Cost-effectiveness of osteoporotic fracture risk assessment in people with intellectual disabilities

Date of Approval
Application Number
21_000433
Technical Summary

Unpublished results from our previous study (ISAC Protocol 18_186R) in CPRD Gold linked to HES show higher incidence of major osteoporotic (MOP) fractures (vertebra, shoulder, wrist, hip) and of hip fracture in adults with intellectual disabilities [ID] (n= 27706) compared to age and sex matched adults without ID (n= 139033).
We found that the current fracture risk calculator (QFracture) underestimated risk in ID patients.
We developed a risk score (IDFracture) estimating the 10-year risk of MOP and of hip fracture for ID adults 30-79 years old.
Aims
Validate IDFracture in the Aurum database
Determine the most cost-effective risk assessment method for MOP and for hip fractures in ID adults
Objective
Inform policy for osteoporotic fracture risk assessment
Outcomes
Incidence of MOP and of hip fracture within 10-years of the index date
Cost-effectiveness of 3 different strategies to determine risk of MOP and of hip fracture
Methods
Validation of IDFracture risk scores in the Aurum database with full linkage to HES and IMD datasets (to ensure complete capture of events and covariates).
For cost-effectiveness analyses we will use the subset aged 40-79 years.
We will use a Markov model with an annual transition cycle projecting life-long incidence of fractures and death. The model will be run assuming three strategies:

• Current strategy, using QFracture for risk calculation
• Risk assessment by IDFracture in all patients from age 40 years, with bone mineral density scan (DXA) in those in the region of an intervention threshold.
• DXA in all patients from age 40 (follow up according to result)

For each strategy, total lifetime costs and outcomes plus incremental cost-effectiveness ratio (ICER) will be calculated against the next most effective strategy. Main analyses will be done from NHS perspective. Impact of fracture on health-related quality of life will be taken from the literature.

Health Outcomes to be Measured

Major osteoporotic fracture, hip fracture within 10-years of index date.
Cost-effectiveness of each of the following strategies to estimate risk of MOP and of hip fracture
• Current strategy as recommended by the National Institute for Health and Care Excellence (NICE) using QFracture for risk score calculation (1-3)
• Risk assessment by IDFracture (4) in all patients from age 40 years, with bone mineral density scan (DXA) in those in the region of an intervention threshold (1, 5)
• To perform DXA in all patients from age 40

Collaborators

Valeria Frighi - Chief Investigator - University of Oxford
Valeria Frighi - Corresponding Applicant - University of Oxford
Felix Achana - Collaborator - University of Oxford
Gary Collins - Collaborator - University of Oxford
Jan Blair - Collaborator - Dimensions (UK) Ltd
Margaret Smith - Collaborator - University of Oxford
May Ee Png - Collaborator - University of Oxford
Stavros Petrou - Collaborator - University of Oxford
Tim Holt - Collaborator - University of Oxford
Timothy Andrews - Collaborator - Oxford Health NHS Foundation Trust

Linkages

HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation