Background Interstitial lung disease (ILD) is a frequent entity in patients with rheumatic diseases, worsening the prognosis of those who suffer it (1). Previous studies have used the GAP (Gender, Age, Pulmonary function) model stage system to determine mortality at 1, 2 and 3 years (2). For stage I is 5.6% the first year, 10.9% second and 16.3% the third. GAP II has a mortality of 16.2%, 29.9% y 42.1% for the first, second and third year. For stage III, 39.2%, 62.1% and 76.8% respectively (3)
Objectives To perform GAP model stage system in Dominican patients with Interstitial Lung Disease (ILD) related to Rheumatic Diseases (RD).
Methods This is an observational, cross sectional study, with 42 patients who presented ILD related to RD. The GAP model stage system was determined by using demographic variables and pulmonary function tests such as spirometry and lung diffusion capacity (DLCO).
Results 36 patients were female; the median age was 45±12 years. The mean value for Forced Vital Capacity (FVC) was 72%, Forced expiratory volume in 1 second (FEV1) 73%, and the ratio FEV1/FVC 99%. The DLCO mean value was 66±23 ml/min/mmHg. 35 patients (83.3%) were in stage I, 7 patients (16.6%) in stage II and none in stage III. The statistical significant variables were the time of diagnosis of the RD (p=0.013); with 4.9 years for those in stage I and 10.8 years for stage II; the time of the diagnosis of the ILD (p=0.003) with 2.1 years for patients in stage I and 4.8 years for stage II and smoking (p=0.063).
Conclusions These findings suggest that the GAP model system is an useful tool to stage patients with interstitial lung disease related to rheumatic diseases. It can also help us make changes in treatment based on the stage. Special attention must be paid to those with a longer time of diagnosis of the RD, time of diagnosis of the ILD and/or smoking.
Vij R. Diagnosis and treatment of connective tissue disease-associated interstitial lung disease. CHEST 2013;143(3).
Hoon S. Comparisons of prognosis between surgically and clinically diagnosed idiopathic pulmonary fibrosis using GAP model. Medicine Journal 2016; vol 95 (11).
Ley B. A multidimensional index and staging system for idiopathic pulmonary fibrosis. Ann Intern Med. 2012, 156:684–691.
Disclosure of Interest None declared