Maryam Pourhassan

Assessment and definition of lean body mass deficiency in the elderly.

Although the effect of age on body composition has been intensively discussed during the past 20 years, we do not have a uniform definition of sarcopenia. A suitable definition of low, lean body mass should be based on magnetic resonance imaging (MRI) estimates of muscle mass. Using recent MRI data of a population of 446 healthy free-living Caucasian volunteers (247 females, 199 males) age 18–78 years, a low skeletal muscle mass and sarcopenia were defined as a skeletal muscle mass >1 and >2 s.d. below the mean value obeserved in younger adults at age 18–39 years. The cutoffs for low muscle mass according to the skeletal muscle index (skeletal muscle mass/(height)2) or the appendicular skeletal muscle mass index (skeletal muscle mass of the limbs/(height)2) were 6.75 or 4.36u2009kg/m2 for females and 8.67 or 5.54u2009kg/m2 for males, respectively. On the basis of these cutoffs, prevalences of sarcopenia in the group of adults at >60 years are calculated to be 29% in females and 19.0% in males. Faced with different sarcopenic phenotypes (that is, sarcopenia related to frailty and osteopenia; sarcopenic obesity related to metabolic risks; cachexia related to wasting diseases), future definitions of sarcopenia should be extended to the relations between (i) muscle mass and adipose tissue and (ii) muscle mass and bone mass. Suitable cutoffs should be based on the associations between estimates of body compositions and metabolic risks (for axample, insulin resistance), inflammation and muscle function (that is, muscle strength).

Impact of body-composition methodology on the composition of weight loss and weight gain

Background/Objectives:We intended to (i) to compare the composition of weight loss and weight gain using densitometry, deuterium dilution (D2O), dual-energy X-ray absorptiometry (DXA), magnetic resonance imaging (MRI) and the four-compartment (4C) model and (ii) to compare regional changes in fat mass (FM), fat-free mass (FFM) and skeletal muscle as assessed by DXA and MRI.Subjects/Methods:Eighty-three study participants aged between 21 and 58 years with a body mass index range of 20.2–46.8u2009kg/m2 had been assessed at two different occasions with a mean follow-up between 23.5 and 43.5 months. Body-weight changes within < 3% were considered as weight stable, a gain or a loss of >3% of initial weight was considered as a significant weight change.Results:There was a considerable bias between the body-composition data obtained by the individual methods. When compared with the 4C model, mean bias of D2O and densitometry was explained by the erroneous assumption of a constant hydration of FFM, thus, changes in FM were underestimated by D2O but overestimated by densitometry. Because hydration does not normalize after weight loss, all two-component models have a systematic error in weight-reduced subjects. The bias between 4C model and DXA was mainly explained by FM% at baseline, whereas FFM hydration contributed to additional 5%. As to the regional changes in body composition, DXA data had a considerable bias and, thus, cannot replace MRI.Conclusions:To assess changes in body composition associated with weight changes, only the 4C model and MRI can be used with confidence.

Quantification of whole-body and segmental skeletal muscle mass using phase-sensitive 8-electrode medical bioelectrical impedance devices

Background/Objectives:Bioelectrical impedance analysis (BIA) provides noninvasive measures of skeletal muscle mass (SMM) and visceral adipose tissue (VAT). This study (i) analyzes the impact of conventional wrist-ankle vs segmental technology and standing vs supine position on BIA equations and (ii) compares BIA validation against magnetic resonance imaging (MRI) and dual X-ray absorptiometry (DXA).Subjects/Methods:One hundred and thirty-six healthy Caucasian adults (70 men, 66 women; age 40±12 years) were measured by a phase-sensitive multifrequency BIA (seca medical body composition analyzers 515 and 525). Multiple stepwise regression analysis was used to generate prediction equations. Accuracy was tested vs MRI or DXA in an independent multiethnic population.Results:Variance explained by segmental BIA equations ranged between 97% for total SMMMRI, 91–94% for limb SMMMRI and 80–81% for VAT with no differences between supine and standing position. When compared with segmental measurements using conventional wrist-ankle technology. the relationship between measured and predicted SMM was slightly deteriorated (r=0.98 vs r=0.99, P<0.05). Although BIA results correctly identified ethnic differences in muscularity and visceral adiposity, the comparison of bias revealed some ethnical effects on the accuracy of BIA equations. The differences between LSTDXA and SMMMRI at the arms and legs were sizeable and increased with increasing body mass index.Conclusions:A high accuracy of phase-sensitive BIA was observed with no difference in goodness of fit between different positions but an improved prediction with segmental compared with conventional wrist-ankle measurement. A correction factor for certain ethnicities may be required. When compared with DXA MRI-based BIA equations are more accurate for predicting muscle mass.

