Determination of Protein Requirement in Elderly Male Subjects >75 Yrs Old

Minimal data are available on protein requirements throughout the lifespan. Currently available recommendations are based on nitrogen balance data. The limitations of the nitrogen balance method have been well described. Importantly, nitrogen balanced underestimates requirements.

The current dietary reference intake (DRI) requirement for healthy adult males is based on the reanalysis of the nitrogen balance date from Young and Scrimshaw. This data was reanalyzed statistically by Rand et al. and he concluded that the protein requirement of healthy adults was 0.65 and 0.83 (mean and RDA) g/kg/day of good quality protein. Using IAAO, our group estimated the protein requirement of young men (mean age 27 years) to be 0.93 and 1.2 g/kg/day (mean and RDA).

Currently there are no studies on protein requirement in the elderly. In a recent nutrition survey conducted by national health and nutrition examination survey (NHANES), the authors concluded that adults between the ages of 51 - 70 years old consumed an average on 1.0 g/kg/day (ideal body weight) of protein which represents about 15 % of calories. Depending on the calculations used for ideal body weight some older adults could be getting higher or lower than requirement. There is no scientifically derived protein estimate for older adults. Therefore there is a need to measurer protein requirement in that population.

The goal of this study therefore is to measure the protein requirement of male elderly subjects > 75 years using the indicator amino acid oxidation (IAAO) technique.

Hypothesis:

The investigators hypothesize the protein requirement in elderly male subjects will be lower (0.85-1.05 g/kg/day) than that established in young healthy males ( 0.93 - 1.2g/kg/day).

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Dietary supplement: Protein intake

• Study Type: Interventional
• Enrollment (Actual): 6
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5G 1X8
      • The Hospital for Sick Children

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 76 years to 90 years (OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

1. Healthy elderly males >75 years
2. Willingness to participate in the study
3. Males without a chronic disease or acute illness that could affect protein and amino acid (AA) metabolism eg, diabetes, cancer, liver or kidney disease, HIV, acute cold or flu, hypo or hyperthyroidism, rheumatoid arthritis treated with anti-inflammatory medications.
4. Males with hypertension if well controlled by medications

Exclusion Criteria:

1. Presence of disease known to affect protein and AA requirement and synthesis like diabetes, cancer, liver o kidney disease, HIV, acute cold or flu, hypo or hyperthyroidism, rheumatoid arthritis treated with anti-inflammatory medications.
2. On medications known to affect protein and amino acid metabolism like e.g. steroids.
3. Significant weight loss during the past month.
4. Individual on weight reducing diets.
5. Inability to tolerate the diet or unwilling to have blood drawn from a venous access for the purposes of the study.
6. Significant coffee consumption of more than 2 cups/day (400 mg of caffeine/day)
7. Significant Alcohol consumption of more than one drink/day ( 1 beer, ½ glass of wine)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: OTHER
• Allocation: NA
• Interventional Model: SINGLE_GROUP
• Masking: NONE

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: protein; varying protein intake in random order from deficient to excess	Dietary supplement: Protein intake; On the study day, the diet will be provided as free amino acids, with calories made up by a liquid diet and protein free cookies. Protein intakes will be varied as 0.2, 0.5, 0.7, 0.9, 1.0, 1.2, 1.5, 1.8, 2.0 g/kg/day.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Breath samples will be collected on day 3 of the experiment between the 4th and 5th meal and after the 6th and 7th meal. The ratios of carbon 13 to carbon 12 will be measured in breath.	10 months

Secondary Outcome Measures

Outcome Measure	Time Frame
Urine samples will be collected on day 3 of the experiment between the 4th and 5th meal and after the 6th and 7th meal for measurement of the rations of the enrichment of carbon 13 to carbon 12 in urine phenylalanine.	10 months

Collaborators and Investigators

• Sponsor: The Hospital for Sick Children
• Investigators: Principal Investigator: Paul B Pencharz, MD, PhD, The Hospital for Sick Children

Publications and helpful links

General Publications

• Rafii M, Chapman K, Elango R, Campbell WW, Ball RO, Pencharz PB, Courtney-Martin G. Dietary Protein Requirement of Men >65 Years Old Determined by the Indicator Amino Acid Oxidation Technique Is Higher than the Current Estimated Average Requirement. J Nutr. 2015 Apr 1;146(4):681-687. doi: 10.3945/jn.115.225631.

Study record dates

Study Major Dates

• Study Start: March 1, 2012
• Primary Completion (ACTUAL): June 1, 2014
• Study Completion (ACTUAL): June 1, 2014

Study Registration Dates

• First Submitted: August 16, 2013
• First Submitted That Met QC Criteria: September 18, 2013
• First Posted (ESTIMATE): September 23, 2013

Study Record Updates

• Last Update Posted (ACTUAL): January 9, 2018
• Last Update Submitted That Met QC Criteria: January 5, 2018
• Last Verified: January 1, 2018

More Information

Terms related to this study

• Other Study ID Numbers: 0019850580-D