- Prescribed opioids, especially higher-dose and immunosuppressive opioids, are associated with increased CAP risk among persons with and without HIV.
- To mitigate the risk, doctors should reduce opioids prescription, especially immunosuppressive ones, or prescribe lower doses.
- The risk of pneumonia can be mitigated through vaccination against pneumonia and promoting smoking cessation.
Some opioids (including codeine, fentanyl, and morphine) are known immunosuppressants; however, the association of prescribed opioids with clinically relevant immune-related outcomes is understudied, especially among people living with HIV.
This nested case-control study used data from patients in the Veterans Aging Cohort Study (VACS) from January 1, 2000, through December 31, 2012. Patients with community-acquired pneumonia (CAP) requiring hospitalization (n = 4,246) were matched 1:5 with control individuals without CAP (n = 21,146) by age, sex, ethnicity, length of observation, and HIV status (98.9% male; mean age 55 ± 10 years).
Prescribed opioid exposure during the 12 months before the index date was characterized by a composite variable based on timing (none, past, or current); low (50mg) median morphine equivalent daily dose; and opioid immunosuppressive properties (yes vs unknown or no).
Prescribed opioids were independently associated with CAP in patients living with and without HIV. The risk for CAP increased with higher opioid doses, prescription duration and opioids with known immunosuppressive properties. Individuals with HIV tended to be more likely to develop pneumonia even at low doses of opioids and especially with immunosuppressive opioids.
Prescription opioids can impact the body's defences against pneumonia in different ways including by suppressing cough, respiration, and inhibit mucus secretion.
The study, published in JAMA Internal Medicine, is consistent with the hypothesis that opioids have effects on the immune system. Efforts to minimize prescribed opioid use, especially in patients living with HIV, and curtailing the use of higher doses, or immunosuppressive opioids, may help mitigate this risk.
The study also underscores the need for opioid prescribers to take action, to minimize the risk of pneumonia, by promoting both vaccination against pneumonia and smoking cessation.