Vitamin D: A magic bullet or a myth?

The interest in Vitamin D (Vit D) is increased after the finding of Vit D receptors in many different cells. This led to the hypothesis that Vit D may have more impact on human health than its role in bone health. Epidemiological studies found associations between low plasma levels of Vit D and the prevalence of many diseases. However, Large RCTs did not find convincing evidence for a positive effect of Vit D supplementation on cancer, cardiovascular disease, auto-immune disease and inflammatory diseases. In this review, the results are described of a literature search regarding the relationship between Vit D status and different diseases. Pubmed was used to find systematic reviews of observational studies describing the association between Vit D status, diseases (cancer, coronary heart diseases, auto-immune diseases, sepsis) and mortality. Subsequently, a search was performed for RCTs and the results of large RCTs are described. Studies with a positive intervention effect on primary or secondary outcome variables are summarized. No exclusion criteria were used. The metabolism of Vit D is reviewed, its endogenous production and the intake from food, its activation and transport in the body. The article addresses the effects of diseases on the metabolism of Vit D with special focus on the role of Vit D Binding Protein and its effects on assessing Vit D status. Studies addressing the association between vitamin D status and cancer, cardiovascular diseases, auto-immune diseases, inflammation and severe illness are reviewed. A search for RCTs with positive effects of Vit D supplementation on different diseases yielded only a few studies. The vast majority of RCTs showed no significant positive effects. The presumed high prevalence of Vit D deficiency is questioned based on these results and on altered concentrations of Vit D binding protein, leading to low Vit D levels in plasma but not to low active Vit D levels during disease related inflammation In these conditions, plasma levels of Vit D are therefore not a valid reflection of Vit D status. Reversed causality is described as a possible factor interfering with the correct assessment of the Vit D status. It is concluded that further widespread fortification of foods and stimulation of supplement use should be reconsidered.

Improving nutritional status assessment in patients with chronic pancreatitis.

INTRODUCTION: Chronic pancreatitis (CP) is a progressive inflammatory disorder causing irreversible destruction of pancreatic tissue, leading to malnutrition. A previous study has found that currently used screening methods (periodic recording of body weight and faecal and serological markers) fall short in identifying and curbing malnutrition. Moreover, data is lacking regarding change in nutritional status over time. The aim of our study is to investigate changes in nutritional status in CP patients over time and to determine whether a more extensive set of measurements would be beneficial for nutritional screening of these patients. METHODS: CP patients who had undergone a nutritional assessment in 2012 were recruited to undergo a second assessment. The assessment consisted of anthropometric measurements, bioelectrical impedance analysis (BIA), handgrip strength (HGS), the Mini Nutritional Assessment (MNA), determination of faecal and serological markers and the Short Form Health (SF-36) questionnaire. These two assessments were compared and correlations between the various measures were calculated. RESULTS: Twenty-eight patients underwent a second assessment. An increase in fat mass and a decrease in both fat free mass (FFM) and HGS were observed. The number of patients scoring under the 10th percentile for FFM (43%-54%) and HGS in their dominant side (38%-46%) increased. FFM and HGS were positively correlated (R = 0.57). CONCLUSION: Even though current guidelines for CP follow-up were adhered to, there was a general deterioration in nutritional status. HGS correlated with FFM. HGS might be useful as a screening instrument for malnutrition in CP patients.

Bioelectrical impedance analysis to estimate body composition in surgical and oncological patients: a systematic review.

OBJECTIVE: Bioelectrical impedance analysis (BIA) is a commonly used method for the evaluation of body composition. However, BIA estimations are subject to uncertainties.The aim of this systematic review was to explore the variability of empirical prediction equations used in BIA estimations and to evaluate the validity of BIA estimations in adult surgical and oncological patients. SUBJECTS: Studies developing new empirical prediction equations and studies evaluating the validity of BIA estimations compared with a reference method were included. Only studies using BIA devices measuring the entire body were included. Studies that included patients with altered body composition or a disturbed fluid balance and studies written in languages other than English were excluded.To illustrate variability between equations, fixed normal reference values of resistance values were entered into the existing empirical prediction equations of the included studies and the results were plotted in figures. The validity was expressed by the difference in means between BIA estimates and the reference method, and relative difference in %. RESULTS: Substantial variability between equations for groups (including men and women) was found for total body water (TBW) and fat free mass (FFM). The gender-specific existing general equations assume less variability for TBW and FFM. BIA mainly underestimated TBW (range relative difference -18.8% to +7.2%) and FFM (range relative differences -15.2% to +3.8%). Estimates of the fat mass (FM) demonstrated large variability (range relative difference -15.7 to +43.1%). CONCLUSIONS: Application of equations validated in healthy subjects to predict body composition performs less well in oncologic and surgical patients. We suggest that BIA estimations, irrespective of the device, can only be useful when performed longitudinally and under the same standard conditions.

