Diabetes as a risk factor for severe exacerbation and death in patients with COPD: a prospective cohort study

Background Type 2 diabetes comorbidity is common in patients with COPD. One of the most frequent causes of hospital admission in patients with COPD are exacerbations. Methods Prospective cohort study, which included 512 patients with COPD recruited in a primary care centre in Mollerussa (Lleida, Spain). Inclusion criteria were: patients >40 years of age with COPD according to the Global Initiative for Chronic Obstructive Lung Disease. Variables collected were as follows: age, gender, civil status, education level, smoking habit, severity (Global Initiative for Chronic Obstructive Lung Disease), comorbidities (Charlson), history of severe exacerbations, dyspnoea (mMRC), BODEx, EuroQol 5 D and depression (HAD). Logistic regression was used to determine the association of diabetes with risk of hospital admission and death. Results Prevalence of diabetes was 25.8%. During the second year of follow up, 18.2% of patients with COPD and diabetes were admitted for exacerbation, in comparison with 8.9% non-diabetic COPD patients. The variables associated with hospital admission were diabetes (ORa=1.54); gender (men, ORa=1.93); age (ORa=1.02); number of hospital admissions during the previous year: 1 (ORa=2.83) or more than one admission (ORa=4.08); EuroQol 5 D (ORa=0.76) and BODEx (ORa=1.24). With the exclusion of BODEx, all these variables were associated with a higher risk of death. Conclusion Prevalence of diabetes is high in patients suffering from COPD. COPD patients with diabetes are at higher risk of severe exacerbation and death. The suggested predictive model could identify patients at higher risk so that adequate preventive and therapeutic measures can be implemented.