Nutritional and hydration status in elderly subjects: clinical rating versus bioimpedance analysis

Malnutrition and dehydration are common in elderly. A simple, reliable instrument to assess nutritional and hydration status would be very helpful. Bioelectrical impedance analysis (BIA) has been promising in this context, but data of elderly persons and geriatric in-hospital patients are rare. Therefore, we first compared BIA measurements (resistance, reactance, phase angle and a resulting vectorgraph) with a clinical assessment in 31 community-dwelling women and 30 female nursing-home residents. The results of the BIA measurement correlated well to weight, hand grip strength, and calf circumference. We then compared BIA measurements with clinical judgement of hydration status in 103 acute geriatric hospital in-patients. Concordance between the results of clinical judgement and BIA measurements was only 43.7%. In assessing geriatric in-patients, there is little concordance between the clinical and the bioelectrical evaluation of the hydration status.