A comparison between erythrocyte sedimentation rate (ESR) and selected acute-phase proteins in the elderly

The erythrocyte sedimentation rate (ESR) and selected acute-phase proteins (APPs) were studied in 101 elderly people (mean age, 72 years) to determine their utility as diagnostic aids in subjects with underlying infections or inflammation. ESR and values for serum immunoglobulin A (IgA), the fourth component of complement (C4), haptoglobin, and alpha-1-antitrypsin (AAT) all correlated with infection or inflammation. C4 was the only test predictive of mortality at six months. Neither ESR nor any of the APPs demonstrated concomitantly high sensitivity, specificity, and positive predictive values. Receiver-operating characteristic curve analysis revealed low true positive to false positive ratios for all of the tests studied. In the elderly, measurement of APPs as a guide to underlying infection or inflammation has limited utility and offers no advantage over the traditional low-cost ESR.