Fentanyl-associated fatalities among illicit drug users in Wayne County, Michigan (July 2005-May 2006).

BACKGROUND: During the summer of 2005, multiple cities in the United States began to report outbreaks of fentanyl-associated fatalities among illicit drug users. The objectives of this study were to (1) determine if an outbreak of fentanyl-associated fatalities occurred in mid-2005 to mid-2006 and (2) to examine trends and compare features of fentanyl-contaminated heroin-associated fatalities (FHFs) with non-fentanyl, heroin-associated fatalities (NFHFs) among illicit drug users. METHODS: Baseline prevalence of fentanyl- and heroin-associated deaths was estimated from January to May 2005 based on recorded cause of death (determined by the medical examiner (ME)) using the Wayne County, MI, USA toxicology database. The database was then queried for both FHFs and NFHFs between July 1, 2005 and May 12, 2006. A FHF was defined as having fentanyl or norfentanyl (metabolite) detected in any postmortem biological sample and either (1) detection of heroin or its metabolite (6-acetylmorphine) and/or cocaine or its metabolite (benzoylecgonine) in a postmortem biological specimen or (2) confirmation of fentanyl abuse as the cause of death by the ME or a medical history available sufficient enough to exclude prescription fentanyl or other therapeutic opioid use. A NFHF was defined as detection of heroin, 6-acetylmorphine (heroin metabolite) or morphine in any postmortem biological specimen, heroin overdose listed as the cause of death by the ME, and absence of fentanyl detection on postmortem laboratory testing. Information was systematically collected, trended for each group and then compared between the two groups with regard to demographic, exposure, autopsy, and toxicology data. Logistic regression was performed using SAS v 9.1 examining the effects of age, gender, and marital status with fentanyl group status. RESULTS: Monthly prevalence of fentanyl-associated fatalities among illicit drug users increased from an average of two in early 2005 to a peak of 24 in May, 2006. In total, 101 FHFs and 90 NFHFs were analyzed. The median age of decedents was 46 and 45 years for the fentanyl and non-fentanyl groups, respectively. Fentanyl-contaminated heroin-associated fatalities (FHFs) were more likely to be female (p = 0.003). Women aged over 44 years (OR = 4.67;95 % CI = 1.29-16.96) and divorced/widowed women (OR = 14.18;95 % CI = 1.59-127.01) were more likely to be FHFs when compared to women aged less than 44 years and single, respectively. A significant interaction occurred between gender and age, and gender and marital status. Most FHFs had central (heart) blood samples available for fentanyl testing (n = 96; 95 %): fentanyl was detected in most (n = 91; 95 %). Of these, close to half had no detectable heroin (or 6-acetylmorphine) concentrations (n = 37; 40.7 %). About half of these samples had detectable cocaine concentrations (n = 20; 54 %). Median fentanyl concentration in central blood samples was 0.02 µg/ml (n = 91, range <0.002-0.051 µg/ml) and 0.02 µg/ml (n = 32, range <0.004-0.069 µg/ml) in peripheral blood samples. The geometric mean of the ratio of central to peripheral values was 2.10 (median C/P = 1.75). At autopsy, pulmonary edema was the most frequently encountered finding for both groups (77 %). CONCLUSION: Illicit drugs may contain undeclared ingredients that may increase the likelihood of fatality in users. Gender differences in fentanyl-related mortality may be modified by age and/or marital status. These findings may help inform public health and prevention activities if fatalities associated with fentanyl-contaminated illicit drugs reoccur.

Gamma butyrolactone (GBL) and gamma valerolactone (GVL): similarities and differences in their effects on the acoustic startle reflex and the conditioned enhancement of startle in the rat.

