Their numbers might be small but Australian residents with sickle cell disease (SCD) have high levels of healthcare usage including ED presentations, hospital admissions and outpatient blood transfusions.

The burden of chronic complications accumulating in the adult SCD population has implications for the planning and delivery of health services, researchers say.

The first national overview of SCD patients in Australia describes 359 participants with a sickling disorder in the Australian Haemoglobinopathy Registry (HbR).

Patients had a median age of 17.9 years, were 51% male, and were diagnosed at a young age – at about 0.7 years for the paediatric population and 2.6 years for the adult population. Most of the children were born in Australia while about 45% of the adults were born in Australia.

The majority of patients, particularly within the paediatric population, are of sub-Saharan African origin.

Reflecting the predominant ethnicity, the majority of patients had a diagnosis of SCD with a phenotype of HbSS, followed by HbSC and HbS/beta thalassaemia.

The study, published in the Internal Medicine Journal [link here], said acute complications were reported in 83.5% of patients.

The most frequent were painful vasoocclusive crises (VOC), infection requiring hospitalisation and acute chest syndrome.

Chronic complications such as chronic pain, avascular necrosis and neurocognitive impairment were reported in 34.4% of patients overall, and more commonly in adults (59.4%) than children (14.8%).

Management

The study found just over half the patients were receiving hydroxyurea (54%), prophylactic antibiotics (53.3%), vitamin D (58.8%) and folic acid supplementation (68.5%).

“A minority (13.7%) were reported to be receiving iron chelation, with the proportion increasing from 5.6% in children to 23.3% in adults (P < 0.001),” it said.

Overall, one third of patients (34.4%) received regular red blood cell transfusions – with higher rates of useage in adults (56.9%) compared to children (15.2%).

Of these patients, 43.7% received between 31 and 80 units over the preceding 12 months and 10.3% received >80 units.

“Greater transfusion requirements are associated with an increased risk of associated complications, including the potential to develop RBC alloantibodies, reported in 14% of adults in the HbR,” it said.

The study found 38% of people with SCD presented to an ED in the preceding 12 months and of those, almost all required a hospital admission typically for VOC or infections.

The authors, led by senior investigators Professor Joy Ho (Royal Prince Alfred Hospital) and Professor Erica Wood (Monash University), called for expansion of health resources to address the transition for adolescents to adult care and the cumulative burden of care as the SCD population ages.

“With increasing survival, chronic complications of SCD accumulate and are compounded by non-SCD-related conditions,” they said.

“These new data from the Australian HbR provide a greater understanding of the natural history of SCD and outcomes in our population, highlighting the need for adequate resourcing and further therapies to address high rates of acute and chronic complications.”