Introduction

The spectrum of fibrotic ILD ranges from progressive fibrosis to improvement of lung function over time.

Aims

We aimed to evaluate the prognostic value of baseline biomarkers for functional improvement in fibrotic ILD patients.

Methods

This registry-based study included 142 patients with fibrotic ILD as defined by presence of reticulation or honeycombing on initial computed tomography (CT), typical CT findings were scored in six distinct lungs regions. Improvement at 1 year was defined as relative increase of 5% in FVC or 10% in DLCO. Impact of baseline biomarkers on functional improvement was evaluated for all patients as well as for those having received anti-inflammatory therapies.

Results

At one year, 44 (16%) patients showed improvement while 73 (34%) progressed. Older age (p=0.023), lower FVC (%; p=0.017), and blood monocyte count (p=0.046), higher extent of ground glass opacities (p=0.047) and less traction bronchiectasis (TBR; p=0.019) were associated with improvement. Multivariate analyses (MVA) excluding baseline lung function biomarkers found prognostic significance for age <60 years (OR 5.4; 95%CI 1.9-15.4; p=0.002), lactate dehydrogenase >250U/L (LDH; OR 2.5; 95%CI 1.1-5.8; p=0.043) and monocyte count <0.8G/L (OR 3.5; 95%CI 1.1-11.3; p=0.034). In 84 patients treated with anti-inflammatory drugs, MVA only revealed age (OR 8.5 (95%CI 2.1-33.4; p=0.002) as significant predictor of functional improvement.

Conclusions

Younger age, higher LDH and lower monocyte count predicted functional improvement in fibrotic ILD patients, while in those treated with anti-inflammatory drugs, only age had significant implications.