Resting energy expenditure and carbohydrate oxidation are higher in elderly patients with COPD: a case control study

Combined Exercise Training and Nutritional Interventions or Pharmacological Treatments to Improve Exercise Capacity and Body Composition in Chronic Obstructive Pulmonary Disease: A Narrative Review

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease that is associated with significant morbidity, mortality, and healthcare costs. The burden of respiratory symptoms and airflow limitation can translate to reduced physical activity, in turn contributing to poor exercise capacity, muscle dysfunction, and body composition abnormalities. These extrapulmonary features of the disease are targeted during pulmonary rehabilitation, which provides patients with tailored therapies to improve the physical and emotional status. Patients with COPD can be divided into metabolic phenotypes, including cachectic, sarcopenic, normal weight, obese, and sarcopenic with hidden obesity. To date, there have been many studies performed investigating the individual effects of exercise training programs as well as nutritional and pharmacological treatments to improve exercise capacity and body composition in patients with COPD. However, little research is available investigating the combined effect of exercise training with nutritional or pharmacological treatments on these outcomes. Therefore, this review focuses on exploring the potential additional beneficial effects of combinations of exercise training and nutritional or pharmacological treatments to target exercise capacity and body composition in patients with COPD with different metabolic phenotypes.

Impairment and characteristics of postural control sub-components in people with COPD: a scoping review

Purpose: Impairment of postural control is common in people with COPD. However, the precise characteristics of this alteration are not clearly known. The "Systems Framework for Postural Control" which define postural control sub-components, represents an interesting tool to explore this field. The main aim of this review was to identify which postural control sub-components are impaired in people with COPD and to summarise characteristics for each sub-component. A secondary aim was to precise the relation between postural control and activities of daily living (ADL).Materials and methods: A scoping review was conducted, according to the JBI methodology. Medline, Cochrane Library, Scielo, Google Scholar, OpenGrey, and HAL were searched from inception to May 2022. The search was performed in English and French.Results: Eighty-nine articles were included. There was evidence of a potential impairment for most of the postural control sub-components. Characteristics of every sub-component alteration were heterogeneous. Reduced postural control could be associated with difficulties in ADL.Conclusions: People with COPD may have impairment in a wide range of postural control sub-components. Further research is needed to clarify if a common pattern of modification exits for this alteration and to precise the link with ADL.Implications for rehabilitationImpairment of postural control is a common extra-respiratory manifestation in people with COPD and so clinicians must include it in their clinical reasoning.Numerous postural control sub-components could be altered in people with COPD, suggesting that postural control assessment must be holistic.This scoping review shows that characteristics of postural control impairment are varied and that there may be no common pattern at the COPD population level.The relationship between impaired postural control and activities of daily living remains unclear, but clinicians should be alert to potential negative interactions between these two areas.

Energy Intake of Men With Excess Weight During Normobaric Hypoxic Confinement

Due to the observations of weight loss at high altitude, normobaric hypoxia has been considered as a method of weight loss in obese individuals. With this regard, the aim of the present study was to determine the effect of hypoxia per se on metabolism in men with excess weight. Eight men living with excess weight (125.0 ± 17.7 kg; 30.5 ± 11.1 years, BMI: 37.6 ± 6.2 kg⋅m-2) participated in a randomized cross-over study comprising two 10-day confinements: normobaric (altitude of facility ≃ 940 m) normoxia (NORMOXIA; P I O2 = 133 mmHg), and normobaric hypoxia (HYPOXIA). The P I O2 in the latter was reduced from 105 (simulated altitude of 2,800 m) to 98 mmHg (simulated altitude of 3,400 m over 10 days. Before, and at the end of each confinement, participants completed a meal tolerance test (MTT). Resting energy expenditure (REE), circulating glucose, GLP-1, insulin, catecholamines, ghrelin, peptide-YY (PYY), leptin, gastro-intestinal blood flow, and appetite sensations were measured in fasted and postprandial states. Fasting REE increased after HYPOXIA (+358.0 ± 49.3 kcal⋅day-1, p = 0.03), but not after NORMOXIA (-33.1 ± 17.6 kcal⋅day-1). Postprandial REE was also significantly increased after HYPOXIA (p ≤ 0.05), as was the level of PYY. Furthermore, a tendency for decreased energy intake was concomitant with a significant body weight reduction after HYPOXIA (-0.7 ± 0.2 kg) compared to NORMOXIA (+1.0 ± 0.2 kg). The HYPOXIA trial increased the metabolic requirements, with a tendency toward decreased energy intake concomitant with increased PYY levels supporting the notion of a hypoxia-induced appetite inhibition, that could potentially lead to body weight reduction. The greater postprandial blood-glucose response following hypoxic confinement, suggests the potential development of insulin resistance.

