Table 5.

Stratified analysis according to arthropathy status at initiation of regular prophylaxis

Arnold–Hilgartner stage at initiation of regular prophylaxis		Stage 0				Stage ≥ I
		HR	95% CI		p	HR	95% CI		p
Regular prophylaxis at first visit to our institute	No	Reference				Reference
	Yes	0.21	0.08–0.53		0.001	0.95	0.56–1.62		0.843

Analysis of the association between prophylaxis status at the first visit to our institute and subsequent progression to hemophilic arthropathy, stratified by Arnold–Hilgartner stage at initiation of regular prophylaxis (stage 0 vs stage ≥ I)

Among joints classified as stage 0 at prophylaxis initiation, regular prophylaxis at the first visit to our institute was associated with a lower risk of progression to hemophilic arthropathy (HR 0.21, 95% CI 0.08–0.53; p = 0.001). In contrast, among joints classified as stage ≥ I at prophylaxis initiation, prophylaxis status at the first visit to our institute was not clearly associated with subsequent progression (HR 0.95, 95% CI 0.56–1.62; p = 0.843)

CI confidence interval, HA hemophilic arthropathy, HR hazard ratio