Bone health assessment in haemophilic arthropathy: A single centre study from Kolkata, West Bengal, India

Abstract Background Haemophilia has been associated with increased prevalence of low bone mineral density (BMD) which in turn may aggravate haemophilic arthropathy. Dual-energy X-ray absorptiometry (DEXA) is the gold standard for assessing BMD but is not widely available across India. Markers of bone turnover like bone-specific alkaline phosphatase (b-ALP) reflect osteoblastic turnover and may be surrogate to low BMD. Aim To evaluate how bone health in people with haemophilia (PWH) can be assessed by serum vitamin D3 and b-ALP level, correlated with the degree of arthropathy. Methods In this cross-sectional study, people with haemophilia A and B of all severities with arthropathy involving ≥3 joints were included. The number of joints affected by haemophilic arthropathy was recorded. Hemophilia Joint Health Score (HJHS) and Pettersson score were calculated for each patient. Levels of serum calcium, phosphorus, vitamin D3 and b-ALP were assayed in all cases. Results A total of 320 PWH were included; the majority (85%; 272/320) had severe haemophilia, 13.44% (43/320) moderate haemophilia and 1.56% (5/320) mild haemophilia. With increasing age, the number of joints involved increased significantly (r=0.2250, p<0.05). When adjusted for age, b-ALP was higher than normal for the majority of PWH (88.75%). Increased number of joints involved and severity of disease had a positive correlation with higher-than-normal b-ALP (adjusted for age) (r=0.2112, p=0.0001). A significant positive correlation was seen between Pettersson score and HJHS score (r=0.1126, p=0.04). There was no significant correlation between number of joints involved and serum vitamin D3 level across the whole cohort. (p<0.05). Conclusion PWH with severe disease and haemophilic arthropathy have higher than normal b-ALP, which in turn reflects increased bone turn over and low BMD. Hence, b-ALP may be a useful marker to help assess bone health in PWH, particularly in settings where access to DEXA scans is constrained.