PDM: Metabolic Syndrome (2013)


Mujica V, Urzua A, Leiva E, Diaz N, Moore-Carrasco R, Vasquez M, Rojas E, Icaza G, Toro C, Orrego R, Palomo I. Intervention with education and exercise reverses the metabolic syndrome in adults. J Am Soc Hypertens. 2010; 4(3): 148-153.

PubMed ID: 20471000
Study Design:
Randomized Controlled Trial
A - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:

To evaluate the effect of a structured program of exercise and education on adult subjects with metabolic syndrome.

Inclusion Criteria:

Adult subjects with metabolic syndrome defined by ATP III modified criteria recruited from a previous study on metabolic syndrome in adults.

Exclusion Criteria:
  • Diabetes
  • Severely high blood pressure
  • Morbidly obese
  • A history of major disease, such as heart failure, who were unable to perform exercise.
Description of Study Protocol:


Subjects with metabolic syndrome who participated in a previous study on metabolic syndrome in adults were recruited. 


Randomized clinical controlled study.

Blinding Used

Investigators were blinded for anthropometric and biochemical measurements. 


  • Nutrition education presented as four monthly lectures
  • A planned exercise program of three 60-minute aerobic exercise sessions.

Statistical Analysis

  • A Student T-test was used to compare the basal values of each of the metabolic syndrome associated variables (blood pressure, glycemia, triglycerides, HDL-C and waist circumference) between the intervention and the control groups
  • To compare the proportion of subjects with altered factors (hypertension, low HDL-C, high levels of triglycerides, high waist circumference and high glycemia values) between both groups , the Fisher exact test was used
  • To evaluate the effect of the intervention and time (zero and 18 weeks), a mixed linear model with subject random effects was used in the metabolic syndrome-associated variables
  • A Tukey-Kramer multiple comparison P value adjustment was used to evaluate variable changes in time and intervention. A value of P<0.05 was considered significant.
Data Collection Summary:

Timing of Measurements

Measurements made at baseline and at 18 weeks. 

Dependent Variables

  • Body weight using both weight in kg and BMI
  • Waist circumference in cm
  • Blood pressure
  • Fasting blood samples analyzed for glycemia and lipid profile (triglycerides, total cholesterol, and HDL cholesterol).

Independent Variables

  • Four monthly nutrition education sessions (one on consequences of metabolic syndrome, two on caloric content of foods and one on stress management and self-care)
  • The exercise program was a planned program three sessions per week of 60 minutes each. Each consisted of three periods of aerobic exercise, 20 minutes each, in an exercise circuit that included one cycle of ergonometric and elliptical, a rolling band and walking in an internal circuit. The intensities were controlled by cardiac monitors that were programmed individually.
    • First month: Participants worked at 40% cardiac maximal frequency
    • Second month: Patients worked at 60% cardiac maximal frequency
    • The last two months: Patients worked at 80% cardiac maximal frequency.
Description of Actual Data Sample:
  • Initial N: 60 subjects with metabolic syndrome (ATP III modified criteria) were recruited from a previous study. The remaining 51 subjects were randomly assigned to intervention (27) and control groups (24).
  • Attrition (final N): All 51 subjects concluded the trial
  • Age:   
    • Intervention group: 51.1±5.3 years
    • Control group: 49.4±6.2 years
  • Anthropometrics: Groups were similar at baseline, with the exception of HDL-cholesterol in males (P=0.047).
  •  Location: Talca, Chile.
Summary of Results:

Key Findings

  • The I-SM group showed a significant decrease in triglycerides (geometric mean 202.2 to 110.5mg per dL, P<0.001), diastolic blood pressure (mean 85.4 to 79.6mm Hg, P=0.001), waist circumference [(mean: men, 101.5 to 94.1cm; P<0.001) and [mean: women, 107.2 to 96.2cm; P<0.001]), weight (mean: 81.1 to 77.2kg; P<0.001) and BMI (mean: 31.8 to 30.2kg/m2; P<0.001)
  • Conversely, non-intervened subjects did not show significant differences except on total cholesterol, whereas both groups showed significant differences over time
  • Average systolic blood pressure, HDL-C and glycemia were not significantly modified in either group.
Basal and Final (18 weeks) Levels of Variable Associated with Metabolic Syndrome in Intervened and Non-intervened Subjects
  Non- intervened Subjects Intervened Subjects  
  Basal Final Basal Final P*

