The prevalence of lung function abnormalities appears to be higher in smoking patients with ischemic heart disease (IHD) than within the general adult population. However, the prevalence of lung function abnormalities in these patients has been poorly investigated. The aim of this study was to investigate the prevalence of lung function abnormalities in smoking patients with IHD.

This cross-sectional study conducted in FSI hospital in Tunisia included smoking patients (≥10pack-year) with suspected CAD. Pre and post-bronchodilator spirometry was performed according to international standards. Airflow limitation (AL) and restrictive lung function (RLF) are diagnosed according to international guidelines.

Spirometry was undertaken for 122men with mean age of 59.3±9.5years and mean pack-year of 52.3±28.3. Mean CAD follow-up duration was 3.9±4.5years. Spirometry was normal in 63.9% of cases. AL was observed in 20.5% of patients: 5.7% had mild AL, 12.3% had moderate AL, 1.6% had severe AL and 0.8% had very severe AL. Most patients with AL (72%) had no previous spirometry testing or diagnosed pulmonary disease. Chronic obstructive pulmonary disease was the etiology of AL in 96% of patients. RLF was observed in 7.4% of patients and small airway disease in 8.2%. Obesity was the etiology of RLF. AL was associated with greater respiratory symptomatology, chest-X-ray abnormality and pulmonary arterial hypertension (P<0.05).

Airflow limitation compatible with chronic obstructive pulmonary disease affects almost a fifth of patients with ischemic heart disease. While airflow limitation is associated with additional morbidity, it is largely undiagnosed and untreated.