GDM: Pharmacologic Therapy (2008)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
The purpose of the study was to assess maternal and fetal outcomes in pregnant women who used lispro insulin as their short-acting insulin along with isophane insulin in a twice-daily (free-mixed) or basal bolus regimen, compared to outcomes in women using regular insulin in similar regimens.
Inclusion Criteria:

Women with gestational diabetes followed by the Preston Acute Hospital NHS Trust in the United Kingdom.

Exclusion Criteria:
None stated.
Description of Study Protocol:

Recruitment

Pregnanies were identified by the hospital database. Women with gestational and pre-gestational diabetes followed by the Preston Acute Hospital NHS Trust in northwest UK for the last 7 years. Women with either gestational or pre-gestational diabetes who received regular insulin in one pregnancy and lispro in the other were recruited for the Diabetes Treatment Satisfaction Questionnaire.

Design

Pregnancies were divided into 3 groups: managed by diet only, manged with regular insulin as their short acting insulin, or managed with lispro as their short acting insulin. Maternal and fetal characteristics, fetal outcomes and congenital anomalies were compared. Satisfaction survey scores were compared between those groups who had used regular and lispro insulin in successive pregnancies.

Blinding used (if applicable):  Not applicable

Intervention (if applicable)

The effects of lispro versus regular insulin on maternal characteristics and fetal outcomes and on maternal satisfaction.

Statistical Analysis

Unpaired and paired two-tailed Students' t test and Fisher's exact test were used. p<0.05 was considered significant

 

Data Collection Summary:

Timing of Measurements

Maternal HbA1c was measured predelivery, babies were evaluated at birth.

Dependent Variables

  • Maternal outcome - measured by pregnancy loss, HbA1c pre-delivery, and Casesarean section delivery
  • Fetal outcome - measured by mean gestational age, birth weight, % with hypoglycemia at birth, % with hyperbilirubinaemia at birth
  • Congenital anomalies
  • Patient satisfaction with lispro versus regular insulin

Independent Variables

  • Women with gestational diabetes who used diet, regular or lispro insulin
  • Women with pregestional diabetes who used regular or lispro as their short acting insulin

Control Variables

 

Description of Actual Data Sample:

Initial N: 635 pregnancies with gestational and pre-gestational diabetes managed by the unit

Attrition (final N):  538 with gestational diabetes mellitus (325 managed with diet only, 138 with regular insulin and 75 with lispro insulin) and 70 with pre-gestational diabetes mellitus

Age: Age range of all patients was 17- 41 years

Ethnicity: None stated

Other relevant demographics: None available

Anthropometrics:  538 women with gestational diabetes mellitus, 70 with pre-gestational diabetes

Location: Northwest United Kingdom

Summary of Results:

 Maternal details

 

Gestational DM

Diet

Gestational DM

Regular

Gestational DM

Lispro

 

Diabetes Mellitus

Regular

Diabetes Mellitus

Lispro

Pregnancy loss (%)

0.61

0

0

18.6

3.7

HbA1c pre-delivery (mean + SD)

6.01+  0.80

 6.08 + 0.68

 5.8 + 0.40

 6.86  +0.40

6.80 + 0.61

Caesarean section delivery (%)

 23

 25

 32

 46

 60

Details of babies 

        

Gestational DM

Diet

Gestational DM

Regular

Gestational DM

Lispro

DM

Regular

DM

Lispro

Mean gestational age (weeks) 38.5 38.1 37.4 36.5 37.4
Birth weight (kg) (mean + SD) 3.41+  0.57 3.31 + 0.58 3.29  +0.57 3.26  +0.81 3.27  +1.04
Babies (n) 326 138 76 57 26
Hypoglycemia (%) 13 30 17 19 20
Hyperbilirubinaemia (%) 17 17 28 23 40

Congenital anomalies

 

Gestational DM

Diet

Gestational DM

Regular

Gestational DM

Lispro

DM

Regular

DM

Lispro

Pregnancies with live-birth (n) 323 138 75 57 26
Babies (n) 326 138 76 57 26
Total Anomalies (%) 17 (5.2) 11 (7.9) 5 (6.6) 9 (15.8) 1 (3.8)
Major Anomalies (%) 6 (1.8) 3 (2.2) 1 (1.3) 4 (7.0) 0 (0)
Minor Anomalies (%) 11 (3.4) 8 (5.7) 4 (5.3) 5 (8.8) 1 (3.8)

Other findings:                         Regular insulin         Lispro insulin

DTSQ score  (mean + SD)            18 + 8.9                   26.3 + 2.3 **

** p = 0.0005

 

 
Author Conclusion:
We observed no increase in adverse fetal or maternal outcomes with the use of lispro insulin. Lispro insulin is viewed as more satisfactory than regular insulin in patients with gestational diabetes mellitus.
Funding Source:
Reviewer Comments:

Not much detail on the DTSQ score or what a high versus low score means.

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? ???
  2.4. Were the subjects/patients a representative sample of the relevant population? ???
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) N/A
  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.) 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? ???
  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? ???
  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.) N/A
  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? ???
  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? ???
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? ???
  6.6. Were extra or unplanned treatments described? ???
  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? ???
  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? ???
  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)? N/A
  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