Body weight (kg)

75.9±10.0 75.2±11.6 81.1±11.5 77.2±11.6 0.012
Waist circumference (cm
     Men 99.3±7.6 99.8±8.7 101.5±8.2 94.1±7.7 <0.001
     Women 101.8±10.6 101.4±9.9 107.2±10.4 96.2±11.3 <0.001
BMI (kg/m2) 29.6±3.8 29.5±4.7 31.8±4.0 30.2±4.0  0.013
SBP (mm Hg) 138.0±15.0 137.6±12.5 135.4±12.9 132.5±13.4  0.638
DBP (mm Hg) 82.7±12.3 82.9±10.5 85.4±10.4 79.6±9.8  0.014
Triglycerides (mg per L)** 186.8±1.7 180.9±1.7 202.2±1.4 110.5±1.5 <0.001
Total cholesterol (mg per dL) 195.0±34.6 191.5±34.6 198.5±32.4 187.0±31.3  0.177
HDL Cholesterol (mg per dL)**
     Men 35.5±1.2 36.8±1.3 41.7±1.1 44.4±1.1  0.747
     Women 44.4±1.3 43.8±1.3  44.8±1.2  46.3±1.2  0.491
 Glycemia 99.8±9.7 97.4±10.6 99.4±9.9 96.3±7.6 .834  

HDL, high-density lipoprotein; BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure.

*Intervention and time interaction P value.

**Results are expressed as the average ± standard deviation, except for triglycerides and HDL cholesterol, which are expressed as geometric mean ± standard deviation.



Author Conclusion:

Patients with metabolic syndrome from Talca, Chile who participated in a systematic, multi-professional, and non-pharmacological intervention of 18 weeks, based on exercise and nutritional advice in order to motivate a healthy lifestyle and nutrition, achieved a high adherence with significant improvements in metabolic parameters.

Funding Source:
University/Hospital: Programa de Investigacion de Factores de Riesgo de Enfermedades Cardiovasculares, Universidad de Talca, Chile
Reviewer Comments:

Groups were significantly different at baseline in terms of HDL-cholesterol in males (P=0.047).

Quality Criteria Checklist: Primary Research
Relevance Questions
  1. Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies) Yes
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? Yes
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? Yes
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) Yes
Validity Questions
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? Yes
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
2. Was the selection of study subjects/patients free from bias? Yes
  2.1. Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study? Yes
  2.2. Were criteria applied equally to all study groups? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? No
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
3. Were study groups comparable? ???
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) Yes
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? No
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) Yes
  3.4. If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis? N/A
  3.5. If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.) N/A
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? N/A
4. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? Yes
  4.2. Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? N/A
  4.5. If diagnostic test, was decision to perform reference test not dependent on results of test under study? N/A
5. Was blinding used to prevent introduction of bias? Yes
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? N/A
  5.2. Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.) Yes
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? N/A
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status? N/A
  5.5. In diagnostic study, were test results blinded to patient history and other test results? N/A
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described? Yes
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied? Yes
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? N/A
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? Yes
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? Yes
  6.6. Were extra or unplanned treatments described? Yes
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? Yes
  6.8. In diagnostic study, were details of test administration and replication sufficient? N/A
7. Were outcomes clearly defined and the measurements valid and reliable? Yes
  7.1. Were primary and secondary endpoints described and relevant to the question? Yes
  7.2. Were nutrition measures appropriate to question and outcomes of concern? Yes
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? Yes
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? Yes
  7.5. Was the measurement of effect at an appropriate level of precision? Yes
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  7.7. Were the measurements conducted consistently across groups? Yes
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? Yes
  8.1. Were statistical analyses adequately described and the results reported appropriately? Yes
  8.2. Were correct statistical tests used and assumptions of test not violated? Yes
  8.3. Were statistics reported with levels of significance and/or confidence intervals? Yes
  8.4. Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)? N/A
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? Yes
  8.6. Was clinical significance as well as statistical significance reported? Yes
  8.7. If negative findings, was a power calculation reported to address type 2 error? N/A
9. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? Yes
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.2. Was the study free from apparent conflict of interest? Yes