Clinical determinants of resting metabolic rate in geriatric outpatients

Purpose: Accurate estimation of the energy requirements including resting metabolic rate (RMR) is important for optimal nutritional care, yet its clinical determinants are unknown. This study examined the associations between clinical determinants of the Comprehensive Geriatric Assessment (CGA) domains with RMR among geriatric outpatients. Materials & methods: Data were retrieved from cohorts of community-dwelling older adults (n = 84, 54 female) referring to geriatrics outpatient mobility clinics in both Amsterdam, The Netherlands and Melbourne, Australia. Determinants within domains of the CGA included diseases (number, type and severity of diseases, polypharmacy), nutrition (body weight, body mass index, absolute and relative skeletal muscle mass, fat-free mass and fat mass, risk of malnutrition), physical function (handgrip strength, Short Physical Performance Battery, Timed Up & Go), cognition (Mini-Mental State Examination), psychological wellbeing (Geriatric Depression Scale) and blood pressure. RMR was objectively measured using indirect calorimetry with a canopy hood. Association between the clinical determinants with standardized RMR (country and sex-specific z-score) were analysed with linear regression adjusted for age, sex and body weight. Results: Determinants within the nutritional domain were associated with RMR; body weight showed the strongest association with RMR. Significant associations between determinants within the nutritional domain with RMR disappeared after further adjustment for body weight. None of the other domains were associated with RMR. Conclusions: Body weight is the strongest clinical determinant of RMR and should be taken into account when estimating RMR in geriatric care

Sensory reweighting of proprioceptive input during balance control in healthy elderly

Sensory (re)weighting is the automated and unconscious process of combining sensory inputs, e.g. proprioception, graviception and vision, during human balance control. Typically reliable sensory inputs are weighted more than unreliable and noisy sensory inputs, to prevent deterioration of human balance control. Malfunctioning of sensory reweighting may be an important determinant of balance deficits in elderly with the consequence of falls. In this study we compared sensory (re)weighting of prioprioceptive input of the ankle joints, as one of the available sensory inputs, in healthy young versus healthy elderly during upright stance. Ten healthy young (aged 20-30 years) and ten healthy elderly (aged 75-80 years) were asked to maintain balance while proprioceptive input of each ankle was perturbed by rotations of the support surfaces around the ankle axes. Support surface rotations were applied with specific frequency content and increasing perturbation amplitude over trials. Body sway and reactive ankle torques were recorded. The sensitivity of the ankle torques to perturbation amplitude was determined using system identification techniques. The gain of a sensitivity function describes the ratio of perturbation amplitude and response amplitude as a function of frequency. Overall, elderly had a significant higher gain of the sensitivity function than young subjects. Increasing amplitude of the sensory perturbation resulted in a significant decrease of the gain of the sensitivity function from the perturbation amplitude to the ankle torque. Significant frequency-dependent interactions between group and perturbation amplitude could be established. A significant higher ankle torque sensitivity to perturbations indicates that elderly rely more strongly on proprioceptive input to maintain balance compared to younger subjects. Different reactions of elderly versus young subjects to perturbation amplitudes are indicative of differences in sensory reweighting. Results are important to understand interplay between available sensory inputs in balance and falling

Pulse transit time as a proxy for vasoconstriction in younger and older adults

Objectives: Changes of vasoconstriction may be measured non-invasively using pulse transit time. This study assessed the sensitivity, test-retest reliability and validity of pulse transit time during vasoconstriction provocation and active standing, and the predictive value of pulse transit time for blood pressure drop. Methods: Fifty-five younger (age 70 years) underwent electrocardiography, wrist and finger photoplethysmography and continuous blood pressure and total peripheral resistance measurements during vasoconstriction provocation using a cold pressor test (21 younger adults), or active stand tests (all other participants). Pulse transit tim

Pulse transit time as a proxy for vasoconstriction in younger and older adults

Objectives: Changes of vasoconstriction may be measured non-invasively using pulse transit time. This study assessed the sensitivity, test-retest reliability and validity of pulse transit time during vasoconstriction provocation and active standing, and the predictive value of pulse transit time for blood pressure drop. Methods: Fifty-five younger (age 70 years) underwent electrocardiography, wrist and finger photoplethysmography and continuous blood pressure and total peripheral resistance measurements during vasoconstriction provocation using a cold pressor test (21 younger adults), or active stand tests (all other participants). Pulse transit tim

