A poster presentation at the joint 2008 ICAAC / IDSA meeting in Washington, DC revealed a surprisingly high rate of a serious heart condition called pulmonary arterial hypertension, or PH, in people with HIV. The condition is high blood pressure in the pulmonary artery, the main artery leading from the heart to the lungs.
PH is not readily diagnosed due its lack of symptoms. It often emerges later in HIV disease as a more life-threatening condition. It is more common in people with HIV, even more so for those with symptomatic diseases, reaching a rate of about 1 in every 200 people with AIDS in the pre-HAART era.
This retrospective study sought to find the rate of PH separate from several known risk factors. HIV is an independent risk factor for PH while injection drug use (IDU), excessive alcohol use and smoking also increase its risk. The study evaluated the rate of pulmonary artery systolic dysfunction, which is abnormal peak pressure in the pulmonary artery. People whose HIV disease was well controlled on HAART were divided into two groups: those with and those without PH.
The study, conducted at the National Naval Medical Center, included 91 people who averaged 37 years in age, CD4 counts of 583, nearly 11 years living with HIV, and 5.4 years on HAART. These factors did not vary much between the two groups. Viral loads were also similar between them. Extensive medical histories were taken to exclude risks of heart disease, including genetic factors and lifestyle issues such as smoking and IDU.
The results showed a 5.5% rate of PH in this cohort (5 men total, 2 black and 3 white), which is a high rate compared to similar studies of PH. However, there were no clinical markers that were associated with this rate. In those with PH, the condition was mild and without symptoms. CD4 counts and viral loads did not affect the risk. Other risk factors also did not relate to PH such as cardiac risk factors, lowest-ever CD4 count, use of protease inhibitors, or high risk for AIDS.
Three of the five with PH also had a diastolic dysfunction, though this was statistically not significant. Although other studies show that HAART lowers the risk of PH, this cohort could not draw that conclusion. More prospective study needs to determine whether HIV-positive people on potent therapy with mild PH will eventually develop symptomatic PH. For more information on this condition, read Project Inform's publication, Pulmonary Hypertension and HIV.