Unintended Weight Loss in Older Adults

UWL: Association With Outcomes (2009)

Citation:

Corbett CF, Crogan NL, Short RA. Using the minimum data set to predict weight loss in nursing home residents. Applied Nursing Research. 2002; 15 (4): 249-253.

PubMed ID: 12444584
 
Study Design:
Longitudinal study.
Class:
C - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:

To investigate the utility of using the minimum data set (MDS) to predict body mass index (BMI) changes in older adults who reside in a nursing home for two or more months. The following questions were specifically investigated:

  • Do older persons with normal or subnormal weight who enter a nursing home and stay two or more months experience a change in BMI?
  • Do items on the MDS completed on admission predict a future change in BMI?
  • Do items on the MDS predict changes in BMI after older persons have lived in the nursing home for more than two months?
Inclusion Criteria:
  • Nursing home resident in one of three homes (size 75 to 150 beds, both non-profit and for-profit institutions)
  • Aged 65 years and older
  • Normal or subnormal weight on admission to nursing home (BMI less than 27kg/m2)
  • Lived at nursing home for at least two months
  • Had at least two MDS assessments completed.

                                                                            

Exclusion Criteria:
  • Overweight on admission to nursing home (BMI more than 27kg/m2)
  • Not a resident of one of the three homes targeted by the study
  • Resident of home for less than two months.
Description of Study Protocol:

Recruitment

All residents in three homes targeted by study were "invited" to participate in the study.

Design

MDS on study participants were collected upon admission by nursing home staff, and again quarterly and anytime a significant change in the participant's condition occurred. Researchers collected the completed MDS data from participants' medical records for a maximum of 14 months or until the participant was discharged from the facility or died.

Statistical Analysis

Descriptive statistics, two-way analysis of variance, backward stepwise linear regression.

Data Collection Summary:

Timing of Measurements

On admission and at least every three months.

Dependent Variables

Change in BMI.

Independent Variables

  • Length of stay in nursing home; the time between the admission MDS assessment and the last available MDS ranged from to to 14 months, with a mean of 8.4±3.9 months.
  • Gender
  • Psychiatric or mood diagnosis
  • Pharmacotherapy for psychiatric or mood diagnosis
  • Functional eating ability.

 

Description of Actual Data Sample:
  • Initial N: The total sample size for three nursing homes was 306. 77 residents met inclusion criteria.
  • Attrition (final N): 77 (13 males, 64 females)
  • Age: 69 to 105 years; mean age was 87±8 years
  • Anthropometrics: On admission, 37 (48%) had a BMI of 22 to 27, and 40 (52%) had a BMI less than 22kg/m2.
Summary of Results:

Other Findings

Overall, residents in the study lost an average of 0.6 lbs over the course of the study; however, change in BMI from the admission MDS to the last MDS assessment included in the study was not statistically significant. No level of statistical significance was reported in the study.

Participants with a psychiatric or mood diagnosis were more likely to have an increase in BMI.

MDS variables shown to predict BMI change:

  • Taking anti-anxiety medications significantly predicted decrease in BMI
  • Leaving 25% or more on their plate at most meals significantly predicted decrease in BMI
  • Ability to eat independently predicted an increase in BMI.

 

 

Author Conclusion:

Three variables from the MDS were significant predictors of weight loss:

  • Leaves 25% or more of food uneaten at most meats
  • Receiving an anti-anxiety medication
  • Not having the ability to feed oneself independently.
Funding Source:
Other:
Reviewer Comments:

Exclusion criteria was not explicit. No demographics were provided on participants. Statistically analysis did not include correlation coefficients and levels of significance. There was no explanation of study limitations in the discussion section.

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) N/A
  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) N/A
 
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? No
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? ???
  2.2. Were criteria applied equally to all study groups? N/A
  2.3. Were health, demographics, and other characteristics of subjects described? No
  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? 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%.) N/A
  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? 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? N/A
  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? N/A
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? N/A
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? N/A
  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? N/A
  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? No
  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? ???
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? ???
  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? No
  7.7. Were the measurements conducted consistently across groups? ???
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? N/A
  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)? N/A
  8.6. Was clinical significance as well as statistical significance reported? No
  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? No
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? No
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