The genetic contribution to severe post-traumatic osteoarthritis.
OBJECTIVE
to compare the combined role of genetic variants loci associated with risk of knee or hip osteoarthritis (OA) in post-traumatic (PT) and non-traumatic (NT) cases of clinically severe OA leading to total joint replacement.


METHODS
A total of 1590 controls, 2168 total knee replacement (TKR) cases (33.2% PT) and 1567 total hip replacement (THR) cases (8.7% PT) from 2 UK cohorts were genotyped for 12 variants previously reported to be reproducibly associated with risk of knee or hip OA. A genetic risk score was generated and the association with PT and NT TKR and THR was assessed adjusting for covariates.


RESULTS
For THR, each additional genetic risk variant conferred lower risk among PT cases (OR=1.07, 95% CI 0.96 to 1.19; p=0.24) than NT cases (OR 1.11, 95% CI 1.06 to 1.17; p=1.55×10⁻⁵). In contrast, for TKR, each risk variant conferred slightly higher risk among PT cases (OR 1.12, 95% CI 1.07 to 1.19; p=1.82×10⁻⁵) than among NT cases (OR 1.08, 95% CI 1.03 to 1.1; p=0.00063).


CONCLUSIONS
Based on the variants reported to date PT TKR cases have at least as high a genetic contribution as NT cases.
Academic Rheumatology, Nottingham City Hospital, Nottingham, UK. ana.valdes@kcl.ac.uk
Ana M
AM
Valdes
Sally A
SA
Doherty
Kenneth R
KR
Muir
Margaret
M
Wheeler
Rose A
RA
Maciewicz
Weiya
W
Zhang
Michael
M
Doherty
D000368:Aged; D019644:Arthroplasty, Replacement, Hip; D019645:Arthroplasty, Replacement, Knee; D015992:Body Mass Index; D016022:Case-Control Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D025981:Hip Injuries / Q000150:complications*; D006801:Humans; D007718:Knee Injuries / Q000150:complications*; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000209:etiology / Q000235:genetics* / Q000601:surgery; D020370:Osteoarthritis, Knee / Q000209:etiology / Q000235:genetics* / Q000601:surgery; D012307:Risk Factors
Epidemiology; Gene Polymorphism; Osteoarthritis