Arterial ageing is characterised by degradation of elastic fibres and increased stiffness of elastic arteries. Although low lung function and arterial stiffness are strongly related to age, the association between lung function and arterial ageing has not been widely explored. We used a large population-based study of 50–64 year olds to assess the association between lung function (measured by spirometry and CO diffusing capacity (D_LCO)) and arterial stiffness (measured by carotid-femoral pulse-wave velocity (c-f PWV)).

Participants from the Swedish CArdioPulmonary bioImage Study (SCAPIS) cohort with information on spirometry (n = 8941) and D_LCO (n = 8616) were included. General linear models (lung function quartiles) and linear regression was used to determine the association between lung function and c-f PWV.

FEV₁ (L), FVC (L), D_LCO (mmol/(min kPa)) and D_LCO/V_A (mmol/(min kPa L)) were significantly and inversely associated with c-f PWV after adjustments; mean PWV (m/s) in Q1 (highest lung function) vs Q4: FEV₁; 8.45 vs 8.60, p-value 0.001; FVC; 8.45 vs 8.57, p-value 0.018; D_LCO; 8.46 vs 8.60, p-value 0.002; and D_LCO/V_A; 8.47 vs 8.58, p-value 0.001. In sex-stratified analyses, significant findings were reflected for FEV₁ and D_LCO in men only. The results remained significant for D_LCO in all never smokers and in all participants without COPD or airflow limitation on spirometry.

A reduction in spirometry and D_LCO is associated with elevated arterial stiffness in middle-aged men. A reduction in D_LCO is associated with higher c-f PWV even in never smokers and in those without COPD or airflow limitation on spirometry.