Kristina Norman

Hand grip strength: Outcome predictor and marker of nutritional status

BACKGROUND & AIMS Among all muscle function tests, measurement of hand grip strength has gained attention as a simple, non-invasive marker of muscle strength of upper extremities, well suitable for clinical use. This review outlines the prognostic relevance of grip strength in various clinical and epidemiologic settings and investigates its suitability as marker of nutritional status in cross-sectional as well as intervention studies. METHODS Studies investigating grip strength as prognostic marker or nutritional parameter in cross-sectional or intervention studies were summarized. RESULTS AND CONCLUSIONS Numerous clinical and epidemiological studies have shown the predictive potential of hand grip strength regarding short and long-term mortality and morbidity. In patients, impaired grip strength is an indicator of increased postoperative complications, increased length of hospitalization, higher rehospitalisation rate and decreased physical status. In elderly in particular, loss of grip strength implies loss of independence. Epidemiological studies have moreover demonstrated that low grip strength in healthy adults predicts increased risk of functional limitations and disability in higher age as well as all-cause mortality. As muscle function reacts early to nutritional deprivation, hand grip strength has also become a popular marker of nutritional status and is increasingly being employed as outcome variable in nutritional intervention studies.

Bioelectrical phase angle and impedance vector analysis – Clinical relevance and applicability of impedance parameters

BACKGROUND & AIMS The use of phase angle (PhA) and raw parameters of bioelectrical impedance analysis (BIA) has gained attention as alternative to conventional error-prone calculation of body composition in disease. This review investigates the clinical relevance and applicability of PhA and Bioelectrical Impedance Vector Analysis (BIVA) which uses the plot of resistance and reactance normalized per height. METHODS A comprehensive literature search was conducted using Medline identifying studies relevant to this review until March 2011. We included studies on the use of PhA or BIVA derived from tetrapolar BIA in out- and in-patient settings or institutionalized elderly. RESULTS Numerous studies have proven the prognostic impact of PhA regarding mortality or postoperative complications in different clinical settings. BIVA has been shown to provide information about hydration and body cell mass and therefore allows assessment of patients in whom calculation of body composition fails due to altered hydration. Reference values exist for PhA and BIVA facilitating interpretation of data. CONCLUSION PhA, a superior prognostic marker, should be considered as a screening tool for the identification of risk patients with impaired nutritional and functional status, BIVA is recommended for further nutritional assessment and monitoring, in particular when calculation of body composition is not feasible.

Cutoff percentiles of bioelectrical phase angle predict functionality, quality of life, and mortality in patients with cancer

BACKGROUND The bioelectrical phase angle has shown predictive potential in various diseases, but general cutoffs are lacking in the clinical setting. OBJECTIVES This study evaluated the prognostic value of the fifth percentile of sex-, age-, and body mass index-stratified phase angle reference values in patients with cancer with respect to nutritional and functional status, quality of life, and 6-mo mortality. In a second step, we also studied the effect of the standardized phase angle (with a z score to determine individual deviations from the population average) on these variables. DESIGN A total of 399 patients with cancer were studied. Phase angle was obtained with bioelectrical impedance analysis; muscle function was assessed by handgrip strength and peak expiratory flow. Quality of life was determined by the European Organization for Research and Treatment of Cancer questionnaire. Nutritional status was assessed by using Subjective Global Assessment. Survival of patients was documented after 6 mo. RESULTS Patients with a phase angle of less than the fifth reference percentile had significantly lower nutritional and functional status, impaired quality of life (P lt 0.0001), and increased mortality (P lt 0.001). The standardized phase angle emerged as a significant predictor for malnutrition and impaired functional status in generalized linear model regression analyses. It was also a stronger indicator of 6-mo survival than were malnutrition and disease severity in the Cox regression model (P lt 0.0001) and according to the receiver operating characteristic curve. CONCLUSIONS The standardized phase angle is an independent predictor for impaired nutritional and functional status and survival. The fifth phase angle reference percentile is a simple and prognostically relevant cutoff for detection of patients with cancer at risk for these factors.

