MNT: Disorders of Lipid Metabolism (2015)


Sikand G, Kashyap ML, Yang I. Medical nutrition therapy lowers serum cholesterol and saves medication costs in men with hypercholesterolemia. JADA. 1998; 98: 889-894.

Worksheet created prior to Spring 2004 using earlier ADA research analysis template.
Study Design:
Cost effectiveness study.
M - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:

To evaluate whether MNT results in beneficial clinical and cost outcomes.

Inclusion Criteria:
  • Outpatient
  • Primary diagnosis of hypercholesterolemia
  • Met criteria for initiating drug therapy (LDL-cholesterol higher than 4.1mmol per L
  • Not on lipid-lowering medication
  • 21 to 75 years of age
  • Two to four visits to a registered dietician (RD) over a six- to eight-week period.
Exclusion Criteria:

Did not meet inclusion criteria.

Description of Study Protocol:


Medical records review of male patients with hypercholesterolemia who had followed NCEP Step 1 diet for six to eight weeks at a VA Medical Center.


Case series review for cost-benefit analysis.


Two to four MNT sessions with a dietitian.

Statistical Analysis

  • Two-tailed paired T-test to examine changes  for total and LDL- and HDL-cholesterol, triglycerides and BMI
  • Subjects were placed into groups based on number of RD visits (two, three or four) for analysis of covariance adjusted for age and LDL-cholesterol using least significant difference
  • Subjects were evaluated for changes in risk reduction
  • Cost-benefit analysis.
Data Collection Summary:

Timing of Measurements

  • Retrospective chart review evaluating pre- and post-MNT values for lipid profile, BMI
  • Need for lipid-lowering drugs evaluated post-MNT.

Study Variables

  • Number of MNT visits
  • Lipid profile (total, HDL- and LDL-cholesterol, triglycerides)
  • Total cholesterol/HDL-cholesterol ratio
  • LDL/HDL cholesterol ratio
  • BMI
  • Patients needing lipid lowering drugs (per NCEP guidelines)
  • Cost of MNT
  • Cost of lipid-lowering drugs averted as a result of MNT
  • Cost:benefit ratio of MNT to lipid drug therapy (including cost of monitoring).
Description of Actual Data Sample:
  • Initial N: 74 subjects mean age 60.8±9.8 years
  • Location: Veterans Administration Medical Center, Long Beach, CA.
Summary of Results:

As a result of MNT:

  • Decrease total cholesterol 13% (P<0.0001)
  • Decrease LDL-cholesterol 15% (P<0.0001)
  • Decrease TG 11% (P<0.05)
  • Decrease HDL-cholesterol 4% (P<0.05)
  • Average RD time 144±21 minutes
  • Average 2.8±0.7 sessions over 6.8±0.7 weeks
  • Decrease LDL-cholesterol greater with four RD visits compared to two RD visits; decrease 21.9% vs 12.1% (P<0.027)
  • Lipid drug eligibility obviated in 34 out of 67 (51%) of subjects with savings of $60,561.68 from not using the lipid-lowering medicines.
Author Conclusion:

Three to four individualized RD visits of 50 minutes each over seven weeks was associated with significant cholesterol decrease and a savings of health care dollars in avoiding the use of medications.

Funding Source:
Government: Veterans Administration Medical Center
University/Hospital: VAMC Long Beach, CA
Reviewer Comments:

95 subjects were in the cholesterol-lowering drug study; however, data was only available on 74 subjects because 21 subjects dropped out of the original study.

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? 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? Yes
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? Yes
  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? 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? N/A
  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? N/A
  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? 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