title: Efficacy of a family practice-based lifestyle intervention program to increase physical activity and reduce clinical and physiological markers of vascular health in patients with high normal blood pressure and/or high normal blood glucose (SNAC): study protocol for a randomized controlled trial.
abstract: BACKGROUND
  Previous interventions to increase physical activity and reduce cardiovascular risk factors have been targeted at individuals with established disease; less attention has been given to intervention among individuals with high risk for disease nor has there been determination of the influence of setting in which the intervention is provided. In particular, family practice represents an ideal setting for the provision and long-term maintenance of lifestyle interventions for patients at risk (ie high-normal blood pressure or impaired glucose tolerance).
  
  
  METHODS
  The Staged Nutrition and Activity Counseling (SNAC) study is a randomized clustered design clinical trial that will investigate the effectiveness and efficacy of a multi-component lifestyle intervention on cardiovascular disease risk factors and vascular function in patients at risk in primary care. Patients will be randomized by practice to either a standard of care lifestyle intervention or a behaviourally-based, matched prescriptive physical activity and diet change program. The primary goal is to increase physical activity and improve dietary intake according to Canada's Guides to Physical Activity Healthy Eating over 24 months. The primary intention to treat analysis will compare behavioral, physiological and metabolic outcomes at 6, 12 and 24 months post-randomization including estimation of incident hypertension and/or diabetes.
  
  
  CONCLUSIONS
  The design features of our trial, and the practical problems (and solutions) associated with implementing these design features, particularly those that result in potential delay between recruitment, baseline data collection, randomization, intervention, and assessment will be discussed. Results of the SNAC trial will provide scientific rationale for the implementation of this lifestyle intervention in primary care.
  
  
  BACKGROUND
  ISRCTN: ISRCTN:42921300.
authors.affiliation: Dept of Family Medicine, Schulich School of Medicine, University of Western Ontario, Canada. petrella@uwo.ca
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Petrella
authors.forename: Kuni
authors.initials: K
authors.lastname: Aizawa
authors.forename: Kevin
authors.initials: K
authors.lastname: Shoemaker
authors.forename: Tom
authors.initials: T
authors.lastname: Overend
authors.forename: Len
authors.initials: L
authors.lastname: Piche
authors.forename: Mauricio
authors.initials: M
authors.lastname: Marin
authors.forename: Sheree
authors.initials: S
authors.lastname: Shapiro
authors.forename: Sophie
authors.initials: S
authors.lastname: Atkin
mesh_terms: D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D016000:Cluster Analysis; D004032:Diet; D015444:Exercise; D005194:Family Practice; D018149:Glucose Intolerance / Q000097:blood / Q000150:complications / Q000175:diagnosis / Q000628:therapy*; D006801:Humans; D009864:Ontario; D011236:Prediabetic State / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D058246:Prehypertension / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D012107:Research Design; D018570:Risk Assessment; D012307:Risk Factors; D040242:Risk Reduction Behavior; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D001786:Blood Glucose