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

According to a study by Columbia University's Mailman School of Public Health, overdose rates in Colombia involving illicit opioids, hallucinogens, stimulants and sedative psychotropic drugs rose sharply between 2018 and 2021, mainly caused by overdoses among young women. The number of drug overdoses increased by 356% between 2010 and 2021, from 8.5 to 40.5 per 100,000 people. The results were published in the American Journal of Public Health.

The study is the first to describe national trends in overdose rates, including prescription and illicit substances and alcohol, across different populations in Colombia.

“In particular, the pandemic has contributed to higher levels of stress and mental health problems such as depression and anxiety in Colombia, similar to other countries,” said Silvia Martins, MD, Ph.D., professor of epidemiology at the Columbia Mailman School and senior author of the study. “Higher prescription rates and use of tranquilizers/sedatives/antidepressants in Colombia during the pandemic due to experiences of higher levels of anxiety, sadness, and sleep disturbances may have led to medication overuse. 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 in the country has increased over the past three decades for most substances. There was only a slight 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 sociodemographic characteristics, researchers also used data from SIVIGILA – a national public health surveillance system from 2010 to 2021, a mandatory reporting system for detecting health events.

The SIVIGILA data included 127,087 substance-related overdoses among persons aged 10 years and older. 54% of the persons were male, 75% were persons aged 10 to 34 years, 72% had at least a high school education or higher, and 51% and 38%, respectively, were persons who either contributed to the health system or received 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 determined the most common combinations of several substances during the entire study period and the number of overdoses caused by these combinations.

The most commonly reported substances 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 mostly due to prescription opioids (74%).

Tranquilizers/sedatives/antidepressants and opioid overdose rates increased during the study period and increased even more rapidly after 2018. Cannabis and stimulant overdoses also increased until 2017 but declined thereafter. Among women, the largest increase in overdose rates was for tranquillizers/sedatives/antidepressants, which increased even more rapidly from 2018 to 2021 (from 12 to 33 per 100,000).

“To improve harm reduction interventions and strategies, more research is needed on risk factors, motives for use, and sources of these drugs,” notes Julian Santaella-Tenorio, DrPH, professor at the Universidad Pontificia Javeriana in Cali, Colombia, former DrPH student at Columbia University, and lead author of the study.

“We also believe that suicide risk screening and access to complementary mental health care for suicidal thoughts or behavior can improve the health of people prescribed these medications, as well as people who have recently overdosed.”

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

The decline in cannabis and stimulant use among younger people may be due to mobility restrictions during the COVID pandemic, but the reduction in overdose rates may also be related to changes in consumption patterns that are less likely to lead to overdoses, the researchers said.

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

Over the past thirty years, Colombia has transitioned to a drug regulatory framework that is guided by human rights and public health and complies with the guidelines of the United Nations Office on Drugs and Crime.

The findings suggest that additional prevention efforts are needed, including harm reduction and community-based programs, as well as increased access to treatment services that can reduce the risk of overdose in the population.

“Health surveillance systems are an important tool to support overdose prevention efforts in countries with limited data resources. While this particular study focuses on Colombia, the methodology of their surveillance systems can provide information for public health prevention efforts in other resource-poor countries,” Martins noted.