Estimation of lean body weight in older women with hip fracture

Frailty and sarcopenia: From theory to clinical implementation and public health relevance

The sustainability of healthcare systems is threatened by the increasing (absolute and relative) number of older persons referring to clinical services. Such global phenomenon is questioning the traditional paradigms of medicine, pushing towards the need of new criteria at the basis of clinical decision algorithms. In this context, frailty has been advocated as a geriatric condition potentially capable of overcoming the weakness of chronological age in the identification of individuals requiring adapted care due to their increased vulnerability to stressors. Interestingly, frailty poses itself beyond the concept of nosological conditions due to the difficulties at correctly framing traditional diseases in the complex and heterogeneous scenario of elders. Thus, frailty may play a key role in public health policies for promoting integrated care towards biologically aged individuals, currently presenting multiple unmet clinical needs. At the same time, the term frailty has also been frequently used in the literature for framing a physical condition of risk for (mainly functional) negative endpoints. The combination of such physical impairment with an organ-specific phenotype (e.g., the age-related skeletal muscle decline or sarcopenia) may determine the assumptions for the development of a clinical condition to be used as potential target for ad hoc interventions against physical disability. In the present article, we present the background of frailty and sarcopenia, and discuss their potentialities for reshaping current clinical and research practice in order to promote holistic approach to older patients, solicit personalization of care, and develop new targets for innovative interventions.

DESIGNING DRUG TRIALS FOR SARCOPENIA IN OLDER ADULTS WITH HIP FRACTURE - A TASK FORCE FROM THE INTERNATIONAL CONFERENCE ONFRAILTY AND SARCOPENIA RESEARCH (ICFSR)

In May 2012, a Sarcopenia Consensus Summit was convened by the Foundation of the National Institutes of Health (FNIH), National Institute of Aging (NIA), and the U.S. Food and Drug Administration (FDA); and co-sponsored by five pharmaceutical companies. At this summit, sarcopenia experts from around the world worked to develop agreement on a working definition of sarcopenia, building on the work of previous efforts to generate a consensus. With the ultimate goal of improving function and independence in individuals with sarcopenia, the Task Force focused its attention on people at greatly increased risk of muscle atrophy as a consequence of hip fracture. The rationale for looking at this population is that since hip fracture is a recognized condition, there is a clear regulatory path forward for developing interventions. Moreover, patients with hip fracture may provide an appropriate population to advance understanding of sarcopenia, for example helping to define diagnostic criteria, develop biomarkers, understand the mechanisms that underlie the age-related loss of muscle mass and strength, and identify endpoints for clinical trials that are reliable, objective, and clinically meaningful. Task Force members agreed that progress in treating sarcopenia will require strengthening of partnerships between academia, industry, and government agencies, and across continents to reach consensus on diagnostic criteria, optimization of clinical trials design, and identification of improved treatment and preventive strategies. In this report, the main results of the Task Force discussion are presented.

Prevalence of sarcopenia in acute hip fracture patients and its influence on short-term clinical outcome

AIM

Current international criteria provide standardized procedures to diagnose sarcopenia in older people. However, to date few data exist on patients with acute disease. The present study was carried out to determine the frequency of sarcopenia in acute hip fracture patients, and its association with their baseline characteristics and prognosis during hospitalization.

METHODS

Data were collected from 509 consecutive patients hospitalized for hip fracture. The European Working Group on Sarcopenia in Older People Criteria for sarcopenia were applied in the first 72 h. Muscle mass was measured by electrical bioimpedance and grip strength by hydraulic dynamometer. Clinical, functional and cognitive characteristics were assessed at baseline and hospital discharge, and their association with the presence of sarcopenia was studied.

RESULTS

A total of 479 patients (94%) met the inclusion criteria. The mean age was 85.3 (SD 6.8 years). The frequency of sarcopenia was 17.1% (12.4% in men, 18.3% in women). Sarcopenia was associated with residence in nursing homes (30.5% vs 19.6%, P = 0.030), older age (86.8, SD 6.2 vs 85.1, SD 6.9 years, P = 0.038), and lower body mass index (23.1, SD 3.6 vs 25.6, SD 4.23, P < 0.001). In the multivariate analysis, only low body mass index was predictive of sarcopenia (OR 0.85, 95% CI 0.80-0.91). Sarcopenia was associated with worse functional prognosis at discharge in the crude analysis (OR 1.88, 95% CI 1.15-3.07), but not in the multivariate analysis (OR 1.68, 95% CI 0.99-2.84).

