Accuracy of eight-polar bioelectrical impedance analysis for the assessment of total and appendicular body composition in peritoneal dialysis patients

Objective: To establish the accuracy of bioelectrical impedance analysis (BIA) for the assessment of total and appendicular body composition in peritoneal dialysis (PD) patients. Design: Cross-sectional study. Setting: University Nephrology Clinic. Subjects: In all, 20 PD patients and 77 healthy controls matched for gender, age and body mass index. Methods: Whole-body fat-free mass (FFM) and appendicular lean tissue mass (LTM) were measured by dual-energy X-ray absorptiometry. Resistance ( R) of arms, trunk and legs was measured by eight-polar BIA at frequencies of 5, 50, 250 and 500 kHz. Whole-body resistance was calculated as the sum of R of arms, trunk and legs. The resistance index ( RI) was calculated as the ratio between squared height and whole-body or segmental R. Results: RI at 500 kHz was the best predictor of FFM, LTMarm and LTMleg in both PD patients and controls. Equations developed on controls overestimated FFM and LTMarm and underestimated LTMleg when applied to PD patients. Specific equations were thus developed for PD patients. Using these equations, the percent root mean-squared errors of the estimate for PD patients vs controls were 5 vs 6% for FFM, 8 vs 8% for LTMarm and 7 vs 8% for LTMleg. Conclusion: Eight-polar BIA offers accurate estimates of total and appendicular body composition in PD patients, provided that population-specific equations are used

Relationship between body composition and bone mineral content in young and elderly women.

PRIMARY OBJECTIVE: To study the relationship between bone mineral content (BMC), lean tissue mass (LTM) and fat mass (FM) in a large sample of young and elderly women. RESEARCH DESIGN: Cross-sectional. METHODS AND PROCEDURES: BMC, LTM and FM were measured by dual-energy X-ray absorptiometry in 2009 free-dwelling Caucasian women aged 63 +/- 7 years (mean +/- SD; range: 37-88 years). The majority of women were postmenopausal (96%). RESULTS: LTM explained 13% more variance of BMC than FM (R(2)(adj) = 0.39 vs 0.26, p < 0.0001) but weight (Wt) explained 5% more variance of BMC than LTM (R(2)(adj) = 0.44, p < 0.0001). The prediction of BMC obtained from LTM and FM (R(2)(adj)= 0.46, p < 0.0001) was only slightly better than that obtained from Wt. After the effects of age, Wt and height (Ht) on BMC were taken into account by multiple regression, the contribution of LTM and FM to BMC was just one-fifth of that of Wt (R(2)(adj) for full models < or =0.56, p < 0.0001). After a further correction for bone area (BA), the contribution of LTM and FM to BMC was just one-tenth of that of BA and not different from that of Wt and Ht on practical grounds (R(2)(adj) for full models = 0.84, p < 0.0001). Thus, after inter-individual differences in age, Wt, Ht (and bone size) are taken into account, the relationship between body composition and BMC is substantially weakened. CONCLUSIONS: In Caucasian women, (1) LTM is a stronger predictor of BMC than FM, but (2) Wt is a better predictor of BMC than body composition for practical purposes, and (3) Wt and body composition are not able to explain more than 46% of BMC variance

Cross-calibration of eight-polar bioelectrical impedance analysis versus dual-energy X-ray absorptiometry for the assessment of total and appendicular body composition in healthy subjects aged 21-82 years.

Aim: To calibrate eight-polar bioelectrical impedance analysis (BIA) against dual-energy X-ray absorptiometry (DXA) for the assessment of total and appendicular body composition in healthy adults.Research design: A cross-sectional study was carried out.Subjects: Sixty-eight females and 42 males aged 21-82 years participated in the study.Methods: Whole-body fat-free mass (FFM) and appendicular lean tissue mass (LTM) were measured by DXA; resistance (R) of arms, trunk and legs was measured by eight-polar BIA at frequencies of 5, 50, 250 and 500 kHz; whole-body resistance was calculated as the sum R of arms, trunk and legs.Results: The resistance index (RI), i.e. the height(2)/resistance ratio, was the best predictor of FFM and appendicular LTM. As compared with weight (Wt), RI at 500 kHz explained 35% more variance of FFM (R-adj(2) =0.92 vs 0.57), 45% more variance of LTMarm (R-adj(2) = 0.93 vs 0.48) and 36% more variance of LTleg (R-adj(2) = 0.86 vs 0.50) (p &lt; 0.001 for all). The contribution of age to the unexplained variance of FFM and appendicular LTM was nil or negligible and the RI x sex interactions were either not significant or not important on practical grounds. The percent root mean square error of the estimate was 6% for FFM and 8% for LTMarm and LTMleg.Conclusion: Eight-polar BIA offers accurate estimates of total and appendicular body composition. The attractive hypothesis that eight-polar BIA is influenced minimally by age and sex should be tested on larger samples including younger individuals

