FEV1, FVC, FEV1 /FVVC as predictors of rhinitis among saw mill workers in north central Nigeria.

Background: Rhinitis is one of the commonest occupational related respiratory disorders that is only restricted to the upper airway but can involve the lower respiratory tract with considerable airflow limitation, this study was conducted assess the ventilator function of persons exposed to saw dust with rhinitis symptoms.

Methods: This is a cross sectional study carried out among 200 randomly selected saw mill workers and 200 healthy staff of Jos University Teaching Hospital staff in Jos metropolis from September to November 2008. Data on sociodemographic variables, symptoms of rhinitis, etc was obtained using a modified semi structured British medical research council questionnaire while respiratory function data was measured using a spirometry.

Result: A total of 400 responds comprising of 200 saw mill workers and 200 controls participated in this study. Based on diagnostic criteria. 43% of the subjects fit into diagnosis of rhinitis, 33% had asthma symptoms and 24 % did not fit into any category compared to none of < 5% of the control group. The ventilatory function based on FEV1, FVC, FEV1/FVC ratio and PEFR showed a significant decline when matched with controls and predicted value, suggesting an airflow limitation among the rhinitis group.

Conclusion: Rhinitis associated with wood dust exposure is not restricted to airway but involves the entire respiratory tract with airflow limitation as one of its consequences.