Prediction modelling of 1-year outcomes to a personalized lifestyle intervention for Canadians with metabolic syndrome

Metabolic syndrome (MetS) comprises a cluster of risk factors that includes central obesity, hypertension, dyslipidemia, and impaired glucose homeostasis. Although lifestyle interventions reduce MetS risk, not everyone responds to the same extent. The primary objective of this study was to identify variables that could predict 1-year changes in MetS risk in individuals participating in the Canadian Health Advanced by Nutrition and Graded Exercise (CHANGE) program. Participants were allocated into training (n = 157) and test (n = 29) datasets by availability of genetic data. A linear mixed-effect model revealed that age, medication, fasting glucose, triglycerides, high-density lipoprotein cholesterol, waist circumference, systolic blood pressure, and fibre intake were associated with continuous MetS (cMetS) score across all time points. Multiple linear regressions were then used to build 2 prediction models using 1-year cMetS score as the outcome variable. Model 1 included only baseline variables and was 38% accurate for predicting cMetS score. Model 2 included both baseline variables and the 3-month change in cMetS score and was 86% accurate. As a secondary objective, we also examined if we could build a model to predict a person’s categorical response bin (i.e., positive responder, nonresponder, or adverse responder) at 1 year using the same variables. We found 72% concordance between predicted and observed outcomes. These various prediction models need to be further tested in independent cohorts but provide a potentially promising new tool to project patient outcomes during lifestyle interventions for MetS. Novelty Short-term changes in cMetS score improve prediction model performance compared with only baseline variables. Predictive models could potentially facilitate clinical decision-making for personalized treatment plans.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Evaluation of Latent Models Assessing Physical Fitness and the Healthy Eating Index in Community Studies: Time-, Sex-, and Diabetes-Status Invariance

Accurate measurement requires assessment of measurement equivalence/invariance (ME/I) to demonstrate that the tests/measurements perform equally well and measure the same underlying constructs across groups and over time. Using structural equation modeling, the measurement properties (stability and responsiveness) of intervention measures used in a study of metabolic syndrome (MetS) treatment in primary care offices, were assessed. The primary study (N = 293; mean age = 59 years) had achieved 19% reversal of MetS overall; yet neither diet quality nor aerobic capacity were correlated with declines in cardiovascular disease risk. Factor analytic methods were used to develop measurement models and factorial invariance were tested across three time points (baseline, 3-month, 12-month), sex (male/female), and diabetes status for the Canadian Healthy Eating Index (2005 HEI-C) and several fitness measures combined (percentile VO2 max from submaximal exercise, treadmill speed, curl-ups, push-ups). The model fit for the original HEI-C was poor and could account for the lack of associations in the primary study. A reduced HEI-C and a 4-item fitness model demonstrated excellent model fit and measurement equivalence across time, sex, and diabetes status. Increased use of factor analytic methods increases measurement precision, controls error, and improves ability to link interventions to expected clinical outcomes

Patient experiences of a lifestyle program for metabolic syndrome offered in family medicine clinics: a mixed methods study

Abstract Background Patient perspectives on new programs to manage metabolic syndrome (MetS) are critical to evaluate for possible implementation in the primary healthcare system. Participants’ perspectives were sought for the Canadian Health Advanced by Nutrition and Graded Exercise (CHANGE) study, which enrolled 293 participants, and demonstrated 19% reversal of MetS after 1 year. The main purpose of this study was to examine participants’ perceptions of their experiences with the CHANGE program, enablers and barriers to change. Methods A convergent parallel mixed methods design combined patients’ perspectives collected by questionnaires (n = 164), with insights from focus groups (n = 41) from three sites across Canada. Qualitative data were thematically analyzed using interpretative description. Insights were organized within a socio-ecologic framework. Results Key aspects identified by participants included intra-individual factors (personal agency, increased time availability), inter-individual factors (trust, social aspects) and organizational factors (increased mental health support, tailored programs). Conclusion Results revealed participants’ overall support for the CHANGE program, especially the importance of an extended program under the guidance of a family physician along with a skilled and supportive team. Team delivery of a lifestyle program in primary care or family medicine clinics is a complex intervention and use of a mixed methods design was helpful for exploring patient experiences and key issues on enablers and barriers to health behavior change

