Effects of oral amino acid supplementation on Multidimensional Prognostic Index in hospitalized older patients: a multicenter randomized, double-blind, placebo-controlled pilot study

Effects of essential amino acid (EAA) and glutamine supplementation on skeletal muscle wasting in acute, subacute, and postacute conditions

Under optimal physiological conditions, muscle mass maintenance is ensured by dietary protein, which balances the amino acid loss during the post-absorption period and preserves the body's protein homeostasis. Conversely, in critical clinical conditions (acute, subacute or postacute), particularly those related to hypomobility or immobility, combined with malnutrition, and local/systemic inflammation, the loss of muscle mass and strength can be quantitatively significant. A decline of more than 1% in muscle mass and of more than 3% in muscle strength has been registered in subjects with aged 20-37 yr after just five days of bed rest, similarly to those observed during one year of age-related decline in individuals over the age of 50. Loss of muscle mass and strength can have a dramatic effect on subjects' functional capacities, on their systemic metabolic control and on the amino acid reserve function, all of which are fundamental for the maintenance of other organs' and tissues' cell processes. References available indicate that the average 1%-2% reduction per day of muscle mass in patients in the intensive care unit (ICU) could represent an independent predictor of hospital mortality and physical disability in the five years following hospitalization. After just a few days or weeks of administration, supplementation with EAAs and glutamine has shown significant effects in maintaining muscle size and strength, which are typically negatively affected by some acute/subacute or postacute critical conditions (muscle recovery after surgery, oncology patients, ICU treatments), especially in the elderly or in those with pre-existing degenerative diseases. In this review, we focused on the theoretical bases and the most relevant clinical studies of EAA and glutamine supplementation as a single compound, with the aim of clarifying whether their combined use in a blend (EAAs-glutamine) could be potentially synergistic to prevent disease-related muscle wasting and its impact on the duration and quality of patients' clinical course.

An Amino Acid Mixture to Counteract Skeletal Muscle Atrophy: Impact on Mitochondrial Bioenergetics

Skeletal muscle atrophy (SMA) is caused by a rise in muscle breakdown and a decline in protein synthesis, with a consequent loss of mass and function. This study characterized the effect of an amino acid mixture (AA) in models of SMA, focusing on mitochondria. C57/Bl6 mice underwent immobilization of one hindlimb (I) or cardiotoxin-induced muscle injury (C) and were compared with controls (CTRL). Mice were then administered AA in drinking water for 10 days and compared to a placebo group. With respect to CTRL, I and C reduced running time and distance, along with grip strength; however, the reduction was prevented by AA. Tibialis anterior (TA) muscles were used for histology and mitochondria isolation. I and C resulted in TA atrophy, characterized by a reduction in both wet weight and TA/body weight ratio and smaller myofibers than those of CTRL. Interestingly, these alterations were lightly observed in mice treated with AA. The mitochondrial yield from the TA of I and C mice was lower than that of CTRL but not in AA-treated mice. AA also preserved mitochondrial bioenergetics in TA muscle from I and C mice. To conclude, this study demonstrates that AA prevents loss of muscle mass and function in SMA by protecting mitochondria.

Nutritional rehabilitation after acute illness among older patients: A systematic review and meta-analysis

BACKGROUND & AIMS

Acute illness can lead to disability and reduced quality of life in older patients. The aim of this systematic review was to evaluate the effect of nutritional rehabilitation provided during and after hospitalisation for an acute event on functional status, muscle mass, discharge destination and quality of life of older patients.

METHODS

The protocol for this systematic review was registered in PROSPERO (CRD42021264971). Articles were searched using Scopus, Medline, Google Scholar and Clinical.

TRIALS

gov. For studies included in the meta-analysis, Hedges'g standardized mean difference effect size was calculated and transformed in odds ratios.

RESULTS

We identified 7383 articles, of which 45 publications (41 trials, n = 8538 participants, mean age 80.35 ± 7.01 years.) were eligible for the systematic review. Patients were hospitalized for acute medical diseases (n = 6925) and fractures (n = 1063). The interventions included supplementation with a fixed amount of oral nutritional supplements (ONS, n = 17 trials), individualized diet plan (n = 3), combination of physical exercise with nutrition therapy (n = 14 trials), combination of anabolic agents with nutrition therapy (n = 5 trials). Overall nutritional rehabilitation improved functional status (Odds ratio 1.63 [1.15; 2.3], p = 0.003) and muscle mass (Odds ratio 2.61 [1.22; 5.5], p = 0.01), but not the quality of life or the discharge destination.

