Impact of comorbidities on baseline characteristics in severe asthmatics in the German Asthma Net (GAN)

Assessing comorbidities is crucial for diagnosing and managing severe asthma, yet its impact on asthma outcomes is unclear. We studied the prevalence and effect of baseline comorbidities in 2572 adults from the German severe asthma registry regarding asthma control, exacerbations, hospitalizations and lung function with Chi-Squared or Fisher's Exact Test, Kruskal-Wallis or Wilcoxon rank-sum test or Pearson's or Spearman's correlation coefficients. Our population (mean age 53,68±13,23, 42,2% males, ACT score 14,4±5,5, FEV1 2±0,81l) had mean number of comorbidities 4,2±2 (54,2% had 1-4, 43,6% had ≥5) as (≥5%): allergic conditions(AC) 62,3%, frequent respiratory infections(RI) 60,4%, OCS-related conditions(OCS-C) 50%, chronic sinusitis(CS) 48%, arterial hypertension(HT) 34,5%, reflux disease (GERD) 33,7%,obesity-29,4%, nasal polyps(NP) 25,5%, ASS intolerance-21,2%, depression-15%, COPD-8,3%, cardiovascular disease(CVD)7,5% and urticaria 5,4%. Exacerbations were linked to OCS-C, RI(<italic>p</italic><0.001), GERD(<italic>p</italic>=0.002), EGPA(<italic>p</italic>=0.02), depression(<italic>p</italic>=0.01), hyperventilation(<italic>p</italic>=0.003) and HT(<italic>p</italic>=0.04). Lower ACQ-5 was associated with eczema(<italic>p</italic>=0.04), OCS-C, RI, GERD, depression, obesity, NP, EGPA and HT(all <italic>p</italic><0.001), CS(<italic>p</italic>=0.02) and COPD(<italic>p</italic>=0.001). Reduced FEV1 correlated with OCS-C, COPD, HT(<italic>p</italic><0.001) and pulmonary hypertension(<italic>p</italic>=0.002). Hospitalization risk was linked to OCS-C, RI, depression, CVD(<italic>p</italic><0.001), COPD(<italic>p</italic>=0.02), ABPA(<italic>p</italic>=0.03), bronchiectasis(<italic>p</italic>=0.003), neuromuscular disease(<italic>p</italic>=0.03) and atelectasis(<italic>p</italic>=0.04). Biologic-treated patients had more AC(<italic>p</italic><0.001)and less depression/HT (<italic>p</italic>=0.01/<italic>p</italic>=0.001). Comorbidities are often linked to worse outcomes, highlighting the need for their evaluation in severe asthma.