Unintended Weight Loss in Older Adults

UWL: Nutritional Status (2009)

Citation:

Bowman JJ, Keller HH. Assessing nutritional risk of long-term care residents. Can J Diet Prac Res. 2005; 66: 155-161. 

PubMed ID: 16159408
 
Study Design:
Cross-Sectional Study
Class:
D - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:

To evaluate the Minimum Data Set (MDS) 2.0 oral and nutrition status (Section K) items, used to identify long-term care residents at nutritional risk. The following were evaluated in the current study:

  • The validity of single items
  • The recommended trigger system
  • Combinations of variables from the MDS 2.0 Section K compared with clinical judgment in determining nutritional risk.
Inclusion Criteria:

None specifically mentioned.

Exclusion Criteria:

None specifically mentioned.

Description of Study Protocol:

Recruitment

All residents occupying a continuing care unit or nursing home bed in St. Joseph's Hospital and Home in Guelph, Ontario were invited to participate in this study.

Design

Cross-sectional study. 

Blinding Used

The dietitian performing the assessments and rating was blinded to data from the MDS appraisal.

Statistical Analysis

  • Bivariate tests of association (T-tests, correlation and analysis of variance) were used to assess the relationship between the dietitian rating and each Section K item
  • The sensitivity and specificity of specific and combinations of variables were also determined at a cut point at or above five, indicative of a moderate or higher level of nutritional risk
  • To determine the precision of the sensitivity and specificity estimates in the sample population, the 95% confidence interval based on the standard error of the estimate was considered.  
Data Collection Summary:

Timing of Measurements

Participants underwent a comprehensive nutritional assessment, which included a review of their medical chart for weight, medical history, diagnoses, problems and medication use.

Dependent Variables

Nutritional risk.

Independent Variables

  • Registered Dietitian assessed residents using standardized procedures and used clinical judgment to provide a nutritional risk rating. Measurements included weight, triceps and subscapular skinfold measurements; knee-height measurement; and wrist, calf and mid-upper-arm circumference measurements, as well as an observation of eating during one random meal period
  • Registered nurses completed the MDS assessments
  • Biochemical indicators included serum cholesterol level, albumin and hemoglobin testing, hematocrit and total lymphocyte count.

 

Description of Actual Data Sample:
  • Initial N: 215 residents in St. Joseph's Hospital and Home invited to participate
  • Attrition (final N): 129 (60%) agreed to participate. One died, resulting in 128 residents. 47% female in the CCU, 63% female in the nursing home.
  • Age: 68.4±18.0 in the CCU, 80.8±11.3 in the nursing home
  • Location: Guelph, Ontario, Canada.
Summary of Results:

Descriptive and Bivariate Analysis of MDS Characteristics Compared with Dietitian Risk Rating

MDS Variable

Percentage Mean Nutritional Risk Rating T-test P-value

Presence of chewing problem

30% 6.2±1.74  -0.340  0.735 
Presence of swallowing problem 23%  6.7±1.83  -2.013  0.046
Presence of mouth pain 2%  4.7±2.52  1.391  0.167 
Presence of weight loss 2%  7.7±0.58  -1.470  0.144 
Presence of weight gain 2%  4.7±3.21  1.365  0.175 

Presence of complaints about taste

6% 6.1±2.19  -0.026  0.979 
Presence of complaints about hunger 2%  7.5±0.71  -1.063  0.290 
Presence of 25% of food left uneaten 12%  6.7±2.05  -1.364  0.175 
Presence of PN, EN, mechanical or syringe diet 37%  7.0±1.48  -4.249  0.000 
Presence of therapeutic diet 13% 6.2±1.33  -0.144  0.885 
Presence of supplement between meals 45%  6.6±1.63  -2.862  0.005 

Presence of feeding device

9% 

6.2±1.94 

-0.106 

0.915 
Presence of being on a planned weight change program 10%  5.5±1.56  1.373  0.172 
Presence of BMI less than 24 51%  6.7±1.68  -3.751  0.000 
Presence of BMI less than 20 28%  7.1±1.59  -3.845  0.000 

Other Findings

  • The Registered Dietitian's assessment revealed a mean overall nutritional risk rating of 6.1±1.8, indicative of moderate risk
  • 15.7% of the study participants were classified as being at a low level of nutritional risk (rating less than five), 60.9% were classified as being at moderate risk (rating five, six or seven) and 23.4% were classified as being at high risk (rating more than seven)
  • The most frequent nutritional indicators were supplement use between meals (44.5%), a diet prescription for parenteral nutrition or enteral nutrition, a mechanical diet or syringe feeding (36.7%), a chewing problem (29.7%) and a swallowing problem (22.7%)
  • The MDS variables of dietary prescription (T=-4.249, P<0.001), supplement use (T=-2.862, P<0.01) and swallowing problems (T=-2.013, P<0.05) were significantly associated with nutritional risk rating
  • Participants who had lost weight had a higher mean risk rating than those who had not, and those who had gained weight had a lower mean risk rating than those who had not
  • BMI, calculated from MDS data, also was significantly associated with nutritional risk rating (P<0.001)
  • The MDS trigger system, however, had poor sensitivity and specificity
  • The best combination of variables included the presence of one or more of dietary prescription, supplement use, swallowing problem or BMI less than 24kg/m2 (sensitivity = 0.81, specificity = 0.50). 
Author Conclusion:

When compared with the nutritional risk rating at or above five, which indicates moderate or higher risk, the best set of indicator variables includes the variable representing a BMI below 24kg/m2, calculated from Section K height and weight, with the current trigger variables dietary prescription, supplement use and swallowing problem (sensitivity = 0.81, specificity = 0.50). These results suggest that the addition of BMI to Section K, as well as the use of BMI, supplement use and swallowing problems with the current trigger variables, would improve the MDS as a nutritional screening tool. The number of variables used as triggers could possibly be reduced to those shown to be significantly associated with nutritional risk. Because of the low prevalence of some trigger items in the sample population, this study lacks sufficient evidence to indicate precisely which trigger variables should be removed. In addition, other research has suggested that cognitive impairment is related to lower nutritional status; however, cognitive impairment is not included in Section K. To determine conclusively the usefulness of Section K as a nutritional risk screening tool, continued research and development are necessary.

Funding Source:
Not-for-profit
St. Joseph's Hospital Foundation and InterRAI
Other non-profit:
Reviewer Comments:

All residents were from one location.  Inclusion and exclusion criteria were not described. Authors note the limitation of the study design includes the introduction of criterion combination bias, secondary to the nature of the gold standard used for comparison.

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? Yes
  4.4. Were reasons for withdrawals similar across groups? ???
  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? Yes
  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? 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? 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? 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? N/A
  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? 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? Yes
  10.2. Was the study free from apparent conflict of interest? Yes