CONCLUSION

Nutritional rehabilitation was found to improve functional status and muscle mass. There is a need for larger studies involving older hospitalized patients.

Multidimensional frailty in older people in general practitioners’ clinical practice: the SELFY-MPI SIGOT project

The multidimensional prognostic index (MPI) is a comprehensive geriatric assessment (CGA) tool exploring the multiple domains of older subject. The knowledge and the diffusion of self-assessment tools for identifying frailty in general medicine is still limited. The aim of our study is to determine the prevalence of frailty using a multidimensional frailty screening tool (SELFY-MPI) in a cohort of older adults, belonging to the general practitioner’s (GPs) experience. In the frame of a national educational program organized by the Italian Geriatric Hospital and Community Society (SIGOT), expert geriatricians carried-out local courses addressed to GPs, focused on multidimensional approach in primary care. A cross-sectional study of the SELFY-MPI, based on eight different domains, in the general practitioners’ outpatient clinic was performed among 50 GPs. SELFY-MPI risk score was used for dividing the participants in robust, pre-frail, or frail. A total of 526 participants (mean age: 77.7 years; females=55.3%) fulfilled the SELFY-MPI. The participants were, on average, independent in the activities of daily living, had a good mobility, but they reported some cognitive difficulties, and they can be considered at risk of malnutrition. A high prevalence of comorbidities and polypharmacotherapy was also present. The 20.2% of the sample lived alone, suggesting a potential social frailty. The mean SELFY-MPI score was 0.26 0.17: therefore, 21.67% of the participants were categorized as pre-frail, and 3.99% as frail. Pre-frailty and frailty are common in GPs experience. SELFY-MPI is a feasible screening tool for multidimensional frailty in the GPs clinical practice.

Using the Multidimensional Prognostic Index (MPI) to improve cost-effectiveness of interventions in multimorbid frail older persons: results and final recommendations from the MPI_AGE European Project

MPI_AGE is a European Union co-funded research project aimed to use the Multidimensional Prognostic Index (MPI), a validated Comprehensive Geriatric Assessment (CGA)-based prognostic tool, to develop predictive rules that guide clinical and management decisions in older people in different European countries. A series of international studies performed in different settings have shown that the MPI is useful to predict mortality and risk of hospitalization in community-dwelling older subjects at population level. Furthermore, studies performed in older people who underwent a CGA before admission to a nursing home or receiving homecare services showed that the MPI successfully identified groups of persons who could benefit, in terms of reduced mortality, of specific therapies such as statins in diabetes mellitus and coronary artery disease, anticoagulants in atrial fibrillation and antidementia drugs in cognitive decline. A prospective trial carried out in nine hospitals in Europe and Australia demonstrated that the MPI was able to predict not only in-hospital and long-term mortality, but also institutionalization, re-hospitalization and receiving homecare services during the one-year follow-up after hospital discharge. The project also explored the association between MPI and mortality in hospitalized older patients in need of complex procedures such as transcatheter aortic valve implantation or enteral tube feeding. Evidence from these studies has prompted the MPI_AGE Investigators to formulate recommendations for healthcare providers, policy makers and the general population which may help to improve the cost-effectiveness of appropriate health care interventions for older patients.

An open-label, single-center pilot study to test the effects of an amino acid mixture in older patients admitted to internal medicine wards

OBJECTIVE

Older patients are frequently subjected to prolonged hospitalization and extended bed rest, with a negative effect on physical activity and caloric intake. This results in a consistent loss of muscle mass and function, which is associated with functional decline and high mortality. The aim of this study was to investigate the effect of 1 wk of oral amino acid (AA) supplementation in older patients subjected to low mobility during hospitalization.

METHODS

Hospitalized older patients (69-87) were included in the control group (n = 50) or were administered 25 g of AA mixture (n = 44) twice daily throughout 7 d of low mobility. We collected data related to length of stay as primary outcome measure. In-hospital mortality, 90-d postdischarge mortality, 90-d postdischarge rehospitalization, and falls also were considered. Moreover, variations of anthropometric measures, body composition and muscle architecture/strength, circulating interleukins, and oxidative stress markers between the beginning and the end of the supplementation period were analyzed as secondary outcomes.