Malnutrition is associated with dynamic physical performance

Background Malnutrition and poor physical performance are both conditions that increase in prevalence with age; however, their interrelation in a clinically relevant population has not been thoroughly studied. Aims This study aimed to determine the strength of the association between malnutrition and measures of both static and dynamic physical performance in a cohort of geriatric outpatients. Methods This cross-sectional study included 286 older adults (mean age 81.8, SD 7.2 years, and 40.6% male) who were referred to geriatric outpatient mobility clinics. The presence of malnutrition was determined using the Short Nutritional Assessment Questionnaire (SNAQ, cut-off ≥ 2 points). Measures of dynamic physical performance included timed up and go (TUG), 4-m walk test, and chair stand test (CST). Static performance encompassed balance tests and hand grip strength (HGS). Physical performance was standardized into sex-specific Z-scores. The association between malnutrition and each individual measure of physical performance was assessed using linear regression analysis. Results 19.9% of the cohort was identified as malnourished. Malnutrition was most strongly associated with CST and gait speed; less strong but significant associations were found between malnutrition and TUG. There was no significant association between malnutrition and HGS or balance. Discussion Physical performance was associated with malnutrition, specifically, dynamic rather than static measures. This may reflect muscle power being more impacted by nutritional status than muscle strength; however, this needs to be further addressed. Conclusions Malnutrition is associated with dynamic physical performance in geriatric outpatients, which should inform diagnosis and treatment/prevention strategies

Lack of Knowledge Contrasts the Willingness to Counteract Sarcopenia Among Community-Dwelling Adults

OBJECTIVE: Sarcopenia is highly prevalent in older adults. Knowledge among community-dwelling adults is important for effective prevention and treatment of sarcopenia. This study aims to assess current knowledge about sarcopenia, investigate willingness for treatment and prevention, and awareness of muscle health. METHOD: Participants who attended health educational events completed a questionnaire on knowledge about sarcopenia. Self-perceived muscle health was assessed by visual analog scale. Objective muscle measures included muscle mass, handgrip strength, and gait speed. RESULTS: Included participants were 197 (median aged 67.9 years [interquartile range = 57.0-75.1]). Eighteen participants (9%) reported to know what sarcopenia is. Participants' self-perceived muscle health showed a low correlation with all objective muscle measures. 76% were willing, in case of sarcopenia diagnosis, to start treatment and 71% were willing to prevent sarcopenia. DISCUSSION: Knowledge about sarcopenia is limited while participants were willing to start treatment and prevention. Strategies to increase knowledge among community-dwelling adults are needed

Gait speed assessed by a 4-m walk test is not representative of daily-life gait speed in community-dwelling adults

Objectives: Standardized tests of gait speed are regarded as being of clinical value, but they are typically performed under optimal conditions, and may not reflect daily-life gait behavior. The aim of this study was to compare 4-m gait speed to the distribution of daily-life gait speed. Study design: The cross-sectional Grey Power cohort included 254 community-dwelling participants aged 18 years or more. Main outcome measures: Pearson's correlations were used to compare gait speed assessed using a timed 4-m walk test at preferred pace, and daily-life gait speed obtained from tri-axial lower-back accelerometer data over seven consecutive days. Results: Participants (median age 66.7 years [IQR 59.4–72.5], 65.7% female) had a mean 4-m gait speed of 1.43 m/s (SD 0.21), and a mean 50th percentile of daily-life gait speed of 0.90 m/s (SD 0.23). Ninety-six percent had a bimodal distribution of daily-life gait speed, with a mean 1st peak of 0.61 m/s (SD 0.15) and 2nd peak of 1.26 m/s (SD 0.23). The percentile of the daily-life distribution that corresponded best with the individual 4-m gait speed had a median value of 91.2 (IQR 75.4–98.6). The 4-m gait speed was very weakly correlated to the 1st and 2nd peak (r = 0.005, p = 0.936 and r=0.181, p = 0.004), and the daily-life gait speed percentiles (range: 1st percentile r = 0.076, p = 0.230 to 99th percentile r = 0.399, p < 0.001; 50th percentile r = 0.132, p = 0.036). Conclusions: The 4-m gait speed is only weakly related to daily-life gait speed. Clinicians and researchers should consider that 4-m gait speed and daily-life gait speed represent two different constructs

A Sensor-Based Feedback Device Stimulating Daily Life Upper Extremity Activity in Stroke Patients:A Feasibility Study

