A study of comorbidity in patients with chronic obstructive pulmonary disease

AIMS: The impact of the chronic obstructive pulmonary disease (COPD) severity on the number of exacerbations, and the interdependence of COPD and some concomitant diseases were studied in chronic pulmonary patients. In order to determine the actual influence of some risk factors and comorbidity on the course of COPD, we conducted a study in two family medicine consulting offices, one in the city of Split and the other on the island of Brac. METHODS: This retrospective study included a sample of 64 subjects, mean age 64.43 years, divided into two groups of 32 subjects each (group 1 and group 2). After taking history data and clinical examination, spirometry was performed. The severity of COPD was determined on the basis of lung function tests. RESULTS: There were 15 (46.9%) smokers in group 1, seven of them former smokers, and 20 (65.6%) smokers in group 2, eight of them former smokers. The groups differed significantly according to the mean number of annual exacerbations (1.3 in group 1 and 2.4 in group 2; p < 0.001). The frequency of exacerbations was higher in smokers and depended on the stage of COPD. If COPD was more severe, the exacerbations were more frequent and influenced the progression of irreversible functional changes on the lungs. Productive cough was more frequent in smokers. The correlation of concomitant diseases and degree of COPD was found in group 2 (hypertension, r = 0.305; p = 0.014). In group 1, there was correlation between patient age and concomitant disease (cardiac arrhythmias, r = 0.307; p = 0.013), whereas in group 2 it was significant in case of hypertension (r = 0.474; p < 0.001) and cardiomyopathy (r = 0.301; p = 0.016). DISCUSSION: Cigarette smoke causes chronic inflammatory changes in the lungs. In our study, the number of patients suffering from persistent cough accompanied by sputum was higher in group 2, which also comprised of more smokers, but differences between smokers and non-smokers according to this characteristic were not statistically significant. Study groups differed significantly according to the number of COPD exacerbations per year (with more exacerbations in the group with more smokers). In group 2, there was a correlation between COPD severity and hypertension. CONCLUSIONS: Comorbidity of COPD and cardiovascular diseases was confirmed, along with correlation between age and cardiovascular complications in patients with COPD.