People with intellectual disabilities (ID), namely those with Down syndrome (DS) and other conditions of intellectual impairment, have a higher rate of fracture and a younger age at fracture than the rest of the population. In the most recent and comprehensive studies, completed by our research group in the CPRD linked to the Hospital Episode Statistics database, we found that
1) The difference between people with ID and without ID was particularly marked for femoral fracture (FF), both in children and adults, and for hip fracture (HF) in adults
2) Adults with DS had a risk of HF almost twice as high than other people with ID
Femoral fractures, of which hip fractures are the largest subtype, are particularly severe fractures for the individual as they almost invariably require hospitalisation, surgery, and extensive rehabilitation. Moreover, FF can be a manifestation of osteoporosis, hence of a generalised tendency to fracture. We wish to understand better the characteristics of people with ID who sustain FF and the factors that put them at risk. In this study, we aim to investigate the incidence of FF in people with ID in relation to potential risk factors, namely causes of ID (e.g. DS, other syndromes) and frequently associated disorders (e.g. epilepsy, cerebral palsy). Incidence of HF will be a secondary aim.
The overarching objective of our study is to provide the scientific evidence on which a prevention strategy for femoral fracture in people with intellectual disabilities could be designed in the future.
Femoral fractures (FF), of which hip fractures (HF) are the largest subtype, are particularly severe fractures as they almost invariably require hospitalisation, surgery, and extensive rehabilitation. Moreover, FF can be a manifestation of osteoporosis. In our previous studies in the CPRD Gold and Aurum databases linked to the to the Hospital Episode Statistics (HES) database we found much higher rates of such fractures in people with intellectual disabilities (ID) compared to an age and sex matched population. Also, FF represented 3.9% and 11.2% of all fractures in children and adults with ID compared to 1.3% and 5.9% in children and adults without ID.
In this study, we aim to investigate the incidence of FF in people with ID in relation to potential risk factors, namely causes of ID (e.g. Down Syndrome, other syndromes) and frequent comorbidities (e.g. epilepsy, cerebral palsy). Incidence of HF will be a secondary outcome.
We will create three cohorts of people with ID: 1-17, 18-29 and ≥ 30 years of age at entry. We will calculate frequencies of risk factors in each of those cohorts for people who do and don’t develop FF. We will also estimate FF rates in people with/without each risk factor, and we will estimate hazard ratios using Cox proportional hazards regression. We will do the latter analyses in two cohorts by combining the two younger cohorts. As these are exploratory analyses we will estimate crude statistics and statistics adjusted for age and gender. We will select the ID population from the Aurum database. We will use the linked HES database for comprehensive capture of fracture events, the Index of Multiple Deprivation and the Ethnicity Record for description of the population and the Pregnancy Register to exclude diagnoses of ID made within the setting of antenatal screening.
Primary: Incidence of femoral fracture
Secondary: Incidence of hip fracture
Margaret Smith - Chief Investigator - University of Oxford
Margaret Smith - Corresponding Applicant - University of Oxford
Cynthia Wright Drakesmith - Collaborator - University of Oxford
Gary Collins - Collaborator - University of Oxford
helen stewart - Collaborator - Oxford University Hospitals NHS Foundation Trust
Jan Blair - Collaborator - Dimensions (UK) Ltd
Katja Maurer - Collaborator - University of Oxford
Tim Holt - Collaborator - University of Oxford
Jan Roast - Collaborator - Oxfordshire Family Support Network
Margaret Smith - Collaborator - University of Oxford
HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation;CPRD Aurum Ethnicity Record;CPRD Aurum Pregnancy Register