forename: Peter
authors.initials: P
authors.lastname: Vollenweider
authors.forename: Alexander
authors.initials: A
authors.lastname: So
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000503:physiopathology*; D015992:Body Mass Index; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004734:Energy Metabolism / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005221:Fatigue / Q000209:etiology; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D057185:Sedentary Behavior; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires