title: Predictors of change in objectively measured and self-reported health behaviours among individuals with recently diagnosed type 2 diabetes: longitudinal results from the ADDITION-Plus trial cohort.
abstract: BACKGROUND
  There is limited evidence about predictors of health behaviour change in people with type 2 diabetes. The aim of this study was to assess change in health behaviours over one year and to identify predictors of behaviour change among adults with screen-detected and recently clinically diagnosed diabetes.
  
  
  METHODS
  ADDITION-Plus was a randomised controlled trial of a behaviour change intervention among 478 patients (40-69 years). Physical activity and diet were measured objectively (physical activity at 1 year) and by self-report at baseline and one year. Associations between baseline predictors and behaviour change were quantified using multivariable linear regression.
  
  
  RESULTS
  Participants increased their plasma vitamin C and fruit intake, reduced energy and fat intake from baseline to follow-up. Younger age, male sex, a smaller waist circumference, and a lower systolic blood pressure at baseline were associated with higher levels of objectively measured physical activity at one year. Greater increases in plasma vitamin C were observed in women (beta-coefficient [95% CI]: beta = -5.52 [-9.81, -1.22]) and in those with screen-detected diabetes (beta = 6.09 [1.74, 10.43]). Younger age predicted a greater reduction in fat (beta = -0.43 [-0.72, -0.13]) and energy intake (beta = -6.62 [-13.2, -0.05]). Patients with screen-detected diabetes (beta = 74.2 [27.92, 120.41]) reported a greater increase in fruit intake. There were no significant predictors of change in self-reported physical activity. Beliefs about behaviour change and diabetes did not predict behaviour change.
  
  
  CONCLUSIONS
  Older patients, men and those with a longer duration of diabetes may need more intensive support for dietary change. We recommend that future studies use objective measurement of health behaviours and that researchers add predictors beyond the individual level. Our results support a focus on establishing healthy lifestyle changes early in the diabetes disease trajectory.
authors.forename: Laura
authors.initials: L
authors.lastname: Kuznetsov
authors.forename: Rebecca K
authors.initials: RK
authors.lastname: Simmons
authors.forename: Stephen
authors.initials: S
authors.lastname: Sutton
authors.forename: Ann-Louise
authors.initials: AL
authors.lastname: Kinmonth
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Griffin
authors.affiliation: The Primary Care Unit, Cambridge Institute of Public Health, University of Cambridge, Robinson Way, Cambridge CB2 0SR, UK. wh207@medschl.cam.ac.uk.
authors.forename: Wendy
authors.initials: W
authors.lastname: Hardeman
mesh_terms: D000328:Adult; D000368:Aged; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis* / Q000628:therapy; D004032:Diet; D004041:Dietary Fats / Q000008:administration & dosage; D002149:Energy Intake; D005247:Feeding Behavior; D005260:Female; D005500:Follow-Up Studies; D005638:Fruit; D015438:Health Behavior; D006801:Humans; D008019:Life Style; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D015999:Multivariate Analysis; D057566:Self Report; D012959:Socioeconomic Factors
chemical_list: D004041:Dietary Fats; D001205:Ascorbic Acid