[Incidence, air pollution and risk factors of acute otitis media in the first year of life: a prospective study].
BACKGROUND
Epidemiological studies of acute otitis media (AOM) are scarce and no prospective studies have been performed in Spain.


OBJECTIVE
To describe the incidence of AOM in the first year of life and its associated risk factors, with special focus on air pollution.


METHODS
We performed a prospective cohort study of 229 newborn infants during the first year of life stratified by pollution zones, and followed-up by their pediatricians in their health center. AOM was defined on clinical grounds. A questionnaire on risk/protective factors included items on the following: sex, older siblings, smoking, breastfeeding, socioeconomic status, parental education and the mother's occupational status.


RESULTS
The incidence of AOM episodes during the first year of life was 45 % and the proportion of children who experienced at least one episode was 32 %. Independent risk factors were male gender (aOR: 2.03; 95 % CI: 1.09-3.7) and living in a polluted area (aOR: 2.01; 95 % CI: 1.05-3.84). Independent protective factors were being born in spring (aOR: 0.41; 95 % CI: 0.19-0.88) and having a mother with at least primary school education (aOR: 0,53; 95 % CI: 0.24-1.15). Socioeconomic markers indicated a lower mean level among families whose children had at least one AOM episode.


CONCLUSIONS
Air pollution and low socioeconomic status are greater risk factors for AOM than having siblings or parents who smoke. A minimum educational level reduces the risk of AOM. The incidence of AOM could be reduced by modifying certain environmental factors.
Cáceres Udina
Ma J
MJ
Centros de Salud Mazarrón, Spain.
Alvarez Martínez
J A
JA
Argente del Castillo
J
J
Chumilla Valderas
Ma A
MA
Fernández Alvarez
E
E
Garrido Romera
A
A
Sánchez Gascón
F
F
García-Marcos
L
L
D000208:Acute Disease; D000397:Air Pollution / Q000009:adverse effects; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010033:Otitis Media / Q000453:epidemiology* / Q000209:etiology; D011446:Prospective Studies; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology