Whether a pulmonary arterial hypertension patient has scleroderma has no bearing on the outcome of their PAH after they receive a lung transplant, a study reports.
Scleroderma, also known as systemic sclerosis, is a chronic autoimmune disease caused by abnormal production of connective tissue. It primarily affects the skin but can progress to the lungs and other organs.
The condition is characterized by loss of tissue flexibility. This can lead to constricted lung blood vessels, increasing blood pressure and decreasing the flow of oxygen-carrying blood to the lungs.
Five to 12 percent of scleroderma patients have PAH, which is associated with a poor outcome. Medicines developed in recent years to target PAH symptoms have increased the median survival of these patients from 12 months to between three and four years. Despite the PAH treatment improvements, many patients still require a lung transplant, however.
Researchers decided to compare the outcomes of PAH patients with scleroderma who had either lung or heart transplants and the outcomes of PAH patients without scleroderma who had transplants. The results, “Lung or Heart-Lung Transplant in Pulmonary Arterial Hypertension: What Is the Impact of Systemic Sclerosis?,” were published in Experimental and Clinical Transplantation.
The study involved 51 PAH patients, nine with scleroderma-related PAH. The patients without scleroderma had worse PAH symptoms before a transplant than those with scleroderma. Their lung blood pressure was higher and their blood-flow resistance higher.
There was no significant difference in the groups’ death rates, researchers found. None of the scleroderma-related patients died in the first year after a transplant, although 29 percent died by the end of the second year. The figures for non-scleroderma-related patients were 13 percent by the end of the first year and 24 percent by the end of the second.
Eighty-sixty percent of scleroderma-related patients died within five years of a transplant, versus 53 percent of non-scleroderma patients, but researchers said the difference was not statistically significant. This was probably due to the small number of patients in the study.
The research team said studies covering more patients would probably shed more light on the long-term outcomes of these patients.
“Pulmonary arterial hypertension patients — with versus without systemic sclerosis-associated disease — have comparable short-term and two-year outcomes after lung or heart-lung transplant,” the researchers wrote, even though scleroderma-related PAH patients have better PAH symptoms before a lung transplant.