Nutritional status in patients with chronic pancreatitis.

OBJECTIVE: Chronic pancreatitis (CP) patients have an increased risk of malnutrition. Information about nutritional status of CP outpatients is scarce, and simple, sensitive methods to identify patients at risk are lacking. This explorative cross-sectional study was performed to survey the nutritional status of CP outpatients. SUBJECTS: Fifty patients with chronic or recurrent acute pancreatitis (RAP) had a nutritional assessment performed. Scores on nutritional screening tools and a quality of life questionnaire were assessed. General observations and relations between parameters were described. RESULTS: Thirty-nine patients had CP and eleven patients had RAP. According to the nutritional screening tools, 28-50% of the patients had a moderate or high risk of malnutrition. All domains of the Short Form Health Survey were significantly lowered in CP patients (all P0.001) compared with the Dutch norm values. A considerable number of patients scored below the 5th percentile on anthropometric measures. Mini Nutritional Assessment could not identify all patients with very low anthropometric scores. Substantial weight loss was not a sensitive indicator for functional impairment. CONCLUSION: CP outpatients are at risk of malnutrition. Currently used screening methods (for example, weight loss) are likely to be not sensitive enough to identify all patients with impaired body composition and restricted function. Therefore, some patients with objective decline in nutritional status will remain unidentified. An extended nutritional assessment is recommendable in CP patients.

Cost-effectiveness of nutritional intervention in elderly subjects after hip fracture. A randomized controlled trial.

UNLABELLED: Hip fracture patients can benefit from nutritional supplementation during their recovery. Up to now, cost-effectiveness evaluation of nutritional intervention in these patients has not been performed. Costs of nutritional intervention are relatively low as compared with medical costs. Cost-effectiveness evaluation shows that nutritional intervention is likely to be cost-effective. INTRODUCTION: Previous research on the effect of nutritional intervention on clinical outcome in hip fracture patients yielded contradictory results. Cost-effectiveness of nutritional intervention in these patients remains unknown. The aim of this study was to evaluate cost-effectiveness of nutritional intervention in elderly subjects after hip fracture from a societal perspective. METHODS: Open-label, multi-centre randomized controlled trial investigating cost-effectiveness of intensive nutritional intervention comprising regular dietetic counseling and oral nutritional supplementation for 3 months postoperatively. Patients allocated to the control group received care as usual. Costs, weight and quality of life were measured at baseline and at 3 and 6 months postoperatively. Incremental cost-effectiveness ratios (ICERs) were calculated for weight at 3 months and quality adjusted life years (QALYs) at 6 months postoperatively. RESULTS: Of 152 patients enrolled, 73 were randomized to the intervention group and 79 to the control group. Mean costs of the nutritional intervention was 613 Euro. Total costs and subcategories of costs were not significantly different between both groups. Based on bootstrapping of ICERs, the nutritional intervention was likely to be cost-effective for weight as outcome over the 3-month intervention period, regardless of nutritional status at baseline. With QALYs as outcome, the probability for the nutritional intervention being cost-effective was relatively low, except in subjects aged below 75 years. CONCLUSION: Intensive nutritional intervention in elderly hip fracture patients is likely to be cost-effective for weight but not for QALYs. Future cost-effectiveness studies should incorporate outcome measures appropriate for elderly patients, such as functional limitations and other relevant outcome parameters for elderly.

Application of subjective global assessment as a screening tool for malnutrition in surgical patients in Vietnam.

