Indoor air quality and the risk of lower respiratory tract infections in young Canadian Inuit children.
BACKGROUND
Inuit infants have the highest reported rate of hospital admissions because of lower respiratory tract infections in the world. We evaluated the prevalence of reduced ventilation in houses in Nunavut, Canada, and whether this was associated with an increased risk of these infections among young Inuit children.


METHODS
We measured ventilation in 49 homes of Inuit children less than 5 years of age in Qikiqtaaluk (Baffin) Region, Nunavut. We identified the occurrence of lower respiratory tract infections using a standardized questionnaire. Associations between ventilation measures and lower respiratory tract infection were evaluated using multiple logistic regression models.


RESULTS
The mean number of occupants per house was 6.1 people. The mean ventilation rate per person was 5.6 L/s (standard deviation [SD] 3.7); 80% (37/46) of the houses had ventilation rates below the recommended rate of 7.5 L/s per person. The mean indoor carbon dioxide (CO2) concentration of 1358 (SD 531) ppm was higher than the recommended target level of 1000 ppm. Smokers were present in 46 homes (94%). Of the 49 children, 27 (55%) had a reported history of lower respiratory tract infection. Reported respiratory infection was significantly associated with mean CO2 levels (odds ratio [OR] 2.85 per 500-ppm increase in mean indoor CO2, 95% confidence interval [CI] 1.23-6.59) and occupancy (OR 1.81 for each additional occupant, 95% CI 1.14-2.86).


CONCLUSIONS
Reduced ventilation and crowding may contribute to the observed excess of lower respiratory tract infection among young Inuit children. The benefits of measures to reduce indoor smoking and occupancy rates and to increase ventilation should be studied.
Kovesi
Thomas
T
Department of Paediatrics, Children's Hospital of Eastern Ontario, Ottawa, Ont. kovesi@cheo.on.ca
Gilbert
Nicolas L
NL
Stocco
Corinne
C
Fugler
Don
D
Dales
Robert E
RE
Guay
Mireille
M
Miller
J David
JD
D017677:Age Distribution; D016902:Air Pollution, Indoor / Q000009:adverse effects* / Q000032:analysis; D000704:Analysis of Variance; D002170:Canada / Q000453:epidemiology; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004784:Environmental Monitoring; D062665:Epidemiological Monitoring; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization / Q000706:statistics & numerical data; D006798:Housing / Q000639:trends; D006801:Humans; D015994:Incidence; D007223:Infant; D004930:Inuit / Q000706:statistics & numerical data*; D016015:Logistic Models; D008297:Male; D008452:Maximum Allowable Concentration; D011336:Probability; D012008:Recurrence; D012141:Respiratory Tract Infections / Q000453:epidemiology* / Q000209:etiology* / Q000503:physiopathology; D012720:Severity of Illness Index; D017678:Sex Distribution; D011795:Surveys and Questionnaires; D014691:Ventilation / Q000592:standards