Risk factors of refeeding syndrome in malnourished older hospitalized patients

BACKGROUND & AIMSnDespite the high prevalence of malnutrition among older hospitalized persons, it is unknown how many of these malnourished patients are at risk of developing the refeeding syndrome (RFS). In this study, we sought to compare the prevalence and severity of malnutrition among older hospitalized patients with prevalence of known risk factors of RFS.nnnMETHODSnThis cross-sectional multicenter-study investigated older participants who were consecutively admitted to the geriatric acute care ward. Malnutrition screening was conducted using Nutritional Risk Screening (NRS-2002), Malnutrition Universal Screening Tool (MUST) and Mini Nutritional Assessment-Short Form (MNA-SF). The National Institute for Health and Clinical Excellence (NICE) criteria were applied for assessing patients at risk of RFS. Weight and height were measured. Degree of weight loss (WL) was obtained by interview. Serum phosphate, magnesium, potassium, sodium, calcium, creatinine and urea were analyzed according to standard procedures.nnnRESULTSnThe study group comprised 342 participants (222 females) with a mean age of 83.1xa0±xa06.8 and BMI range of 14.7-43.6xa0kg/m2. More participants were assessed at risk of malnutrition using NRS-2002 (nxa0=xa0253, 74.0%) compared to MUST (nxa0=xa0170, 49.7%) and MNA-SF (nxa0=xa0191, 55.8%). Of total participants, 239 (69.9%; 157 females) were considered to be at risk of RFS. Based on NRS-2002, 75.9% (nxa0=xa0192) of patients at risk of malnutrition are at risk of RFS whereas according to MUST and MNA-SF, 85.9% (nxa0=xa0146) and 69.1% (nxa0=xa0132) of patients at risk of malnutrition are exposed to high risk of RFS, respectively. In addition, the prevalence of risk of RFS is significantly increased with higher score of NRS-2002 and MUST and lower score of MNA-SF. In a stepwise multiple regression analysis, disease severity (38.2%), WL in 3 months (20.3%) and BMI (33.3%) mainly explained variance in NRS-2002, MUST and MNA-SF scores, respectively, in patients with risk of RFS.nnnCONCLUSIONnNearly three-quarters of geriatric hospitalized patients with risk of malnutrition demonstrated significant risk of RFS. Therefore, additional screening for risk of RFS in patients screened for malnutrition appears to be abdicable among this population.

Impact of weight loss-associated changes in detailed body composition as assessed by whole-body MRI on plasma insulin levels and homeostatis model assessment index.

Background/Objectives:We assessed the effect of weight loss-associated changes in detailed body composition on plasma insulin levels and homeostatic model assessment (HOMA) index to calculate the magnitude of reduction in different adipose tissue depots required to improve insulin sensitivity.SubjectS/Methods:A total of 50 subjects aged 20–69 years were studied. The participants were compiled from low-calorie diet interventions and bariatric surgery and differed in their baseline body mass index (BMI; range 21.6–54.4u2009kg/m2) and degree of weight losses (range −3.3 to −56.9u2009kg). Detailed body composition and liver fat were measured using whole-body magnetic resonance imaging (MRI). Insulin resistance was assessed by HOMA.Results:Mean body weight decreased by −16.0±13.6u2009kg. Significant changes were observed in total adipose tissue (TATMRI, range −0.5 to −36.0u2009kg), total subcutaneous adipose tissue (SATMRI), visceral adipose tissue (VATMRI), skeletal muscle, liver fat, plasma insulin levels and HOMA. Decreases in insulin and HOMA were correlated with reductions in TATMRI, SATMRI, VATMRI (just with HOMA) and liver fat. Losses of 2.9 and 6.5u2009kg body weight, 2.0 and 5.0u2009kg TATMRI as well as 1.6 and 6% liver fat were required to decrease plasma insulin levels by 1u2009μU/ml and HOMAadjusted for baseline HOMA by 1 point. Multiple regression analysis showed that baseline liver fat and changes in liver fat explained 49.7% and 55.1% of the variance in weight loss-associated changes in plasma insulin and HOMA, respectively.Conclusions:Decreases of adipose tissues and liver fat are the major determinants of reduction in plasma insulin levels and improvement in HOMA index.

