Hiding in Plain Sight: Methamphetamine-Related MIs Not Uncommon

Methamphetamine use is on the rise around the US, with implications for heart health: a new study from California suggests that around one in six MIs occurring in adults up to age 65 years may have been caused by the drug.

These events predominately occur in younger men with adverse social determinants of health, researchers report recently in the Journal of the American Heart Association. Moreover, they are more often fatal than MIs that occur without the use of these “highly addictive and potent synthetic central nervous system stimulants,” the paper notes. “Methamphetamines can provoke deleterious and potentially fatal consequences due to elevated blood pressure, acute vasospasm, and development of premature coronary atherosclerosis.”

Susan X. Zhao, MD (Santa Clara Valley Medical Center, San Jose, CA), the study’s lead author, told TCTMD that most research on how methamphetamines affect the cardiovascular system has thus far focused on pulmonary arterial hypertension and dilated cardiomyopathy/heart failure. By comparison, acute coronary syndromes related to meth have mainly been documented in cases reports and small series.

Public awareness of the cardiovascular harms posed by methamphetamines isn’t as widespread as it is for other illicit drugs, such as cocaine, she said.  At their hospital in Northern California, patients often express surprise when they learn their MI might be related to meth use, especially because much of that use is casual enough that it doesn’t register as an addiction, Zhao commented. “They say: ‘Oh, yeah, I use that every day. I had no idea it was causing anything.’ So that's the incentive for us to look into this condition.”

That such a high proportion of MIs occurred in relation to meth use, as shown here, did come as a surprise, said Zhao. But she also noted that it’s important to remember that the study included only younger adults up to age 65, not elderly patients.

More Readmissions, Higher Death Risk

For the retrospective study, the investigators gathered data from electronic medical records for all 1,309 patients aged 18 to 65 years who presented with ACS due to presumed type I MI and underwent coronary angiography at Santa Clara Valley HealthCare between 2012 and 2022. Excluding cases involving cocaine use or other non-type 1 MIs, 194 (14.8%) of these patients had methamphetamine-associated ACS. Meth use was either self-reported or had been detected on a urine toxicology screen obtained during the index ACS hospitalization.

Compared with patients who didn’t use meth, those who did were younger (median 52 vs 57 years) and were more apt to have nonobstructive CAD (24.3% vs 10.6%; P < 0.001 for both). Rates of hypertension, obesity, and history of atrial fibrillation or stroke were similar between the two groups, though the meth users were less likely to have diabetes, tended to have better kidney function, and had more favorable lipid profiles. LVEF was lower (median 50% vs 55%) among meth users versus nonusers (P < 0.001 for both).

The patients who used methamphetamines were eight times more likely to be homeless than nonusers (25.8% vs 3.2%) and were three times more likely to smoke cigarettes (71.6% vs 21.6%) and to currently drink alcohol (28.9% vs 8.3%; P < 0.001 for all).

Both groups were equally likely to present with STEMI. However, MI with nonobstructive CAD was much more common in the meth users (24.2% vs 10.6%), who as a result were less likely to undergo revascularization (59.3% vs 75.0%; P < 0.001 for both).

All-cause death was more common among users versus nonusers (22.2% vs 14.4%; P = 0.006), as were readmissions for subsequent ACS events (42.3% vs 27.2%; P < 0.001). After adjustment for various factors—age, sex, white race, body mass index, diabetes, current smoking, total cholesterol, creatinine, LVEF, and prior revascularization—methamphetamine use was the strongest predictor of all-cause mortality (HR 2.08; 95% CI 1.40-3.09), followed closely by diabetes (HR 2.01; 95% CI 1.42-2.84).

The high prevalence of meth-associated ACS observed here “likely reflects the high background rate of methamphetamine use in our region rather than a nationwide pattern,” the researchers acknowledge. Still, they stress, it’s important to remember that this “analysis captures only the numerator, those with ACS and methamphetamine use referred for coronary angiography, whereas the broader denominator of meth-angina spectrum disease is likely more prevalent and imposes considerable hidden costs.

“The true clinical, societal, and economic burden of meth-angina, with or without confirmed ACS, remains to be further defined through multicenter studies or large-scale registry data,” the authors continue.

For meth users who’ve had an MI, education is much needed, said Zhao. “If you're just a run-of-the-mill MI [patient], you go home, you get healthy, you take your medications, you stop [eating junk food], and you go exercise. . . . But for this particular segment of MI patients, ‘stop using methamphetamines’ should be as important a part of your secondary prevention as everything else.”

To truly address meth use, however, “public policy will have to change,” she said, adding that the researchers’ next study will explore the financial burden of methamphetamine heart failure.