Mortality in adults with chronic non-cancer pain: a systematic review of observational studies
Creators: name: Richards, Georgia C.
name: Webb, Stephanie
name: Roberts, Antonia-Olivia
name: Scullion, Lauren Kate
Publisher: name: Open Science Framework
Year: 2023
Subjects: subject: Public Health
subject: Epidemiology
subject: Medicine and Health Sciences
subject: Clinical Epidemiology
subject: death
subject: systematic review
subject: chronic pain
subject: risk factors for death
subject: mortality
subject: observational studies
subject: chronic non cancer pain

description: Chronic pain is pain that persists or recurs for more than 3-months (1). It is estimated that 35% to 51% of adults in the UK experience chronic pain (2). In 2016, pain and pain-related diseases were graded as the main cause of disability and disease burden globally, with neck and lower back pain being the leading cause of disability (3). Not only is chronic pain a major burden on health systems, but it also impacts those from lower socioeconomic backgrounds more greatly, with those from less affluent areas experiencing more pain and more severe pain (4). Moreover, a systematic review showed that those with chronic pain suffer negative effects on their quality of life, and social, family, and occupational life (5). People with chronic pain may be offered various interventions which have varying levels of benefits and harms, including death. The National Institute for Health and Care Excellence (NICE) guidelines suggest assessing the person with chronic pain holistically and offering a range of management options including physical activity, psychological therapy, and acupuncture (6). Despite these recommendations, the use of analgesics, such as opioids, are often used, which provide minimal benefits for people with chronic non-cancer pain (7). Moreover, the use of opioids has also increased the risk of all-cause mortality in people with chronic pain (8). Surgery can also be offered for people with chronic pain. However, procedures are risky, and pain usually returns within six to 12 months (7,9). Therefore, understanding the causes of death in people with chronic pain since the changes in NICE guidelines will improve the evidence on the safety of treatment and management strategies for those living with chronic pain. Despite these data, systematic reviews on mortality and chronic pain are uncommon. In 2014, a systematic review of global studies was published (10). In this review, ten were included with four studies conducted in the UK. The review concluded that in people with chronic pain, there was a slight increase in mortality, and included mortalities associated with cancer (10). Moreover, the review included varying definitions of pain and did not explicitly focus on chronic pain. Since the 2014 review, cohort studies in people with chronic pain and mortality have been published (11,12), with Macfarlane et al. (2017) conducting a meta-analysis of the literature on mortality and chronic widespread pain including cancer-related mortalities (12). Therefore, an update-to-date systematic review on mortality and chronic noncancer pain is required to understand if the risk of mortality in a person with chronic noncancer pain. Currently, there are registered systematic reviews investigating mortality and spinal pain (13), and mortality and back pain (14). There are no reviews broadening the search to include all types of chronic noncancer pain, associated mortality, and risk factors worldwide. Therefore, this review aims to determine the prevalence and causes associated with death in people with chronic noncancer pain worldwide.