Study of Long-term Survival Among PAH Patients in Portugal Shows Progress of Recent Decades

People newly diagnosed with pulmonary arterial hypertension (PAH) in Portugal have survival rates similar to those in other developed countries — and much better than the life expectancy of PAH patients some 30 years ago, a new study found.

Moreover, those patients with congenital heart disease (CHD) — whose outcomes are generally poor — were also found to have improved survival rates, possibly because of recent medical advances and the larger numbers of PAH patients in that country with CHD.

The study,  “Real-world, long-term survival of incident patients with pulmonary arterial hypertension” by Portugese researchers, was published in the journal Revista Portuguesa de Pneumologia.

The first analysis of the epidemiology (or incidence and nature) of PAH and its subgroups — idiopathic (IPAH), hereditary (HPAH), and drug-related (DPAH) — took place in a National Institutes of Health (NIH) registry in the late 1980s, an era lacking specific therapies. Recorded survival rates of 1, 3, and 5 years were 68%, 47% and 37%, respectively. Since that time, however, treatment advances have considerably improved overall survival, with one-year rates now typically between 85% and 95%.

Because data on long-term outcomes in PAH patients in Portugal are scarce, a team led by researchers at the Centro Hospitalar e Universitário de Coimbra aimed to estimate the survival over time among newly diagnosed patients. The study’s primary endpoint was all-cause mortality, while a secondary measure was a combination of all-cause mortality and admission for decompensated heart failure, or  a sudden worsening in symptoms associated with heart failure.

All PAH cases between January 2009 and November 2015 were included in the prospective cohort study. Researchers analyzed 1-, 3-, and 5-year survival and compared it with the historical PAH survival rates estimated by NIH.

Analysis found that most PAH patients were female (68%), with a mean age of 48.  Congenital heart disease (CHD) was seen in almost half of these patients (48%), while other common subgroups were people with connective tissue disease (25%), IPAH (12%), and HPAH (1.5%).

Survival rates at 1, 3 and 5 years were 95%, 77% and 71%, respectively, and were similar across the different PAH subgroups — and comparable to those recorded in more recent studies in countries that include the U.S., France and the U.K.

Values of B-type natriuretic peptide (BNP, a hormone produced by the heart and released in response to changes in pressure, which can be related to heart failure) and male gender were predictors of death, however. In fact, further dividing these patients into two groups — women with BNP levels lower than the median and men with BNP levels higher than the median — showed that all-cause mortality rates and the combined measure (death plus admission for decompensated heart failure) were higher in the men.

Data showed improved survival for IPAH, HPAH and DPAH patients in comparison with the NIH cohort, but the difference was not statistically significant.

Overall, CHD patients also “displayed a numerically higher survival rate and overall better prognosis,” the researchers wrote, possibly because “our cohort [unlike studies elsewhere] … reflect, but may be not limited to, a larger population of PAH-CHD patients, usually with better overall prognosis,” and improvements in treatment options since the 1980s “when most of these patients were born.”

The team believes that the higher PAH survival rates observed in recent years “reflect access to contemporary PAH treatment and constitute a strong incentive to the continuous work developed by all members involved in caring for this condition.” At the same time, the results “reinforce the need for a long-term nationwide registry, pursuing better care for PAH patients.”