The use of inhaled anticholinergics may increase the risk of community-acquired pneumonia (CAP) in patients with bronchial asthma - this is indicated by the results of a case-control study conducted in Spain, published in the European Respiratory Journal.

The aim of this study was to determine whether the use of inhaled drugs is a risk factor for the development of community-acquired pneumonia.

All cases of confirmed PV occurring within one year in patients with chronic bronchitis, chronic obstructive pulmonary disease (COPD) or bronchial asthma were included in the analysis. The risk factors for the development of the CAP and the inhalation drugs received were recorded during a personal survey of the patients. For the period from 1999 to 2000, 1336 cases of PAC were identified and a comparison was made with 1326 controls comparable in terms of sex, age and place of treatment. In the EP group, 35% of patients had chronic bronchitis, COPD or bronchial asthma, compared to 18% of patients in the control group.

Among COPD patients, 49% in the pneumonia group and 24% in the control group used inhaled glucocorticoids regularly in the past year.

The effect of inhaled drugs on the risk of developing PV has been observed in patients with COPD and bronchial asthma. In patients with COPD, inhaling glucocorticoids increased the risk of developing PE by 3.26 times (1.07–9.98, p = 0.038). Smoking also significantly increased the risk of developing pneumonia (risk ratio 4.23). In patients with bronchial asthma using inhaled anticholinergics (especially ipratropium bromide), the risk ratio was 8.8 (1.02-75.7, p = 0.048).

The effect of anticholinergics on the onset of PV can be explained by a decrease in the ciliary activity of the ciliated epithelium of the bronchi and a decrease in the secretion of mucus, which promotes the growth of pathogens.

In patients with chronic bronchitis, no association has been found between the use of any inhaled medication and the risk of PV. Inhalation of β2-adrenergic agonists had no significant effect on the risk of PV in any of the nosological forms studied.

The use of the pneumococcal vaccine had a pronounced protective effect (risk ratio of 0.35).

Thus, the inhalation use of glucocorticoids in patients with COPD and anticholinergics in patients with bronchial asthma may contribute to the onset of CAP. At the same time, it is difficult to differentiate the effect of inhalation therapy on the risk of PV from the effect of the severity of chronic diseases (COPD or asthma) on the occurrence of this infectious pathology.