DM: Carbohydrates (2007)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
To study the metabolic effects of sucrose included in the diet of Type I diabetic outpatients treated with continuous subcutaneous insulin infusion.
Inclusion Criteria:

Type I diabetes.

Exclusion Criteria:
None.
Description of Study Protocol:

Recruitment:  not specified

Design:  4-week run in period, followed by randomized 4-week periods of each of two diets:  use of sucrose as sweetener or cyclamate as sweetener

Blinding used (if applicable): not possible, as sweeteners were easily distinguishable

Intervention (if applicable)

  • Sucrose period
    • sucrose and sucrose-sweetened foods allowed ad libitum
    • sucrose-sweetened soft drinks discouraged
  • Cyclamate period:  sodium cyclamate allowed ad libitum up to a maxium of 11 mg/kg body weight per day

Statistical Analysis

Student's t-test used for paired and unpaired comparison

 

Data Collection Summary:

Timing of Measurements

  • glucose readings, daily insulin dose, and intake of carbohydrates recorded every day by patient

Dependent Variables

  • blood glucose: subjects performed regular blood glucose self-monitoring, which was "repeatedly" checked out against laboratory techniques.
  • body weight, postprandial plasma glucose, HbA1c, fasting serum cholesterol and lipids measure bi-weekly  

Independent Variables

  • sucrose or cyclamate periods
  • patients noted in diary frequency and amount of sucrose intake
  • cyclamate tablets and liquids were provided to subjects and intake measured by counting what was left over at the end of the study
  • 3-day dietary monitoring period carried out within each of the diet periods

Control Variables

 

Description of Actual Data Sample:

Initial N: 10; 8 women

Attrition (final N):10

Age: 25-43 yrs

Ethnicity: not specified

Other relevant demographics: duration of diabetes -18 years; on insulin infusion therapy for more than one year; mean HbA1c of 7.5%

Anthropometrics : all had a BMI less than 25

Location: Germany

 

Summary of Results:

 Metabolic control at 4 weeks during each of the three study periods

Variables

Run-in period

Cyclamate Period Sucrose Period Significance

Body weight, kg

67.0±7.6  67.6±8.0

 66.8±7.2

NS

HbA1c

 7.57±0.96

 7.46±0.75

 7.48±0.44

NS

total cholesterol, mmol/l

 5.17±1.16

 5.09±0.80

 5.43±1.09

NS
HDL, mmol/l  1.89±0.52  1.81±0.57

 1.86±0.36

NS
Triglycerides, mmol/l  0.90±0.20  0.93±0.20  0.95±0.30 NS
Random plasma glucose, mmol/l  6.66±4.79  6.60±2.97  5.94±2.86 NS

Other Findings

  • CHO, protein, and fat intake were the same during the three observation periods
  • mean sucrose consumption was 24±13 g/day and mean cyclamate consumption was 10.46±8.09g/day
  • the frequency of blood glucose self-monitoring was significantly higher during the sucrose period

 

Author Conclusion:
A moderate consumption of sucrose may have no adverse effect in normal weight, normolipidemic, near-normoglycemic Type 1 diabetics patients on insulin pump therapy.
Funding Source:
University/Hospital: Dusselldorf University
Reviewer Comments:

Inclusion/exclusion criteria and recruitment methods not well described.

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? ???
  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? No
  2.2. Were criteria applied equally to all study groups? N/A
  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? ???
3. Were study groups comparable? N/A
  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? N/A
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) N/A
  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? ???
  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? 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? ???
  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? No
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? No
  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? ???
  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? N/A
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? No
  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? N/A
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