UWL: Food, Appetite and Environment (2009)

Study Design:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:

The purpose of the research was to determine if a nutritional education program can prevent weight loss in patients with Alzheimer's disease.

Inclusion Criteria:

Patients were included if they:

  • Had a diagnosis of probable Alzheimer's disease according to the NINCDS-ADRDA criteria
  • Lived at home
  • Could be weighed
  • Had a score of between two and six on the Global Deterioration Scale of Reisberg.
Exclusion Criteria:

Patients were excluded if they had intercurrent pathologies.

Description of Study Protocol:


Patients in day-hospitals or in Alzheimer Family Associations of three European cities (Toulouse, France; Brescia, Italy; Mataro, Spain).


Non-randomized, controlled trial.


Nine one-hour nutrition education sessions provided in groups of about 10. The first five sessions were provided during the first month and the remaining four sessions were scheduled for months two, three, six and 12.

Statistical Analysis

Student's T-test or Kruskal-Wallis test for continuous variables, chi-square for categorical variables. Repeated measures ANOVA was used to test the effect of the intervention. Results were adjusted for between-group differences in baseline characteristics.     



Data Collection Summary:

Timing of Measurements

Data were collected at baseline, six and 12 months.

Dependent Variables

  • Monthly weight measured by trained caregivers
  • Nutrition status using the Mini Nutritional Assessment
  • Cognitive function using the Mini Mental State Examination
  • Autonomy using the Activity of Daily Living and Instrumental Activity of Daily Living scales
  • Mood using the Cornell Scale
  • Behavior disorders using the Cohen-Mansfield Agitation Inventory
  • Eating behavior disorders using the Blandford scale
  • Caregiver burden using the Burden Interview
  • Nutritional and AD knowledge at baseline and end in the intervention group.

Independent Variables

Nine sessions of nutrition education provided by a dietitian or other health professional. The sessions included consequences of weight loss, coping with stress, how to use the MNA tool, nutritional and food recommendations, tips to increase intake, eating behavior disorders, practical dietetics, advice based on the MNA results and a final assessment. 

Control Variables

Baseline differences in nutrition status, eating behavior disorders, mood, caregiver age and caregiver burden.

Description of Actual Data Sample:
  • Initial N: 151 patients (52 men and 99 women) and their caregivers in the intervention group and 74 patients (22 men and 52 women) and their caregivers in the control group
  • Attrition (final N): None noted
  • Age:  Mean age of caregivers was 60.5+13.1 in the intervention group and 64.8 in the control group
  • Location: The study was conducted in Spain, France and Italy.
Summary of Results:
Change in Patient Parameters Between Six-month and Baseline (M6-M0), End and Six-month (M12-M6), and End and Baseline (M12-M0)
Before adjustment
After adjustment
* P<0.05, ANOVA with repeated measures between control and intervention.

Other Findings

Differences in caregiver burden were not significant between groups. Caregivers' knowledge of nutrition and Alzheimer's disease increased significantly between the beginning and end of the study.

Author Conclusion:

A one-year nutritional education program could have a positive effect on weight, nutritional status and mood, as well as slow cognitive decline. 

Funding Source:
Reviewer Comments:

Authors note that recruitment procedures may have introduced a sampling bias such that caregivers in the intervention group may have been more receptive to training and more eager to treat eating problems and avoid weight loss; however, patients and caregivers from both groups were very similar.

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? ???
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) N/A
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? No
  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? ???
  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%.) No
  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? ???
  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.) ???
  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? 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? 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? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? No
  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? 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)? Yes
  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