A new study says there is no evidence that suggests an association between current or previous marijuana use and kidney function.
For the study published in The American Journal of Medicine, scientists analyzed a nationally representative sample of nearly 14,000 predominantly healthy adults aged 18-59 years living in the US who participated in the National Health and Nutrition Examination Survey from 2007 to 2014. Participants used an audio computer-assisted self-interview system to answer several questions.
Questionnaires were administered at a mobile examination center. Participants were classified as never users, past users, and current users of marijuana. Nearly 5,500 users said they had smoked marijuana at least once, but not in the past 30 days, and over 2,000 users had smoked marijuana at least once within the last 30 days. Serum creatinine concentration was measured after blood collection at the mobile examination center.
The investigators did not find any association between current or past marijuana use and impaired kidney function. There was no statistically significant association between history of marijuana use and the likelihood of developing stage 2 or greater chronic kidney disease. Likewise, they did not observe a statistically significant association between the history of marijuana use and the incidence of microalbuminuria, a moderate increase in the level of urine albumin and a marker of kidney disease.
Under US Federal law it is illegal to possess, use, buy, sell, or cultivate marijuana, although it is legal in some US states. As of January 2018, medical marijuana is legal in 30 states and the District of Columbia (DC); in eight states and DC, it is also legal for recreational use. Other states have taken steps to decriminalize marijuana to some degree.