Elevations in creatine phosphokinase had sensitivity and specificity of 99 and 23 percent, respectively, for identifying myocarditis
WEDNESDAY, Jan. 4, 2023 (HealthDay News) — Immune checkpoint inhibitor (ICI) myocarditis is associated with changes in noncardiac biomarkers, with elevated creatine phosphokinase (CPK) associated with myocarditis development and all-cause mortality, according to a study published in the December issue of JACC: CardioOncology.
Alexi Vasbinder, Ph.D., R.N., from the University of Michigan in Ann Arbor, and colleagues examined biomarker trends of patients on an ICI and their association with the incidence of ICI myocarditis among adults who received at least one dose of an ICI at Michigan Medicine between June 2014 and December 2021.
The researchers found that 1.0 percent of the 2,606 patients were diagnosed with ICI myocarditis. Patients with myocarditis had elevated high-sensitivity troponin T, alanine aminotransferase, aspartate aminotransferase, CPK, and lactate dehydrogenase (100, 88.9, 85.2, 88.9, and 92.6 percent, respectively) at diagnosis. In an independent cohort of 30 patients with biopsy-confirmed ICI myocarditis, the findings were confirmed. Elevations in at least three biomarkers were seen for 95 percent of patients with ICI myocarditis compared with 5 percent of patients without myocarditis. In a multivariable analysis, among the biomarkers, only CPK was associated with myocarditis development and all-cause mortality (per 100 percent increase: hazard ratios, 1.83 and 1.10, respectively). Elevations in CPK had sensitivity and specificity of 99 and 23 percent, respectively, for identifying myocarditis.
“Patient[s] suspected of immune checkpoint myocarditis should have creatine phosphokinase levels measured,” a coauthor said in a statement. “If low, or within normal limits, then the diagnosis of immune checkpoint myocarditis is highly unlikely.”