Factors predicting outcomes from chronic pain management interventions

Abstract

Chronic pain is the leading cause of years lost to disability worldwide, by a large margin, affecting 20-34% of the world's population. Chronic pain is the target for an increasing number of invasive and expensive treatments, supported by different levels of evidence. At a time when personalised medicine, driven in part by the growth of artificial intelligence, is surging, a scoping review on the factors that affect pain outcomes for procedural interventions is needed. A scoping review is important because placebo controlled trials for the most commonly used treatments consistently show small-to-moderate effect sizes of <0.5 that are often overshadowed by the placebo effect. In this article, personal characteristics, and social and clinical factors that influence surgical and non-surgical procedure pain and functional outcomes are reviewed, their intersectionality is briefly explored, and the evidence base for how dealing with these factors can influence outcomes is outlined.

Keywords: Anxiety disorders; Back pain; Neurosurgery; Pain; Pain management.

Figure 1. Intersectionality of factors associated with interventional treatment outcome. Examples of factors are: obesity and smoking; diffuse pain and psychiatric variables; dissatisfaction with current employment causing subconscious secondary gain; and association between prescription opioid use and substance misuse. The radial network graph shows connections between factors, with relative strength of relations represented by the thickness of the lines (binary system where a thin line signifies a weak correlation and a thicker line signifies a stronger one). Figure images based on original drawings by Seffrah J Cohen, Brandeis University