Unintended Weight Loss in Older Adults

Healthy Non-Obese Adults (2010-2012)

Citation:

Lammes E, Akner G.  Resting metabolic rate in elderly nursing home patients with multiple diagnoses.  J Nutr Health Aging 2006;10(4):263-70.

PubMed ID: 16886096
 
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 measure RMR and nutrient induced thermogenesis in chronically diseased elderly living in a nursing home and test for a correlation with fat free mass, age, energy intake and activities of daily living.

Inclusion Criteria:

Residents had complex combinations of chronic diseases resulting in functional impairments with accompanying need of functional support and nursing care.

Exclusion Criteria:
  • Residents with severe dementia (n=2)
  • Died shortly after RMR had been measured, and no other examinations had been made, or their breathing was so irregular that no estimation of RMR could be made (n=7)
  • Ongoing infection (n=1)
  • Obviously not fasting (n=2)
  • Irregular breathing (n=1)
  • Unrealistic measured RMR (n=1)
Description of Study Protocol:

Recruitment

Subjects were elderly residents with multiple diagnoses living in a nursing home in Sundbyberg, a suburb of Stockholm, Sweden.

Design:  Cross-Sectional Study 

Blinding used (if applicable):  not applicable 

Intervention (if applicable):  not applicable 

Statistical Analysis

The univariate and multivariate analysis of explaining factors for RMR and nutrient induced thermogenesis was performed using a general linear model.  The regression was done stepwise backwards.  Fit was examined by standard residual plots.

Data Collection Summary:

Timing of Measurements

Measurements taken in resident's own apartments. 

Dependent Variables

  • RMR measured by indirect calorimetry and standard protocol 
  • Nutrient induced thermogenesis tested by giving the subjects a 200 ml, 200 kcal oral fluid test meal, then measuring metabolic rate again 1 hour later
  • Height, weight, BMI
  • Body composition measured anthropometrically through skinfold measurements and fat free mass calculated
  • Energy intake was calculated from 5 day food record of weighed food
  • BMR was calculated using 4 different prediction equations (Harris-Benedict, Schofield, WHO, 20 kcal/kg) and compared with measured RMR
  • Functional ability in Activities of Daily Living examined according to Katz index

Independent Variables

  • Elderly
  • Presence of chronic diseases

Control Variables

 

Description of Actual Data Sample:

Initial N: 81 individuals, 61 females, 20 males

Attrition (final N):  74 subjects for initial analysis.  RMR measurements were accepted for only 41/81 residents due to difficulties in performing measurements in elderly.

Age:  all females mean age:  85.6 +/- 6.8 years, all males mean age:  81.6 +/- 6.9 years

Ethnicity:  not mentioned

Other relevant demographics:

Anthropometrics:

Location:  Sweden

 

Summary of Results:

 

 

Females with reliable RMR (n=33)

All females (n=55)

Males with reliable RMR (n=8)

All males (n=14)

RMR (kcal/day)

1174 +/- 175 (810 - 1560) 1161 +/- 189 (810 - 1630) 1419 +/- 143 (1220 - 1570) 1474 +/- 173 (1220 - 1730)

RMR/body weight (kcal/kg/day)

20.4 +/- 4.3 (15.1 - 29.6)

20.7 +/- 4.3 (14.7 - 29.6)

20.7 +/- 3.1 (16.5 - 25.4)

20.9 +/- 3.1 (16.5 - 27.0)
RMR/fat free mass (kcal/kg FFM/day) 29.3 +/- 4.2 (22.0 - 39.2) 29.5 +/- 4.6 (20.4 - 40.5) 26.7 +/- 3.2 (22.2 - 31.6) 27.2 +/- 3.1 (22.2 - 32.6)
Energy intake (kcal/day) 1474 +/- 255 (1062 - 1939) 1476 +/- 223 (1037 - 1939) 1653 +/- 149 (1486 - 1895) 1764 +/- 228 (1486 - 2221)
Energy intake (kcal/kg body weight/day) 25.3 +/- 6.0 (16 - 39) 25.9 +/- 5.9 (16 - 40) 24.0 +/- 2.6 (20 - 28) 24.8 +/- 2.8 (20 - 30)
Energy intake (kcal/kg FFM/day) 36.5 +/- 6.2 (26 - 49) 37.2 +/- 6.4 (26 - 51) 31.1 +/- 2.5 (27 - 34) 32.4 +/- 3.0 (27 - 37)

Energy intake/RMR (estimate of PAL)

1.27 +/- 0.20 (0.97 - 1.72)

1.30 +/- 0.20 (0.97 - 1.76)

1.19 +/- 0.13 (1.00 - 1.35)

1.21 +/- 0.11 (1.00 - 1.35)

Other Findings

RMR was 1174 kcal/day (29.3 kcal/kg FFM/day).

Variation in RMR was significantly related to FFM (p < 0.0001).

Energy intake was 1474 kcal/day (36.5 kcal/kg FFM/day).

The energy intake/RMR ratio was 1.27 and nutrient induced thermogenesis was 15% (0 - 33%).

Nutrient induced thermogenesis was not related to any of parameters tested.

The equation of Harris & Benedict underestimated BMR by 4%, the WHO/FAO overestimated BMR by 7%; Schofield and an estimate of 20 kcal/kg/day did not significantly differ from the measured mean. 

Author Conclusion:

RMR was closely correlated to FFM.  Variations in nutrient induced thermogenesis could not be explained by any tested parameters.  Predicted BMR differed from measured RMR by less than 8% in all methods, but individual variations were large.

Funding Source:
University/Hospital: Karolinska Institute
Reviewer Comments:

Most measurements deemed unacceptable for inclusion in analysis.  Nutrient induced thermogenesis only measured for 1 hour following meal.  Authors note that the elevated RMR in those with a low FFM may be due to the normalization procedure.

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? Yes
  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? 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? ???
  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? Yes
  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? ???
  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