DM: Carbohydrate Management Strategies (2014)


Franc S, Dardari D, Boucherie B, Riveline JP, Biedzinski M, Petit C, Requeda E, Leurent P, Varroud-Vial M, Hochberg G, Charpentier G. Real-life application and validation of flexible intensive insulin-therapy algorithms in type 1 diabetes patients. Diabetes Metab. 2009; 35(6): 463-468.

PubMed ID: 19914853
Study Design:
Time Study
C - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:

To confirm that the use of personalized algorithms with FIT results in good control of the post-prandial state in type 1 diabetic patients.

Inclusion Criteria:
  • Willingness to participate in the study 
  • Clinical diagnosis of type 1 diabetes
  • Duration of diabetes of more than one year
  • Use of the FIT strategy for at least six months
  • Took a five-day structured inpatient training program on FIT at least six months prior to entering the study
  • Provided written informed consent.
Exclusion Criteria:
Not described.
Description of Study Protocol:


A total of 35 patients who attended the Diabetes Department of the Sud-Francilien Hospital were recruited.


Time study.

Blinding Used

Implied with measurements.


  • Personalized prandial algorithms for FIT as proposed by Howorka et al
  • Patients self-monitored their own blood glucose using glucometers that were validated for accuracy against the local laboratory reference method at each visit.
Statistical Analysis
  • SPSS version 14.0 was used and results are reported as means ±SD
  • Paired student's T-tests were used for estimating significant differences vs. baseline values
  • Mean blood glucose values were compared across different patient sub-groups using analysis of variance (one-way ANOVA) and correlation tests of quantitative data were performed using Pearson's coefficient.
Data Collection Summary:

Timing of Measurements

Measurements taken daily throughout the four-month study.

Dependent Variables

  • FBG, 2h-PPBG and L-FBG
  • Number of CHO portions and insulin units at each meal
  • Metabolic control was assessed by HbA1c by high-performance chromatography
  • The main safety criterion was the occurrence of hypoglycemic events where major events were defined as those requiring external assistance, while minor events were defined as BG values less than 3mmol per L. All events were recorded in an electronic diary.
Independent Variables

Personalized prandial algorithms for FIT as proposed by Howorka et al:
  • Patients self-monitored their own blood glucose using glucometers that were validated for accuracy against the local laboratory reference method at each visit
  • Self-monitoring of blood glucose values was recommended to be done six times a day [before and two hours after the beginning of each meal (2h-PPBG) and occasionally at around 3:00 a.m.]
  • The data was transmitted via the PDA’s general packet radio service (GPRS) network to a secure website where they were collected for the analysis
  • The site also allowed caregivers to follow the patients' results at all times and to contact the patients by telephone to offer more information and advice.
Description of Actual Data Sample:
  • Initial N: 35 patients (23 males, 12 females)
  • Attrition (final N): 29 subjects completed the four-month study.
  • Age: 39.1±10.8 years 
  • Other relevant demographics: Mean duration of diabetes was 18.8±11.1 years
  • Anthropometrics: Body mass index 25.1±3.5 kg/m2
  • Location: France.
Summary of Results:

Key Findings

  • Mean post-prandial blood glucose values remained close to the target of 7.8mmol per L and the compensatory algorithm allowed precise correction of pre-prandial hyperglycemia
  • The mean fasting blood glucose value was 8.0±3.6mmol per L at breakfast, 7.3±3.3mmol per L at lunch and 8.5±3.8mmol per L at dinner
  • According to Howorka's calculations, 2.3±0.8 insulin units were necessary to metabolize one 20g CHO portion; at the end of the study, the mean ±SD prandial algorithm was 2.5±1.2U per P at breakfast, 2.4±0.9U per P at lunch and 2.4±0.9U per P at dinner. There were no statistically significant differences between the initial and final algorithms.
  • Regarding correctional insulin use, 3.8±1.8 insulin units were necessary to reduce blood glucose values by 5.55mmol per L. There were no differences in mean correctional insulin doses at the end of the study vs. baseline.
  • The algorithms for meal-related and correctional insulin doses at the end of the study did not differ significantly from those initially calculated, but they generally differed from one patient to the other
  • The mean HbA1c value was significantly lower at the end of the study than at the initial visit (7.3±0.6% vs. 7.8±0.9%; P=0.003).



Author Conclusion:

In type 1 diabetic patients treated with FIT, the use of individualized parameters permits fast and accurate adjustment of mealtime insulin doses, leading to good control of the post-prandial state.

Funding Source:
Grant from ALFEDIAM Sanofi-Aventis 2006
Pharmaceutical/Dietary Supplement Company:
Reviewer Comments:

Limitations to this study:

  • It was an open-label, single center study involving only a small number of type 1 diabetic patients
  • There was no control group.
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? 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? No
  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? No
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? 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%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? Yes
  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? No
  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? 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? Yes
  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? 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? Yes
  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? 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)? 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? Yes
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