Pharmacological and nonpharmacological interventions to improve symptom control, functional exercise capacity and quality of life in interstitial lung disease: an evidence synthesis

We assessed efficacy and effectiveness of pharmacological and nonpharmacological interventions in improving symptom control, functional exercise capacity and quality of life (QoL) in people living with fibrotic interstitial lung disease (ILD). We summarised evidence from three previous reviews (to June 2014) and conducted an updated search of nine databases and grey literature (2011-2019) (registration: CRD42017065933) for prospective studies of interventions aimed to alleviate symptoms, improve QoL or functional exercise capacity in fibrotic ILD. Data were synthesised through narrative synthesis or meta-analysed as appropriate. Forty-seven studies with 2527 participants were included. From 22 pharmacological studies of 11 different interventions (n=1683), the most tested interventions were bosentan and sildenafil. From 25 nonpharmacological studies, the most tested intervention was for pulmonary rehabilitation/exercise training (PR) (22 studies, n=748). There was an improvement in 6-min walk distance immediately following PR (six studies; n=200, mean difference (MD) (95% CI) 39.9 m (18.2 to 61.5)), but not longer term (3 or 6 months, four studies; n=147, MD 5.3 m (-12.9 to 23.4). Multiple, varied outcome measures were used (e.g. 37 studies assessing dyspnoea used 10 different scales with a lack of reporting of rate of deterioration in outcomes). Evidence gap mapping highlighted the most and least researched symptoms, as dyspnoea and cough, respectively. This evidence synthesis highlights overwhelmingly that the most researched symptom is dyspnoea and the strongest evidence base is for short-term PR. The least researched symptom was cough. Research going forward must focus on prioritising and standardising meaningful outcomes and focussing interventions on neglected symptoms.