Relating cocaine blood concentrations to toxicity--an autopsy study of 99 cases

We conducted a retrospective study of 48 men with cocaine-related deaths (CTOX), and a control group of 51 male cocaine users who died of lethal trauma (TRAU). Regression analysis and multiple t-tests were used to assess the relationship between cocaine and benzoylecgonire concentrations as well as autopsy measurements.

Mean age was similar (35.9 vs 34.8 years, p = .549). Cocaine blood concentrations were not significantly different (1.12 vs .487 mg/L, p = .10), but mean BE concentrations were higher in CTOX (1.54 vs .946 mg/L, p = .018). CTOX decedents had a lower Body Mass Index (BMI) (24.6 vs 30.6, p = < .0001), larger hearts (426 vs 369, p = .009), and heavier lungs, livers, and spleens (1275 g vs 1007 g, p = .009, 1896 g vs 1628 g, p = .008, 193 g vs 146 g, p = .001).

(1) Blood cocaine concentrations in cocaine-related deaths are indistinguishable from postmortem concentrations in recreational users, but BE is higher in cocaine-related deaths. (2) Increased lung, liver and spleen weights are consistent with cocaine induced heart failure, but (3) Decreased BMI and increased heart weights in CTOX must be a consequence of long term cocaine use. Cardiac alterations may explain why equal blood cocaine concentrations may be lethal in some cases and innocuous in others, (4) Isolated measurements of postmortem cocaine and BE blood concentrations cannot be used to assess, or predict toxicity.