Incidence and clinical features of patients with comorbidity attended in internal medicine areas

BACKGROUND AND OBJECTIVE: Our objective was to assess the incidence and clinical features of patients with numerous disorders-comorbidity patients (CP)-and to clinically validate the CP criteria defined by a panel of experts (patients with 2 or more chronic diseases, distributed into seven cathegories). PATIENTS AND METHOD: Prospective observational study of all patients, attended in internal medicine areas of a tertiary teaching hospital, during June 2003. Patients were stratified in 3 cohorts: CP, palliative, and general (GE). Incidence of CP, functional evaluation (at baseline at; admission, and at discharge), and burden of hospital care (by means of urgent and programmed visits, as well as episodes of hospitalization) in the last 12 months were analyzed. A multivariate analysis of predictors of survival and functional deterioration (fall in Barthel's scale 10 points between baseline-discharge values) was performed in the CP cohort. RESULTS: 339 patients (CP cohort: 132; palliative: 52; GE: 155) were included. The overall incidence was 38.9/100 admissions/month. CP were older (75 [11] vs 67 [16]); had higher mortality (19.3% vs 6.1%; relative risk [RR]: 3.66 [95% confidence interval [CI], 1.65-8.131; lower functional ability at baseline (45 vs 95), at admission (20 vs 75), and at discharge (20 vs 95); higher rates of significant functional deterioration (16% vs 7%; RR = 2.47 [95% Cl, 1.15-5-35]); and required more burden of hospital care by means of urgent care (3-6 [3.4] episodes vs 2.4 [1.9]), and hospitalizations (1.9 [1.3] vs 1.5 [1]) than GE patients. Chronic digestive/hepatic diseases (odds ratio [OR] = 48.3 [2.4-980.9], peripheric vascular disease/diabetes with visceral involvement (OR = 5.6 [CI 95%, 1.1-28.6]), and better functional ability at admission were associated with survival. Female gender (OR) 46.6 [CI 95%, 4.5-486.9]), chronic lung disease (OR = 8.9 [CI 95%, 1.2-64]), and neurologic disease with disability (OR = 8 [CI 95%, 1.1-58.9]), were associated with significant functional deterioration during hospital stay. CONCLUSIONS: The defined CP criteria were highly accurate in detecting a population of patients with high attention in Internal Medicine areas, high mortality rates, clinical frailty (more need of hospital care), and significant functional deterioration. Barthel's scale identified correctly this group of patients, and was independently associated with survival.