EAL

Weight Management

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

To study the effects of a lifestyle modification programme involving residential stays at a Health and Sport Center on glycemic control and lipid profiles in subjects with diabetes.

Inclusion Criteria:

HbA1c >5%

Exclusion Criteria:

None specifically mentioned.

Description of Study Protocol:

Recruitment: patients were referred for the program after they failed to achieve adequate metabolic control in primary or secondary clinical programs.

Design :

2-week educational program in residence, followed by 8 weeks implementing lifestyle modifications in the home environment
2nd residential visit of 1 weekto help with problems encountered at home; followed by 20 weeks of implementation in the home environment
3rd residential visit of 3 days

Blinding used (if applicable) Not applicable

Intervention (if applicable)

Education program for "persistent lifestyle changes" included these topics at each residential visit

consultation with physician and diabetes nurse
scheduled daily exercise
health profile assessment
dietary advice
stress management
psychological counseling

Statistical Analysis:

changes were analysed by means of a repeated measures ANOVA
subjects were stratified into quartiles based on baseline HbA1c levels

Data Collection Summary:

Timing of Measurements: all variables were measured at each visit

Dependent Variables

HbA1c
body weight
physcial fitness
blood pressure
blood lipids
amount and type of medication
subjects' well-being and total health profile, assessed by interview and questionnaire

Independent Variables

Educational program

Control Variables

HbA1c at baseline

Description of Actual Data Sample:

Initial N:487 subjects

Attrition (final N):

415 (85%) returned for the second residential visit
304 (62%) returned for the third residential visit

Age: mean 54±0.6 y; range 24-77

Ethnicity: not specified

Other relevant demographics: mean HbA1c 7.00-7.30%

Anthropometrics

BMI: 34±0.35

Location: Sweden

Summary of Results:

Variables	Change from visit 1 to visit 2*
	Group 1 (lowest quartile for HbA1c)	Group 2	Group 3	Group 4 (highest quartile for HbA1c)	All subjects
HbA1c, %	-0.33±0.11^de	-0.57±0.10^e	-0.73±0.12^be	-1.42±0.23^bcd	-0.97±0.10^a
Weight, kg	-3.11±0.42	-2.84±0.36	-2.16±0.30	-2.27±0.41	-2.62±0.20 ^a
Predicted maximal O2 uptake (Lmin^-1 kg^-1)	3.74±0.46	3.52±0.71^e	2.38±0.31	2.02±0.42^c	2.91±0.25^a
Systolic blood pressure, mm/Hg	-7.13±1.84	-5.84±1.73	-8.07±2.03	-4.54±1.6	-3.73±0.55
Diastolic blood pressure, mm/Hg	-2.93±1.7^cd	-5.51±0.88^b	-4.9±1.19^b	-3.17±0.95	-4.34±0.55
Total cholesterol,mmol/l	-0.190.11	-0.470.11	-0.200.17	-0.350.11
Triglycerides, mmol/l	-0.360.13	-0.450.17	-0.800.74	-0.740.25
LDL, mmol/L	-0.12±0.12^e	-0.32±0.11^e	-0.09±0.10^e	-0.01±0.10^bcd
HDL, mmol/l	0.06±0.04^e	0.02±0.03^e	-0.01±0.03^e	0.06±0.03^bcd

* Data from visit 3 not included in table because dropout rate at that time exceeded evidence analysis allowances

^a Significant difference from visit 1

^b Significant difference from group 1 (same visit)

^c Significant difference from group 2 (same visit)

^d Significant difference from group 3 (same visit)

^e Significant difference from group 4 (same visit)

Other Findings

Author Conclusion:

A residential lifestyle modification program leads to persistent and significant improvements in HbA1c and blood pressure, and subjects increase their physical fitness and report increased well-being.

Lifestyle modification programs such as the one described in this study are very powerful non-pharmaceutical tools in the reduction of risk factors and in the treatment of patients with diabetes mellitus.

Funding Source:

Reviewer Comments:

By the third visit, the dropout rate increased to 38% in this study. However, we don't know when, during the 20 weeks between those visits, patients dropped out, so that we can't say at what point the dropout rate increased above 20%, the exceeding the amount allowed for inclusion in the evidence analysis for this question.

The selection criteria were stated in very general terms. The subjects had already failed other treatments, so they were likely a non-compliant group. In that case, the 38% dropout rate at visit 3 may not be as unacceptable.

I was left deducing much of the statistical analysis that was performed.

The outcomes were never specifically listed, so I was left to assume that the data they reported reflected their outcomes.

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?	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.)	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?	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?		N/A
	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?	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?	No
	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?	???
	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?	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?	???
	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?		No
	8.1.	Were statistical analyses adequately described and the results reported appropriately?	No
	8.2.	Were correct statistical tests used and assumptions of test not violated?	???
	8.3.	Were statistics reported with levels of significance and/or confidence intervals?	No
	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)?	No
	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