Physical Rehabilitation in Adults With Sickle Cell Anemia: Effects on Muscle Function, Functional Capacity and Quality of Life

Over the past 40 years, Public Health measures have led to an impressive decline in infant mortality related to sickle cell disease (SCA) and, thus, modified its evolution. Sickle cell disease went from a life-threatening disease in childhood in the 1970s to a chronic disease of adults today. In Brazil, the median age of cases that evolved to death was 26.5 years in Bahia, 31.5 years in Rio de Janeiro and 30 years in São Paulo. In a study carried out in Minas Gerais, the average age at the time of death was 33.5 years considering only adults; this was higher in the female gender (46.5 years) and the majority occurred as a result of acute events.

Osteoarticular and muscle involvement is common in adults with sickle cell disease and has high morbidity. Since bone microcirculation is a place where sickling of red blood cells is common, there is a tendency for thrombosis, infarction and necrosis. The osteoarticular lesion is characterized mainly by osteonecrosis, osteomyelitis and arthritis, with frequent involvement of the hip and shoulder bones and the vertebral bodies.

Bone changes in SCA can be grouped into two main forms: those associated with ischemic events and those associated with bone marrow hyperplasia due to chronic anemia. The pathogenesis of microvascular occlusion, the key event of vaso-occlusive crises, is complex and involves the activation of leukocytes, platelets and endothelial cells, in addition to hemoglobin S containing red blood cells. These events can occur in almost any organ, but are particularly common in the bone marrow, possibly because of its hypercellularity, leading to a decrease in blood flow and regional hypoxia. There is also evidence of a possible association between changes in calcium metabolism and the occurrence of osteoporosis in people with sickle cell disease.

Regarding muscle disease, some studies have shown a decrease in both muscle strength and endurance in individuals with sickle cell disease. General amyotrophy results from repeated episodes of vasoocclusion and ischemia of the muscles, sometimes silent or subclinical, which occur in sickle cell anemia and are known to induce dysfunction and, eventually, skeletal muscle necrosis. Sickle cells and oxidative stress can cause microvascular obstruction and damage peripheral muscles in patients with SCA. Consequently, there are marked changes in skeletal muscle structure, with rarefaction of microvessels and decreased capillary tortuosity.

The main cause of emergency care for people with SCA is painful osteoarticular crises, which are observed in about 70% of cases, while the most frequent complications that require hospitalization in these individuals are the vaso-occlusive crisis and osteomyelitis. Other bone complications in acute SCA are stress fractures, orbital compression, vertebral collapse and spinal necrosis.