Indirect Calorimetry as an Instrument of Research to Identify the Effect of Hypermetabolism in Critical Patients' Prognosis

Background: Energy expenditure (EE) evaluation in Intensive Care Unit (ICU) patients can be very challenging. Critical illness is characterized by great variability in EE, which is influenced by the disease itself and the effects of treatment. Indirect calorimetry (IC) is currently the gold standard to measure EE in Intensive Care Unit (ICU) patients. However, calorimeters are not widely available, and predictive formulas (PF) are still commonly used, leading to under or overfeeding and deleterious consequences.Important metabolic changes occur and catabolism becomes prominent in critically ill patients.Both hyper and hypometabolism can be observed, but hypermetabolic patients appear to have higher mortality rates compared to metabolically normal patients. This study aimed to assess hypermetabolism incidence and compare clinical outcomes between hypermetabolic and normometabolic patients in ICU.

Methods: A single-center, retrospective, and observational study was conducted in the ICU of the Hospital do Divino Espírito Santo in Ponta Delgada, between August 2018 and February 2021. Only invasively mechanically ventilated patients were included. Resting energy expenditure (REE) was predicted by 25 kcal/kg/day formula to obtain predicted resting energy expenditure (PREE), and REE was measured by IC to obtain measured resting energy expenditure (MREE). According to their metabolic state (PREE/MREE), patients were divided into hypermetabolic (≥1.3) and normometabolic (<1.3). To determine the limits of agreement between PREE and MREE, we performed a Bland-Altman (BA) analysis. Baseline characteristics, severity criteria, nutritional status, and main diagnosis on admission were compared. The primary outcome considered was 30-day mortality. Other outcomes such as the ICU length of stay (LOS), in-hospital LOS, and length of invasive ventilation were also evaluated.

Results: Among the 80 ICU patients included in the final analysis, 67 patients were normometabolic (83.4%). Patients admitted due to pneumonia were more hypermetabolic, 8 (61.5%) vs. 10 (14.9%); p<0.001. Hypermetabolism was found also in patients admitted due to sepsis/septic shock, 7 (53.8%) vs. 16 (23.9%); p=0.029. Hypermetabolic patients had lower body mass index (22.5 [interquartile range (IQR): 21.5-24.9] vs. 27.7 [IQR: 25.0-32.4] kg/m²; p=0.001) and higher MREE (2715.0 [2399.0-3090.0] vs. 1690.0 [1410.0-2190.0] kcal/day; p<0.001). Bland-Altman analysis showed a mean difference of -5.6 ± 744.7 Kcal/day between the PREE and MREE by IC. No statistically significant difference was found between the two groups, neither in 30-day mortality nor in the other outcomes considered.

Conclusions: Hypermetabolism was not seen to present a greater risk of death in mechanically ventilated patients in ICU. Lower BMI, sepsis/septic shock, and pneumonia appear to be associated with a hypermetabolic state.

Association of resting energy expenditure and nutritional substrate oxidation with COPD stage and prediction indexes

