Longitudinal factor analysis reveals a distinct clustering of cardiometabolic improvements during intensive, short-term dietary and exercise intervention in obese children and adolescents

Metab Syndr Relat Disord. 2012 Feb;10(1):20-5. doi: 10.1089/met.2011.0050. Epub 2011 Sep 21.

Abstract

Objective: The aim of this study was to investigate changes in cardiometabolic clustering characteristics in response to highly significant weight loss.

Background: Pre-post analysis of a lifestyle intervention for the treatment of obesity and the assessment of interrelated metabolic changes were analyzed using principal component analysis (PCA). A total of n=75 clinically obese boys and girls [standardized body mass index (sBMI) 3.07±0.59] aged 8-18 years were assessed after lifestyle intervention (30±12 days).

Results: There were favorable improvements in BMI waist circumference, fasting insulin, triglycerides (TGs), systolic blood pressure (SBP) and diastolic blood pressure (DBP) (all P<0.001). PCA was performed using a simple conceptual model of changes in six metabolic variables: Overall and central obesity (BMI and waist circumference), dyslipidemia [TG and high-density lipoprotein cholesterol (HDL-C)], insulin resistance [fasting insulin or homeostasis model assessment of insulin resistance (HOMA-IR)], and blood pressure [SBP or mean arterial pressure (MAP)]. PCA models consistently identified two factors underlying the changes in six cardiometabolic variables. These were labeled a "metabolic" factor, typically including waist circumference, fasting triglyceride, insulin, or HOMA-IR and HDL-C (negatively) and an "obesity/blood pressure" factor, typically loading waist, BMI, SBP or MAP, and occasionally fasting insulin/HOMA-IR). The metabolic and obesity/blood pressure factors explained 26.5%-28.4% and 30.4%-31.9%, of the variance in metabolic risk factors changes, respectively. Reductions in BMI, waist circumference, and HOMA-IR (or fasting insulin) were central underlying features of cardiometabolic changes.

Conclusion: There were significant and favorable cardiometabolic risk factor changes to short-term weight-loss. A distinct clustering of cardiometabolic responses supports the etiological importance of both overall and central obesity and insulin resistance in the modification of cardiometabolic risk in obese youths.

MeSH terms

  • Adolescent
  • Biomarkers / blood
  • Blood Glucose / metabolism
  • Blood Pressure
  • Body Mass Index
  • Caloric Restriction*
  • Child
  • Cluster Analysis
  • England
  • Exercise Therapy*
  • Female
  • Humans
  • Insulin / blood
  • Insulin Resistance
  • Lipids / blood
  • Longitudinal Studies
  • Male
  • Obesity / blood
  • Obesity / diagnosis
  • Obesity / diet therapy
  • Obesity / physiopathology
  • Obesity / therapy*
  • Phenotype
  • Principal Component Analysis
  • Recovery of Function
  • Time Factors
  • Treatment Outcome
  • Waist Circumference
  • Weight Loss*

Substances

  • Biomarkers
  • Blood Glucose
  • Insulin
  • Lipids