Nonalcoholic fatty liver disease and aging: epidemiology to management

Nonalcoholic fatty liver disease (NAFLD) is common in the elderly, in whom it carries a more substantial burden of hepatic (nonalcoholic steatohepatitis, cirrhosis and hepatocellular carcinoma) and extra-hepatic manifestations and complications (cardiovascular disease, extrahepatic neoplasms) than in younger age groups. Therefore, proper identification and management of this condition is a major task for clinical geriatricians and geriatric hepatologists. In this paper, the epidemiology and pathophysiology of this condition are reviewed, and a full discussion of the link between NAFLD and the aspects that are peculiar to elderly individuals is provided; these aspects include frailty, multimorbidity, polypharmacy and dementia. The proper treatment strategy will have to consider the peculiarities of geriatric patients, so a multidisciplinary approach is mandatory. Non-pharmacological treatment (diet and physical exercise) has to be tailored individually considering the physical limitations of most elderly people and the need for an adequate caloric supply. Similarly, the choice of drug treatment must carefully balance the benefits and risks in terms of adverse events and pharmacological interactions in the common context of both multiple health conditions and polypharmacy. In conclusion, further epidemiological and pathophysiological insight is warranted. More accurate understanding of the molecular mechanisms of geriatric NAFLD will help in identifying the most appropriate diagnostic and therapeutic approach for individual elderly patients

Age-associated alterations in cholesterol homeostasis: evidence from a cross-sectional study in a Northern Italy population.

BACKGROUND: The modifications of cholesterol metabolism associated with aging are ill-defined. The objective of this study was to define age-associated alterations of the different metabolic pathways controlling cholesterol homeostasis by analyzing circulating sterols. METHODS: We analyzed serum samples collected from 201 adult (75 male, 126 female) subjects within the epidemiological MICOL study (Multicentrica Italiana Colelitiasi). The age range was 38-79 years; 103 had evidence of gallstones. The concentrations of the different sterols, recognized as markers of the main pathways of cholesterol homeostasis, were analyzed by gas chromatography-mass spectrometry, including lathosterol (synthesis), campesterol and sitosterol (absorption), and 7α-hydroxy-4-cholesten-3-one (degradation to bile acids). RESULTS: A significant direct correlation was detected between age and cholesterol levels (r =0.34, P<0.01). The lathosterol/cholesterol ratio was lower in older age quartiles (P<0.05 by analysis of variance), with an inverse correlation between the lathosterol/cholesterol ratio and age (r=-0.32, P<0.01). Such correlation was particularly evident in females. The campesterol/cholesterol and sitosterol/cholesterol ratios were inversely correlated with aging in control, but not in gallstone patients. The levels of 7α-hydroxy-4-cholesten-3-one were not correlated with age. CONCLUSION: These data show a reduction of cholesterol synthesis with aging which is associated with increased circulating cholesterol levels. The finding might be related to a reduced metabolic need for cholesterol in advancing age, leading to a downregulation of the main mechanisms of cholesterol intake in the liver. A different age-related behavior was observed in gallstone-free versus gallstone patients regarding cholesterol absorption. The possible implications in terms of the pharmacological management of hypercholesterolemia in the elderly remain to be defined

Frailty and post-operative delirium influence on functional status in patients with hip fracture: the GIOG 2.0 study

