Multimorbidity prevalent in patients with IPF

In patients with idiopathic pulmonary fibrosis, multimorbidity was prevalent and comorbidity clusters may represent phenotypes with distinct profiles and characteristics, researchers reported in Respiratory Medicine.

Cardiovascular, pulmonary, endocrine and psychological diseases were frequent comorbidities,” Thomas Skovhus Prior, MD, consultant at the Center for Rare Lung Diseases in the department of respiratory diseases and allergy at Aarhus University Hospital, Denmark, and colleagues wrote.

The most prevalent comorbidities among 150 patients with IPF were arterial hypertension (62%), gastroesophageal reflux disease (46.7%), hypercholesterolemia (45.3%), emphysema (43.3%) and obstructive sleep apnea (41.3%).

The prospective cohort study enrolled adults with IPF (mean age, 72.9 years; 81.3% men) from three tertiary interstitial lung disease referral centers in Denmark from August 2016 to March 2018. Researchers collected various measurements, questionnaires, and medication and medical history from all patients to evaluate comorbidities. Researchers also identified comorbidity clusters and characterized phenotypes using self-organizing maps.

All but one patient had at least one comorbidity. Multimorbidity was common in the cohort.

The researchers identified four multimorbidity clusters; each demonstrated distinct comorbidity profiles, patient characteristics, symptom burden and disease severity. Patients in cluster 1 (n = 43) had significantly fewer comorbidities than those in cluster 2, 3 or 4. Patients in cluster 2 (n = 50) were likelier to have ischemic heart disease and arterial hypertension, hypercholesterolemia, diabetes, chronic kidney disease and OSA. Patients in cluster 3 (n = 38) were likelier to have emphysema, airway obstruction and pain disorders. Patients in cluster 4 (n = 19) were likelier to have anxiety, depression, pain disorders, gastroesophageal reflux disease, emphysema and had a higher number of comorbidities compared with the other clusters.

Patients with fewer comorbidities had better exercise capacity and less dyspnea at baseline. However, researchers observed a trend towards a decline in FVC among patients in cluster 1 compared with cluster 3 (P = .03), a decline in diffusing capacity of carbon monoxide among patients in cluster 1 compared with cluster 3 (P = .02) and cluster 4 (P = .03), and a decline in 6-minute walk distance among patients in cluster 1 compared with cluster 2 (P = .04) and cluster 3 (P = .003).

The researchers reported no significant difference in mortality between the four clusters.

“Increased knowledge of comorbidities will facilitate interventions aimed at prevention and treatment of comorbidities in patients with IPF,” the researchers wrote.