Unintended Weight Loss in Older Adults

UWL: Nutritional Status (2009)

Citation:

Nakamura H, Fukushima H, Miwa Y, Shiraki M, Gomi I, Saito M, Mawatari K, Kobayashi H, Kato M, Moriwaki H. A longitudinal study on the nutritional state of elderly women at a nursing home in Japan. Intern Med. 2006; 45(20): 1,113-1,120.

PubMed ID: 17106153
 
Study Design:
Panel design.
Class:
C - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:
  • To evaluate the nutritional state of elderly individuals at a nursing home by measuring anthropometry, MRI, serum albumin level, and plasma amino acid profiles over a three-year period
  • To identify the baseline factors affecting the nutritional state of elderly individuals.
Inclusion Criteria:
  • Elderly women
  • None specifically mentioned.
Exclusion Criteria:
  • None had malignant disease
  • No subject used a feeding tube or total parenteral nutrition during the study period
  • None specifically mentioned.
Description of Study Protocol:

Recruitment

Elderly women recruited from a nursing home in Japan. Recruitment methods were not described.

Design

Longitudinal study. 

Intervention

  • Activities of daily living were measured at baseline
  • Measurements of nutritional status were measured over three years.

Statistical Analysis

  • Differences in the incidence or mean values between groups A and B were tested by the Chi-square test or Mann-Whitney U test
  • Changes over the years in the anthopometric parameters, thigh muscle volume, thigh fat volume, serum albumin level and plasma amino acid concentration were tested by a repeated measures ANOVA followed by the Fisher's PLD test
  • Changes in thigh muscle volume, percentage arm muscle circumference and the serum albumin level within and between groups A and B were also tested by repeated measures ANOVA.
Data Collection Summary:

Timing of Measurements

Activities of daily living were measured at study entry. Nutritional status parameters were measured every year from 2000 to 2003.

Dependent Variables

  • Anthropometry measures included height, weight, BMI, arm circumference, arm muscle circumference, calf circumference and thigh circumference and were compared to age- and sex-matched reference values for Japanese
  • Thigh muscle volume and thigh fat volume were measured through MRI
  • Fasting blood samples were analyzed for serum albumin and plasma amino acid levels.

Independent Variables

  • Activities of daily living measured through Barthel Index at entry
  • Seven women belonged to Group A (Barthel Index score 65 to 100), implying mild or no decline in ADL
  • Nine women belonged to Group B (Barthel Index score zero to 60), demonstrating severe decline in ADL.

 

Description of Actual Data Sample:
  • Initial N: 16 elderly women. The original inclusion of men is mentioned in the Discussion.
  • Attrition (final N): 16 women
  • Age: Mean age 83±7 years (range 67 to 93 years)
  • Ethnicity: Japanese
  • Location: Central Japan.
Summary of Results:

 Time Courses of Changes in Each Nutritional Parameter in Three Years

Variables

Baseline Year One Year Two Year Three

Body Weight (kg)

41.2±8.5 40.9±7.1 40.7±6.6 40.2±7.3
BMI 21.0±3.7 20.8±2.9 20.7±2.8 20.5±3.0
Percentage, arm circumference 102.8±13.7 97.9±11.5 95.6±12.4 94.8±12.6
Percentage, arm muscle circumference 107.7±11.4 102.4±10.5 100.6±11.0 98.8±10.5, P<0.05
Percentage, triceps skinfold thickness 84.0±34.1 81.6±25.8 75.8±27.8 80.2±34.0
Percentage calf circumference 96.2±9.4 96.2±10.0 93.7±8.7 92.5±8.2
Thigh circumference (cm) 37.5±5.3 36.6±4.5 36.4±4.4 36.3±4.3
Thigh muscle volume (cm3) 1,872±240 1,834±261 1,749±222 1,670±221, P<0.05
Thigh fat volume (cm3) 2,732±945 2,639±918 2,475±774 2,517±835
TMV/TFV 0.77±0.30 0.78±0.30 0.77±0.25 0.74±0.31

Serum albumin (g per dL)

4.19±0.28

3.96±0.47

3.91±0.42

3.74±0.44, P<0.05

Total amino acids (nmol per ml) 3,113.6±290.6  3,162.0±420.7 3,017.4±448.8 2,793.4±329.2, P<0.05
Essential amino acids (nmol per ml) 939.3±102.0 947.2±156.3 908.1±157.7 766.6±98.4, P<0.05
Branched chain amino acids (nmol per ml) 401.3±50.3 392.1±95.8 387.3±87.1 308.1±50.9, P<0.05
Fischer's ratio 2.89±0.27 2.83±0.26 2.61±0.26, P<0.01 2.66±0.39, P<0.05

Other Findings

  • In all subjects, the thigh muscle volume, percentage of arm muscle circumference and serum albumin level decreased significantly during the three-year period (P<0.05, respectively)
  • The change in thigh muscle volume correlated significantly with those in the percentage of arm circumference and percentage of arm muscle circumference (P<0.05, respectively)
  • Group B showed significantly larger decreases in the percentage of arm muscle circumference and serum albumin level than group A. 
Author Conclusion:

In conclusion, the longitudinal decline in muscle volume (sarcopenia) and serum albumin level was associated with aging and ADL level. The nursing home subjects, particularly those with low ADL level, can easily develop protein energy malnutrition, which leads to worse morbidity and mortality. Special nutritional support should thus be provided to elderly individuals to allow them to maintain their ADL levels as well as to improve their overall health condition.

Funding Source:
Other: Not described
Reviewer Comments:

Recruitment methods and inclusion and exclusion criteria were not well defined. Small sample size. Men were originally included in the study, but details were not provided. Authors note the following limitations:

  • Lack of information on the precise nutritional intake, particularly the protein intake of the participants
  • Information on the background of chronic diseases was obtained only by interviews
  • Data focused only on female 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? ???
  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? ???
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? ???
  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%.) ???
  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? Yes
  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.) 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? 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? ???
  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? No
  7.7. Were the measurements conducted consistently across groups? N/A
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)? N/A
  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? No
  10.2. Was the study free from apparent conflict of interest? Yes