Definition of new cut‐offs of BMI and waist circumference based on body composition and insulin resistance: differences between children, adolescents and adults

This study aims to determine associations between anthropometric traits, regional fat depots and insulin resistance in children, adolescents and adults to define new cut‐offs of body mass index (BMI) or waist circumference (WC).

Association between fat mass, adipose tissue, fat fraction per adipose tissue, and metabolic risks: a cross-sectional study in normal, overweight, and obese adults

Background/objectivesWe investigated whether fat mass (FM) and total adipose tissue (TAT) can be used interchangeably and FM per TAT adds to metabolic risk assessment.Subjects/methodsCross-sectional data were assessed in 377 adults (aged 18–60 years; 51.2% women). FM was measured by either 4-compartment (4C) model or quantitative magnetic resonance (QMR); total-, subcutaneous- and visceral adipose tissue (TAT, SAT, VAT), and liver fat by whole-body MRI; leptin, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), C-reactive protein (CRP), and triglycerides; resting energy expenditure and respiratory quotient by indirect calorimetry were determined. Correlations and stepwise multivariate regression analyses were performed.ResultsFM4C and FMQMR were associated with TAT (r4Cu2009=u20090.96, rQMRu2009=u20090.99) with a mean FM per TAT of 0.85 and 1.01, respectively. Regardless of adiposity, there was a considerable inter-individual variance of FM/TAT-ratio (FM4C/TAT-ratio: 0.77–0.94; FMQMR/TAT-ratio: 0.89–1.10). Both, FM4C and TAT were associated with metabolic risks. Further, FM4C/TAT-ratio was positively related to leptin but inversely with CRP. There was no association between FM4C/TAT-ratio and VAT/SAT or liver fat. FM4C/TAT-ratio added to the variance of leptin and CRP.ConclusionsIndependent of FM or TAT, FM4C/TAT-ratio adds to metabolic risk assessment. Therefore, the interchangeable use of FM and TAT to assess metabolic risks is questionable as both parameters may complement each other.

Seasonal variation in vitamin d status among frail older hospitalized patients

Background and objectivesSeasonal variation in 25-hydroxyvitamin D [25(OH)D] levels is the result of sunlight dependent skin synthesis of vitamin D. However, its presence is not studied in frail older hospitalized patients. We sought to investigate whether seasonal variation in 25(OH)D levels is evident among these patients.Design and settingThis study investigated older participants who were consecutively admitted between February 2015 and December 2016 to the geriatric acute care ward. Results of routine measurements of 25(OH)D at hospital admission were retrospectively analyzed and stratified according to months and seasons. Previous intake of vitamin D supplementation was derived from the patients’ medical records.ResultsThe study group comprised 679 participants (mean age 82.1±8.2; 457 females), of which 78% had vitamin D deficiency. Older individuals not taking vitamin D supplements had a lower mean serum 25(OH)D than those receiving supplements. Of those patients with no vitamin D supplementation, 87.0% were vitamin D deficient and only 5% showing sufficient vitamin 25(OH)D. Further, there were neither monthly nor seasonal variations in vitamin 25(OH)D levels among these patients and their vitamin D levels stayed far below the recommended threshold of 20 ng/ml across the seasons.ConclusionVitamin D deficiency was very prevalent in the subgroup of older hospitalized patients without vitamin D supplementation, irrespective of season. Since no seasonal variations in mean 25(OH)D levels was observed, sunlight dependent skin synthesis is unlikely to contribute to vitamin D status in these patients. Supplementation seems to be necessary to maintain desirable vitamin D levels among this population throughout the year.

