Chronic use of prescribed painkillers was found to increase the risk of depression, according to a new Saint Louis University study.
Opioid analgesics, or prescription-based narcotic pain killers are known to reduce pain but previous studies have linked excess use of such medication to adverse effects on a person's health. In a new study, researchers from Saint Louis University added another health issue linked to pain killers.
Researchers found that chronic use of prescribed painkillers increased the risk of depression. During the study, they noted that patients who too opioids for 180 days or longer were at a 53 percent increased risk of developing depression, and those using opioids for 90-180 days were at a 25 percent increased risk compared to patients who never took opioids for longer than 1-89 days.
"These findings suggest that the longer one is exposed to opioid analgesics, the greater is their risk of developing depression," said Jeffrey Scherrer, Ph.D. associate professor of family and community medicine at Saint Louis University and principle investigator of the study. "Opioids have long been known to allay pain and suffering, but reports of adverse effects are abundant and continue to emerge."
Though Scherrer wasn't able to detect the exact mechanism behind the link between painkiller usage and depression, he found that there were many factors that contributed to it. One factor was the opioid reset the brains 'reward pathway' to a higher level. This led to an elevation of the threshold for a person's ability to experience pleasure from natural rewards such as a food or sexual activity. Another factor was related to taking such mediation for long after the pain had subsided which resulted in side effects like adrenal, testosterone and vitamin D deficiencies and glucose dysregulation.
"Preliminary evidence suggests that if you can keep your daily dose low, you may be at lower risk for depression," he said. "Even though the risk is not huge, there is enough exposure that we may have a public health problem."
Statistics show that one in every four Americans, accounting for 26.2 percent of the country's population, suffers from mental disorders, depression being the most common condition. Major Depressive Disorder is the leading cause of disability in the U.S. for ages ranging from 15-44, affecting approximately 14.8 million American adults.
