Nutrition in patients with idiopathic pulmonary fibrosis: Critical issues analysis and future research directions

In idiopathic pulmonary fibrosis (IPF), several factors may have a negative impact on the nutritional status, including an increased respiratory muscles load, release of inflammation mediators, the coexistence of hypoxemia, and physical inactivity. Nutritional abnormalities also have an impact on IPF clinical outcomes. Given the relevance of nutritional status in IPF patients, we sought to focus on some critical issues, highlighting what is known and what should be further learned about these issues. We revised scientific literature published between 1995 and August 2019 by searching on Medline/PubMed and EMBASE databases including observational and interventional studies. We conducted a narrative review on nutritional assessment in IPF, underlining the importance of nutritional evaluation not only in the diagnostic process, but also during follow-up. We also highlighted the need to keep a high level of attention on cardiovascular comorbidities. We also focused on current clinical treatment in IPF with Nintedanib and Pirfenidone and management of gastrointestinal adverse events, such as diarrhea, induced by these antifibrotic drugs. Finally, we concentrated on the importance of pulmonary rehabilitation program, including nutritional assessment, education and behavioral change, and psychological support among its essential components. More attention should be devoted to the assessment of the undernutrition and overnutrition, as well as of muscle strength and physical performance in IPF patients, taking also into account that an adequate clinical management of gastrointestinal complications makes IPF drug treatments more feasible.