BACKGROUND AND AIMS: In most hospitals in Vietnam, clinical assessment of nutritional status has yet to become part of the routine clinical history taking and physical examination. It is the aim of this study to apply subjective global assessment (SGA) of nutritional status in surgical patients in the Mekong Delta, Vietnam, to determine the incidence of malnutrition according to SGA and to know whether there was an association between SGA class and infectious complications. METHODS: A prospective, cross-sectional study design was used. SGA of nutritional status was applied. Patients were rated as well nourished (A), moderately malnourished (B) or severely malnourished (C). Infectious complications (wound infection, intra-abdominal abscesses, anastomotic leakage) were recorded. RESULTS: Of the 438 patients assessed, 194 (44.3%) were classified as A, 126 patients (28.8%) were classified as B and 118 patients (26.9%) were classified as C. Of the 274 patients who underwent major abdominal surgery assessed, 61 patients (22.3%) were classified as A, 97 patients (35.4%) were classified as B and 116 patients (42.3%) were classified as C. Weight loss and percent weight loss, muscle wasting, loss of subcutaneous fat, functional capacity and significant gastrointestinal symptoms correlate significantly with the severity of SGA class (P<0.001). The rate of postoperative infectious complications was higher in patients classified as SGA class C (33.6%) than as class A (6%) and B (11%). CONCLUSIONS: A high rate of malnutrition was found, applying SGA of nutritional state in surgical patients in Vietnam. Malnutrition was associated with an increase in infectious complications. Special attention should be paid to weight loss, muscle wasting, loss of subcutaneous fat, functional capacity and gastrointestinal symptoms.

Bio-electrical impedance spectroscopy: alternatives for the conventional hand-to-foot measurements.

BACKGROUND AND AIMS: Bio-impedance spectroscopy (BIS) is a very attractive method for measuring body composition. The standard method measures impedance from hand to foot. However, in patients a hand or foot is not always accessible. In these cases alternative methods would be helpful. The objective of this study was to compare BIS measurements from hand to foot (HF) with foot to foot (FF) and hand to hand (HH) measurements as alternatives. Aims were firstly, to assess the relationship between resistance (R) values measured by the different methods, secondly, to study the influence of body geometry on this relationship and lastly, to assess the predictive capacity of the methods for measuring body fluid volumes. METHODS: In 53 subjects with different degrees of obesity (mean BMI = 38; SD = 9 kg/m(2)) three BIS measurements were performed from HF, HH and FF with a Xitron 4000B machine. Resistances of extracellular (Recw) and intracellular water (Ricw) were extrapolated by fitting the data to a Cole-Cole plot. Total body water (TBW) and extracellular water (ECW) were measured by deuterium and bromide dilution respectively. Intracellular water (ICW) was calculated as TBW-ECW. Anthropometric measurements, including length and circumference of limbs and trunk, were performed as measures for body geometry. RESULTS: The Recw, Ricw and R50 values of HF measurements could be accurately described as a function of the Recw, Ricw and R50 values of HH or FF measurements. The relative circumference of arms and legs and the length of the trunk influenced the relationship between R values of the three different measurements. The degree of overweight did not affect this relationship. The precision of the predictions of TBW, ECW and ICW based on R values of the HH measurements were comparable with the traditional HF measurements while the FF measurements gave slightly less accurate results. CONCLUSIONS: Under circumstances where total body BIS measurements cannot be performed, FF or HH measurements may be used as alternatives. However, for clinical use the effect of changes in fluid distribution on the accuracy of these methods needs to be studied further.

Case study of the clinical usefulness of bioelectrical impedance spectroscopy in evaluating nutritional status.

Bioelectrical impedance spectroscopy (BIS) can be a valuable tool in assessing changes in body composition. Although the validity of BIS in healthy subjects is relatively good, in patients considerably larger measurement errors have been reported. In this article the clinical usefulness of BIS in assessing nutritional status of one case study will be discussed. Interpretation of the predictions of BIS in this unstable patient was difficult. This is in agreement with the consensus that BIS does not give accurate prediction of body composition in individual patients. It is recommended that validation studies of BIS should focus on clinical aspects which can influence BIS measurements.