This study aims to evaluate the feasibility and explore the efficacy of the Arm Activity Tracker (AAT). The AAT is a device based on wrist-worn accelerometers that provides visual and tactile feedback to stimulate daily life upper extremity (UE) activity in stroke patients. Methods: A randomised, crossover within-subject study was conducted in sub-acute stroke patients admitted to a rehabilitation centre. Feasibility encompassed (1) adherence: the dropout rate and the number of participants with insufficient AAT data collection; (2) acceptance: the technology acceptance model (range: 7–112) and (3) usability: the system usability scale (range: 0–100). A two-way ANOVA was used to estimate the difference between the baseline, intervention and control conditions for (1) paretic UE activity and (2) UE activity ratio. Results: Seventeen stroke patients were included. A 29% dropout rate was observed, and two participants had insufficient data collection. Participants who adhered to the study reported good acceptance (median (IQR): 94 (77–111)) and usability (median (IQR): 77.5 (75–78.5)-). We found small to medium effect sizes favouring the intervention condition for paretic UE activity (η2G = 0.07, p = 0.04) and ratio (η2G = 0.11, p = 0.22). Conclusion: Participants who adhered to the study showed good acceptance and usability of the AAT and increased paretic UE activity. Dropouts should be further evaluated, and a sufficiently powered trial should be performed to analyse efficacy.</p

Instrumented Assessment of Physical Activity Is Associated With Muscle Function but Not With Muscle Mass in a General Population

Objectives: Self-reported physical activity has shown to affect muscle-related parameters. As self-report is likely biased, this study aimed to assess the association between instrumented assessment of physical activity (I-PA) and muscle-related parameters in a general population. Method: Included were 156 young-to-middle-aged and 80 older community-dwelling adults. Seven days of trunk accelerometry (DynaPort MoveMonitor, McRoberts B.V.) quantified daily physical activity (i.e., active/inactive duration, number and mean duration of active/inactive periods, and number of steps per day). Muscle-related parameters included muscle mass, handgrip strength, and gait speed. Results: I-PA was associated with handgrip strength in young-to-middle-aged adults and with gait speed in older adults. I-PA was not associated with muscle mass in either age group. Discussion: The association between I-PA and muscle-related parameters was age dependent. The lack of an association between I-PA and muscle mass indicates the relevance of muscle function rather than muscle mass

Computed Tomography-Based Body Composition Is Not Consistently Associated with Outcome in Older Patients with Colorectal Cancer

Background: Current literature is inconsistent in the associations between computed tomography (CT)-based body composition measures and adverse outcomes in older patients with colorectal cancer (CRC). Moreover, the associations with consecutive treatment modalities have not been studied. This study compared the associations of CT-based body composition measures with surgery- and chemotherapy-related complications and survival in older patients with CRC. Materials and Methods: A retrospective single-center cohort study was conducted in patients with CRC aged ≥65 years who underwent elective surgery between 2010 and 2014. Gender-specific standardized scores of preoperative CT-based skeletal muscle (SM), muscle density, intermuscular adipose tissue (IMAT), visceral adipose tissue (VAT), subcutaneous adipose tissue, IMAT percentage, SM/VAT, and body mass index (BMI) were tested for their associations with severe postoperative complications, prolonged length of stay (LOS), readmission, and dose-limiting toxicity using logistic regression and 1-year and long-term survival (range 3.7–6.6 years) using Cox regression. Bonferroni correction was applied to account for multiple testing. Results: The study population consisted of 378 patients with CRC with a median age of 73.4 (interquartile range 69.5–78.4) years. Severe postoperative complications occurred in 13.0%, and 39.4% of patients died during follow-up. Dose-limiting toxicity occurred in 77.4% of patients receiving chemotherapy (n = 53). SM, muscle density, VAT, SM/VAT, and BMI were associated with surgery-related complications, and muscle density, IMAT, IMAT percentage, and SM/VAT were associated with long-term survival. After Bonferroni correction, no CT-based body composition measure was significantly associated with adverse outcomes. Higher BMI was associated with prolonged LOS. Conclusion: The associations between CT-based body composition measures and adverse outcomes of consecutive treatment modalities in older patients with CRC were not consistent or statistically significant. Implications for Practice: Computed tomography (CT)-based body composition, including muscle mass, muscle density, and intermuscular, visceral, and subcutaneous adipose tissue, showed inconsistent and nonsignificant associations with surgery-related complications, dose-limiting toxicity, and overall survival in older adults with colorectal cancer. This study underscores the need to verify whether CT-based body composition measures are worth implementing in clinical practice