EAL

SCI: Lipid Abnormalities (2007)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

To compare the standard risk factors for coronary heart disease (CHD) defined in the National Cholesterol Education Program II (NCEP II) of Turkish spinal cord injury (SCI) patients with healthy controls.

Inclusion Criteria:

Spinal Cord Injury patients assessed during rehabilitation at the Cardiovascular Diseases Research Centre, Instanbul, Turkey.

Exclusion Criteria:

CHD patients without SCI.

Description of Study Protocol:

Recruitment

69 patients were assessed during their rehabilitation at the Cardiovascular Diseases Research Centre in Instanbul, Turkey.

Design

Case-matched Cross sectional design

Blinding used (if applicable)

Not discussed

Intervention (if applicable)

N/A

Statistical Analysis

Results were reported as mean +/- Standard Deviation.
Limits of statistical significance were reported at P<0.05
Correlation between the two groups was carried out with Pearson bivariate correlation tests.
Numerical variables were compared with student's t test.
Non-numerical values were compared with X2 test.
In 2 x 2 contingency table Yates correction was done.
When assumptions were violated in 2 x 2 tables Fischer's exact test was used.

Data Collection Summary:

Variables

Body Weight was measred on a balance beam scale designed to accomodate wheelchairs.
Body length was recorded to the nearest centimenter in a supine position using a plastic measuring tape.
Measurements for the abdominal circumference (AC) were made at the umbilicus after a normal expiration with subjects supine.
Conicity index (CI) an indez of abdominal adiposity was measured as described by Valdez et al.
A diastolic blood pressure above 90 mmHg and a systolic blood pressure above 140 mmHg or being on an anti-hypertensive treatment were considered as diagnostic for hypertension.
Diabetes mellitus (DM) and impaired fasting glucose (IFG) were defined according to the report of the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus.
A questionnaire was used to assess alcohol consumption (number of glasses per week), smoking behavior (number of cigarettes per day), and family history of CHD.
Blood samples were obtained after an overnight fast to test for total cholesterol (TC) and triglyceride (TG) concentrations measured using enzymatic tests.
HDL was determined after seletive precipitation of the very low density lipoprotein (VLDL) and low density lipoprotein (LDL).

Control Variables

52 subjects - 14 females (27%), 38 males (73%)
Mean age 35.5 +/- 7.2 years was selected from young medical staff during annual check up exam.
Age, sex, height, obesity, high TG, and smoking were not statistically different between the groups.

Description of Actual Data Sample:

Initial N: 69 SCI patients with a time since injury of 12.8 +/- 13.45 months (range 2-84 months).

Attrition (final N): 69 SCI patients

Age:

Mean age was 33.9 years +/- 11.37 years (range 10-70 years)
Male mean age was 33.7 +/- 12.1, female mean age was 34.6 +/-8.6 years.

Other relevant demographics:

Sixteen females (23%) and 53 males (77%)
67% (45) paraplegics, 33% (24) tetraplegics.
ASIA impairment scale indicated 37 incomplete (54%), and 32 complete (46%) injury.

Anthropometrics

Age, sex, height, obesity, high TG, and smoking were not statistically different between the SCI and control groups.

Location: Instanbul, Turkey

Summary of Results:

Findings

Time since injury was correlated driectly wih TC/HDL and LDL/HDL ratios, inversely with HDL (P<0.01, r = 0.36; P<0.05, r = 0.27; P<0.05, r = -0.26 respectively)
TC (186 +/- 32 vs 205 +/- 36; P =0.025), TC/HDL (5.34 +/- 1.17 vs 6.26+/- 1.5, P=0.005) and LDL/HDL (3.57 +/- 0.9 vs 4.16 +/- 1.3, P=0.027) were increased significantly with time since injury more than one year while HDL levels (35.8 +/-6.36 vs 33.86 +/- 6.47, P=0.213) decreaed without reaching statistical significance.
HDL showed inverse corelations with time since injury, TG, TC/HDL, and LDL/HDL ratios (P<0.05, r = -0.24; P<0.00; r= -0.71; P<0.001, r= -0.57 respectively).
The lipid profiles dd not show any corelation with the neurological level, and completeness of lesion.
There was no statistically significant difference for CHD risk factors in tetraplegics and paraplegics or for complete and incomplete lesions.
SUA levels were directly correlated with TC (P<0.01; r=0.36), TG (P<0.001, r=0.46), and TC/HDL ratio P=0.01, r=0.30)
The SCI group had more risk factors for CHD than did the control group.
The adverse risk profile of increased TC and ratios TC/HDL, LDL/HDL were more common with time since injury greater than 12 months.
TC and LDL levels were significantly increased in 32% and 41% of the SCI patients compared to controls.
HDL levels were significantly depressed in 52% of SCI patients compared to controls (25%).

Author Conclusion:

Compared to other SCI populations, the sample group in this study were younger, smoked more, had higher TC, LDL levels, and TC/HDL, LDL/HDL ratios, but lower prevalence of HT and DM.
SCI seems to confer additional CHD risk factors due to sdentary lifestyle over the pre-existing risk profile of the parent population which increases with time since injury.

Funding Source:

University/Hospital:

Instanbul University Medical Center

Reviewer Comments:

Neither the study group nor the sample size seemed to be representative of the general population and may have skewed data.

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)	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?		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?	No
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)	N/A
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	???
	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.)	Yes
	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?		???
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	???
	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.)	???
	5.3.	In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?	???
	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?	Yes
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	Yes
	6.6.	Were extra or unplanned treatments described?	No
	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?	???
	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?	???
	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)?	Yes
	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?	???
9.	Are conclusions supported by results with biases and limitations taken into consideration?		N/A
	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?		N/A
	10.1.	Were sources of funding and investigators' affiliations described?	Yes
	10.2.	Was the study free from apparent conflict of interest?	Yes