While increase in resting energy expenditure (REE) of COPD patients is generally accepted, there is a lack of information about nutritional substrates oxidation (NSO) in this specific population. The aim of this study was comparison of REE and NSO from indirect calorimetry between COPD patients and control subjects and to evaluate possible associations with the disease stage and prediction indexes. In this observational study, 50 consecutive outpatients with stable COPD (COPD group) were examined and compared with 25 volunteers without respiratory problems (control group). Body composition, REE and NSO were determined in all study participants. All COPD subjects underwent a comprehensive examination to determine COPD severity and prognostic scales. Measured REE values adjusted for body weight, fat-free mass (FFM), and body surface were approximately 10% higher in COPD patients than in the control group. Respiratory quotient (RQ) and non-protein RQ (nRQ) values were respectively 5% and 10% higher in the COPD group. Adjusted carbohydrate oxidation was almost two times higher in comparison with the control group. We found no differences in absolute values of lipid and protein oxidation between the groups. Correlation analysis proved a positive association of relatively expressed REE and oxidation of lipids, and a negative association of RQ, nRQ and oxidation of carbohydrates with the value of prediction indexes. In conclusion, our study demonstrated metabolic changes in COPD patients leading to increased values of REE and changes in NSO which were associated with the disease stage, and which can be applied for nutritional support in clinical practice.

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.

New equation to estimate resting energy expenditure in non-critically ill patients

BACKGROUND

Correct measurement of resting energy expenditure (REE) is essential to offer a proper nutritional management during hospital stay. Dietitians are not able to perform an effective dietary treatment if predicted REE values are obtained from invalid equations.

OBJECTIVE

The aim of this study was to develop a more valid method to estimate REE in non-critically ill Portuguese patients.

DESIGN

In this cross-sectional study, REE was measured by indirect calorimetry (IC) in 180 non-critically patients during hospital stay (50 participants were allocated to the validation group by simple randomization and the remaining 130 were allocated to the derivation group). The best accurate equations were derived by multiple linear regression analysis (stepwise) based on anthropometric variables. The equations were tested on the validation group and compared with published predictive equations.

RESULTS

Data was collected from 130 patients, 68 women (52.3%) and 62 men (47.7%), mean age was 58.9 ± 16.8 years and REE-IC was 1918 ± 721 kcal/day. The new best-fit equation REE (kcal/day) = 14.4 (Height) + 52.7 (MUAC) + 453.4 (1 if male, 0 if female) - 371.2 (if Obese) - 2138.3 showed strength of evidence decisive (BF₁₀ = 8008), when compared by Bayesian model, and r² = 0.315. Only estimated REE values obtained using new equations did not present significant difference when compared with measured REE values (kcal/kg).

CONCLUSIONS

In this study, new equations derived from a non-critically ill population showed higher validity in estimating REE than currently used equations. A better estimation of REE may lead to a better nutritional intervention and a decreased risk of undernutrition in hospitalized patients.

Nutritional status and functionality in geriatric rehabilitation patients: a systematic review and meta-analysis

PURPOSE

Since there is only limited evidence available for geriatric rehabilitation patients, this systematic review and meta-analysis aims to characterize the nutritional status in this population and its relationship with functionality.

METHODS

Eight databases were searched for full-text articles reporting baseline nutritional intake and status of adults ≥ 60 years in rehabilitation settings. Pooled estimates were calculated for prevalence of malnutrition and risk of malnutrition based on the Mini Nutritional Assessment (MNA) and for mean body mass index (BMI). Associations between nutritional status (MNA, MNA short form and BMI) and functional status (Barthel Index and Functional Independence Measure) and prevalence of sarcopenia were reviewed.

RESULTS

62 out of 1717 references were eligible for inclusion. Pooled prevalence [95% confidence interval (CI)] of malnutrition and risk of malnutrition were 13 (5-20) % and 47 (40-54) %. Pooled estimate (95% CI) for BMI was 23.8 (23.2-24.5) kg/m². Existing data suggest a risk for low protein and energy intake and vitamin D deficiency. Functional status differed widely. Seven out of ten studies reported significant associations between reduced nutritional status and reduced functionality, whilst two out of seven studies reported significant associations between higher BMI and functionality. Prevalence of sarcopenia was high with 40-76% in this population.

CONCLUSIONS

Although geriatric rehabilitation populations and settings were heterogeneous, a relevant percentage of geriatric rehabilitation patients were affected by a reduced nutritional status. Nutritional status was associated with decreased functionality. This emphasizes the need for screening for malnutrition and targeted nutritional intervention.

Effect of Hypercapnia, an Element of Obstructive Respiratory Disorder, on Pancreatic Cancer Chemoresistance and Progression

BACKGROUND

Chronic obstructive respiratory disorders (ORDs) are linked to increased rates of cancer-related deaths. Little is known about the effects of hypercapnia (elevated CO₂) on development of pancreatic ductal adenocarcinoma (PDAC) and drug resistance.

