Influence of socioeconomic status on community-acquired pneumonia outcomes in elderly patients requiring hospitalization: a multicenter observational study.
BACKGROUND
The associations between socioeconomic status and community-acquired pneumonia outcomes in adults have been studied although studies did not always document a relationship.The aim of this multicenter observational study was to determine the association between socioeconomic status and community-acquired pneumonia outcomes in the elderly, in the context of a public health system providing universal free care to the whole population.


METHODS
A total of 651 patients aged > or =65 years hospitalized due to community-acquired pneumonia through the emergency departments of five Spanish public hospitals were recruited and followed up between May 2005 and January 2007. The primary outcomes studied were: length of stay, intensive care unit admission, overall mortality and readmission. Socioeconomic status was measured using both individual and community data: occupation [categorized in six social groups (I, II, III, IVa, IVb and V)], educational level (< or = primary level or > or = secondary level) and disposable family income of the municipality or district of residence [>12,500 euro (high municipality family income) and < or =12,500 euro (low municipality family income)]. The six social groups were further categorized as upper/middle social class (groups I-IVb) and lower class (group V).Bivariate and multivariate analyses were performed. OR and their 95% confidence intervals were calculated. All statistical tests were two tailed and statistical significance was established as p < 0.05.


RESULTS
17.7% of patients lived in a municipality or district with a high municipality family income and 63.6% were upper/middle social class (I-IVb). Only 15.7% of patients had a secondary education. The adjusted analysis showed no association between pneumonia outcomes and social class, educational level or municipality family income. However, length of stay increased significantly in patients in whom the factors, living alone and being a smoker or ex-smoker coincided (p < 0.001).


CONCLUSIONS
We measured socioeconomic status using both individual and community data and found no association between social class, educational level or municipality family income and the variables of pneumonia outcomes. The lack of differences between social classes supports the provision of universal, equitable health care by the public health system.
Izquierdo
Conchita
C
Department of Health, Generalitat of Catalonia, Roc Boronat 81-95, 08005 Barcelona, Spain. conchita.izquierdo@gencat.cat
Oviedo
Manuel
M
Ruiz
Laura
L
Sintes
Xavier
X
Vera
Isabel
I
Nebot
Manel
M
Bayas
Jose-María
JM
Carratalà
Jordi
J
Varona
Wenceslao
W
Sousa
Dolores
D
Celorrio
Jose-Miguel
JM
Salleras
Luis
L
Domínguez
Angela
A
D000368:Aged; D000369:Aged, 80 and over; D017714:Community-Acquired Infections / Q000628:therapy*; D004522:Educational Status; D005260:Female; D006299:Health Services for the Aged / Q000191:economics / Q000592:standards*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006779:Hospitals, Public; D006801:Humans; D007182:Income / Q000145:classification; D007902:Length of Stay; D008297:Male; D009790:Occupations / Q000145:classification; D011014:Pneumonia / Q000175:diagnosis / Q000382:microbiology / Q000628:therapy*; D036301:Qualitative Research; D012923:Social Class; D012959:Socioeconomic Factors; D013030:Spain; D016896:Treatment Outcome