Malnutrition and impaired muscle strength in patients with Crohn's disease and ulcerative colitis in remission

OBJECTIVE This prospective, controlled, and multicentric study evaluated nutritional status, body composition, muscle strength, and quality of life in patients with inflammatory bowel disease in clinical remission. In addition, possible effects of gender, malnutrition, inflammation, and previous prednisolone therapy were investigated. METHODS Nutritional status (subjective global assessment [SGA], body mass index, albumin, trace elements), body composition (bioelectrical impedance analysis, anthropometry), handgrip strength, and quality of life were assessed in 94 patients with Crohns disease (CD; 61 female and 33 male, Crohns Disease Activity Index 71 +/- 47), 50 patients with ulcerative colitis (UC; 33 female and 17 male, Ulcerative Colitis Activity Index 3.1 +/- 1.5), and 61 healthy control subjects (41 female and 20 male) from centers in Berlin, Vienna, and Bari. For further analysis of body composition, 47 well-nourished patients with inflammatory bowel disease were pair-matched by body mass index, sex, and age to healthy controls. Data are presented as median (25th-75th percentile). RESULTS Most patients with inflammatory bowel disease (74%) were well nourished according to the SGA, body mass index, and serum albumin. However, body composition analysis demonstrated a decrease in body cell mass (BCM) in patients with CD (23.1 kg, 20.8-28.7, P = 0.021) and UC (22.6 kg, 21.0-28.0, P = 0.041) compared with controls (25.0 kg, 22.0-32.5). Handgrip strength correlated with BCM (r = 0.703, P = 0.001) and was decreased in patients with CD (32.8 kg, 26.0-41.1, P = 0.005) and UC (31.0 kg, 27.3-37.8, P = 0.001) compared with controls (36.0 kg, 31.0-52.0). The alterations were seen even in patients classified as well nourished. BCM was lower in patients with moderately increased serum C-reactive protein levels compared with patients with normal levels. CONCLUSION In CD and UC, selected micronutrient deficits and loss of BCM and muscle strength are frequent in remission and cannot be detected by standard malnutrition screening.

Effects of food fortification on nutritional and functional status in frail elderly nursing home residents at risk of malnutrition

OBJECTIVE Malnutrition is a frequent problem in the elderly and is associated with an impaired functional status and higher morbidity and mortality. In this study we evaluated the effect of a 12-wk nutritional intervention with fortified food on nutritional and functional status in nursing home residents at risk of malnutrition. METHODS Nutritional status was assessed with the Mini Nutritional Assessment. Body composition was measured with bioelectrical impedance analysis. Functional status was assessed with handgrip strength, peak flow, the Barthel Index, and the Physical Functioning component of the Short Form 36 questionnaire. The residents were assigned to a group receiving the standard food of the nursing home or a group with a protein- and energy-enriched diet and snacks. RESULTS Sixty-five nursing home residents were included; 62 were at nutritional risk and 3 were severely malnourished according to the Mini Nutritional Assessment. Protein intake was significantly higher in the group on the enriched diet, whereas energy intake did not differ from the group on the standard diet. Both groups significantly improved most nutritional and body composition parameters during the intervention period. We did not observe convincing improvements in muscle function. Furthermore, the Barthel Index and the Physical Functioning component of the Short Form 36 questionnaire declined in all participants. CONCLUSION Standard food in this nursing home provided sufficient energy and macronutrients. Provision of snacks was not effective in increasing energy intake. Although nutritional status improved, functional status did not increase as a consequence. Functional frailty in this study population seems to be influenced more by age-related morbidity and immobilization than by nutritional intake.

