Cannabis tied to serious complications in type 1 diabetes

People with type 1 diabetes may be more than twice as likely to develop potentially fatal complications when they use cannabis somewhat regularly than when they avoid the drug or rarely indulge, a study suggests.

Researchers surveyed 932 adults with type 1 diabetes about alcohol, smoking and substance use. They assigned each person a cannabis use score ranging from 0 for no use at all to 33 for the highest exposure to the drug.

Most participants - 871 - had little or no risk from cannabis exposure, with cannabis use scores of 0 to 3. Another 61 people were considered to have moderate risk from cannabis exposure, with cannabis use scores of 4 to 26.

Compared to low-risk individuals, people with moderate risk were 2.5 times more likely to experience ketoacidosis, a serious complication of diabetes that develops when blood sugar is elevated for too long and the body produces high levels of acids known as ketones. Left untreated, ketoacidosis can lead to severe dehydration, swelling in the brain, coma and death.

“Cannabis is a known addictive substance, and this potentially problematic aspect of cannabis use should be assessed in patients with type 1 diabetes,” study leader Gregory Kinney of the Colorado School of Public Health, University of Colorado Anschutz Medical Campus in Aurora and colleagues write.

Cannabis is the most commonly used illicit drug in the U.S., and recent legislation has made cannabis legal for either medical or recreational use in more than half of states, Kinney and colleagues note in Diabetes Care.

In a separate paper published recently in JAMA Internal Medicine, researchers involved in the current study reported similar findings, but only in patients from a single medical center in Colorado, where medical and recreational cannabis use is legal. The current study involved diabetes patients at 69 sites.

Moderate risk cannabis users in the current study tended to be younger, and more of them were male, compared to people who rarely if ever used the drug.

Moderate-risk individuals also had less education on average, had been diagnosed with type 1 diabetes at a younger age, and had poorer control of their blood sugar levels than people who rarely, if ever used the drug.

One limitation of the current study is that researchers relied on participants to accurately report any cannabis use, even when they lived in states where the drug is illegal. Researchers also lacked data on how well patients managed their diabetes or followed prescribed insulin treatment regiments.

Some previous research suggests that for people with type 2 diabetes - the more common form linked to obesity - cannabis may make it easier to maintain lower blood sugar levels. But less is known about the impact of cannabis on people like those in this study, who had type 1 diabetes, the less common form that typically develops in childhood and is caused by a breakdown in the body’s immune system.