Opioid Use and Mental Health among Veterans of Iraq and Afghanistan

Veterans of the conflicts in Afghanistan (Operation Enduring Freedom [OEF]) and Iraq (Operation Iraqi Freedom [OIF]) who have sustained battlefield injuries have had a better chance of survival than veterans of earlier conflicts. This trend is facilitated by increasingly effective medical evacuation and battlefield medicine, as well as improvements in battlefield protective gear. These increased odds of survival, however, have resulted in greatly increased numbers of returning veterans with comorbid mental and physical health problems.

According to the Department of Veterans Affairs (VA), posttraumatic stress disorder (PTSD) is the most prevalent mental health disorder among veterans of these conflicts who use VA healthcare benefits. Pain has been the among the most significant and prevalent comorbid disorders associated with former soldiers, sailors, airmen, and marines with PTSD. Since 1994, the prescription of analgesic opioids has doubled; the abuse and misuse of these opioids has increased significantly, as well. There is a particularly high risk of opioid abuse or misuse among veterans due to the high cooccurrence of substance abuse disorders among veterans with PTSD.

The investigators wished to assess the effects of mental health disorders, particularly PTSD, on patterns of opioid prescription, associated risks, and adverse clinical outcomes such as accidents or overdose. For this retrospective cohort study [JAMA. 2012;307(9):940-947], the authors identified 291,205 veterans who entered VA health care between October 1, 2005, and December 31, 2008.  Patients in the main study population (n =141,029, 48.0%) were identified as Iraq and Afghanistan veterans who received a new non-cancer pain diagnosis within one year of VA entry. Each veteran was followed up for 1 additional year from initial pain diagnosis to evaluate whether he/she received an opioid prescription and whether he/she experienced an adverse clinical outcome during this one-year follow-up period.

Of the 141,029 veterans studied, 124,803 (88.5%) were male, 81,372 (57.7%) were >30 years of age, 131,594 (93.3%) were enlisted personnel, and 90,640 (64.3%) served in the Army. The majority (66%) had received ≥2 different pain diagnoses; 51% received at least 1 mental health diagnosis. A total of 19% received mental health diagnoses excluding PTSD and 32% received PTSD diagnoses with or without other mental health diagnoses.

Of the 141,029 veterans with pain diagnoses, 15,676 (11.1%) received prescription opioids for ≥20 consecutive days; 77% of these were prescribed by VA primary care clinicians. Compared with 6.5% of veterans without a mental health diagnosis, 17.8% (adjusted relative risk [RR], 2.58; 95% confidence interval [CI], 2.49-2.67) with PTSD and 11.7% (adjusted RR, 1.74; 95% CI, 1.67-1.82) with mental health diagnoses but not PTSD were significantly more likely to receive opioids for pain.

Compared with veterans without mental health diagnoses, those with PTSD who were prescribed opioids were significantly more likely to be in the highest quintile for dose (22.7% vs 15.9%; adjusted RR, 1.42; 95% CI, 1.31-1.54), receive ≥2 types of opioid concurrently (19.8% vs 10.7%; adjusted RR, 1.87; 95% CI, 1.70-2.06), receive concurrent sedative hypnotics (40.7% vs 7.6%; adjusted RR, 5.46; 95% CI, 4.91- 6.07), and obtain early opioid refills (33.8% vs 20.4%; adjusted RR, 1.64; 95% CI, 1.53-1.75). Those with PTSD compared with those with mental health diagnoses other than PTSD were significantly more likely to be prescribed opioids longer than the median duration of 2 months and were significantly more likely to receive opioids and sedative hypnotics concurrently. For all veterans, receiving prescription opioids (vs not) was associated with an increased risk of adverse clinical outcomes (9.5% vs 4.1%; RR, 2.33; 95% CI, 2.20-2.46), which was most pronounced in veterans with PTSD.