STUDY DESIGN

Two PDAC cell lines were exposed to normocapnic (5% CO₂) and hypercapnic (continuous/intermittent 10% CO₂) conditions, physiologically similar to patients with active ORD. Cells were assessed for proliferation rate, colony formation, and chemo-/radiotherapeutic efficacy. In a retrospective clinical study design, patients with PDAC who had undergone pancreatic resection between 2002 and 2014 were reviewed. Active smokers were excluded to remove possible smoking-related protumorigenic influence. Clinical data, pathologic findings, and survival end points were recorded. Kaplan-Meier and Cox regression analyses were performed.

RESULTS

Exposure to hypercapnia resulted in increased colony formation and proliferation rates in vitro in both cell lines (MIA-PaCa-2: 111% increase and Panc-1: 114% increase; p < 0.05). Hypercapnia exposure induced a 2.5-fold increase in oxaliplatin resistance (p < 0.05) in both cell lines and increased resistance to ionizing radiation in MIA-PaCa-2 cells (p < 0.05). Five hundred and seventy-eight patients were included (52% were male, median age was 68.7 years [interquartile range 60.6 to 76.8 years]). Cox regression analysis, assessing TNM staging, age, sex, and ORD status, identified ORD as an independent risk factor for both overall survival (hazard ratio 1.64; 95% CI, 1.2 to 2.3; p < 0.05) and disease-free survival (hazard ratio 1.68; 95% CI, 1.06 to 2.67).

CONCLUSIONS

PDAC cells exposed to hypercapnic environments, which is common in patients with ORD, showed tumor proliferation, radioresistance, and chemoresistance. Patients with a history of ORD had a worse overall prognosis, suggesting that hypercapnic conditions play a role in the development and progression of PDAC and stressing the need for patient-tailored care.

Energy efficient physiologic coupling of gait and respiration is altered in chronic obstructive pulmonary disease

AIMS

Coupling between walking and breathing in humans is well established. In healthy systems, the ability to couple and uncouple leads to energy economization. It is unknown if physiologic efficiency is susceptible to alteration, particularly in individuals with airflow obstruction. The aim of this research was to determine if coupling was compromised in a disease characterized by abnormal airflow and dyspnoea, and if this was associated with reduced energy efficiency.

METHODS

As a model of airflow obstruction, 17 chronic obstructive pulmonary disease (COPD) patients and 23 control subjects were included and walked on a treadmill for 6 minutes at three speeds (preferred speed and ±20% preferred speed) while energy expenditure, breathing, and walking were recorded. Rating of perceived exertion was recorded at the end of each walking trial. The most commonly used frequency ratio (ie, strides:breath) and cross recurrence quantification analysis were used to quantify coupling. Linear regression models were used to determine associations.

RESULTS

Less complex frequency ratios, simpler ratios, (ie, 1:1 and 3:2) accompanied with stronger coupling were moderately associated with increased energy expenditure in COPD subjects. This was found for all three speeds.

CONCLUSION

The novel finding was that increased energy expenditure was associated with stronger and less complex coupling. Increased effort is needed when utilizing a frequency ratio of 1:1 or 3:2. The more stable the coupling, the more effort it takes to walk. In contrast to the complex energy efficient coupling of controls, those with airflow obstruction manifested simpler and stronger coupling associated with reduced energy efficiency.

Estimating Resting Energy Expenditure by Different Methods as Compared With Indirect Calorimetry for Patients With Pulmonary Hypertension

BACKGROUND

For patients with pulmonary hypertension, nutrition status is an independent predictor of morbidity and mortality, and energy expenditure can be strongly influenced by lung disease. Indirect calorimetry (IC) is the gold standard for measuring resting energy expenditure (REE), this study aimed to compare the results of REE estimated by different methods with those obtained by IC for patients with pulmonary hypertension.

METHODS

In this cross-sectional study (n = 34), REE was estimated by bioelectrical impedance analysis and the predictive equations of Harris-Benedict, Food and Agriculture Organization / World Health Organization, Institute of Medicine, Cunningham, Katch-McArdle, and Mifflin-St Jeor.

