Association exists between cannabis use and schizophrenia




Using cannabis or cannabinoids can effectively treat chronic pain as well as ease some of the side effects of chemotherapy. However, there also seems to be substantial evidence of an association between cannabis use and the development of schizophrenia, more frequent bouts of bronchitis and an increased risk of motor vehicle crashes, according to a report.

Those conclusions come from a report released Jan. 12 and developed by the National Academies of Sciences, Engineering and Medicine.

The report, “The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research,” contains nearly 100 conclusions related to the health effects of cannabis and cannabinoid use. Cannabis refers to the plant known as marijuana. Cannabinoid refers to medications that contain the chemicals found in the plant.

The researchers examined existing evidence among more than 10,000 studies related to beneficial, harmful or benign effects of cannabis, then listed whether the evidence was conclusive, substantial, moderate, limited or nonexistent.

The researchers examined studies dealing with the use of cannabis in health situations including cancer, respiratory disease, immune function, mental health, heart disease and pregnancy, among others.

The report is one “of the most comprehensive studies of recent research on the health effects of recreational and therapeutic cannabis use,” since 1999, according to the National Academies of Sciences, Engineering and Medicine.

At the time of the study, 28 states and Washington D.C. had legalized cannabis for medicinal usage, Marie McCormick, chair of the committee on the health effects of marijuana, wrote in the report. Eight of those states and Washington D.C. have also legalized cannabis for recreational usage, she wrote, adding “there is a clear need to establish what is known and what needs to be known about the health effects of cannabis use.”

“Having good research is essential so that we know how best we can use it, what are the safest ways, and what are the real risks,” Staci Gruber, said in an online article published Jan. 13 in Business Insider. Gruber is an associate professor of psychiatry at Harvard Medical School and director of the Marijuana Investigations for Neuroscientific Discovery program at McLean Hospital.

Among the report’s conclusions are the following:

• Cannabis use before driving increases the risk of being involved in a motor vehicle accident.

• In adults with chemotherapy-induced nausea and vomiting, oral cannabinoids can reduce those side effects.

• Adults with chronic pain treated with cannabis or cannabinoids likely will experience significantly fewer symptoms.

• Short-term use of oral cannabinoids in adults with multiple sclerosis relieve some of the symptoms of the disease.

• Long-term cannabis smoking could lead to chronic bronchitis.

• Smoking cannabis during pregnancy is linked to lower infant birth weight.

• A statistical association exists between cannabis use and the development of schizophrenia or other psychoses, with the highest risk among the most frequent users.

• Cannabis use likely does not increase the chance for developing depression, anxiety and posttraumatic stress disorder. However, those diagnosed with bipolar disorders who use cannabis daily may experience worsening symptoms of the disorder.

• Moderate evidence shows no link between smoking marijuana and lung cancer.

• No clear evidence exists on whether cannabis use is linked to heart attack, stroke or diabetes.

The report noted that more study is needed, but that some barriers make it difficult to conduct research. For example, researchers have difficulties gaining access to the quantity, quality and type of cannabis product necessary to address specific research questions on the health effects of cannabis use. The researchers suggested more funding be provided by governmental agencies to continue studies.

Click here for more information on treating cancer pain.


About the author
Sallie Jimenez

Sallie Jimenez 

Sallie Jimenez, who is Content Manager for Healthcare, develops and edits content for OnCourse Learning’s Nurse.com blog, which covers industry news and trends in the nursing profession and healthcare. She also develops content for the OnCourse Learning/Nurse.com Digital Resource Guides. She has more than 22 years of healthcare journalism, content marketing and editing experience.

5 responses to “Association exists between cannabis use and schizophrenia”

  1. Sallie, this is a very misleading headline. The conclusion in the report is that ” a statistical association exists between cannabis use and the development of schizophrenia or other psychoses, with the highest risk among the most frequent users.” This is not at all the same as your title “Cannabis Use Leads to Schizophrenia”. That aside, thanks for the post and the write up on the report. Very interesting!

  2. As a nurse I am often asked if cannabis is helpful or harmful to the health of the pt. I work for the federal government and therefore cannot advocate the use of non-FDA approved therapies. I have stated that there are many health conditions that are greatly benefited by it’s use and if the pt feels that this is something they want to explore they need to talk to their doctor and research it more completely. All that aside, I have seen pt’s able to cope and manage pain and anxiety with the use of cannabis. Never smoked, but consumed through measured and deliberate amounts. When there is a pt with lung cancer metz to liver, kidney, bone and possibly brain the pain is insurmountable. The drugs used to treat the pain make a pt groggy and “out of it”, where as cannabis allows them the freedom from some of the pain and allows them the time with family and loved ones before they are gone. I have seen pt’s that have PTSD and cannot tolerate being in public, cannabis takes the edge off, offering an opportunity to work through the painful situations. My point is not every treatment is right for every pt. Whatever treatment plan the pt decided to go with needs to be researched and explored by the pt and health care professionals, not a plan that is given to the pt by the doctor and blindly followed. There is power in knowledge, and empowering pt’s is my job.

  3. I’m somewhat confused by the resistance to cannabis. Alcohol and tobacco are documented to cause extreme health and societal issues, yet they both are legal. Can you explain why these harmful substances are treated differently. Thank you

  4. I would like to know the future for newly retired RN of 40 years with critical care, ER,management and corporate nursing experience. I would like to keep hands in nursing but not in bedside care or home care. I realize a large amount of ambulatory clinics are utilizing Certified Medical Assistants in place of skill nursing in these settings.

Leave a Reply

Your email address will not be published. Required fields are marked *