Similar Survival Rates for PAH Patients With HIV and IPAH, FPAH
The short-term survival rate of patients with both human immunodeficiency virus (HIV) and pulmonary arterial hypertension (PAH) — dubbed HIV-PAH — is similar to that of people with idiopathic or familial forms of PAH, according to the results of a Spanish study spanning 20 years.
Patients with HIV-PAH also were found to have a better functional status, meaning they had fewer limitations on their regular daily activities than those with the other disease types.
“The short-term prognosis of patients with HIV-PAH was slightly better than that of patients with IPAH/FPAH and similar when they were age-and sex-matched, despite a better functional status,” the researchers wrote, adding, “Heart failure was the main cause of death, although HIV-specific causes of death also contributed relative weight.”
Pulmonary hypertension (PH) is broadly characterized by increased pressure in the arteries providing blood to the lungs. PAH, a rare type of PH, can have several underlying causes, including genetics — which result in familial forms — and viral infections like HIV. The disease also can be due to unknown causes, in which case it’s known as idiopathic.
The human immunodeficiency virus is the leading cause of PAH worldwide, and HIV patients with PAH have a significantly worse prognosis than those without PAH. Mortality in these patients is usually associated with PAH complications rather than reasons directly related to HIV infection.
To learn more about survival rates for these patients, a team of researchers from hospitals in Spain evaluated and compared the disease characteristics, treatment patterns, and prognoses of those with HIV-PAH and people with familial or idiopathic PAH. The study involved a group of 132 HIV-PAH patients from the Spanish PAH registry and 739 people with IPAH/FPAH.
Overall, HIV-PAH accounted for nearly 7% of PAH patients in the registry between 1998 and 2018. Those with HIV-PAH tended to be younger, with a median age of 34.4 compared with 51.3 years for the IPAH/FPAH patients. The HIV-PAH patients also were more frequently male.
The researchers noted that, prior to 2010, injectable drug use was the most frequent risk for HIV infection, after which the most common risk was via sexual transmission.
Among clinical symptoms, chest pain and respiratory function were significantly worse in the HIV-PAH group — thought this may be related to other high-risk behaviors, such as tobacco use.
Functional class — a classification used to rate how sick patients are — was worse among IPAH/FPAH patients, meaning that they were more limited in their physical activities. Likewise, the levels of NTproBNP, an indicator of heart failure, also were higher in this group.
One reason for a worse functional status among those with IPAH/FPAH may be a delayed diagnosis compared with the HIV group, the researchers proposed, although that theory could not be confirmed in this study.
A majority of those in the HIV-PAH group (88.4%) were treated with antiretrovirals, an HIV therapy. For patients treated for PAH, a single oral therapy was the preferred method of treatment in both groups.
Dual therapy was more common in IPAH/FPAH patients than those with HIV-PAH, and occurred significantly more often after 2009, which reflects changes in treatment paradigms.
During an average follow-up of just over four years, there were 41 deaths reported among the HIV-PAH patients (31.1%) and 77 deaths (10.4%) among the IPAH/FPAH patients.
Since the individuals with IPAH/FPAH were, on average, older — which can affect survival — the researchers selected a subset of age- and sex-matched patients to compare with those with HIV.
In this analysis, survival rates were similar between the two groups. Specifically, the one-year survival rate for HIV-PAH patients was 93.6%, while the three-year rate was 81.8%, and the five-year rate was 74%. For the matched IPAH/FPAH patients, the five-year rate was 93.9%, while survival at three years was 77.7%, and at five years, 64.6%.
Heart failure was the leading cause of death in both groups, but occurred more often in IPAH/FPAH (48% vs. 24%). Cancer, a common cause of mortality in HIV patients, was an additional significant cause of death in the PAH-HIV group at 17.1%.
“Survival estimates for HIV-PAH have varied over time, mainly due to the availability of treatment for HIV and PAH. As therapies for both diseases have advanced and treatment strategies have improved, survival estimates seem to be similar,” the researchers wrote.
“Moreover, our study has shown an improved prognosis among the more contemporary [groups] of HIV-PAH patients (up to 2018) … compared to previous reports,” they added.