Progression of haemophilic arthropathy in children: a Lithuanian--Danish comparative study.

Recurrent bleeding into joints initiates a sequence of events leading to a progressive joint damage in people with severe haemophilia. This is a continuous process during childhood and adolescence, therefore joint abnormalities may be minimal on physical examination in very young children - even those receiving on-demand treatment. The aim of our study was to quantify the burden of arthropathy in Lithuanian patients who had been treated exclusively by on-demand substitution and compare their physical joint health with age-matched Danish patients who received prophylaxis from an early age. Boys, aged 4-17 years, with severe haemophilia and no signs of inhibitors were included in the study. Joint outcome based on the Haemophilia Joint Health Score (HJHS) was analysed in two different treatment groups and compared within the matched pairs. In total, 32 (16 in each treatment group) patients were enroled. A total of 192 joints were evaluated. Joint status according to treatment strategy was strikingly different: 27.4 for on-demand vs. 3.3 for prophylaxis (<0.001) group. Significance of the difference in joint status comparing different treatment strategies was equally strong both in younger (4-9 years) and older (10-17 years) patient groups: 2.2 vs. 12.5 (P = 0.0002) and 3.9 vs. 36.3 (P < 0.0001) respectively. The results further demonstrate the unequivocal effect of prophylaxis on joint status and give an insight into early and late manifestations of joint impairment based on the HJHS in haemophilia patients with treatment on-demand compared with joint changes that may develop over the time with the preventative treatment.