In May researchers in Sweden published the results of a study analyzing whether physical activity, accompanied by a long-term prophylactic (preventive) treatment regimen, is a significant determining factor in the prevention of osteoporosis in patients with severe hemophilia. The lead investigator of the study was Mohamed Mansour Khawaji, Malmö University Hospital, Lund University.

Osteoporosis is a degenerative condition characterized by loss of bone mass and degeneration of bone tissue. Left untreated, bones become fragile and are prone to fractures, especially in the hip, spine, neck and wrist. A bone mineral density (BMD) test helps determine whether a patient has osteoporosis. Physical activity, particularly weight-bearing exercise, is one of the key contributors to maintaining and enhancing bone strength.

Prior reports have shown that hemophilia patients often have reduced bone density. In addition, severe hemophilia patients not receiving prophylaxis are more likely to engage in less physical activity due to chronic joint bleeds that cause damage to joints (arthropathy), pain and limitations in range of motion.   

Of the 30 patients (28 with hemophilia A, 2 with hemophilia B), all received regular long-term prophylaxis (2-3 factor infusions per week) for an average of 29.5 years. The majority (25) started the regimen in early childhood (average age was 2 years), five began prophylaxis in late childhood and adolescence (ranging from 7-15 years old). An enhanced BMD test was conducted in each patient.

Physical activity was assessed through a “Modifiable Activity Questionnaire,” a self-reporting tool used on leisure and occupational activities for the previous 12 months. Nearly all participants reported engaging in weight-bearing activities (96.6%). Seventeen (56.6%) participated in “vigorous activities” such as wood chopping and jogging, while 18 (60%) engaged in nonweight-bearing activities, including cycling and swimming. Walking was also a commonly cited activity (63.3%).    

Investigators only reported a statistically significant correlation between bone density in the lumbar area of the spine and the duration/intensity of vigorous physical activity. They also reported no significant correlation between vigorous physical activity and bone density at the hip, neck and trochanter (bony prominences near end of the thigh bone).

“In conclusion, with adequate long-term prophylaxis, patients with haemophilia are maintaining bone mass, whereas the level of physical activity in terms of intensity and duration play a minor role. In addition, these results may support the proposition that the responsiveness to either an increase or a decrease in mechanical strain is probably more important for bone mass in children and adolescents rather than in adults and also supports the importance of starting prophylaxis early in life so that the children can lead active life and normal bone density when they grow up,” reported the authors.

The study, “Physical Activity for Prevention of Osteoporosis in Patients with Severe haemophilia on Long-term Prophylaxis,” was published in the May 2010 issue of Haemophilia.