The prevalence of HIV-associated pulmonary arterial hypertension (PAH) hasn't changed much since highly active antiretroviral therapy (HAART) became available, according to results of a prospective study from France.

Among 7,648 consecutive HIV-positive adults from 14 HIV clinics in France, the study team identified a total of 35 cases of PAH, yielding a prevalence of 0.46 per cent.

This figure is very similar to the 0.50 per cent prevalence reported in 1991, Dr. Olivier Sitbon of Hopital Antoine Beclere, Clamart, and colleagues note in the January 1st issue of the American Journal of Respiratory and Critical Care Medicine.

PAH was identified through screening with a predefined algorithm that included a dyspnea questionnaire, transthoracic Doppler echocardiography, and right heart catheterization. PAH was diagnosed if mean pulmonary arterial pressure at rest was 25 mm Hg or greater (with capillary wedge pressure no greater than 15 mm Hg), or 30 mm Hg or greater on exercise.

The severity of PAH in newly diagnosed cases (n = 5) was less than that in the established cases (n = 30). "However, such cases need close monitoring, as HIV-PAH patients may have a rapidly progressive disease and a poor prognosis when in New York Heart Association class III-IV," the investigators note.

In an attempt to identify predictive factors, Dr. Sitbon and colleagues compared patients with and without PAH but found few differences. "The most notable difference was a higher proportion with HIV acquired from intravenous drug use in the subset with PAH than in those without PAH. This possible susceptibility has already been described by others."

They conclude: "Given the current good long-term prognosis of patients with HIV, the severity of PAH in HIV-infected patients, and the absence of predictive factors, careful screening for PAH is warranted for patients with unexplained dyspnea."