Relationship between Cardiometabolic Factors and the Response of Blood Pressure to a One-Year Primary Care Lifestyle Intervention in Metabolic Syndrome Patients

Systemic hypertension has been recognized as a modifiable traditional cardiovascular risk factor and influenced by many factors such as eating habits, physical activity, diabetes, and obesity. The objective of this cross-sectional study was to identify factors that predict changes in blood pressure induced by a one-year lifestyle intervention in primary care settings involving a collaboration between family physicians, dietitians, and exercise specialists. Patients with metabolic syndrome diagnosis were recruited by family physicians participating in primary care lifestyle intervention among several family care clinics across Canada. Participants for whom all cardiometabolic data at the beginning (T0) and the end (T12) of the one-year intervention were available were included in the present analysis (n = 101). Patients visited the dietitian and the exercise specialist weekly for the first three months and monthly for the last nine months. Diet quality, exercise capacity, anthropometric indicators, and cardiometabolic variables were evaluated at T0 and at T12. The intervention induced a statistically significant decrease in waist circumference (WC), systolic (SBP) and diastolic (DBP) blood pressure, and plasma triglycerides, and an increase in cardiorespiratory fitness (estimated VO2max). Body weight (p p p = 0.006) reduction, and VO2max increase (p = 0.048) were all related to changes in SBP. WC was the only variable for which changes were significantly correlated with those in both SBP (p p = 0.0004). Variations in DBP were not associated with changes in other cardiometabolic variables to a statistically significant extent. Twelve participants were identified as adverse responders (AR) in both SBP and DBP and displayed less favorable changes in WC. The beneficial effects of the primary care lifestyle intervention on blood pressure were significantly associated with cardiometabolic variables, especially WC. These findings suggest that a structured lifestyle intervention in primary care can help improve cardiometabolic risk factors in patients with metabolic syndrome and that WC should be systematically measured to better stratify the patient’s hypertension risk

Nutrient Intake and Dietary Quality Changes within a Personalized Lifestyle Intervention Program for Metabolic Syndrome in Primary Care

A team-based 12-month lifestyle program for the treatment of metabolic syndrome (MetS) (involving physicians, registered dietitians (RDs), and kinesiologists) was previously shown to reverse MetS in 19% of patients (95% confidence interval, 14% to 24%). This work evaluates changes in nutrient intake and diet quality over 12 months (n = 205). Individualized diet counselling was provided by 14 RDs at 3 centres. Two 24-h recalls, the Canadian Healthy Eating Index (HEI-C), and the Mediterranean Diet Score (MDS) were completed at each time point. Total energy intake decreased by 145 ± 586 kcal (mean ± SD) over 3 months with an additional 76 ± 452 kcal decrease over 3–12 months. HEI-C improved from 58 ± 15 to 69 ± 12 at 3 months and was maintained at 12 months. Similarly, MDS (n = 144) improved from 4.8 ± 1.2 to 6.2 ± 1.9 at 3 months and was maintained at 12 months. Changes were specific to certain food groups, with increased intake of fruits, vegetables, and nuts and decreased intake of “other foods” and “commercial baked goods” being the most prominent changes. There was limited change in intake of olive oil, fish, and legumes. Exploratory analysis suggested that poorer diet quality at baseline was associated with greater dietary changes as assessed by HEI-C. Novelty Multiple dietary assessment tools provided rich information on food intake changes in an intervention for metabolic syndrome. Improvements in diet were achieved by 3 months and maintained to 12 months. The results provide a basis for further dietary change implementation studies in the Canadian context.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author