Malnutrition and depression in the institutionalised elderly

Malnutrition and depression are highly prevalent in the institutionalised elderly and can lead to unfavourable outcomes. The aim of the present study was to assess associations between nutritional status and depressive symptoms and to explore their impact on self-caring capacity and quality of life (QoL) in elderly nursing-home residents (NHR). We conducted a cross-sectional study with 114 NHR (eighty-six female) with a mean age of 84.6 (sd 9.1) years. Nutritional status was assessed with the Mini Nutritional Assessment (MNA). Depressive symptoms were rated with the Geriatric Depression Scale (GDS). Self-caring capacity was measured with the Barthel index (BI) and QoL was assessed with the short-form thirty-six-item (SF-36) questionnaire. Of the NHR, twenty-six (22.8 %) were malnourished according to the MNA and sixty-six (57.9 %) were at nutritional risk. Of the residents, seventy-five could be assessed with the GDS, whereof sixteen (21.3 %) had major and twenty-six (34.7 %) had minor depressive symptoms. GDS scores tended to be higher in patients with impaired nutritional status (5.4 (sd 3.6) in well-nourished subjects and 6.9 (sd 3.2) in residents with malnutrition or at risk of malnutrition). The MNA correlated significantly with the GDS (r - 0.313; P = 0.006) and the GDS emerged as the only independent risk factor for malnutrition in a multiple regression analysis, whereas age, sex, care level, number of prescriptions and self-caring capacity had no influence. The BI was not reduced in patients with a high GDS. QoL was affected in malnourished residents as well as in study participants with depressive symptoms. The results of the present study point towards an association between malnutrition and depressive symptoms. However, the relationship is complex and it remains unclear whether depression in NHR is the cause or consequence of impaired nutritional status. Further studies are needed to identify the direction of this relationship and to assess the effect of depression treatment on nutritional and functional status as well as on QoL.

Circulating adipokines and the protective effects of hyperinsulinemia in inflammatory bowel disease.

OBJECTIVE Adipokines are fat-derived hormones and cytokines with immune-modulating and metabolic properties. Most of them are associated with insulin resistance. The aim of the present investigation was to evaluate circulating levels of adipokines and glucose homeostasis in patients with inflammatory bowel disease (IBD) and to evaluate possible associations with the course and characteristics of the disease. METHODS Serum leptin, resistin, visfatin, retinol-binding protein-4, adiponectin, glucose, insulin, and inflammatory parameters were analyzed in 93 patients with inactive IBD (49 with Crohns disease [CD], 44 with ulcerative colitis [UC]), 35 patients with active IBD (18 with CD, 17 with UC), and 37 age- and body mass index-matched healthy controls. Ninety-two patients were followed for 6 mo. RESULTS Leptin was similar in patients with IBD and controls, whereas resistin and visfatin were increased in patients with active disease but not in those in remission. In active and inactive disease, adiponectin was decreased (P < 0.001) and retinol-binding protein-4 was increased (P < 0.001) compared with controls. About 60% of patients with IBD showed increased levels of insulin, whereas serum glucose remained normal, resulting in increased homeostasis model assessment values in most patients. Hyperinsulinemia was associated with the decrease in adiponectin (r = -0.572, P < 0.001) and proved to be an independent protective factor for 6-mo maintenance of remission (P = 0.016). CONCLUSION IBD led to largely similar alterations in circulating adipokines and hyperinsulinemia in patients with CD and those with UC. The unexpected protective effect of hyperinsulinemia on relapse rate denotes the role of the metabolic-inflammatory response as a modulator in IBD.

