Long-Term Painkiller Use Tied to Depression

People who take prescription opioids for longer than a month are more likely to develop depression, according to a new study from St. Louis University.

Researchers looked at data from three large groups totaling more than 100,000 people who started taking opioids around the time the study started. Their ages ranged from 18 to 80. None had depression at the start of the study, and the team followed up with the participants for seven to 10 years.

They found that 12 percent of the nearly 71,000 people in the first group, 9 percent of the nearly 14,000 people in the second group and 11 percent of the nearly 23,000 people in the third group had developed depression during the study period. And the longer that people took the opioids, the greater their risk of depression.

For example, in the group of 71,000 people, 11.6 percent of those who used opioids for one day to one month developed depression, compared with 13.6 percent of those who used opioids for one to three months and 14.4 percent of those who used the drugs for longer than three months.

In the group of 14,000 people, 8.4 percent of those who used opioids for one day to one month developed depression, compared with 10.6 percent of those who used opioids for one to three months and 19 percent of those who used the drugs for longer than three months.

The opioids included in the study were codeine, fentanyl, hydrocodone, hydromorphone, levorphanol, meperidine, oxycodone, oxymorphone, morphine and pentazocine.

It is not clear why the long-term use of opioids is linked to a greater risk of depression, but it may have something to do with lowered levels of testosterone.

Almost 259 million prescriptions were written for opioids in 2012, which is more than enough to give every American adult their own bottle of pills, according to the Centers for Disease Control and Prevention. In 2014, prescription pain relievers were linked to nearly 19,000 overdose deaths.

Don't miss this week's Slice of History: Prohibition Kicks In.

Sourced from: Live Science, Long-Term Opioid Use Linked to Depression