Colorado releases new report on potential health effects of marijuana |

Colorado releases new report on potential health effects of marijuana

Sawyer D'Argonne
Summit Daily
Marijuana plants ready to be harvested at a grow house in Denver.

Coloradans are consuming more marijuana than ever, and as research into potential health effects continues to take shape, concerns are being raised.

The Colorado Department of Public Health & Environment (CDPHE) recently released a new study: “Monitoring Health Concerns Related to Marijuana in Colorado: 2018.” The report, mandated every two years in the Colorado Revised Statutes, helps to provide insights into marijuana usage patterns among Coloradans, emerging research into the drug’s effects and data surrounding recorded health effects associated the substance.


Relying primarily on self-reported information from six separate data sources — including the National Survey on Drug Use and Health, the Healthy Kids Colorado Survey and the Behavioral Risk Factor Surveillance System — the Marijuana Health Monitoring and Research Program at CDPHE was able to determine significant changes in usage patterns among Coloradans.

The report revealed that usage rates among adults continue to rise. Adults who have used marijuana in the past 30 days of taking a survey increased from 13.6 percent in 2016 to 15.5 percent in 2017, considerably higher than the national average of 9.5 percent. While usage is highest for adults aged 18-25 (29.2 percent used over the last 30 days), there were increases among adults aged 26-34 (19.4 percent in 2016 to 26.4 percent in 2017) and over 65 (4.2 percent to 5.6 percent). Of note, adult usage remained considerably higher in men (19.8 percent) than women (11.2 percent). Individuals who identified in the LGBTQ community also reported significantly higher usage rates (34.7 percent) than those who identified as heterosexual (14.5).

Daily or nearly daily usage among adults also increased from 6.4 percent in 2016 to 7.6 percent in 2017, and the data suggests that marijuana users are increasingly more willing to experiment with different methods of consumption. While more than 84 percent of users reported smoking marijuana in the last 30 days, 50 percent reported multiple methods of use including taking edibles (40.4 percent), vaporizing (29.1 percent) and dabbing (21.1 percent).

While adult usage continues to grow, the same can’t be said for adolescents. About 19 percent of Colorado high school students and 5.2 percent of middle schoolers reported using marijuana 30 days before the survey, a steady rate compared to 2016 and consistent with the national average.

Despite relatively inspiring data surrounding adolescent usage, the report still notes serious concerns regarding marijuana in homes with children. In 2017, an estimated 11.2 percent of Colorado homes with children reported marijuana being present, an increase from just 6.9 percent in 2016. The majority (77 percent) reported safely storing their marijuana where children couldn’t get it, though CDPHE estimates there are more than 23,000 homes in the state with children aged 1-14 where the drug is not safely stored. About 5.5 percent of homes with children reported marijuana being smoked inside, meaning an estimated 32,800 homes contained possible secondhand marijuana smoke.

The data also suggests an education and age discrepancy between women using marijuana during pregnancy. Pregnant women aged 15-19 had a much higher usage rate (13.3 percent) than women aged 25-34 (5.3 percent) and 35 and older (3.4 percent). Additionally, women with less than 12 years of education (10.4 percent) consumed marijuana during pregnancy at a much higher rate than women with more than 12 years of education (4.8 percent)


As part of the report, the Retail Marijuana Public Health Advisory Committee reviewed scientific literature on the health effects of marijuana use, breaking down which research areas contain limited to substantial evidence, along with the areas with significant gaps in research.

The review showed that marijuana use during pregnancy and breastfeeding might show a number of effects on the child in the months or years after birth, including decreased growth and impaired cognitive function and attention. Similarly, the report notes that adolescent and young adult users are more likely to experience psychotic symptoms as adults and suffer from deficits in learning.

According to the report, there’s strong evidence linking daily marijuana use with cyclic vomiting, chronic bronchitis and other respiratory issues. Strong evidence also shows that daily users are more likely to have impaired memory after quitting, can experience withdrawal and become addicted to the substance.

The review also notes a number of gaps in research, including on the full effects of consumption while pregnant, long-term health effects of consumption, research on frequent users’ tolerance and impairment while driving, the effects of marijuana in interaction with other drugs, marijuana’s links to cancer and more.


Data in the report from the Rocky Mountain Poison and Drug Center and the Colorado Hospital Association also helps to shed light on the immediate health effects of marijuana in Colorado.

Overall, the number of individuals reporting marijuana exposure to poison control has been stable since legalization in 2014, though the number of children unintentionally exposed to the substance continues to creep upwards from 40 in 2016 to 50 in 2017. More than 65 percent of all unintentional exposures in children ages 0-8 were caused by edibles.

There was also a small increase in emergency department visits (measured by marijuana-related billing codes) from 1,065 per 100,000 visits in 2016, compared with 1,139 per 100,000 visits in 2017. Despite the increase, hospitalizations related to marijuana decreased from 3,517 per 100,000 in 2016 to 3,439 per 100,000 in 2017.

“Sound science guides our efforts to protect Coloradans’ health,” said Dr. Tista Ghosh, interim chief medical officer at CDPHE in a statement. “It’s critical we continue to monitor use in all populations and work to minimize harms that could result from a variety of causes including unintended poisoning, unsafe driving, and mental health issues that may be associated with long-term, habitual use.”