RESULTS

Mean patient age was 47.0 ± 14.5 years, and 76.5% were women. REE obtained with IC was strongly correlated with all other estimation methods but showed higher mean values: IC 1750.8 ± 434.3 kcal vs bioelectrical impedance analysis, 1549.0 ± 417.8 kcal; Harris-Benedict, 1493.1 ± 337.0 kcal; FAO/WHO, 1536.1 ± 345.0 kcal; Institute of Medicine, 1457.1 ± 293.2 kcal; Cunningham, 1597.3 ± 292.3 kcal; Katch-McArdle, 1447.7 ± 287.0 kcal; and Mifflin-St Jeor, 1388.7 ± 303.9 kcal. The analysis of agreement showed a clinically significant bias of approximately -255 kcal in all estimation methods when compared with IC.

CONCLUSION

Although there was a strong correlation between REE estimation methods and IC, there was no agreement between them. All estimation methods underestimated energy needs by about 255 kcal for patients with pulmonary hypertension, and the Cunningham equation had the smallest difference in relation to IC.

Indirect calorimetry in nutritional therapy. A position paper by the ICALIC study group

BACKGROUND & AIMS

This review aims to clarify the use of indirect calorimetry (IC) in nutritional therapy for critically ill and other patient populations. It features a comprehensive overview of the technical concepts, the practical application and current developments of IC.

METHODS

Pubmed-referenced publications were analyzed to generate an overview about the basic knowledge of IC, to describe advantages and disadvantages of the current technology, to clarify technical issues and provide pragmatic solutions for clinical practice and metabolic research. The International Multicentric Study Group for Indirect Calorimetry (ICALIC) has generated this position paper.

RESULTS

IC can be performed in in- and out-patients, including those in the intensive care unit, to measure energy expenditure (EE). Optimal nutritional therapy, defined as energy prescription based on measured EE by IC has been associated with better clinical outcome. Equations based on simple anthropometric measurements to predict EE are inaccurate when applied to individual patients. An ongoing international academic initiative to develop a new indirect calorimeter aims at providing innovative and affordable technical solutions for many of the current limitations of IC.

CONCLUSION

Indirect calorimetry is a tool of paramount importance, necessary to optimize the nutrition therapy of patients with various pathologies and conditions. Recent technical developments allow broader use of IC for in- and out-patients.

Nutritional Intake, Energy Expenditure, and Growth of Infants Following Congenital Diaphragmatic Hernia Repair

BACKGROUND/OBJECTIVES

The pathophysiology of failure to thrive in congenital diaphragmatic hernia (CDH) has not been fully elucidated, and the nutritional care of these infants is hindered by paucity of data on the optimal calorie requirements for growth. The primary objective of this study was to investigate the energy intake required for infants with CDH to grow optimally at the time of first hospital discharge. The secondary objectives were to assess their measured resting energy expenditure in infancy, and their long-term growth outcomes.

METHODS

Nutritional intake, anthropometrics, indirect calorimetry results, and respiratory status of infants with CDH from 2011 to 2014 were collected retrospectively. Data on confounders (gastroesophageal reflux disease and feeding intolerance, respiratory rate and pulmonary hypertension) were also collected. Analyses were performed using Stata (College Station, TX).

RESULTS

Of the 72 infants diagnosed with CDH during that period of time, 43 met the inclusion criteria. A caloric intake of 125.0 ± 20 kcal · kg · day was required to meet discharge weight gain criteria (25-35 g · kg · day). In a subset of 17 patients, measured resting energy expenditure was higher than predicted resting energy expenditure (58.0 ± 18 vs 46.6 ± 3 kcal · kg · day, P < 0.05), and 59% of infants were hypermetabolic (measured resting energy expenditure >110% of predicted resting energy expenditure) in early infancy. Failure to thrive prevalence at discharge was 16.2% compared to 3.6% and 4.2% at 12- and 24-months of age, respectively (P = 0.03; P = 0.005, respectively).

CONCLUSIONS

Optimal weight gain can be achieved with higher than predicted calorie provision. Most infants with CDH are hypermetabolic. Despite this, failure to thrive prevalence can improve during the first year of life.