Cause and manner of death and phase of the blood alcohol curve

In a large number of forensic autopsies (N = 28,184) the concentrations of ethanol in femoral blood and bladder urine were determined and the urine-to-blood concentration ratios of ethanol were calculated. Based on the differences in ethanol concentration between urine and blood, the deaths were classified as having occurred during the absorptive, the peak or the post-absorptive phase of the blood-alcohol curve. Most people died in the post-absorptive phase, N = 24,223 (86%), whereas 1538 individuals (5.5%) were still absorbing alcohol and 2423 (8.6%) were at or close to the peak BAC at time of death. Both blood-alcohol concentration (BAC) and urine-alcohol concentration (UAC) were significantly higher in the post-absorptive phase (p < 0.001). The proportions of people dying in the absorptive and peak phases increased with advancing age. The cause of death (CoD) and manner of death (MoD) according to death certificates were compared with phase of the blood-alcohol curve using a multinomial regression model with and without making adjustment for possible effects of age, gender and BAC. The relative risk (RR) and relative risk ratios (RRR) showed some associations between CoD and phase of the blood-alcohol curve. Undetermined MoD was significantly higher in the absorptive phase compared with the post-absorptive phase (RRR = 2.12). Deaths related to esophagus, stomach and duodenum (RRR = 2.04) and alcoholic liver diseases (RRR = 1.85) were significantly higher at or close to peak phase compared to the post-absorptive phase. Road-traffic fatalities were more prevalent in the peak BAC phase (RRR = 1.33) and deaths by accidental falls were less in the absorptive phase (RRR = 0.58) compared with the post-absorptive phase. The phase of alcohol intoxication seems relevant to consider by forensic experts when alcohol-related deaths are investigated.