EAL

DM: Effectiveness of MNT Provided by RD/RDN (2015)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

To evaluate whether a course teaching flexible intensive insulin treatment combining dietary freedom and insulin adjustment can imrove both glycemic control and quality of life in type 1 diabetes.

Inclusion Criteria:

Age above 18 years
Clinical features of type 1 diabetes
HbA1c 7.5-12%
Duration of diabetes over two years without advanced complications.

Exclusion Criteria:

Inability to understand written and spoken English
Severe psychiatric illness
Pregnancy
Complete unawareness of hypoglycemia.

Description of Study Protocol:

Recruitment

Single invitation letter sent to all patients identified from clinic registers as fulfilling inclusion criteria
Subjects recruited from diabetes clinics in three hospitals.

Design

Volunteers randomized into a waiting list controlled trial
- Immediate DAFNE: Attend a five-day training course delivered in groups of six-eight participants
- Delayed DAFNE: Continue to receive usual care for six months and then attend the course.
After participating in a course, the participants returned to their usual clinic and were not offered specific follow-up.

Blinding Used

Not applicable.

Intervention

Five-day course taught Monday through Friday by diabetes nurse specialists and dietitians
Participants were intended to acquire the skills and confidence to adjust insulin to suit their lifestyle rather than being told to adapt the timing and content of their meals to fixed doses of insulin
Educators attended a training session run by university faculty
Appraisers visited one course in each center to ensure that the course was taught to high standards and was similar between centers
Courses were peer-reviewed by educators from other centers.

Statistical Analysis

Study had 80% power to detect a 1% difference in HbA1c in a sample of 120 patients
Outcomes at six months were compared using unpaired T-tests
Data checked for normality and skewed variables were transformed using square root, log and inverse transformations, where appropriate
Chi-square test used to compare the proportions of patients experiencing severe hypoglycemia in the two groups at six months and 12 months
Paired T-tests performed with baseline and 12-month data.

Data Collection Summary:

Timing of Measurements

Immediate DAFNE group
- Baseline assessment two weeks pre-course
- Follow-Up One at six months post-course
- Follow-Up Two at 12 months post-course.
Delayed DAFNE group
- Baseline assessment at six months pre-course
- Follow-Up One at two weeks pre-course
- Follow-Up Two at six months post-course.

Dependent Variables

HbA1c, using HPLC
Severe hypoglycemic episodes
Quality of life, using audit of diabetes-dependent quality of life (ADDQoL) questionnaire
Satisfaction with treatment using the diabetes treatment satisfaction questionnaire (DTSQ)
Weight
Blood pressure
Serum lipids
Number of insulin injections, total insulin dose and blood glucose monitoring.

Independent Variables

Immediate or delayed DAFNE group.

Description of Actual Data Sample:

Initial N

Invitations sent to 1,016 addresses and 423 were returned; 74% expressed interest in the study
Of these, 138 attended an evening meeting, of whom 128 (93%) decided to partcipate
Another 41 were recruited without attending a meeting
169 subjects randomized.

Attrition (final N)

69 completed immediate DAFNE; 72 completed delayed DAFNE
136 subjects were followed up according to schedule.

Age

40±9 years.

Ethnicity

Not specified.

Other Relevant Demographics

Mean duration of diabetes was 16.6±9.6 years
56% of participants were women
52 patients had retinopathy; 19 had peripheral neuropathy; two had nephropathy.

Anthropometrics

No significant differences between groups at baseline.

Location

United Kingdom.

Summary of Results:

Variables	Immediate DAFNE Measures and Confidence Intervals		Delayed DAFNE
	Baseline	Six months	Baseline	Six months
HbA1c, percentage	9.4 (1.2)	8.4 (1.2)	9.3 (1.1)	9.4 (1.3)
Percentage of participants experiencing severe hypoglycemia in the previous six months	22	18	11	15
Weight, kg	80.5 (16.7)	81.5 (16.9)	77.4 (13.4)	77.3 (13.4)
Total cholesterol, mmol/L	5.2 (0.9)	5.1 (0.9)	4.9 (0.8)	5.0 (1.0)
HDL, mmol/L	1.5 (0.4)	1.6 (0.4)	1.5 (0.5)	1.5 (0.3)
Triglycerides, mmol/L	1.5 (0.9)	1.4 (0.7 )	1.5 (0.9)	1.5 (0.9)

Variable	Mean Difference Between Groups at Six Months, (95% CI)	P-value
HbA1c, percentage	1.0 (0.5 to 1.4)	P<0.0001
Percentage of participants experiencing severe hypoglycemia in previous six months	-	P=0.68
Weighted impact of diabetes on "freedom to eat as I wish"	2.2 (1.3 to 3.1)	P<0.0001
Average weighted impact of diabetes on quality of life	0.4 (-0.1 to 0.9)	P<0.01
Present quality of life	0.3 (-0.1 to 0.6)	P=0.095
Total wellbeing	2.98 (1.06 to 4.89)	P<0.01
Total satisfaction	8.75 (7.02 to 10.48)	P<0.0001
Perceived frequency of hyperglycemia	-1.13 (-1.59 to -0.67)	P<0.0001
Perceived frequency of hypoglycemia	-0.23 (-0.68 to 0.21)	P=0.31
Weight, kg	4.18 (-0.90 to 9.27)	P=0.11
Total cholesterol, mmol/L	0.15 (-0.16 to 0.45)	P=0.34
HDL, mmol/L	0.09 (-0.01 to 0.22)	P=0.14
Triglycerides, mmol/L	0.12 (-0.14 to 0.17)	P=0.41

Other Findings

Twelve months after training the immediate DAFNE group HbA1c remained significantly improved, compared with baseline (mean difference 0.5%, P=0.001).

Author Conclusion:

The DAFNE training significantly improved hyperglycemia with no significant increase in severe hypoglycemia
The training produced sustained positive effects on quality of life, satisfaction with treatment and psychological wellbeing, despite an increase in number of insulin injections and encouragement to increase blood glucose monitoring
Despite increased dietary freedom, there was no deterioration in CVD risk factors
People with established diabetes, when taught appropriate skills, will intensify management of their diabetes and that this can be associated with improved quality of life.

Funding Source:

Reviewer Comments:

Dietary intake was not assessed in this study; there was an implicit assumption that more carbohydrates would be consumed by subjects.

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?		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?	No
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	N/A
	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?	N/A
	7.3.	Was the period of follow-up long enough for important outcome(s) to occur?	N/A
	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)?	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?	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