Unintended Weight Loss in Older Adults

UWL: Association With Outcomes (2009)

Citation:

Suzana S, Earland J, Suriah AR, Warnes AM. Social and health factors influencing poor nutritional status among rural elderly Malays. J Nutr Health Aging 2002;6(6):363-369.   

PubMed ID: 12459886
 
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 assess nutritional status and social and health factors influencing poor nutritional status among rural elderly Malays.

Inclusion Criteria:
  • Elderly Malays aged 60 years and older
  • Selected from 11 traditional villages in a rural area of Malaysia
  • Had resided in the selected villages for at least 12 months
  • Apparently healthy.
Exclusion Criteria:

Known terminal or mental illnesses.

Description of Study Protocol:

Recruitment

11 villages were randomly selected from the 62 villages in the district. Eligible respondents in the selected villages were invited to participate at their respective community centers.

Design

Cross-sectional study.

Statistical Analysis

  • Results presented according to age and according to two age groups: 60 to 74 years and 75 years and older
  • Independent sample two-tailed T test was used to examine differences between sexes and age groups for continuous data
  • Prior to analysis, skewed data were logarithmically transformed to meet the normality assumption of the test
  • Categorical data were analyzed using Pearson chi-squared test
  • Stepwise multiple least-squares regression analysis was used to determine social and health predictors of poor nutritional status as assessed by body mass index (BMI) and mid-upper arm circumference (MUAC)
  • Categorical variables were included as binary measures
  • Prior to the regression analysis, the distribution of the variables within the sample was examined
  • Variables that were reported by fewer than 5% of the sample, such as swallowing difficulty and unable to feed self, were excluded.
Data Collection Summary:

Timing of Measurements

One-time measurements. Study was done in 1995.

Dependent Variables

  • Nutritional status assessed using anthropometric measurements such as body weight, height, demispan, MUAC and skinfold thicknesses at triceps, biceps, subscapular and suprailiac
  • MUAC and corrected arm muscle area calculated from MUAC.

Independent Variables

  • Information on social and health aspects (demographic, socio-economic, psychological, physiological and physical health attributes) collected through questionnaire administered by six trained interviewers 
  • Age established through identity card, but some recorded ages may be inaccurate by five years more or less.
Description of Actual Data Sample:

Initial N: Of 498 eligible elderly people, 350 elderly Malays participated (70% response rate)

Attrition (final N): 350 elderly Malays (172 men, 178 women)

Age: Range, 60 years to 118 years

Ethnicity: Not mentioned

Other relevant demographics: Participants were comparable to the national population in demographic composition and in the prevalence of relevant physiological impairments

Location: Rural Malaysia.

 

Summary of Results:

Stepwise multiple regression of BMI and MUAC on social and health factors

Variables

BMI

B

BMI

SE

BMI

P value

MUAC

B

MUAC

SE

MUAC

P value

Unable to cook

-1.74 0.62 0.0054 -1.48 0.61 0.0150
Insufficient money -1.13 0.43 0.0087 -1.04 0.42 0.0135
Smoking -1.81 0.43 0.0001 -1.74 0.44 0.0001
Perceived weight loss -1.31 0.46 0.0510 -0.92 0.45 0.0432
Not married --- --- --- -1.39 0.44 0.0019
Loss of appetite --- --- ---  -0.84 0.42 0.0465
Depend on others for main economic resources --- --- --- -0.99 0.43 0.2140
Multiple R 0.38     0.40    

R2

0.14

 

 

0.16    

Other Findings

Weight, height, half-span, MUAC, mid-arm muscle circumference and corrected arm muscle area were all greater in men than in women (P<0.005 for all indices).

Conversely, all skinfold thicknesses were significantly higher in women than in men (P<0.005 for all indices).

In this sample, 38% of the subjects were underweight (BMI<18.5), particularly women. 

50% were within the optimal range for BMI (18.5 to 24.9).

Women were also found to be peripherally wasted, as assessed by MUAC (four times more likely, P<0.05), and by corrected arm muscle area (three times more likely, P<0.005).

It was found that 12% of subjects were overweight, the majority of whom were women; a significantly higher percentage of women (16.3%) than men (8.1%%) were overweight (P<0.05).

The predictors of BMI were: unable to cook, reported insufficient money to buy food, smokers and perceived weight loss.

The predictors of MUAC were: unable to cook, single, reported insufficient money to buy food, smokers, loss of appetite, depended on others for main economic resources, and perceived weight loss.

Author Conclusion:

In conclusion, although a subgroup of subjects was overweight (12%), a larger proportion of subjects were underweight (40%), indicating that chronic energy deficiency is a serious problem that needs urgent attention.  Prevention or early treatment of chronic energy deficiency is vital to restore immune function and competence and enhance the ability of elderly people to lead an independent life. It seems that the women and older elderly are at a greater risk of malnutrition. In addition, several social and health factors (such as "unable to cook", "reported insufficient money to buy food", "smokers", "perceived weight loss", "unmarried", "loss of appetite" and "depended on others for main economic resources") were associated with poor nutritional status in this population.

It is important that planners and others involved in working with this age group are aware of these risk factors when formulating future nutritional and health policies and planning intervention programs. However, it should be borne in mind that social and health factors influencing poor nutritional status may vary among geographical areas, ethnic groups and also would change over time. Therefore, it is essential to continuously identify the vulnerable group for effective nutrition intervention.

Funding Source:
University/Hospital: University Kebangsaan Malaysia
Not-for-profit
UK Nuffield Foundation
Other non-profit:
Reviewer Comments:

Nationally representative sample. Measurement of age may be inaccurate based on identity card. Authors note that skinfold thickness may not be a reliable indicator of body fat stores in elderly people. Questionnaire not tested for validity and reliability.

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? Yes
2. Was the selection of study subjects/patients free from bias? Yes
  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? Yes
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? N/A
  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? No
  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? 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? 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