CONCLUSIONS

Sarcopenia was detected in almost one of five acute hip fracture patients and was associated with lower body mass index, but an association with worse prognosis at discharge could not be confirmed. Geriatr Gerontol Int 2016; 16: 1021-1027.

Body composition in older community-dwelling adults with hip fracture: portable field methods validated by dual-energy X-ray absorptiometry

Ageing is associated with weight loss and subsequently poor health outcomes. The present study assessed agreement between two field methods, bioelectrical impedance spectroscopy (BIS) and corrected arm muscle area (CAMA) for assessment of body composition against dual-energy X-ray absorptiometry (DXA), the reference technique. Agreement between two predictive equations estimating skeletal muscle mass (SMM) from BIS against SMM from DXA was also determined. Assessments occurred at baseline < 14 d post-surgery (n 79), and at 6 months (6M; n 75) and 12 months (12M; n 63) in community-living older adults after surgical treatment for hip fracture. The 95 % limits of agreement (LOA) between BIS and DXA, CAMA and DXA and the equations and DXA were assessed using Bland-Altman analyses. Mean bias and LOA for fat-free mass (FFM) between BIS and DXA were: baseline, 0.7 (-10.9, 12.4) kg; 6M, - 0.5 (-20.7, 19.8) kg; 12M, 0.1 (-8.7, 8.9) kg and for SMM between CAMA and DXA were: baseline, 0.3 (-11.7, 12.3) kg; 6M, 1.3 (-4.5, 7.1) kg; 12M, 0.9 (-5.4, 7.2) kg. Equivalent data for predictive equations against DXA were: equation 1: baseline, 15.1 (-9.5, 20.6) kg; 6M, 17.1 (-12.0, 22.2) kg; 12M, 17.5 (-13.0, 22.0) kg; equation 2: baseline, 12.6 (-7.3, 19.9) kg; 6M, 14.4 (-9.7, 19.1) kg; 12M, 14.8 (-10.7, 18.9) kg. Proportional bias (BIS: β = -0.337, P< 0.001; CAMA: β = -0.294, P< 0.001) was present at baseline but not at 6M or 12 M. Clinicians should be cautious in using these field methods to predict FFM and SMM, particularly in the acute care setting. New predictive equations would be beneficial.

Gentamicin pharmacokinetics in old age and frailty

AIMS

Frailty, a syndrome of decreased physiological reserve that is prevalent in old age, impacts on clinical pharmacology. The aims of the study were to (1) determine whether frailty affects the pharmacokinetics of gentamicin and (2) assess the accuracy of different estimates of body size and renal clearance as estimates of gentamicin pharmacokinetics in older inpatients.

METHODS

This was an observational study of gentamicin pharmacokinetics in a cohort of Australian hospital inpatients aged ≥65 years, who were administered prophylactic intravenous gentamicin.

RESULTS

Of the 31 participants, 14 were frail and 17 non frail on the Reported Edmonton Frail Scale. The mean volume of distribution of gentamicin was 14.8 ± 1.4 l in frail participants and 15.3 ± 2.2 l in non frail (NS). Volume of distribution correlated best with lean bodyweight. Gentamicin clearance was significantly lower in frail participants (46.6 ± 10.7 ml min(-1)) than in non frail (58.2 ± 12.4 ml min(-1), P=0.01). The Cockcroft Gault estimate of creatinine clearance calculated using ideal bodyweight gave the best estimate of gentamicin clearance (mean error -0.15 ml min(-1), 95% CI -2.67, 2.39). The Cockcroft Gault creatinine clearance calculated using actual bodyweight and the estimated glomerular filtration rate from the modified diet in renal disease equation overestimated gentamicin clearance, with mean errors of -10.15 ml min(-1) (95%CI -13.60, -6.71) and -18.86 ml min(-1) (95% CI -22.45, -15.27), respectively. The Cockcroft Gault creatinine clearance calculated using lean bodyweight underestimated gentamicin clearance (mean error 6.54 ml min(-1), 95% CI 4.18, 8.90).

CONCLUSIONS

Frail older people have significantly lower gentamicin clearance than non frail. The best estimate of gentamicin clearance is obtained from the Cockcroft Gault creatinine clearance calculated using ideal bodyweight.