title: Association of air-conditioning with respiratory symptoms in office workers in tropical climate.
abstract: To evaluate the association of heating, ventilation and air-conditioning systems (HVAC) and respiratory symptoms in a tropical city, self-administered questionnaires were given to 2000 individuals working in air-conditioned office buildings and to 500 control workers in naturally ventilated buildings. Reported symptoms from the two populations were analyzed using chi-square tests, univariate and multiple logistic regressions models. Symptoms were the outcome variable and the odds ratios were adjusted by gender, age, accumulated work time, smoking habits and atopic background. There was a 79.8% response rate and there was a positive association of nasal symptoms (odds ratio, OR = 1.59, 95% confidence interval, CI = 1.11-2.28), naso-ocular symptoms (OR = 1.58, 95% CI = 1.05-2.38), persistent cough (OR = 3.04, 95% CI = 2.00-4.63) sinusitis symptoms (OR = 1.85, 95% CI = 1.27-2.71) and building-related worsening of the symptoms (OR = 4.92, 95% CI = 2.93-8.27) with working in air-conditioned buildings. In conclusion, our study suggests that artificial air-conditioning is a matter of concern for respiratory symptoms in cities with hot and humid climate.
  
  
  CONCLUSIONS
  This study suggests that indoor air-related respiratory symptoms are a matter of concern in places with hot and humid climate. The regression models were adjusted by confounders that could be used in further reanalysis of indoor air quality related symptoms and ventilation systems with expanded variety of climatic conditions.
authors.affiliation: Division of Allergy and Clinical Immunology, Internal Medicine Department, School of Medicine, Millennium Institute, University of São Paulo, São Paulo, Brazil. gustavog@usp.br
authors.forename: G S
authors.initials: GS
authors.lastname: Graudenz
authors.forename: C H
authors.initials: CH
authors.lastname: Oliveira
authors.forename: A
authors.initials: A
authors.lastname: Tribess
authors.forename: C
authors.initials: C
authors.lastname: Mendes
authors.forename: M R D O
authors.initials: MR
authors.lastname: Latorre
authors.forename: J
authors.initials: J
authors.lastname: Kalil
mesh_terms: D000328:Adult; D000367:Age Factors; D000389:Air Conditioning / Q000009:adverse effects*; D001938:Brazil; D016022:Case-Control Studies; D003371:Cough / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D016017:Odds Ratio; D012140:Respiratory Tract Diseases / Q000209:etiology*; D012737:Sex Factors; D014329:Tropical Climate; D014505:Urban Population