Measurement of Protein Intake and Physical Activity in Hospitalized Older Adults

Abstract

Background: Understanding and improving measurement of protein intake and measurement of physical activity is an important first step in being able to accurately test interventions in hospitalized older adults to optimize physical activity and recovery. Purpose: The aims of this dissertation were to: (1) describe measures of protein intake used with older adults across any setting of care; (2) test the reliability, validity and feasibility of PHOTOFOOD, an investigator developed tool and approach developed to measure protein intake in hospitalized adults; and (3) to compare two different estimation approaches when measuring intensity of physical activity with the MotionWatch 8. Methods: A systematic literature review was conducted to describe methods used to measure protein intake in studies conducted with older adults in all settings. A pilot study was conducted to evaluate the initial reliability and validity of PHOTOFOOD. A secondary data analysis was conducted using data obtained from participants in the intervention group from an acute care trial to compare Freedson and Landry’s cut-points for physical activity in hospitalized older adults. Results: The systematic review indicated that Food Frequency Questionnaires were the most common method used to measure protein intake. The PHOTOFOOD measure was subsequently developed to more accurately measure protein intake and a pilot study included evaluation of 12 meals. Participants consumed a mean of 19 grams of protein and there was evidence of inter-rater reliability based on 0.82 (P < 0.001) and validity based on a significant correlation between the PHOTOFOOD evaluation and direct tray visualization by the evaluator (r = 0.93, p<.01). The secondary data analysis supported the use of the of Landry cut points over Freedson cut points in that the Landry sedentary cut-point were significantly associated with function. Conclusions: There is support for the use of PHOTOFOOD and photo assisted dietary recall to obtain accurate protein intake in older adults and value in using the Landry cut points over Freedson when measuring physical activity intensity in older hospitalized adults. Future studies using PHOTOFOOD and direct measures of physical activity such as VO2 are needed to better measure these outcomes in hospitalized older adults.