Surveillance of methadone-related poisonings in Kentucky using multiple data sources

Purpose: The methadone poisoning death rate for Kentucky in the year 2005 was the sixth highest in the US and increased 17-fold from 1999 to 2005. The purpose of this study was to identify and characterize methadone related poisonings in Kentucky using multiple data sources: inpatient hospitalization discharge data, poison control center data, vital statistics mortality data, and Kentucky All Schedule Prescription Electronic Reporting (KASPER) data. Methods: A descriptive analysis study was performed on Kentucky inpatient hospitalization discharge data, Kentucky Regional Poison Center (KRPC) data, Kentucky vital statistics mortality data, and KASPER data. Results: While methadone prescription rates decreased from a peak of 27 prescriptions per 1000 population in the year 2003 to 21 in 2007, there was a statistically significant increase in inpatient hospitalization rates, and KRPC call rates (years 2001-2007), and in mortality rates (years 2001-2005). The highest methadone related inpatient hospitalization rates and mortality rates were observed in the rural Appalachian region of Kentucky. Inpatient methadone related hospitalizations occurred most frequently among males from 25 to 34 years of age and among females from 35 to 44 years of age. Medicare and Medicaid were billed for over half of the patients over the age of 34 hospitalized for methadone related poisoning. The expected payer source for six of the inpatient hospitalization patients was workers' compensation, mostly due to unintentional methadone poisonings at work. Conclusions: Utilizing multiple data sources, the results of this study show that unintentional and intentional methadone related poisonings are a continuing and escalating problem in Kentucky, particularly in the Appalachian region.