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Background: Asthma is a common disease and a major public health concern. Respiratory symptoms are related to its prognosis, which in turn associates with lung function. Still this association on a long-term basis is not entirely understood.

Aim: To study the association of the type and number of respiratory symptoms with FEV 1 and FEV 1 decline in women and men with asthma.

Method: A population-based cohort of adults with asthma was examined at study entry between 1986 and 2001 and at follow-up between 2012 and 2014, and n=977 had valid measurements of FEV 1 on both occasions. Data regarding respiratory symptoms at study entry (recurrent wheeze, dyspnoea, longstanding cough and productive cough) were analysed in relation to FEV 1 and annual decline in FEV 1, both unadjusted and adjusted for other potentially associated factors by linear regression.

Results: For both sexes recurrent wheeze and dyspnoea were associated with lower FEV 1 at study entry and follow-up, while productive cough was associated with lower FEV 1 only at follow-up. No associations were found between the type of symptoms and annual decline in FEV 1. In adjusted analyses, the association between recurrent wheeze and lower FEV 1 both at study entry and follow-up remained significant among women. Also, the association between a higher number of symptoms with lower FEV 1 both at study entry and follow-up were present for both sexes and remained after adjustment.

Conclusions: Particularly recurrent wheeze and a higher number of respiratory symptoms may predict lower lung function also in the long run among women and men with asthma.