A non-interventional retrospective study in England and Scotland estimating the economic burden of moderate-to-severe chronic pain due to osteoarthritis (OA) or chronic low back pain (CLBP)

Date of ISAC Approval: 
31/07/2019
Lay Summary: 
Osteoarthritis (OA) and chronic low back pain (CLBP) represent two of the most common chronic pain conditions worldwide. It is estimated that around 14 million people in England alone live with chronic pain. With the number of people experiencing chronic pain increasing with age, it is anticipated that chronic pain will become a greater problem for society in the UK as the population is getting older. Many forms of therapy exist for the treatment of pain for OA and CLBP patients, including drugs (analgesics, non-steroidal anti-inflammatory drugs, opioids), surgical/invasive procedures (e.g. total joint replacement, steroidal joint injections) and other interventions (e.g. physiotherapy, pain management programmes). Despite the wide range of approved therapies currently available to patients, therapies that are not recommended for the treatment of pain are being used due to the lack of alternative effective options. Therefore, a need exists for new, more effective treatments. The primary objective of this study is to estimate the healthcare services and associated costs to the NHS of treating moderate-to-severe chronic pain due to OA and/or CLBP in England and Scotland using anonymised NHS data. Results from this study may indicate that existing treatment options are not sufficient for managing patients' pain and will help to explore how a new and more effective treatment might be beneficial in the UK.
Technical Summary: 
Objectives: The primary objective of this study is to describe the total healthcare resource utilisation (HCRU) and direct healthcare costs associated with moderate-to-severe chronic pain due to osteoarthritis (OA) or chronic lower back pain (CLBP) in England and, where feasible, Scotland. Methods: This study will be a retrospective, longitudinal cohort study, with comparator group, of OA and/or CLBP patients indexed on a moderate-to-severe chronic pain event between December 2009 and November 2018, inclusive. Moderate-to-severe chronic pain events will include pain-related referrals/visits to secondary care (rheumatology, orthopaedics, pain management or Accident and Emergency [A&E]), prescriptions of pain medications (opioids or non-steroidal anti-inflammatory drugs) and surgical procedures for the treatment of pain in OA and/or CLBP. Each patient within the study cohort (cases) will be matched to at least one general population control with no record of an OA or CLBP diagnosis. For this study, data within the Clinical Practice Research Datalink will be linked to Hospital Episode Statistics (specifically, inpatient, outpatient and A&E data) to comprehensively assess HCRU and associated direct healthcare costs, and the Mental Health Data Set to explore aspects of social care utilised within the study cohort. Data analysis: This study will be predominantly descriptive in nature, with all outcomes reported using appropriate descriptive statistics, and outcomes compared statistically between cases and controls, where applicable, using standard unpaired statistical tests. In addition, generalised linear models will be constructed to assess potential predictors of weak and strong opioid use, and higher direct healthcare costs, whilst Kaplan-Meier estimates will be calculated to assess time to first OA/CLBP-related surgery.
Health Outcomes to be Measured: 
GP appointments (all-cause and OA/CLBP-related); Outpatient visits (all-cause and OA/CLBP-related); Hospitalisations (all-cause and OA/CLBP-related); A&E visits (all-cause and OA/CLBP-related); Direct healthcare costs (all-cause and OA/CLBP-related); Demographics (age, sex, ethnicity, region); Clinical characteristics (body mass index, weight, comorbidities, age at diagnosis); Treatment patterns (drug/class prescribed, treatment dynamics, number of lines of therapy received and adverse events of treatments); Incidence of OA; Incidence of CLBP; Prevalence of OA; Prevalence of CLBP; OA/CLBP-related surgery (time to surgery).
Collaborators: 

Mr Christoph Lohan - Chief Investigator - Pfizer Ltd - UK
Dr Birol Emir - Collaborator - Pfizer Ltd - UK
Mr Daniel Bluff - Collaborator - Not from an Organisation
Professor David Andrew Walsh - Collaborator - University of Nottingham
Ms Deepa Malhotra - Collaborator - Pfizer Ltd - UK
Mr Greg Coates - Collaborator - Pfizer Ltd - UK
Ms Hannah Haswell - Collaborator - Pfizer Ltd - UK
Jessalyn Kemp - Collaborator - Not from an Organisation
Ms Liz Hennessy - Collaborator - Adelphi Real World
Robert Wood - Corresponding Applicant - Adelphi Real World
Shuk-Li Collings - Collaborator - Pfizer Ltd - UK

Linkages: 
HES A&E;HES Admitted;HES Outpatient;Mental Health