EAL

PDM: Prediabetes (2013)

Citation:

Parikh P, Simon EP, Fei K, Looker H, Goytia C, Horowitz CR. Results of a pilot diabetes prevention program intervention in East Harlem, New York City: Project HEED. Am J Public Health. 2010; 100 Suppl 1: S232-S239.

PubMed ID: 20147680

Study Design:

Randomized Controlled Trial

Class:

A - Click here for explanation of classification scheme.

Quality Rating:

NEUTRAL: See Quality Criteria Checklist below.

Research Purpose:

To test a simple, peer-led intervention to promote weight loss, which can prevent diabetes and eliminate racial and ethnic disparities in incident diabetes among overweight adults with prediabetes (defined as impaired fasting glucose of 100 to 125mg per dL or impaired glucose tolerance of 140 to 199mg per dL after a 75g glucose load).

Inclusion Criteria:

Age 18 or older
Resided in East Harlem, NY
Spoke English or Spanish
Overweight as measured by BMI 25kg/m² or more
Not currently pregnant
Did not have diabetes
Did not use glucose-altering medications
Able to participate in a group session
Provided written informed consent
Asked to return while fasting for an oral glucose tolerance test on another morning.

Exclusion Criteria:

Not described.

Description of Study Protocol:

Recruitment

Recruitment occurred in two phases between May and July 2007
Members of the board and study personnel recruited at community sites and events such as churches, social service agencies, senior centers and health fairs

Design

Randomized controlled trial (pilot study).

Blinding Used

Implied with measurements.

Intervention

Participants were randomized to intervention or delayed intervention (in one year by blocked randomization) by recruitment site
Intervention participants attended the workshop at the community sites often where recruitment occurred
Project HEED’s curriculum followed self-efficacy theory and contained simple, actionable messages that was easily taught by lay leaders and focused on enhancing self-efficacy to make lifestyle changes
It was presented in a workshop consisting of eight 1.5-hour sessions over 10 weeks
Topics included diabetes prevention, finding and affording healthy foods, label reading, fun physical activity, planning a healthy plate, making traditional foods healthy and portion control
The intervention group received brief verbal and written information about prediabetes and results of all their screening tests, with a copy to take home that they could also share with their clinicians.

Statistical Analysis

Intent-to-treat analysis with weight as the primary outcome
Compared participants' self-reported demographic characteristics at baseline and performed bivariate comparisons with T-tests, X² tests and analysis of variance
Changes in participants weights and behaviors between baseline and 12 months with paired T-tests
SAS version 9.1.3 was used and statistical significance was set at 0.05.

Data Collection Summary:

Timing of Measurements

Measurements made at baseline and repeated at three, six and 12 months after enrollment.

Dependent Variables

Finger sticks were done to obtain fasting glucose levels measured with Accuchek glucometers
Participants with non-diabetes glucose levels (less than 126mg per dL) drank a 75g glucose load and had a finger stick two hours later
Trained staff measured weight without shoes in the morning while fasting with a Siltec scale
Blood pressure in the non-primary arm and waist circumference (one inch above the umbilicus) were measured twice and the readings averaged
Venous blood was drawn for hemoglobin A1c and serum cholesterol levels.

Independent Variables

Participants were randomized to intervention or delayed intervention (in one year by blocked randomization) by recruitment site
Intervention participants attended the workshop at community sites, often where recruitment occurred
Project HEED’s curriculum followed self-efficacy theory and contained simple, actionable messages that was easily taught by lay leaders and focused on enhancing self-efficacy to make lifestyle changes
It was presented in a workshop consisting of eight 1.5-hour sessions over 10 weeks
Topics included diabetes prevention, finding and affording healthy foods, label reading, fun physical activity, planning a healthy plate, making traditional foods healthy and portion control
The intervention group received brief verbal and written information about prediabetes and results of all their screening tests, with a copy to take home that they could also share with their clinicians.

Description of Actual Data Sample:

Initial N: 99 participants at baseline (85 females); 50 in the intervention group, 49 in the control group
Attrition (final N): 83 participants returned at three months, 79 at six months, and 72 at 12 months (37 control, 35 intervention)
Age: Mean age 48 years (range 25 to 84)
Ethnicity: 89% Hispanic
Other relevant demographics: Mean HbA1c level was 5.6
Anthropometrics: 56% obese (BMI range 30 to 39kg/m²). There were no statistically significant differences between the intervention and control participants at baseline in demographic characteristics, anthropometric measures or behaviors except that intervention participants drank significantly more juice (P=0.04)
Location: East Harlem, NY.

Summary of Results:

Key Findings

The intervention group lost significantly more weight than did the control group and maintained the weight loss at 12 months (-7.2±7.3 vs. -2.4±8.1 lb.; P<0.01)
In addition, the intervention group had a significant reduction in waist circumference (-1.3±2.6 vs. +0.1±3.4cm; P=0.05)
However, there were no significant differences between groups in terms of fasting glucose, hemoglobin A1C or systolic and diastolic blood pressure
Although intervention participants achieved significant and sustained weight loss they reported very limited behavior changes
Self-reported physical activity did not differ between the two groups
One-fourth (24 of 99 participants) progressed to diabetes.

Author Conclusion:

In underserved minority communities, prediabetes prevalence may be higher and low-cost, community based interventions can succeed in encouraging weight loss to prevent diabetes.

Funding Source:

Government:	New York State Department of Health Diabetes Prevention and Control Programs
Other:	National Center on Minority Health and Health Disparities grant

Reviewer Comments:

Noted limitations.

A vulnerable cohort mostly composed of low-income, undereducated and medically underserved Hispanic immigrants were recruited and this population is difficult to engage in research
The sample size after one year of follow-up was too small (N=72).

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?	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?	No
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?		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?	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?	Yes
	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)?	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?	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