Schizophrenia and Cannabis-Use Found to be Drivers of Brain Aging
Researchers from John Hopkins, University of California, Google and others conducted the largest known brain imaging study to determine the drivers of brain aging. More than 30,000 individuals from 9 months to 105 years old had their brains scanned in hopes of identifying patterns of aging.
Understanding the influence of aging on the brain remains a challenge in determining its role as a risk factor for diseases like Alzheimer’s. The purpose of the study was to investigate how common disorders such as ADHD, and alcohol use accelerate this aging of the brain.
Using SPECT (single photon emission computed tomography) imaging, scans of patients brains from multi-site psychiatric clinics were examined. This technology evaluates cerebral blood flow in the brain that is reduced in various disorders. Simply, it is a type of nuclear imaging test that shows how blood flows to tissues and organs.
Scans were taken when patients were at rest (not doing anything) and when they were preforming a concentration task – so in total, there were over 60,000 brain scans! Patients had many different psychiatric disorders including schizophrenia, bipolar disorder and anxiety.
128 brain regions were studied to predict chronological age of the patient and then the estimated age was determined from the scans. When the scan predicted an older age than the actual age of the patient, that’s when accelerated aging has taken place.
The overall results of this massive study, published on August 3rd in the Journal of Alzheimer’s Disease, show that a number of brain disorders actually predicted accelerated aging. Schizophrenia showed an average of 4 years of premature aging, bipolar disorder, 1.6 years, and ADHD, 1.4. Interestingly, cannabis use was also high up on the list at 2.8 years of accelerated aging.
The lead author of the study, Daniel G. Amen, MD, said that “the cannabis abuse finding was especially important, as our culture is starting to see marijuana as an innocuous substance. This study should give us pause about it.”
“Based on one of the largest brain imaging studies ever done, we can now track common disorders and behaviors that prematurely age the brain. Better treatment of these disorders can slow or even halt the process of brain aging. The cannabis abuse finding was especially important, as our culture is starting to see marijuana as an innocuous substance. This study should give us pause about it.” – Daniel G. Amen, MD
Another important aspect of this study is that the results indicate that we can predict someone’s age based on patterns of their cerebral blood flow. The authors also state that these kinds of larger studies are essential to answer questions about how to maintain brain structure and function during aging.