Background: This study analyzes the effect of frailty and Post-Operative Delirium (POD) on the functional status at hospital discharge and at 4-month follow-up in patients with hip fracture (HF). Methods: Multicenter prospective observational study of older patients with HF admitted to 12 Italian Orthogeriatric centers (July 2019-August 2022). POD was assessed using the 4AT. A 26-item Frailty Index (FI) was created using data collected on admission. The outcome measures were Cumulated Ambulation Score (CAS) ≤ 2 at discharge and a telephone-administered CAS ≤ 2 after 4&nbsp;months. Poisson regression models were used to assess the effect of frailty and POD on outcomes. Results: 984 patients (median age 84&nbsp;years, IQR = 79-89) were recruited: 480 (48.7%) were frail at admission, 311 (31.6%) developed POD, and 158 (15.6%) had both frailty and POD. In a robust Poisson regression, frailty alone (Relative Risk, RR = 1.56, 95% Confidence Intervals, CI 1.19-2.04, p = 0.001) and its combination with POD (RR = 2.57, 95% CI 2.02-3.26, p &lt; 0.001) were associated with poor functional status at discharge. At 4-month follow-up, the combination of frailty with POD (RR 3.65, 95% CI 1.85-7.2, p &lt; 0.001) increased the risk of poor outcome more than frailty alone (RR 2.38, 95% CI 1.21-4.66, p &lt; 0.001). Conclusions: POD development exacerbates the negative effect that frailty exerts on functional outcomes in HF patients

Adherence to antithrombotic therapy guidelines improves mortality among elderly patients with atrial fibrillation: insights from the REPOSI study

Atrial fibrillation (AF) is associated with a substantial risk of thromboembolism and mortality, significantly reduced by oral anticoagulation. Adherence to guidelines may lower the risks for both all cause and cardiovascular (CV) deaths. Methods: Our objective was to evaluate if antithrombotic prophylaxis according to the 2012 European Society of Cardiology (ESC) guidelines is associated to a lower rate of adverse outcomes. Data were obtained from REPOSI; a prospective observational study enrolling inpatients aged ≥65 years. Patients enrolled in 2012 and 2014 discharged with an AF diagnosis were analysed. Results: Among 2535 patients, 558 (22.0 %) were discharged with a diagnosis of AF. Based on ESC guidelines, 40.9 % of patients were on guideline-adherent thromboprophylaxis, 6.8 % were overtreated, and 52.3 % were undertreated. Logistic analysis showed that increasing age (p = 0.01), heart failure (p = 0.04), coronary artery disease (p = 0.013), peripheral arterial disease (p = 0.03) and concomitant cancer (p = 0.003) were associated with non-adherence to guidelines. Specifically, undertreatment was significantly associated with increasing age (p = 0.001) and cancer (p < 0.001), and inversely associated with HF (p = 0.023). AF patients who were guideline adherent had a lower rate of both all-cause death (p = 0.007) and CV death (p = 0.024) compared to those non-adherent. Kaplan–Meier analysis showed that guideline-adherent patients had a lower cumulative risk for both all-cause (p = 0.002) and CV deaths (p = 0.011). On Cox regression analysis, guideline adherence was independently associated with a lower risk of all-cause and CV deaths (p = 0.019 and p = 0.006). Conclusions: Non-adherence to guidelines is highly prevalent among elderly AF patients, despite guideline-adherent treatment being independently associated with lower risk of all-cause and CV deaths. Efforts to improve guideline adherence would lead to better outcomes for elderly AF patient

Safety and tolerability of Tilt Testing and Carotid Sinus Massage in the octogenarians

OBJECTIVE: to evaluate the safety and tolerability of Tilt Testing (TT) and Carotid Sinus Massage (CSM) in octogenarians with unexplained syncope. METHODS: patients consecutively referred for transient loss of consciousness to the 'Syncope Units' of three hospitals were enrolled. TT and CSM were performed according to the European Society of Cardiology guidelines on syncope. Complications were evaluated in each group. An early interruption of TT was defined as 'intolerance' and considered as a non-diagnostic response. RESULTS: one thousand four hundred and one patients were enrolled (mean age 72 \ub1 16 years, male 40.8%). Six hundred and ninety-four patients (49.5%) were 80 years old or older (mean age 83 \ub1 3 years) and 707 (50.5%) were younger (mean age 60 \ub1 17 years). Complications after TT occurred in 4.5% of older patients and in 2.1% of the younger ones (P = 0.01). All complications were 'minor/moderate', as prolonged hypotension, observed in 3c3% of patients 6580 years. Major complications such as sustained ventricular tachycardia, ventricular fibrillation, asystole requiring cardiac massage, transient ischaemic attack, stroke and death were not observed in any patient. The presence of orthostatic hypotension and the mean number of syncopal episodes were predictors of TT complications. Intolerance was reported in 2.4% of older patients and 1% of the younger ones (P = 0.08), mainly due to orthostatic intolerance. No complications occurred after CSM. CONCLUSIONS: TT and CSM appear to be safe and well tolerated in octogenarians, who should not be excluded by age from the diagnostic work-up of syncope