Focus on Research November 2013

Focus on Research:

Trajectory of Adverse Events and Analgesia with Opioids in Older Adults” (TAANGO)

By Rick Deyo, MD

Rick Deyo, MD, has extensive experience in treating and studying chronic back pain. His recent interest is finding new evidence for treating chronic pain in older populations, maximizing efficacy while minimizing negative effects. The NIH-funded pilot study, "Trajectory of Adverse Events and Analgesia with Opioids in Older Adults" (TAANGO), aims to demonstrate opioid prescribing patterns, analgesic effects, and adverse events in patients 55 and older with chronic musculoskeletal pain.

Deyo is the PI; David Buckley, MD, MPH, is a co-investigator and Oregon Rural Practice-based Research Network (ORPRN) has recruited clinics and patients, conducted enrollment and follow-up, and is managing the data.

research chartOpioid prescribing for chronic non-cancer pain has increased dramatically over the past 15 years, and current expert guidelines recommend treating pain in older adults with opioids rather than non-steroidal anti-inflammatory drugs. However, opioid use is controversial due to a lack of data on the trajectory of analgesia or adverse effects with long-term use. Long-term adverse events – aside from dependence - may include a risk of overdose, hypogonadism, falls and fractures, cognitive impairment, depression, sleep disturbance and sexual dysfunction.

A flurry of recent studies reveal concern about the safety risks of opiate use among older adults, including the potential for non-significant reduction in pain, increased pain intensity, falls and fractures, traffic accidents and multiple medication interactions. These risks must be weighed against the analgesic benefits of opiate therapy. Additionally, few studies have followed subjects for more than 16 weeks.

As a pilot project, TAANGO's aims are:

1. To enroll adequate numbers of patients 55 and older with chronic musculoskeletal pain from rural practices and demonstrate success in obtaining high rates of follow up; 

2. To estimate rates of initiating opioid therapy in this older population, and tentative predictors of long term use (such as pain severity, comorbidity, prior opioid therapy, use of other controlled substances, smoking, and mood disorders); and

3.  To determine the trajectory of analgesia and neuropsychological adverse effects prior to opioid therapy and during the year following initiation of opioid therapy.

The team hypothesized that initial analgesic benefit would wane as drug tolerance occurs, and that opioids would be associated with new or exacerbated neuropsychological events that increase with duration of therapy.

TAANGO is establishing feasible research procedures and providing data to estimate the incidence of long-term opioid initiation among older patients with chronic non-cancer pain.The team is looking for predictors of long-term opioid use, and identifying early neuropsychological effects of opioid therapy.

Over 200 subjects from five practices are now enrolled, and follow-up occurs every three months for 12 months. Follow-ups are completed in person or by phone.

The study uses PROMIS (Patient Reported Outcomes Measurement Information System) instruments that measure depression, fatigue, anxiety, sleep quality, physical function, memory, concentration and pain interference. Other data collection includes pain history, pain intensity, new pain complaints, work status, disability compensation status, cognitive status and pain medications. In addition, sexual functioning questions from the Medical Outcomes Study and questions on falls and fractures from Osteoporotic Fractures in Men Study are collected.

Enrollment is complete and data collection continuing. The investigators will prepare manuscripts related to some of the novel measures, and evaluate the emerging data to assess the feasibility of a larger scale cohort study.

Deyo's ultimate goal is to conduct a larger, multi-site prospective cohort study of opioid prescribing patterns, analgesic effects, and adverse effects among older adults.Such a study would include more subjects and longer follow-up, to address unanswered but clinically important questions.