SACRAMENTO, Calif.- Young people who use methamphetamine, an addictive, illegal stimulant also known as meth, crank, crystal and speed, more than triple their risk of cardiomyopathy, a disease of the heart muscle, according to a study led by a researcher at UC Davis Health System.
Khung-Keong Yeo, a clinical fellow in the UC Davis Division of Cardiovascular Medicine, led a team that reviewed the medical records of 107 patients ages 45 and under who were discharged from a medical center in Honolulu from January 2001 through June 2004 with a diagnosis of cardiomyopathy or heart failure. Yeo led the study while he was a medical resident at the University of Hawaii. The study was published in the February issue of the American Journal of Medicine.
According to the authors, the analysis is the first to show an association between methamphetamine use and cardiomyopathy. Among the patients studied, four of every 10 with cardiomyopathy used methamphetamine.
Cardiomyopathy is a disease of the muscular tissue of the heart known as the myocardium. People with cardiomyopathy are at risk for heart failure and arrhythmia, a condition in which the heartbeat is abnormal, as well as sudden cardiac death.
Yeo and his research team compared the 107 patients diagnosed with cardiomyopathy or heart failure with 114 age-matched patients discharged without signs of heart problems. After adjusting for other risk factors, including body weight and kidney failure, the researchers found that methamphetamine users had a 3.7 times greater risk of cardiomyopathy compared to the patients who did not use the illegal drug.
In addition to facing to a higher risk of cardiomyopathy, methamphetamine users were at an increased risk of developing a more severe form of the disease, Yeo and his colleagues found. Their review suggests that the hearts of cardiomyopathy patients who use methamphetamine pump significantly less blood than do those of cardiomyopathy patients who do not use methamphetamine.
Although the study was not designed to determine why methamphetamine use increases cardiomyopathy risk, Yeo said that ‘there are many speculated causes, including spasm of the arteries supplying the heart, direct toxicity, elevated blood pressure and heart rate, and atherosclerosis, or hardening of the arteries.’
Other members of the research team were from the John A. Burns School of Medicine at the University of Hawaii, the Washington Hospital Center in Washington, D.C., and UC San Francisco.
The study was funded by the Queen Emma Research Fund and supported by the Hawaii Residency Programs Tobacco Reduction Project.