RESULTS

Similar values were reported between the two groups regarding age (76.6 ± 6.8 versus 79 ± 7.2 y old), body weight (61.5 ± 14.3 versus 62.1 ± 16.1 kg), and body mass index (28.7 ± 4.15 versus 28.1 ± 3.62 kg/m²). Although no difference in terms of in-hospital, 90-d postdischarge, or overall mortality rate was observed between the two groups, a reduction in length of stay, 90-d postdischarge hospitalization, and falls was observed in the AA supplementation group rather than in controls. Furthermore, the AA mixture limited muscle architecture/strength impairment and circulating oxidative stress, which occurred during hospitalization-related bed rest. The latter data was associated with increased circulating levels of anti-inflammatory cytokines interleukin-4 and -10.

CONCLUSIONS

These results suggest that the AA mixture limits several alterations associated with low mobility in older hospitalized patients, such as length of stay, 90-d postdischarge hospitalization, and falls, preventing the loss of muscle function, as well as the increase of circulating interleukins and oxidative stress markers.

Vitamin D Deficiency and Sarcopenia in Older Persons

Vitamin D deficiency is a common health problem worldwide, in particular among older people. Vitamin D regulates and modulates the physiology and function of multiple human systems, including the skeletal muscle. The effect of vitamin D on the muscle has been widely investigated, suggesting that this hormone can stimulate the proliferation and differentiation of skeletal muscle fibers, maintaining and improving muscle strength and physical performance. Older persons have a higher prevalence of low Vitamin D levels as a consequence of low dietary intake and reduced ultraviolet irradiation of the skin. Therefore, older people with vitamin D deficiency might be at risk of sarcopenia, a geriatric syndrome characterized by the progressive loss of skeletal muscle mass and strength often complicated by adverse events, such as falls, disability hospitalization and death. Several randomized clinical trials have been conducted to investigate the effect of oral vitamin D supplementation in older patients to prevent or treat sarcopenia, but results are still controversial. In this narrative review we summarize the biological, clinical and epidemiological evidence supporting the hypothesis of a causal association between Vitamin D deficiency and an increased risk of sarcopenia in older people.

Older women are frailer, but less often die then men: a prospective study of older hospitalized people

OBJECTIVES

The association between frailty, mortality and sex is complex, but a limited literature is available on this topic, particularly for older hospitalized patients. Therefore, the objective of our study was to prospectively evaluate sex differences in frailty, assessed by the Multidimensional Prognostic Index (MPI) and mortality, institutionalization, and re-hospitalization in an international cohort of older people admitted to hospital.

STUDY DESIGN

We used data from nine public hospitals in Europe and Australia, to evaluate sex differences in mortality, frailty and the risk of institutionalization and re-hospitalization, during one year of follow-up.

MAIN OUTCOME MEASURES

People aged 65 years or more admitted to hospital for an acute medical condition or for a relapse of a chronic disease were included. A standardized comprehensive geriatric assessment, which evaluated functional, nutritional, and cognitive status, risk of pressure sores, comorbidities, medications and co-habitation status, was used to calculate the MPI to measure frailty in all hospitalized older people. Data regarding mortality, institutionalization and re-hospitalization were also recorded for one year.

RESULTS

Altogether, 1140 hospitalized patients (mean age = 84.2 years; 694 women = 60.9%) were included. The one-year mortality rate was 33.2%. In multivariate analysis, adjusted for age, MPI score, centre and diagnosis at baseline, although women had higher MPI scores than men, the latter had higher in-hospital (odds ratio, OR = 2.26; 95% confidence intervals, CI = 1.27-4.01) and one-year post-discharge mortality (OR = 2.04; 95%CI = 1.50-2.79). Furthermore, men were less frequently institutionalized in a care home than female patients (OR = 0.55; 95%CI: 0.34-0.91), but they were also more frequently re-hospitalized (OR = 1.42; 95%CI: 1.06-1.91) during the year after hospital discharge.

CONCLUSION

Older hospitalized men were less frail, but experienced higher in-hospital and one-year mortality than women. Women were admitted more frequently to nursing homes and experienced a lower risk of re-hospitalization. These findings suggest important differences between the sexes and extends the 'male-female health-survival paradox' to acutely ill patient groups.