Journal of Gerontology: MEDICAL SCIENCES © The Author 2011. Published by Oxford University Press on behalf of The Gerontological Society of America. Cite journal as: J Gerontol A Biol Sci Med Sci. 2011 December;66A(12):1393–1394 All rights reserved. For permissions, please e-mail: journals.permissions@oup.com. doi:10.1093/gerona/glr163 Advance Access published on September 7, 2011 1393 Dear Sir, We have read with interest the systematic review article of Diederichs and colleagues (1), referring to the existing multimorbidity indexes. We fully agree with the authors in their opinions that clear and comprehensive criteria for the selection of chronic conditions, which qualify for multi- morbidity, are still lacking. Accordingly, there is no agree- ment on the number and type of diseases to be included in multimorbidity indices, so these lack homogeneity, as well as external reproducibility in the case of prognostic multi- morbidity tools. For this reason, most clinicians and inves- tigators, usually, continue to use the Charlson–Deyo index as the gold-standard tool when referring to prognosis in patients with multiple chronic diseases (PMCD) (2,3). Nevertheless, the Charlson–Deyo index has been around for over 20 years; during this time, new diagnostic–therapeutic options have drastically changed the course of many of the included conditions (2,4). Recently, the new notion of polypathological patient (PP) has been introduced in the management of these popula- tions (5,6). This definition arose from the needs of clini- cians to integrally approach the medical problems of patients with multiple diseases. In these patients, it is difficult to establish the protagonism of any of the comorbidities because of their similar complexity, their similar potential to become unstable, and their mutual relationships. A PMCD is considered a PP when suffering from chronic dis- eases from two or more of eight predefined categories; these categories were established by a panel of experts using cri- teria of end effect on function of key organs (independently of the primary disease), frequent chronic conditions with high mortality and/or potential of becoming unstable, or frequent comorbidities when mental and/or functional impairment thresholds were definitively reached (4–7). Therefore, the PP notion is globally centered on the patient and not on any “protagonist” disease nor on any professional health care worker who attends a PMCD. An increasing number of studies are determining that this emergent population is rea- sonably homogeneous, highly complex, clinically vulnera- ble, functionally impaired, dependent on caregivers, and socially fragile (7). Additionally, the Polypathological Patient and Advanced Age Study Group, of the Spanish Society of Internal Med- icine, has recently developed and validated a 1-year mor- tality predictive index on PP, by means of a multicenter prospective cohort-study recruiting 1,632 PP after hospi- tal discharge, outpatient clinics, or home hospitalization, from 33 hospitals (8). The PROFUND index includes nine easy-to-achieve variables: one demographical (age ≥ 85 years, 3 points), four clinical (presence of active neoplasia, 6 points; dementia, 3 points; disabling dyspnea by means of III–IV functional class on New York Heart Association and/or Medical Research Council, 3 points; delirium dur- ing last hospital admission, 3 points), one laboratory (hemoglobinemia < 10 g/dL, 3 points), one functional (Barthel index < 60 points, 4 points), one sociofamilial (caregiver other than spouse or no caregiver; 2 points), and one care (number of hospital admissions in last 12 months ≥4, 3 points) variable. Mortality in the derivation/validation cohorts is detailed in Tables 1 and 2. Calibration was good in derivation/validation cohorts, and discrimination power by area under the curve was 0.77/0.7, respectively. When comparing the PROFUND index with the Charlson–Deyo index, this last showed a good calibration but a lower discrimination power (area under the curve, 0.59). We think, that this new notion of PP is in the way of solv- ing this heterogeneity, because it comprises the 11 diagnosis cited by the authors, points toward advanced-age populations (mean age of PP in different studies ranged 74–78 years), and reflects an homogeneous, emergent (in-hospital preva- lence of PP ranges 24%–40%), and high-risk population Letter to the Editor A NEW PROGNOSTIC INDEX CENTERED ON POLYPATHOLOGICAL PATIENTS. THE PROFUND INDEX Maximo Bernabeu-Wittel, 1 Francesc Formiga, 2 and Manuel Ollero-Baturone 1 ; on behalf of the PROFUND RESEARCHERS 1 Department of Internal Medicine, Hospital Universitario Virgen del Rocío, Seville, Spain. 2 Department of Internal Medicine, Hospital Universitari de Bellvitge, Barcelona, Spain. Address correspondence to Máximo Bernabeu-Wittel, Ph.D., M.D, Department of Internal Medicine, Hospitales Universitarios Virgen del Rocío, Avda. Manuel Siurot, s/n. 41013 Sevilla, Spain. Email: maxbw@telefonica.net Received March 7, 2011; Accepted June 9, 2011 Decision Editor: Luigi Ferrucci, MD, PhD Downloaded from https://academic.oup.com/biomedgerontology/article-abstract/66A/12/1393/628636 by guest on 08 June 2020