BOF 137
Epidemiology of Psoriatic arthropathy, all are true,
except:
1-in 20% it precedes the onset of the skin disease
2-simultaneous occurrence of the skin plaques and
joint involvement is very common
3-approximately up to 20% of cases seronegative
spondyloarthritis is due to psoriatic arthropathy
4-psoriatic arthropathy occurs in 1in 1000 of the
general population
5-the usually age of onset is between 25 and 40 years