UWL: Screening and Assessment Methods (2009)

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

To examine whether the Mini-Nutritional Assessment (MNA) and MNA-SF can screen and diagnose for malnutrition and risk for malnutrition in the Japanese elderly population.

Inclusion Criteria:

Elderly men and women from geriatric outpatient clinics, nursing homes, geriatric hospitals and home care patients.

Exclusion Criteria:

Subjects diagnosed with infection, inflammation, liver disorders, kidney disorders, cancer or bone marrow proliferative disorders were excluded by physicians.

Description of Study Protocol:

Recruitment

68 consecutive outpatients were living at home independently or with mild decline in activities of daily living. 53 residents and 72 inpatients with mild to severe dependency in activities of daily living were randomly chosen from one private nursing home and two geriatric hospitals, respectively. 33 patients living at home and receiving home care services were also eligible.

Design

Cross-Sectional Study 

Statistical Analysis

  • Differences between groups were determined by ANOVA or the Kruskal-Wallis test, depending on the distribution of the analyzed variable
  • Partial rank correlation coefficients adjusted for age were used to measure the relations between MNA total score, MNA-SF, anthropometric measurements and biochemical markers
  • To identify optimal threshold values for predicting malnutrition, receiver operating characteristic curve analysis was performed by computing the sensitivity and specificity of the different tests at various cutoff levels
  • The best Youden index was used to determine the best cutoff point
  • The Kolmogorov-Smirnov test was used to check the normal distribution of variables.
Data Collection Summary:

Timing of Measurements

Measurements made at the same time

Dependent Variables

Nutritional status

Independent Variables

  • Mini-Nutritional Assessment: Used to assess nutritional status, includes 18 items, including anthropometric measurements (BMI, mid-arm circumference, calf circumference, weight loss, a global assessment [six questions related to lifestyle, medication and mobility], a dietary questionnaire [eight questions related to number of meals, food and fluid intake] and a subjective assessment (self-perception of health and nutrition)   
  • MNA-SF: Comprises six of the 18 items
  • Anthropometric measurements: BMI, triceps skinfold, mid-arm and calf circumferences 
  • Fasting blood samples analyzed for serum albumin, total cholesterol and total lymphocyte counts. 

Control Variables

Age

Description of Actual Data Sample:

Sample: 226 elderly Japanese patients, 67 men, 159 women

Age: Mean 77.8±13.8 years 

Location: Japan

Summary of Results:

Correlation Between MNA Total or MNA-SF Score and Nutritional Parameters in Japanese Elderly

Variables Correlation with MNA
Total Score
Correlation with MND-SF Score

Age (n=234)

r= -0.14, P=0.036 r= -0.16, P=0.012

BMI (n=233)

r=0.59, P<0.0001

r=0.57, P<0.0001

Mid-arm Circumference (n=227) r=0.50, P<0.0001 r=0.33, P<0.0001
Triceps Skinfold (n=225) r=0.37, P<0.0001 r=0.24, P=0.003
Calf Circumference (n=225) r=0.28, P<0.0001 r=0.31, P<0.0001
Albumin (n=179) r=0.60, P<0.0001 r=0.56, P<0.0001
Total Cholesterol (n=177) r=0.36, P<0.0001 r=0.30, P<0.0001
Lymphocyte (n=161) r=0.01, P<0.930 r=0.04, P=0.96
MNA Total Score (n=226) --- r=0.88, P<0.0001

Other Findings

  • MNA total scores averaged 20.2±4.6 and ranged from a minimum of 4.0 to a maximum of 27.5, with a median of 21.0
  • According to the original cutoff point of the full MNA, 19.9% of those assessed were malnourished (score below 17)
  • 58.0% were at risk of malnutrition (score between 17 and 23.5), and 22.1% were well nourished (score at least 24)
  • Significant correlations were found between full MNA scores and age (r= -0.14), BMI (r=0.59), serum albumin (r=0.60), total cholesterol (r=0.36), mid-arm circumference (r=0.50), and triceps skinfold (r=0.37)
  • The area under the curves, which represent the overall accuracy of the MNA total score as a test for malnutrition, was found to be 0.916 for albumin (P<0.0001), 0.912 for total cholesterol (P<0.0001) and 0.855 for BMI (P<0.0001), indicating that the MNA test is relatively accurate
  • The sensitivity and specificity of the full MNA score (less than 17) for hypoalbuminemia were 0.810 and 0.860, respectively
  • With a cutoff point lower than 18, sensitivity and specificity for hypoalbuminemia were 0.857 and 0.815, respectively
  • Using a short-form MNA score 12 and higher as normal, its sensitivity and specificity for predicting undernutrition were 0.859 and 0.840, respectively. 
Author Conclusion:

In the present study, the MNA was validated in the Japanese elderly. The full and short forms of the MNA were useful tools to identify elderly Japanese patients with malnutrition or risk of malnutrition. However, the full MNA cutoff point for malnutrition should be modulated for this population (shift to a higher point, namely below 18).

Funding Source:
Government: Comprehensive Research on Aging and Health from the Ministry of Health and Welfare of Japan
Reviewer Comments:

Measurements not made in all subjects. Authors note that the study group did not include elderly subjects with comorbid conditions, therefore, this sample is not considered representative of the elderly Japanese population, and results may apply only to Japanese elderly in ill health.

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? Yes
  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? 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%.) Yes
  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? 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? ???
  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? ???
  7.6. Were other factors accounted for (measured) that could affect outcomes? ???
  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)? 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