5-Year Retrospective Review of Diltiazem Associated Deaths
Diltiazem is a calcium channel blocker that is prescribed for the treatment of hypertension, angina pectoris, dysrhythmia and migraines. It is also a common adulterant of illicit drugs, such as cocaine. Acute diltiazem toxicity is infrequently associated with death. We report a retrospective review of all diltiazem related deaths over a 5 year period in Ontario. Our method included review of the history, post-mortem and toxicology reports to gather information about psychosocial issues, access to a prescription of diltiazem, major autopsy findings, manner of death, blood concentrations of diltiazem and its metabolite. From 2010 to 2014 there were 18 diltiazem related deaths, in which 10 deaths were attributed solely to diltiazem. The highest concentration of diltiazem was 18 mg/L in the post-mortem peripheral blood. Lower levels were observed in 2 cases (1.5 and 0.32 mg/L) in which the admission blood was tested up to 1 week after having been drawn. In 12 cases, a prescription to the deceased was documented. The most common cause of death was attributed to drug toxicity. This was largely due to the common presence of the detection of citalopram. No illicit drugs were detected. There was a female predominance (11:7=f:m) and deaths commonly involved an older age group (median: 65 years). The major autopsy findings in nearly all cases (16 cases) demonstrated structural heart disease, including cardiomegaly, ventricular hypertrophy and severe atherosclerotic plaques in the coronary arteries. This underlying structural heart disease suggests an indication for the diltiazem prescription. Additional findings at autopsy included the presence of pill matter within the stomach contents in half of the cases. The most common manner of death was suicide (10 cases). The high frequency of suicide was supported with the high incidence of depression/suicidal ideation in this series. This is the largest reported case series to review diltiazemassociateddeaths. This case series indicates that an advanced forensic toxicologic overview is needed as part of a comprehensive medicolegal death investigation. Otherwise both the cause and manner of death may be misattributed to a natural heart disease, which is often seen in this older age group.
Ellen Yang, Rebekah D Jacques, Jayantha Herath