Impact of Sarcopenia on One-Year Mortality Among Older Hospitalized Patients with Impaired Mobility

ObjectivesHowever, the information regarding the impact of sarcopenia on mortality in older individuals is rising, there is a lack of knowledge concerning this issue among geriatric hospitalized patients. Therefore, aim of the present study was to investigate the associations between sarcopenia and 1-year mortality in a prospectively recruited sample of geriatric inpatients with different mobility and dependency status.Design and settingSarcopenia was diagnosed using the criteria of the European Working Group on Sarcopenia in Older People (EWGSOP). Hand grip strength and skeletal muscle mass were measured using Jamar dynamometer and bioelectrical impedance analysis, respectively. Physical function was assessed with the Short Physical Performance Battery. Dependency status was defined by Barthel-Index (BI). Mobility limitation was defined according to walking ability as described in BI. The survival status was ascertained by telephone interview.ResultsThe recruited population comprised 198 patients from a geriatric acute ward with a mean age of 82.8 ± 5.9 (70.2% females). 50 (25.3%) patients had sarcopenia, while 148 (74.7%) had no sarcopenia. 14 (28%) patients died among sarcopenic subjects compared with 28 (19%) non-sarcopenic subjects (P=0.229). After adjustment for potential confounders, sarcopenia was associated with increased mortality among patients with limited mobility prior to admission (n=138, hazard ratio, HR: 2.52, 95% CI: 1.17-5.44) and at time of discharge (n=162, HR: 1.93, 95% CI: 0.67-3.22). In a sub-group of patients with pre-admission BI<60 (n=45), <70 (n=73) and <80 (n=108), the risk of death was 3.63, 2.80 and 2.55 times higher in sarcopenic patients, respectively. In contrast, no significant relationships were observed between sarcopenia and mortality across the different scores of BI during admission and at time of discharge.ConclusionSarcopenia is significantly associated with higher risk of mortality among sub-groups of older patients with limited mobility and impaired functional status, independently of age and other clinical variables.

The Impact of Dysphagia on Mortality of Nursing Home Residents: Results From the nutritionDay Project

OBJECTIVESnDysphagia is a frequent finding in nursing home residents. The aim of this study is to evaluate the association of dysphagia and mortality in nursing home residents and identify further risk factors for mortality in residents with dysphagia.nnnDESIGNnOne-day, annually repeated cross-sectional study, evaluating the nutritional situation of nursing home residents with 6-month mortality as outcome.nnnSETTINGn191 nursing homes from 14 countries in Europe and the United States participating in the nutritionDay study between 2007 andxa02012.nnnPARTICIPANTSnData of all nursing home residents in the nutritionDay study aged 65xa0years or older with available information about dysphagia and outcome were analyzed.nnnMEASUREMENTSnResidents characteristics and mortality rate were calculated by group comparison, and mortality risk was calculated by multivariate regression analysis with adjustment for potential confounding factors.nnnRESULTSn10,185 residents (78% female) with a mean age of 85xa0±xa08.1xa0years were included in the analysis. Dysphagia was reported in 15.4% of residents. The 6-month mortality of residents with dysphagia was significantly higher than of those without dysphagia (24.7% vs 11.9%; Pxa0<xa0.001). The multivariate regression analysis revealed dysphagia [odds ratio (OR) 1.44, 95% confidence interval (CI) 1.24-1.68, Pxa0<xa0.001] along with body mass index <20 (OR 1.78, 95% CI 1.55-2.03, Pxa0<xa0.001) and weight loss >5xa0kg (OR 1.61, 95% CI 1.37-1.88, Pxa0<xa0.001) as independent and significant risk factors for mortality. Because of significant interaction, a disproportionately high mortality of 38.9% was found in residents with dysphagia accompanied by previous weight loss >5xa0kg (OR for interaction 1.44; 95% CI 1.03-2.01; Pxa0=xa0.032). Tube feeding was reported in 14.6% of residents with dysphagia. The mortality rate of dysphagic residents receiving tube feeding vs those who were not was not significantly different (21.4% vs 25.3%; Pxa0=xa0.244).nnnCONCLUSIONnIn this nutritionDay study, dysphagia was identified as an independent risk factor for mortality in nursing home residents. Residents with dysphagia accompanied by weight loss are at a particularly high risk of mortality and should therefore receive special attention.