Bioimpedance vector analysis as a measure of muscle function

INTRODUCTION The impedance vector produced by an alternating current in the bioimpedance analysis can be seen as a standardised test of cellular mass and function since reactance is believed to reflect the mass and integrity of cell membranes. This study investigated the association between resistance and reactance normalised for height (R/H and Xc/H), and muscle function as assessed by hand grip strength. METHODS 363 patients (172 male, 191 female) from Berlin and Copenhagen were included in the analysis. Whole body impedance was determined by BIA 2000M (Berlin) or EFG2.0 (Copenhagen). Hand grip strength was measured with Digimax electronic hand dynamometer (Berlin) or Jamar dynamometer (Copenhagen). The general linear model was used to assess the association between R/H, Xc/H and hand grip strength. RESULTS We observed a significant association between the impedance parameters R/H and Xc/H and hand grip strength after adjusting for confounding variables (hand grip strength= -36.9 - 0.063 x R/H + 0.573 x Xc/H + 40.7 x Height + 0.115 x Weight - 0.09 x Age + 3.41 (gender=male) + 1.87 (Centre Berlin); Weight: P=0.04, all other coefficients: P<0.0005. r(2)=0.708). CONCLUSIONS The impedance parameters R/H and Xc/H are related to hand grip strength and might therefore be used as a cooperation-independent method to reproducibly assess muscle function.

Determinants of hand grip strength, knee extension strength and functional status in cancer patients

BACKGROUND & AIMS Decreased functionality and muscle weakness are prominent features in cancer patients. We investigated determinants of muscle function assessed by hand grip and knee extension strength as well as functional status in cancer patients. METHODS 189 consecutively admitted cancer patients (age 60.8 ± 12.7 years, 96 male) were recruited. Muscle function was assessed by hand grip and knee extension strength, and percentage of anticipated peak expiratory flow (%PEF). Functional status was determined by the EORTC questionnaire of quality of life. Nutritional status was assessed with Subjective Global Assessment (SGA). Age, gender, SGA, body mass index, clinical variables such as cancer location, presence of distant metastases, tumour burden according to TNM stage, UICC stage, number of drugs per day, number of comorbidities, type of treatment and depression were investigated as potential risk factors for muscle weakness and impaired functional status in a multiple regression analysis. RESULTS 80 patients (39 male) were classified moderately or severely malnourished. Malnutrition also emerged as an independent determinant for hand grip (estimated effect size 11%, p < 0.01), knee extension strength (estimated effect size 12%, p < 0.001), and peak expiratory flow (estimated effect size 30%, p < 0.008) and functional status (estimated effect size 19.4%, p < 0.001) next to age and gender, which were the strongest predictors. Among the disease parameters, only amount of daily medication exhibited a significant influence on knee extension strength. CONCLUSIONS Malnutrition is a disease independent risk factor for reduced muscle strength and functional status in cancer patients. Treatment of malnutrition might therefore also restore muscle strength.

Determinants of bioelectrical phase angle in disease

Phase angle (PhA), a parameter of bioelectrical impedance analysis, is a well-known predictor of morbidity and mortality in various diseases. The causes of decreased PhA are, however, not yet completely understood. We therefore investigated determinants of PhA in 777 hospitalised patients in a retrospective analysis. PhA was assessed by bioelectrical impedance analysis at 50 KHz. Subjective global assessment (SGA) was used to evaluate nutritional status. Age, sex, BMI as well as nutritional status (SGA), benign or malignant disease and C-reactive protein (CRP) were investigated as potential determinants of PhA and standardised PhA (SPhA) = (observed PhA - mean PhA of reference values)/standard deviation of reference values in a general linear model regression analysis. Next to age (estimated effect size, 46·6%; P<0·0001), malnutrition (39·1%; P<0·0001) emerged as a major PhA determinant in our study population. Moreover, sex (6·4%; P<0·0001), CRP (4·4%; P<0·0001) and BMI (3·5%; P < 0·0001) exhibited a significant influence on PhA, whereas malignant disease showed no significant effect in this model. The only significant determinants of SPhA were malnutrition (85·4%; P<0·0001) and inflammation (9·6 %; P<0·0001). In conclusion, next to the established predictors, malnutrition and inflammation have a strong impact on PhA in sick individuals, which partly explains its prognostic power. When investigating the SPhA, only malnutrition and inflammation were found to be significant predictors, as a result of which the SPhA is considered a more suitable indicator of nutritional and health status.