PDM: Metabolic Syndrome (2013)


Kolovou GD, Anagnostopoulou KK, Pavlidis AN, Salpea KD, Hoursalas IS, Manolis A, Cokkinos DV. Postprandial lipaemia in menopausal women with metabolic syndrome. Maturitas. 2006; 55(1): 19-26.

PubMed ID: 16443339
Study Design:
Non-Randomized Controlled Trial
C - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:

To evaluate the role of metabolic syndrome, obesity and fasting triglycerides on postprandial response after a high-fat meal.

Inclusion Criteria:

Women of menopausal age.

Exclusion Criteria:
  • Heavy drinking
  • Liver and renal disease
  • Hypothyroidism
  • Professional sport activity.
Description of Study Protocol:


  • Non-randomized controlled trial.
  • The study population was divided into two main groups
    • Metabolic syndrome (METS) group (N=21)
    • Healthy (control) group (N=12)
  • Oral fat tolerance test (OFTT) was given to all participants.
  • Triglyceride levels were measured prior to the test and at two, four, six and eight hours post-OFTT.

Blinding Used

Implied with measurements.


Participants were given a fatty meal containing 75g fat per m2 of body surface area. Participants were forbidden to eat over the next eight hours and had blood drawn at two, four, six and eight hours post-meal.

Statistical Analysis

The level of significance was set at P<0.05. Values of numerical characteristics were tested for normality and are presented as mean value with one standard deviation (SD). The comparison of numerical values between groups was performed with their T-test for independent samples. Areas under the curve (AUC) for serial measurements of triglyceride levels at baseline and after the fatty meal were calculated using the trapezoid rule. Linear regression analysis was performed in order to uncover significant predictors of postprandial lipemia.

Data Collection Summary:

Timing of Measurements

Following a 12-hour overnight fast, blood was drawn at baseline. Participants were then given a fatty meal containing 75g fat per m2 of body surface area. Participants were forbidden to eat over the next eight hours and had blood drawn at two, four, six and eight hours post-meal. 

Dependent Variables

  • Plasma total cholesterol, triglycerides and high-density lipoprotein (HDL) cholesterol measured using enzymatic colorimetric methods on a Roche Integra Biochemical Analyzer
  • Serum low-density lipoprotein (LDL) cholesterol calculated using the Friedewald formula in patients with triglyceride levels less than 400mg per dL
  • Apolipoproteins A, B and lipoprotein(a) measured by nephelometry
  • Blood glucose measured by hexokinase method with a Dade Behring reagent on a Dimension instrument
  • Blood insulin measured with the IMX ABBOTT Diagnostics instrument
  • Body mass index (BMI) was calculated as weight divided by height squared and expressed in kg/m2
  • Whole-body insulin resistance assessed using HOMA-IR and QUICKI parameters.

Independent Variables

Fatty meal containing 75g fat per m2 of body surface area.

Description of Actual Data Sample:
  • Initial N: N=33 women
  • Attrition (final N): N = 33
  • Age: menopausal, 48 to 70 years old
  • Ethnicity: Greek
  • Other relevant demographics: No participants were on hormonal therapy
  • Anthropometrics: By design, the two groups had a different body mass index (BMI) and lipid profile values at baseline. Participants in the METS group were abdominally obese indicated by a high mean value for waist circumference.
  • Location: Greece.
Summary of Results:

Key Findings

Characteristics METS Healthy P Values
Number of subjects 21 12  
Age (years) 57 (7) 59 (11) 0.727
BMI (kg/m2) 30 (3) 25 (3) <0.001
Waist (m) 99 (6) 82 (9) <0.001
Total cholesterol (mg per dL) 242 (46) 203 (34) 0.014
HDL cholesterol (mg per dL) 45 (14) 59 (10) 0.004
LDL cholesterol (mg per dL) 167 (46) 130 (30) 0.017
Glucose (mg per dL) 119 (44) 86 (10) 0.038
Insulin (uU per ml) 119 (44) 86 (10) 0.038
HOMA-IR 2.7 (1.3) 1.1 (0.9) 0.041
QUICKI 3.2 (0.2) 2.9 (2.1) 0.613

Other Findings

  • Significant increases were noted in plasma concentrations of triglyceride levels after meal consumption in METS compared to healthy subjects
  • METS subjects with more than 30kg/m2 showed no additional exaggeration of triglycerides postprandially
  • METS subjects with fasting triglycerides more than 150mg per dL expressed higher AUC values than normotriglycerideamic subjects
  • Linear regression showed that for every rise of 1mg of the fasting triglyceride values, the AUC increased by 11.866mg per dL per hour. When METS women were grouped according to BMI status (overweight vs. obese), obesity was not a further determinant for postprandial triglyceride rising.
Author Conclusion:

The authors concluded that fasting triglyceride concentration is the main determinant of the postprandial lipemia, while the obesity state does not further exaggerate the postprandial response in menopausal METS women. The abnormal postprandial lipemia should be added as an important metabolic disturbance to the METS.

Funding Source:
University/Hospital: Onassis Cardiac Surgery Center, Tzanio State Hospital, Boston University
Reviewer Comments:

Small numbers of subjects in groups.

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? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
3. Were study groups comparable? Yes
  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? Yes
  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? N/A
  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%.) N/A
  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? No
  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? N/A
  6.6. Were extra or unplanned treatments described? N/A
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? N/A
  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? Yes
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? No
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