Understanding the role of co-morbidities in interstitial lung diseases

Patients with interstitial lung diseases have a higher prevalence of both pulmonary and extra-pulmonary co-morbidities compared to age- and gender-matched controls. These include respiratory failure, pulmonary hypertension (PH), coronary artery disease (CAD), gastro-oesophageal reflux disease (GERD), pneumothorax, lung cancer and obstructive sleep apnoea. Patients will frequently have multiple co-morbidities. While a unifying basis for the increased prevalence of co-morbidities in patients with interstitial lung disease (ILD) remains unknown, potential causes include up-regulation of disease mediators in the lung, telomere shortening as noted in patients with idiopathic pulmonary fibrosis (IPF), which may increase the risk for age-related diseases and cigarette smoking, which is common to a number of the known co-morbidities (1-3). While most of the literature pertaining to complications emanates from investigations of IPF, these maladies may occur in many other forms of ILD. An awareness of the propensity, impact and management of these complications is important in the holistic care of patients with various forms of ILD.