In Colombia, an increase in drug overdoses is widely reported, especially among young women

Overdose rates in Colombia involving illicit opioids, hallucinogens, stimulants and psychotropic tranquilizers increased sharply from 2018 to 2021, driven mainly by overdoses among young women, according to a study from Columbia University’s Mailman School of Public Health. Drug overdoses increased 356% from 8.5 to 40.5 per 100,000 people from 2010 to 2021. The findings were published in the American Journal of Public Health.

The study is the first to describe national trends in overdose rates, including overdoses from prescription and illicit drugs and alcohol, among different population groups in Colombia.

“The pandemic in particular contributed to higher levels of stress and mental health problems, including depression and anxiety in Colombia, similar to other countries,” said Silvia Martins, M.D., Ph.D., professor of epidemiology at Columbia Mailman School and lead author of the study. “Higher prescribing rates and use of tranquilizers/sedatives/antidepressants in Colombia during the pandemic, due to experiences of higher levels of anxiety, sadness, and sleep problems, may have led to excessive drug use. This was more pronounced among women.”

Nearly 14% of people who used substances in 2020 met criteria for a substance use disorder.

Based on the results of the 2019 National Survey on Substance Use (CNSSU, Estudio Nacional de Consumo de Sustancias Psicoactivas de Colombia, 2019), researchers found that substance use has increased in the country over the past three decades for most substances. There was only a small decrease in the use of alcohol, cannabis and cocaine in 2019 compared to 2013.

To examine trends in overdose rates from 2010 to 2021, by substance type, gender, age group and intent, as well as socio-demographic characteristics, the researchers also used data from SIVIGILA, a national public health surveillance system, from 2010 to 2021, a mandatory reporting system to identify health events.

The SIVIGILA data included 127,087 substance use-related overdoses among people aged 10 years and older, of whom 54% were male, 75% were persons aged 10–34 years, 72% had at least some form of secondary school education or higher, and 51% and 38%, respectively, were persons contributing to the health system or receiving subsidies.

The information was used to group overdoses by substance type into the following categories: hallucinogens; stimulants (including prescription stimulants, cocaine, and methamphetamine); opioids (including prescription opioids, heroin, methadone, and buprenorphine); inhalants; tranquilizers, sedatives, and antidepressants; and cannabis.

The researchers identified the most common multi-substance combinations during the study period and the number of overdoses caused by these combinations.

The most commonly reported drugs were tranquilizers/sedatives/antidepressants (43%), cannabis (16%), stimulants (16%), alcohol (16%), and opioids (6%). The majority (95%) of stimulant overdoses were due to cocaine, while opioid overdoses were primarily due to prescription opioids (74%).

Overdose rates for tranquilizers/sedatives/antidepressants and opioid overdoses increased over the study period, and grew more rapidly after 2018. Drug overdoses involving cannabis and stimulants also increased until 2017, but declined thereafter. Among women, the greatest increase in overdose rates was for tranquilizers/sedatives/antidepressants, which increased more rapidly from 2018 to 2021 (from 12 to 33 per 100,000, respectively).

“More research is needed on risk factors, motivations for use, and sources of these medications to improve harm reduction interventions and policies,” said Julian Santaella-Tenorio, DrPH, a professor at the Universidad Pontificia Javeriana in Cali, Colombia, a former Columbia DrPH student and lead author of the study.

“We also believe that screening for suicide risk and access to additional mental health services targeting suicidal thoughts or behaviors may improve health outcomes in individuals prescribed these medications and in individuals who have recently had an overdose.”

“Addressing the challenges of substance abuse, including the emergence of new drugs and polysubstance use, is a complex task that requires a clear understanding of the magnitude of the problem and the burden it places on the population and the health care system,” Martins and Santaella-Tenorio said.

It is possible that the decline in cannabis and stimulant use among younger populations can be attributed to mobility restrictions during the COVID pandemic. The researchers noted that the decline in these overdose rates may also be related to changes in consumption patterns that are less likely to lead to overdose.

According to Martins and Santaella, survey data likely underestimate the prevalence of drug use, since the CNSSU is a household survey that excludes populations at high risk for drug use, i.e., homeless people and prisoners. In addition, overdoses not treated in health facilities are not included in the SIVIGILA data.

Over the past 30 years, Colombia has moved to a regulatory framework that focuses on human rights and public health in relation to substance use. This approach is in line with the guidelines of the United Nations Office on Drugs and Crime.

The findings highlight the need for additional prevention measures, including harm reduction and community programs, and improved access to treatment services that can reduce the risk of overdose in the population.

“Health surveillance systems are an important tool that can guide overdose prevention efforts in countries with limited data resources. Although this particular study focuses on Colombia, their surveillance system methodology can inform public health prevention efforts in other countries with limited resources,” Martins noted.