Clinical laboratory measures in relation to depression, disability, and cognitive impairment in elderly patients

To characterize the dimensions of physiological abnormalities that commonly occur in older individuals in a residential care setting and to evaluate their association with clinical measures, the authors conducted an exploratory factor analysis on clinical laboratory measures from a sample of 231 elderly residents (mean age: 86) living in a nursing home and congregate apartment facility. An eight-factor solution accounted for 70.2% of the variance in these measures; factors identified were interpreted as indices of renal function, protein/calorie/nutritional status, serum electrolytes/osmolarity, liver function, acute-phase processes, plasma lipids, acid/base status, and renal-tubular function. The nutritional factor was significantly associated with measures of disability and the presence of depression. The acute-phase processes factor was significantly associated with cognitive impairment.