Researchers noted that alcohol-related deaths were increasing among people in almost every age, race and ethnic group. Their study is published in Alcoholism: Clinical & Experimental Research.

“Taken together, the findings of this study and others suggests that alcohol-related harms are increasing at multiple levels – from ED visits and hospitalizations to deaths. We know that the contribution of alcohol often fails to make it onto death certificates. Better surveillance of alcohol involvement in mortality is essential in order to better understand and address the impact of alcohol on public health,” said Koob.

Other drugs besides alcohol are increasingly involved in overdoses. A recent analysis of over one million urine drug tests conducted by Millennium Health found that positive results for illicit fentanyl rose by 333% since 2013, while positive rates for methamphetamine increased by 486 percent.

That study, published in JAMA Network Open, found that positive rates for heroin and cocaine peaked in 2016 and appear to be declining.

The analysis is similar to a 2019 report from the National Institute on Drug Abuse, which found that drug deaths involving prescription opioids and heroin have plateaued, while overdoses involving methamphetamine, cocaine and benzodiazepines have risen sharply.

Unreliable Data

Just how reliable is the federal data on drug use and overdoses? Not very, according to another study published in Drug and Alcohol Dependence.

Troy Quast, PhD, an associate professor at the University of Florida’s College of Public Health, compared overdose data from the Florida Medical Examiners Commission (FMEC) to drug deaths in a CDC database. Quast found the federal data significantly undercounted overdose deaths in Florida linked to cocaine, benzodiazepines, amphetamines and other drugs.

Florida medical examiners are required by law to wait for complete toxicology results before submitting an official cause of death to FMEC. It often takes weeks or months to identify the exact drug or drugs that cause an overdose. By contrast, the CDC data is based on death certificates filed by coroners and other local authorities, which often don't include detailed toxicology reports. This causes significant differences between the two databases.

Between 2003 and 2017, roughly one-in-three overdose deaths in Florida involving illicit or prescription opioids were not reported by the federal government. The discrepancy wasn’t limited to opioids. Quast also found that nearly 3,000 deaths in Florida caused by cocaine were not included in the CDC database. Overdose deaths involving benzodiazepines and amphetamines were also significantly under-reported.

"The CDC data are widely reported in the news and referenced by politicians, which is problematic since those estimates significantly undercount the true scope of the epidemic for specific drugs," said Quast. "The rate of under-reporting for all overdose deaths in Florida is near the national average, so the problem is not to the state."

This isn’t the first time the reliability of CDC data has been questioned. In 2018, CDC researchers admitted that many overdoses involving illicit fentanyl and other synthetic black market opioids were erroneously counted as prescription drug deaths. As result, federal estimates prior to 2017 "significantly inflate estimates" of prescription opioid deaths.

Even the adjusted estimates are imprecise, because the number of deaths involving diverted prescriptions or counterfeit drugs is unknown and drugs are not identified on 20% of death certificates. When the drugs are listed, many overdoses are counted multiple times by the government because more than one substance is involved.

The federal government is working to improve the collection of overdose data. Over 30 states are now enrolled in the CDC's Enhanced State Opioid Overdose Surveillance program, which seeks to improve overdose data by including toxicology reports and hospital billing records.

In 2017, the program reported that nearly 59 percent of overdose deaths involved illicit opioids like fentanyl and heroin, while 18.5% had both illicit and prescription opioids. Less than 18% tested positive for prescription opioids only.

A recent study of drug deaths in Massachusetts found that only 1.3% of overdose victims who died from an opioid painkiller had an active prescription for the drug – meaning the medication was probably diverted, stolen or bought on the street.