Long-term effects of bosentan on quality of life, survival, safety and tolerability in pulmonary arterial hypertension related to connective tissue diseases

Pulmonary arterial hypertension (PAH) is an important complication of connective tissue diseases (CTD) and especially seen in systemic sclerosis, systemic lupus erythematosis (SLE), and mixed connective tissue disease (MCTD). In systemic sclerosis, PAH is isolated or accompanied by interstitial lung disease and currently, a major cause of mortality. It has been shown to be developed in approximately 10% of cases and annual screening with echocardiography has been recommended. Right heart catheterization is required for definite diagnosis. Limited skin involvement, late onset, Raynaud's phenomenon, digital ulcers, telangiectasias, diminished nail fold capillaries, anti-U3RNP and anticentromere antibodies are known as risk factors for PAH development in systemic sclerosis. Following diffusion lung capacity for carbon monoxide (DLCO) and pro-brain natriuretic peptide (pro-BNP) levels can be helpful for evaluating PAH development. PAH in SLE linked to antiphospholipid antibodies and Raynaud's phenomenon in some studies. MCTD is an overlap syndrome with features of systemic sclerosis, SLE, polymyositis and positive anti-U1RNP antibodies. PAH develops in 9-27% of the patients and the leading cause of mortality in patients with MCTD. Endothelin receptor antagonists, prostacyclin analogs and phosphodiesterase 5 inhibitors are being used in patients with systemic sclerosis. In SLE/MCTD patients with early diagnosis immunosuppressive treatments may be effective.