Is there a relationship between asthma and diabetes?

Background: There is an ongoing discussion regarding the coexistence of bronchial asthma and diabetes. The objective of the study was to assess the relationship between asthma and the diabetes course and the influence of corticosteroid therapy in asthma on diabetes control. Methods: This was a cross-sectional study. There were 2431 adult patients who were selected from 40,015 patients and assigned to subgroups of patients with only asthma, with both asthma and diabetes and with only diabetes. The following parameters were measured: fasting blood glucose level, oral glucose tolerance and glycated hemoglobin (HbA1c). Results: The value of HbA1c in patients with asthma and diabetes was compared to the value of this parameter in patients suffering only from diabetes: 7.23 +/- 1.73% versus 7.42 +/- 2.09% (P > 0.05). The diabetes control criteria were met in 48.5% patients with asthma and concomitant diabetes and in 50.6% patients who suffered only from diabetes. There was a negative relationship between severe asthma and diabetes control. A daily dose of budesonide up to 825 mcg used by asthmatic and diabetic patients had no significant influence on fasting glucose. Conclusions: The effect of asthma on diabetes does not seem to be significant, except for in patients with severe asthma. Inhaled steroids administered in low or mild doses do not affect fasting glycemia.