Drug overdose death rates in women in the United States have increased by 260 percent in the past two decades, according to a new report.

The authors of the report, published today (Jan. 10) by the Centers for Disease Control and Prevention (CDC), described the drug overdose death rates among women as "unacceptably high," underscoring the need for targeted efforts to reduce the number of drug overdose deaths among women.

The researchers looked at overdose death rates among U.S. women ages 30 to 64 from 1999 to 2017. In 1999, there were 6.7 overdose deaths per 100,000 women, or 4,314 total overdose deaths, according to the report. By 2017, that rate had risen to 24.3 deaths per 100,000 women, meaning 18,110 women in the selected age group died from an overdose that year. [America's Opioid-Use Epidemic: 5 Startling Facts]

The rates of opioid overdose deaths among women ages 30 to 64 increased by 492 percent, from 2.6 deaths per 100,000 women in 1999 to 15.5 deaths per 100,000 women in 2017, according to the report. The largest increase was for deaths involving synthetic opioids such as fentanyl (a rise of 1,643 percent), followed by heroin (915 percent) and prescription opioids (485 percent).

Drug overdose death rates increased for other drugs as well, including cocaine, benzodiazepines and antidepressants.

Age shifts

The largest increase in overdose death rates over the study period was found among women ages 55 to 64, where rates rose by nearly 500 percent from 1999 to 2017. Overdose death rates also rose in women ages 35 to 39 and 45 to 49 by approximately 200 percent, and in women ages 30 to 34 and 50 to 54 by 350 percent.

In 2017, overdose death rates were highest overall among women ages 50 to 54. That year, the overdose death rate was 28.2 deaths per 100,000 women in that age group. In 1999, the highest rate was found in women ages 40 to 44, at 9.6 deaths per 100,000 women.

The researchers also found that the average age of overdose death among women increased by 2.8 years, from 43.5 years in 1999 to 46.3 years in 2017. What's more, the average age of women dying from drug overdoses increased for every drug class with the exception of synthetic opioids. This finding is further supported by previous studies that have found a recent increase in overdose deaths and drug-related emergency department visits for women ages 45 to 64, the researchers wrote.

Study limitations

The report is based on data from the National Vital Statistics System, a database of death certificates in all 50 U.S. states and the District of Columbia. Only deaths in which the underlying cause was drug overdose were included in the report. Cases where more than one drug was listed as a cause of death were counted in multiple categories — for example, if a death certificate mentioned both heroin and cocaine as a cause of death, the researchers would count it as one heroin overdose death and one cocaine overdose death. What's more, certain overdose deaths may be the result of the combination of drugs used, the researchers noted.

The researchers also noted that estimates of the drugs involved in overdose deaths can be affected by how each death was investigated. For example, they noted, toxicology testing can't distinguish whether a person who died from a fentanyl overdose had taken pharmaceutical fentanyl or illegally manufactured fentanyl. In addition, changes in testing over time — for example, the decisions to test for a wider range of substances — could lead to some of the increases described in the report.

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