Glycemic Control & Morbidity in Diabetics With COPD Exacerbation. A Retrospective Study

Background: Diabetes and chronic obstructive pulmonary disease (COPD) are widely prevalent and comorbidity with these diseases is quite common. However, there is limited data on the interrelation between glycemic control and COPD exacerbations in diabetic patients. Objective: To study the association between pre-admission glycemic control and COPD clinical outcomes including mortality, risk of hospital readmission and the need for mechanical ventilation. Methods: A retrospective population-based cohort study. We screened for patients with both diabetes and COPD exacerbation aged 35 years and above. Pre-admission glycemic control was defined by the last HBA1C level prior to hospitalization. Patients with HBA1C>8% were defined as uncontrolled. We evaluated the difference between controlled and uncontrolled groups in the rates of mortality, readmission and the need for mechanical ventilation. We examined demographic and clinical parameters that might reflect COPD severity including: COPD medication use, blood hemoglobin, platelets, LDH and CRP levels. Results: 513 hospitalizations with diabetes and COPD were screened. 222 hospitalization were excluded either due to unestablished diagnosis of COPD or due to lack of HBA1C test in the preceding year. Of the remaining 291, 208 admissions were with controlled diabetes whereas 83 were uncontrolled. Although not statistically significant, the rate of re-hospitalization was higher in the uncontrolled group (OR 1.99, CI 0.99–4.0, p-value 0.051). There was no statistically significant difference in mortality (OR 1.6, CI 0.73–3.5, p-value 0.243). The use of oxygen and the need for noninvasive mechanical ventilation were significantly higher in the uncontrolled group (67.5% vs. 52.4%, p-value 0.019, 33.7% versus 18.8%, p-value 0.006, respectively). There was no significant difference in possible confounders tested between the groups. Conclusion: Uncontrolled diabetes may adversely affect patients with COPD exacerbation. Larger studies are needed to conclusively determine the impact of glycemic control on COPD morbidity and mortality.