Annual incidence and risk factors for nosocomial bacterial infections in an acute care geriatric unit.

Purpose. - Elderly inpatients are particularly exposed to the risk of nosoc omial infections, thus the study of their risk factors and consequences is of interest. Methods. - Among 1,565 subjects referred to a short-term geriatric unit, pa tients hospitalised for a year for an acute event and unable to move themse lves were followed up for the occurrence of nosocomial infections. Results. - Among these 402 immobilised patients (age: 86.3 +/- 7.6 years), 102 nosocomial infections occurred in 91 patients (22.6%), whereas the esti mation of the incidence in the total hospitalised population (1,565 subject s, age: 85.1 +/- 6.2 years) was 9.4% (95% confidence interval[CI] 8.3-11.2) . Forty-seven point seven percent of nosocomial infections were urinary tra ct nosocomial infections, 27.5% were lower respiratory nosocomial infection s, 9.2% were cutaneous nosocomial infections, 7.3% were septicaemia and 8.2 % were of unknown origin. The relative risk (RR) of NI linked to functional dependency for mobility was 5.5 (95% Cl: 3.93-7.7, P < 0.001). Other risk factors were: for all nosocomial infections: cancer diagnosis (RR 1.1, 95% Cl: 1.1-1.2, P = 0.01); and respectively for urinary tract NI: bladder indw elling (RR 4.8, 95% Cl: 2.9-7.7, P < 0.001), pulmonary NI: swallowing disor ders (RR 5.4, 95% CI:2.8-10.5, P < 0.001); and septicaemia: venous catheter (RR 5.4, 95% Cl: 1.3-23.3, P = 0.002). NI were associated with an increase d length of stay (22.1 +/- 11.7 days in infected patients vs 16.3 9.5 days in immobilised non-infected subjects, P < 0.001). The mean length of stay f or the 1,565 subjects was 10.3 +/- 7.6 days. Death was attributed to nosoco mial infections in 13 subjects. In conclusion, functional dependency for mo bility bladder indwelling, venous catheter, swallowing disorders and diagno sis of cancer were risk factors for nosocomial infections in hospitalised e lderly subjects in an acute-care setting. (C) 2001 Editions scientifiques e t medicales Elsevier SAS.