Unintended Weight Loss in Older Adults

UWL: Association With Outcomes (2009)

Citation:

Faxen-Irving G, Basun H, Cederholm T. Nutritional and cognitive relationships and long-term mortality in patients with various dementia disorders. Age Ageing. 2005; 34(2): 136-141.

PubMed ID: 15644407
 
Study Design:
Prospective Cohort Study
Class:
B - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:

To study the nutritional status, short-term effects of adapted nutritional routines and long-term mortality of subjects admitted for cognitive dysfunction. 

Inclusion Criteria:

Patients consecutively admitted for in-ward investigation of cognitive function between October 1994 and June 1996.

Exclusion Criteria:

Not discussed.

Description of Study Protocol:

Recruitment

Patients referred to the clinic from their general practitioner and were considered not capable of being examined as outpatients.

Design

Prospective cohort study.

Intervention

  • Nutrition regime in the ward consisting of: Breakfast between 8:00 A.M. and 10:00 A.M., lunch at 12:00 noon, dinner at 5:00 P.M., afternoon coffee at 2:00 P.M. and an evening meal at 7:00 P.M. in a home-like dining room
  • Food was served on china, patients served themselves when possible, whole fat milk and spread were offered, cream-fortified desserts were used at lunch and dinner, homemade buns and pastries were served in the afternoon and low-calorie products were not used.

Statistical Analysis

Data presented as mean ± SD or median. Data was analyzed using one-way analysis of variance by ranks, chi-squared test, least significant difference post-hoc test, paired T-test, Wilcoxon sign rank test, correlation coefficients, multiple regression analysis and logistic regression.

Data Collection Summary:

Timing of Measurements

Nutrition and cognitive status was measured at admission and discharge from the facility. Mortality was measured after seven years.

Dependent Variables

  • Mortality measured by public records
  • BMI
  • Serum concentration of albumin
  • Serum concentration of ferritin
  • Serum concentration of vitamin B12
  • Serum concentration of folic acid
  • Serum concentration of hemoglobin
  • Mental status was measured by Mini-Mental State Examination results 
  • Comorbidity was categorized into nine diagnostic groups and assessed as mild or severe.

Independent Variables

Facility nutritional regime.

 

 

Description of Actual Data Sample:
  • Initial N: 231, 65% female
  • Attrition (final N): 231 subjects
  • Age: 80±7 years at start of the study
  • Anthropometrics: Dementia diagnoses were classified as Alzheimer's dementia, vascular dementia, mixed dementia, mild cognitive impairment, other and mixed
  • Location: Patients from Southwest Stockholm admitted to University Hospital.
Summary of Results:

 Results of Nutritional Status Measurements from Admission to Discharge

  Change P-value
Weight increased 0.007
BMI increased not reported
MMSE increased <0.001

Serum albumin

increased not reported
Serum  Vitamin B12 increased 0.018
Serum ferritin decreased not reported

Other Findings:

  • Mean BMI was in the normal range (23.3±4) as were the biochemical indices, and they did not vary among patients with Alzheimer's disease, vascular dementia, mild cognitive impairment, mixed dementia and other diagnoses
  • A BMI of less than 23 was found in 108 (52%) subjects
  • Weight and MMSE score correlated weakly (R=0.18, P<0.01) at inclusion
  • During a median hospital stay of three weeks, an average weight gain of 0.5±1.8kg (P<0.001) and an increase in MMSE score of 0.9±3 (P<0.001) was observed. However, these changes did not correlate. 
  • During the seven-year observation period, 191 patients (83%) died, with a median survival of three years and seven months
  • There was no difference in the mortality rate between various dementia groups except those with "other dementia disorders" had higher mortality of 89% with P=0.15
  • Weight gain during the hospital stay tended to predict a better seven-year survival (P=0.08)
  • Those with severe comorbidities has shorter survival rates than those with no or mild comorbidities (P<0.0001)
  • Patients with BMI of less than 23 showed higher long-term mortality (P=0.002)
  • After seven years, a quarter of the individuals with BMI of 23 or more were still alive and 10% of those with a BMI of less than 23 were
  • BMI less than 23 remained a predictor of seven-year mortality even after adjustment for age, male gender and severe comorbidity (OR, three; 95% CI=1.3 to 6.7).

 

 

Author Conclusion:

At admission, there was a correlation between weight and MMSE, but after the three-week observation, there was no correlation in the change in MMSE and change in weight. When changes during the hospital stay were recorded, weight gain over the three-week period was most evident in patients with Alzheimer's dementia and vascular dementia, and subjects with BMI less than 22 at the start gained more weight than those with a BMI of 22 or higher. At a seven-year follow-up, a BMI of 23 or higher was found to be associated with an increased survival rate, independent of age, male gender and comorbidity with median survival rate of 3.6 years. 

Funding Source:
Government: Swedish Research Council, Stockholm City Council
University/Hospital: Karolinska Institute
Reviewer Comments:

No exclusion criteria were provided. There may have been some patients that were admitted to the hospital, but were not included in the study. Also, all patients were provided with the nutritional ward regimen, but no information about their individual food acceptance of the nutritional regimen was mentioned.

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? ???
  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? N/A
  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? N/A
  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? ???
  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%.) N/A
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? ???
  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? 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? No
  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? No
  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? ???
  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