EAL

Citation:

Al-Sarraj T, Saadi H, Volek JS, Fernandez ML. Metabolic syndrome prevalence, dietary intake, and cardiovascular risk profile among overweight and obese adults 18-50 years old from the United Arab Emirates. Metab Syndr Relat Disord. 2010; 8 (1): 39-46.

PubMed ID: 19929603

Study Design:

Cross-Sectional Study

Class:

D - Click here for explanation of classification scheme.

Quality Rating:

NEUTRAL: See Quality Criteria Checklist below.

Research Purpose:

To screen overweight and obese adult Emirati citizens, aged 18 to 50 years, to determine the prevalence of metabolic syndrome (MS), and to assess the most relevant criteria associated with MS in this population
Secondly, to evaluate the contribution of lipoprotein subfractions to the distinctive plasma lipids characterized by high-low density lipoproteins (LDL), low-high density lipoproteins (HDL) and low triglycerides (TG) in a subset of this population.

Inclusion Criteria:

Overweight and obese Emirati adults living in the city of Al-Ain, Emirati of Abu Dhabi were recruited to be screened for MS at the Tawam hospital, one of the major tertiary hospitals in the United Arab Emirates (UAE).

Exclusion Criteria:

Non-UAE citizens
Younger than 18 or older than 50 years old
Pregnancy and lactation
Thyroid problems
Use of medication relevant to type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD)
T2DM or fasting blood glucose greater than 126mg/dL, stroke, or heart disease.

Description of Study Protocol:

Recruitment

Written and word-by-mouth advertisement for a MS screening program was circulated among the hospital Emirati employees and their relatives, UAE University and Faculty of Medicine and Higher College of Technology students, in addition to random governmental schools and institutions in Al-Ain City.

Design

Cross-sectional study

Blinding used

Implied with measurements

Intervention

Not applicable

Statistical Analysis

Two-way analysis of variance (ANOVA) (gender, MS) was used to analyze plasma lipids, glucose, and anthropometric parameters among men and women with and without MS
P<0.05 was considered statistically significant
A subset of 39 samples (13 men, 26 women) was used to determine dietary intake and lipoprotein subfraction number and average size
Independent t-test was used to evaluated differences between men and women.

Data Collection Summary:

Timing of Measurements

Baseline data collection

Dependent Variables

Metabolic syndrome effect
- Plasma glucose
- Plasma lipids
- Anthropometric measures
Gender effect.

Independent Variables

Subjects with and without MS
Dietary intake (subgroup).

Control Variables

Description of Actual Data Sample:

Initial N: N=227 overweight/obese Emirati adults
- n=153 women
- n=74 men
Attrition (final N): N=227
Age: 18 to 50 years old
Ethnicity: Arab
Other relevant demographics:
- 92/227=40.5% of the subjects with a prevalence of MS
- No MS: N=38 men; N=96 women
- With MS: N=36; N=57 women
Anthropometrics: Subjects with MS had a higher body mass index (BMI), waist circumference, and weight (kg) compared to men and women who did not have MS
Location: City of Al-Ain, Emirati of Abu Dhabi, United Arab Emirates.

Summary of Results:

Key Findings

A total of 92/227 subjects (40.5%) were classified as having metabolic syndrome
- Subjects with MS were older (P<0.01), heavier (P<0.01) and had a higher BMI (P<0.01) compared to subjects without MS
Only 7% of subjects had TG >1.7mmol/L, whereas 95% had plasma LDL-C >2.6mmol/L
- Men had higher LDL (P<0.05) and lower HDL (P<0.01) compared to women
- Subjects with MS had higher concentrations of total cholesterol (P<0.01) and LDL (P<0.01) compared to those subjects without MS
Dietary analysis (N=39) revealed high-energy consumption, with diets high in total carbohydrates, fat, and simple sugars
- Total energy intake for men: 20,971±5,466kJ; Women: 17,180±5,138kJ (intake for men was higher, (P<0.05)
- Men consumed more grams of fat per day (P<0.01) compared to women
- Mean intake of total sugars was 213 grams per day for the sample
- Mean energy contribution from saturated fat was 10.6% for the sample
- Energy intake was positively correlated with WC for both men (r=0.768, P<0.01) and women (r=0.545, P<0.01)
Subjects were sedentary with only 14% of the sample engaged in physical activity
In men, BMI was significantly and positively correlated with WC, blood pressure and LDL, whereas in women all parameters of MS were positively correlated with BMI except for HDL, which was negatively correlated (P<0.01)
In men, age was positively correlated with systolic blood pressure,TG, LDL (P<0.01), whereas in women age was positively correlated with WC, TG, and LDL
Women had more large and medium HDL particles compared to men (P<0.05)
Men had a higher number of small HDL particles compared to women (P<0.05).

Author Conclusion:

The authors concluded that the high prevalence of MS among overweight/obese Emirati adults predisposes this population to increased risk for developing diabetes and cardiovascular disease.

Funding Source:

Other:

Health Authority for the Emirate of Abu Dhabi

Reviewer Comments:

Relatively small sample for a cross-sectional study design, especially with regards to the subset analyses (N=39)
More demographic information about the subjects would have been useful (socioeconomic status, employment, marital status, etc) to determine if this was truly a valid sample of the local population
Dietary information and lipid subfraction data were not collected on those individuals who did not have MS, therefore a comparison between those subjects with MS and those subjects without MS on these dietary and lipid data was not conducted. This information could have added more value to the study in assessing the population sample.

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)	N/A
	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)	N/A

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?		???
	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?	???
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?	Yes
	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%.)	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?	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?	Yes
	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?	N/A
	6.2.	In observational study, were interventions, study settings, and clinicians/provider described?	Yes
	6.3.	Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?	N/A
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	N/A
	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?	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