PAH linked to methamphetamine use tied to worse heart health
Study also finds poorer exercise capacity for patients vs. other forms of PAH
People with pulmonary arterial hypertension (PAH) related to use of methamphetamine — a potent stimulant only legally available by prescription — tend to have worse heart health and poorer exercise capacity compared with patients with other forms of PAH.
That’s according to a new study, “Methamphetamine-associated pulmonary arterial hypertension: data from the national biological sample and data repository for pulmonary arterial hypertension (PAH Biobank),” published in BMJ Open Respiratory Research.
Methamphetamine, colloquially known as meth, is an addictive drug, and researchers said its abuse is “a growing epidemic.” The drug has many well-established negative impacts on health — among them, it’s been proven that methamphetamine use significantly increases the risk of PAH, a condition characterized by high pressure in the blood vessels of the lungs.
Now, researchers sought to learn more about patient outcomes among people with methamphetamine-related PAH, abbreviated MA-PAH, versus two other forms of the disease: connective tissue disease-associated PAH, or CTD-PAH, and idiopathic PAH, known as IPAH. In CTD-PAH, the disease develops due to an underlying disorder of connective tissue, while in IPAH, the underlying cause is unknown.
Patients with meth-related PAH also had higher rates of depression
In this study, the team conducted an analysis using data from a large database. It involved a total of 42 people with MA-PAH, 715 with CTD-PAH, and 1,073 with IPAH.
Compared with patients with other types of PAH, those with methamphetamine-related disease tended to be younger when they were diagnosed. All three groups were predominantly female, though the proportion of females was notably lower in those with MA-PAH (69.1%) compared with CTD-PAH (90.9%) or IPAH (78.4%).
“In line with prior studies … our observations echo the pattern of a predominantly female distribution in MA-PAH. However, the proportion of females in the MA-PAH group was not as high as in IPAH,” the researchers wrote.
The team noted that, among patients with PAH related to methamphetamine use, males tended to have poorer scores than females on measures of function and exercise capacity.
“This study marks the first to report and compare clinical characteristics … between male and female participants with MA-PAH,” the researchers wrote, though they noted that the low number of MA-PAH patients makes it hard to draw definitive conclusions from these data.
Compared with the other two groups, the MA-PAH group had higher rates of depression and use of antipsychotic medications — consistent with another study that found worse mental health-related quality of life among this patient population. According to the researchers, this may reflect concurrent psychiatric diseases rather than being a cause of MA-PAH.
The researchers also looked at exercise capacity. The predicted distance patients could walk in six minutes, a common measure used to test this, tended to be shorter in the MA-PAH group than the other two groups.
Additionally, the team found that nearly 10% of patients in the MA-PAH group had cardiomyopathy, a form of heart disease. That’s compared with less than 2% of patients in the other groups. The MA-PAH patients also more frequently reported edema, or swelling, which can be a sign of heart disease.
These findings are consistent with the idea that use of methamphetamine can cause heart damage, in addition to increasing the risk of PAH, according to the researchers.
Further research is necessary to identify risk factors and underlying mechanisms of [methamphetamine-related PAH], particularly considering the increasing prevalence of methamphetamine use.
Upon being enrolled in the database, patients with meth-related PAH were less likely to be receiving PAH-specific treatments than were individuals with IPAH, but measures of blood pressure in the lungs were comparable in both groups. MA-PAH and IPAH patients showed no differences in blood flow measures, but the MA-PAH group had significantly higher pulmonary artery pressure and pulmonary vascular resistance — a measure of internal resistance to blood flow within the lung’s blood vessels — compared with CTD-PAH.
“Further research is necessary to identify risk factors and underlying mechanisms of MA-PAH, particularly considering the increasing prevalence of methamphetamine use,” the scientists concluded, noting that “such investigations will contribute to the development of effective prevention and treatment strategies for this condition.”