Rationale: Inflammation is associated with symptoms in many chronic illnesses; however, this link has not been established in pulmonary arterial hypertension.
Objectives: The objective of this study was to investigate the association between inflammatory markers and quality of life-related symptoms in patients with pulmonary arterial hypertension. We hypothesized that higher circulating IL-6 and tumor necrosis factor-α levels would be associated with worse quality of life-related symptoms.
Methods: We performed a secondary analysis using baseline and 3-month assessments of 62 subjects in a clinical trial of aspirin and simvastatin to determine the association between plasma IL-6 and tumor necrosis factor-α levels and the Medical Outcomes Study Short Form-36 subscales (pain, vitality, mental health).
Measurements and main results: The mean age was 49.7±13.4 years; 87% were female. Higher IL-6 levels were significantly associated with lower Medical Outcomes Study Short Form-36 subscale scores, indicating worse bodily pain, vitality, and mental health (all P<0.01). Higher tumor necrosis factor-α levels were significantly associated with increased bodily pain, but better mental health scores.
Conclusions: IL-6 and tumor necrosis factor-α levels are associated with certain quality of life domains in patients with pulmonary arterial hypertension. Clinical trial registered with www.clinicaltrials.gov (NCT00384865).
Keywords: fatigue; interleukin-6; pain; pulmonary arterial hypertension; tumor necrosis factor-α.