Opioids can impair the immune system and lead to illnesses such as meningitis and pneumonia.

Taking prescription opioids may significantly increase a person’s risk of developing dangerous infections that could lead to meningitis and pneumonia, according to a new study out today.

Doctors have known for years that prescription opioids can suppress the immune system. But they weren’t sure exactly which infections these patients were at increased risk of contracting.

In a new study published today in the Annals of Internal Medicine, researchers from Vanderbilt University found evidence that people taking prescription opioids are more at risk for developing certain dangerous bacterial infections.

The researchers used the Tennessee Medicaid database and the Active Bacterial Core surveillance system to see what links they could find between opioid use and bacterial disease.

Andrew Wiese, PhD, MPH, a postdoctoral research fellow in the department of health policy at Vanderbilt University School of Medicine and lead author of the study, said researchers wanted to better understand the side effects of prescription opioid use.

Studies “have shown that certain opioids can cause immunosuppression,” he said. “They can disrupt the innate immune system.”

Wiese and his co-authors looked at 1,233 patients with invasive pneumococcal disease (IPD) and compared them to 24,399 control participants.

They found those with IPD were more likely to be using a prescription opioid than the control group. More than 25 percent of those with IPD were on opioids, compared to 14 percent of the control group.

They also found that patients with IPD were more likely to be using long-acting, high-potency opioids.

Pneumococcal disease is a bacterial infection caused by Streptococcus pneumoniae bacteria. In invasive cases, the disease can lead to serious complications, such as meningitis, invasive pneumonia, or bacteremia, the spreading of bacteria into the bloodstream.

Wiese said he hoped the research would help both doctors and patients be better informed about prescription opioid risks.

“I think for both providers who prescribe opioids and for patients that receive opioids, this is more information that they should consider when making the decision to prescribe or receive opioids,” Wiese said.

Dr. Amy Edwards, an infectious disease physician at the University Hospitals Cleveland Medical Center, said that doctors still don’t have a lot of options in terms of pain reliever medication.

“We’re basically limited to opioids and Tylenol. There’s not a lot in between,” she told Healthline. “It does tie our hands to a certain extent that there’s not a lot of variety out there.”

While she said that study findings weren’t surprising, she thought they added to a growing body of research on how opioids affect the immune system. She said she hoped in the future that research could clarify which opioids are less likely to impact the immune system.

“One thing that I think would be very interesting… would be, are there opioids that do this more and ones that do this less?” she said.

She pointed out that clear information on which opioids are safer could be key for doctors treating intubated patients in an ICU setting.

Dr. Alan Mensch, senior vice president of medical affairs at Northwell Health’s Plainview and Syosset Hospitals in New York, said these findings could be especially worrying in light of the ongoing opioid crisis.

An explosion of opioid use, especially illicit opioid use, in recent years has led to tens of thousands of fatal overdoses annually.

The Centers for Disease Control and Prevention estimates there are 115 fatal overdoses from opioids every day.

Mensch pointed out these IV drug users may be especially immunocompromised and at risk for these complications.

“I don’t know if anyone has looked at it, but it would be an interesting thing to look at,” he said. “We should be more concerned about [this] community… IV drug users getting more infections,” he told Healthline.