UWL: Screening and Assessment Methods (2009)

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

To evaluate the nutritional status in a population of institutionalized elderly women, using the Mini Nutritional Assessment and other parameters known to be in relation with the nutritional status and its relationship with bone quality.

Inclusion Criteria:

Every woman aged more than 70 years who was living in one of the 11 selected nursing homes in Lausanne, Switzerland.

Exclusion Criteria:
  • Any specific treatment or drugs (hormonal replacement therapy, bisphosphonates, calcitonin, fluorides, corticosteroids or anti-convulsants)
  • Diseases affecting bone metabolism (primary hyperparathyroidism, osteomalacia or bone metastases)
  • Any severe disease affecting life expectancy. 
Description of Study Protocol:

Recruitment

11 nursing homes among 19 major institutions in Lausanne, Switzerland, which were already included in a prospective study assessing the effect of calcium and vitamin D on bone ultrasound.

Design

Cross-sectional study.

Statistical Analysis

  • For comparison between independent groups, when discontinuous data, Mann-Whitney U-tests were performed and when continuous data and impaired T-tests were used
  • To assess the relationship between MNA and anthropometric parameters, bone ultrasound and biochemical markers, a bivariate analysis using Spearman correlation coefficients was performed first
  • Multiple regression analysis was performed and specific T-scores were calculated.
Data Collection Summary:

Timing of Measurements

One-time measurements.

Dependent Variables

Bone quality assessed by quantitative bone ultrasound of the calcaneus (with an Achilles Lunar), which measured the Broadband Ultrasound Attenuation, Speed of Sound and the Stiffness Index.

Independent Variables

  • Nutritional status, as assessed by the Mini Nutritional Assessment
  • Tricipital skinfold was measured with a Penflural caliper 
  • Grip strength was measured with a Jamar hydraulic dynamometer
  • Functional status was evaluated by the Activities of Daily Living scale
  • Serum albumin level.
Description of Actual Data Sample:
  • Initial N: 78 institutionalized women
  • Attrition (final N): 78 women. Nine subjects had difficulties with the grip strength test and were excluded for that test.
  • Age: Aged 86±6 years
  • Ethnicity: Not mentioned.

Other Relevant Demographics

  • None of the women received estrogen replacement therapy, at least during the previous two years
  • Some women had taken calcium and vitamin D supplements up to two months before the beginning of the study.

Location

11 nursing homes in Lausanne, Switzerland.

Summary of Results:
Variables All Women (n=78) MNA Score greater than 24 (n=21) MNA Score 17 - 23.5 (n=45)

MNA Score less than 17 (n=12)

Age (Years)

86±6
85±7
86±6
89±6

BMI

25.6±5.6

27.8±3.6

26.1±6.0, P<0.01

20.0±2.6, P<0.01

Tricipital Skinfold (cm)
1.65±0.62
1.97±0.47
1.66±0.60, P<0.05 1.03±0.44, P<0.01
Grip Strength (kg)
11.4±5.2
12.2±5.1
11.2±5.1
10.5±6.3
ADL (Score)
3.47±1.68
4.36±1.22
3.57±1.51, P<0.01 1.58±1.62, P<0.01
Broadband Ultrasound Attenuation (dB/MHz)
92.5±9.1
94.8±10.8
92.1±8.6
89.8±7.1
Speed of Sound (m/s)
1,457±22
1,465±28
1,455±19
1,453±21
Stiffness (Percentage YA)
49.7±11.2
53.5±13.9
48.6±10.0
46.7±9.3
Serum Albumin (g/L)
43.2±5.1
45.7±4.8
42.7±4.3, P<0.05 39.6±5.9, P<0.01

Other Findings

  • Mean value of MNA was 21±4.1 (range, nine to 28)
  • 15% of the women were undernourished and 58% were at risk of malnutrition
  • As expected, compared with the well-nourished minority, undernourished subjects had significantly lower BMI, tricipital skinfold, ADL score and albumin level (all P<0.01)
  • The subjects at risk of malnutrition had significantly lower BMI (P<0.01), ADL score (P<0.01), tricipital skinfold (P<0.05) and serum albumin (P<0.05)
  • Ultrasound parameters were low independently of the nutritional status
  • MNA score correlated significantly with tricipital skinfold (R=0.508, P<0.01), ADL (R=0.538, P<0.01) and albumin serum level (R=0.409, P=0.01)
  • There was a trend for a correlation between the MNA and the ultrasound parameter Broadband Ultrasound Attenuation (R=0.207, P=0.07), whereas no correlation was found with Speed of Sound and Stiffness Index
  • A multivariate analysis showed that tricipital skin fold and ADL explained 61% of the variance of the MNA.
Author Conclusion:
  • In conclusion, malnutrition is frequent in institutionalized elderly persons in our country, with 15% of malnourished people and 58% at risk of malnutrition in this study and is usually underdiagnosed, like elsewhere
  • The nutritional status, assessed by the MNA, was correlated with the tricipital skin fold and with the ADL scale
  • There was only a trend for a correlation with bone health assessed by ultrasound because the latter was almost invariably low in this population, with malnutrition being only one of many pathogenic factors of osteoporosis.
Funding Source:
Other: Not reported
Reviewer Comments:

Subjects were part of a study assessing the effect of calcium and vitamin D on bone ultrasound. All were measurements not made in all subjects. Authors note the following limitations:

  • Relatively modest number of examined subjects
  • Advanced age of the population and osteoporosis in almost all subjects, preventing the correlations between MNA and bone ultrasound.
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? ???
  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)? 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? No
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