EAL

SCI: Lipid Abnormalities (2007)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

Previous research has examined the association between serum cholesterol and LDL in the risk of cardiovascular disease in patients with spinal cord injury. This study assessed the relationship of apoA-1 and apoB levels and CVD risk in patients with SCI, compared to age-matched controls.

Inclusion Criteria:

SCI injury patients were complete paraplegics according to 1996 American Spinal Injury Association standards.

Control patients were selected based on other chronic problems, such as lower back pain, to minimize differences in dietary patterns.

Exclusion Criteria:

Patients taking medication for hyperlipidemia, diabetes or endocrine disorders were excluded from participation.

Description of Study Protocol:

Recruitment

Mechanisms were not discussed. Patients and controls were matched for age and body mass index.

Design

Case-control with one-time measure of serum lipids.

Blinding used (if applicable)

Not discussed.

Intervention (if applicable)

Author indicates a 5 days per week, 90-minute physical activity requirement, but the role in this report is unclear.

Statistical Analysis

T-tests used to determine differences between SCI patients and controls. Pearson's correlations conducted to test associations of lipids parameters in SCI patients.

Data Collection Summary:

Timing of Measurements

Serum lipids were measured after an overnight fast.

Dependent Variables

Serum cholesterol and triglycerides measured using Olympus AU 600.
HDL was determined using phosphotungsten precipitation with enzymatic quantification by spectrophotometry.
Serum LDL was computed based on the Friedewald formula.
Serum apoA-1 and apoB were measured using a nephlometer assay (Beckman Array 360).

Independent Variables

Cases identified based on 1996 American Spinal Injury Association standards.

Control Variables

None indicated.

Description of Actual Data Sample:

Initial N: SCI: 60 (46 males, 14 females), controls: 28 (22 males, 6 females)

Attrition (final N): one-time measurement with no follow-up

Age: SCI: 28.1 years, control: 29.2 years.

Ethnicity: Not indicated

Other relevant demographics: SCI: length of time since injury 3.6±0.8 (1-13 years)

Anthropometrics no differences in the BMI between the 2 groups (23 vs. 22.8)

Location: Gulhane School of Medicine, Ankara, Turkey

Summary of Results:

Variables	SCI Group Means and SD	Control group Means and SD	Statistical Significance of Group Difference
Apo A-1	94±10.3	103±11.5	P=0.003
ApoB	93±15.6	81±13.7	P=0.004
HDL (mg/dL)	33±7.1	44±7.4	P<0.001
LDL (mg/dL)	109±37	91±24	P=0.004

Other Findings

No significant differences were found between total cholesterol, triglycerides and VLDL.

Significant correlations were found within the SCI group for:

apoA-1 and HDL (r=0.753, p<0.001)
apoA-1 and LDL (r=0.947, p<0.001)
apoB and total cholesterol (r=0.87, p<0.001)
apoB and LDL (r=0.782, p<0.001)
apoB and triglycerides (r=0.562, p=0.002)

Author Conclusion:

apoA-1 and apoB provide additional information regarding cardiovascular disease risk in SCI patients. Lack of relationships and difference in LDL may be attributed to the smaller lipoprotein fractions that are not quantified using the calculation method that may provide more insight into CVD risk. serum lipids, including apoA-1 and apoB, should be monitored in patients with SCI.

Funding Source:

University/Hospital:

Gulhane School of Medicine (Ankara, Turkey)

Reviewer Comments:

The report provides very little detail about participant recruitment, data collection and the rationale for the control groups. The use of chronic condition patients may be appropriate for controlling differences in physical activity habits in the groups but likely has no bearing on actual dietary practices, as indicated.

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?	N/A
	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?	No
2.	Was the selection of study subjects/patients free from bias?		No
	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?	???
	2.2.	Were criteria applied equally to all study groups?	???
	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?	No
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)	???
	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?	???
	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.)	No
	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?		N/A
	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?	N/A
	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?	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.)	???
	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?	Yes
	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?		No
	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?	No
	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?	No
	7.3.	Was the period of follow-up long enough for important outcome(s) to occur?	N/A
	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?	No
	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)?	No
	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?	No
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