Gamma butyrolactone (GBL) is metabolized to gamma hydroxybutyrate (GHB) in the body. GHB is a DEA Schedule 1 compound; GBL is a DEA List 1 chemical. Gamma valerolactone (GVL) is the 4-methyl analog of GBL; GVL is metabolized to 4-methyl-GHB; GVL is NOT metabolized to GBL or GHB. The effects of GBL (18.75-150 mg/kg), GVL (200-1600 mg/kg) or vehicle on the acoustic startle reflex (ASR), and the classically-conditioned enhancement of startle, the Startle Anticipated Potentiation of Startle (SAPS) response were studied in male rats. Both compounds produced a dose-dependent reduction of ASR, with GBL 5-7 times more potent than GVL. In contrast, GBL treatment significantly reduced SAPS at doses that exerted only moderate effects on ASR, whereas GVL exerted little or no effect on the SAPS, except at doses that produced pronounced reductions in Noise Alone ASR. In a second experiment, rats were tested for Noise Alone ASR behavior following treatment with a single mid-range dose of GBL (75 mg/kg), GVL (400mg/kg) or vehicle; immediately following startle testing the animals were sacrificed and their brains and blood were collected for determination of GHB, 4-methyl-GHB, GBL and GVL. GHB was found in measurable concentrations in all of the blood specimens and 6 (of 8) of the brain specimens from the GBL-treated subjects. 4-Methyl-GHB was found in measurable concentrations in all of the blood and brain specimens of the GVL-treated subjects; the change in startle amplitude was inversely correlated to the brain concentrations of these compounds. These findings confirm the differences in the metabolic fate of GBL and GVL as pro-drugs for the formation of GHB and 4-methyl-GHB, respectively. Moreover, the dissimilarity in effect profile for GBL and GVL on ASR versus SAPS behaviors suggests that different receptor(s) may be involved in mediating these behavioral effects.

Analysis of GHB and 4-methyl-GHB in postmortem matrices after long-term storage.

Postmortem heart blood, peripheral blood, vitreous humor, urine, and bile specimens from 26 autopsy cases were analyzed for the presence of gamma-hydroxybutyric acid (GHB) and gamma-methyl gamma-hydroxybutyric acid (4-Me-GHB) after long-term freezer storage. Cases were selected for which exogenous GHB, gamma-butyrolactone (GBL), gamma valerolactone (GVL), or 1,4-butanediol use was not suspected. One documented positive GHB case subjected to the same storage conditions was also evaluated for comparison. Specimens did not contain any preservatives or additives except heart blood, which contained sodium fluoride (2% w/v). The results of the analysis for GHB in vitreous humor (n = 26) demonstrated, with one exception, concentrations below the limit of detection for the method (5 mg/L). In the exception case, the value was determined to be 7 mg/L. Documented cases of GHB positive fatalities showed vitreous humor concentrations (n = 6) that exceeded this range by a factor of 12 or more. There was no apparent relationship between storage times and GHB concentrations. The data developed in this study demonstrate a postmortem endogenous range for GHB in vitreous humor that is less than or equal to 7 mg/L. Studies of the stored GHB-positive case demonstrated no significant change in concentration over the time period studied. None of the specimens analyzed in this study contained detectable amounts of 4-Me-GHB. This would support the contention that when 4-Me-GHB is detected, it is most likely due to the exogenous consumption of GVL.

Apparent suicidal carbon monoxide poisonings with concomitant prescription drug overdoses.

We report four separate suicides by apparent motor vehicle-related carbon monoxide (CO) poisoning in which complete toxicological analysis showed the absence of, or lower than expected, percent carboxyhemoglobin saturation and high concentrations of concomitant prescription drugs. These cases, within a population of 71 apparent CO suicides from the Wayne County Medical Examiner's Office over 1998-2004, represent cases where additional factors are in play. Multiple modalities (CO poisoning and drug overdose) and/or undetectable carbon dioxide poisoning from the vehicle exhaust of cars manufactured after laws regulating vehicle emissions were enacted are examples of additional factors that require consideration in these selected cases. All four cases demonstrated some degree of decomposition, so the possible loss of CO could not be ruled out. The need for full toxicological analysis in apparent suicidal CO poisoning is emphasized.