Earlier Steroid Treatment In Pediatric Lupus Patients Is Related to Higher Risk of Bone Disease
- Age at time of corticosteroid administration is a risk factor for osteonecrosis in pediatric patients with systemic lupus erythematosus.
Authors: Nakamura J, Saisu T, Yamashita K, Suzuki C, Kamegaya M, and Takahashi K. (2010).
Arthritis & Rheumatism, 62: 609-615.
What is the topic?
Steroids are frequently used to treat moderate-to-severe lupus flares because they are highly effective and work quickly. However, steroids have many serious side effects, including potentially severe damage to joints or "osteonecrosis," which is an interruption of the blood supply to the bone. How much of a risk this may pose for children with lupus or younger adults with lupus has not been well-studied.
What did the researchers hope to learn?
The researchers hoped to learn whether starting steroids at a younger age is a risk factor for osteonecrosis.
Who was studied?
169 lupus patients were studied, including: children (less than 15 years old), adolescents (15-20 years old), and adults (20 years or older). Most of the patients were adults, 10% were children, and 15% were adolescents.
How was the study conducted?
Magnetic resonance imaging (MRI) was used to look at hip and knee joints in the people being studied. Based on the MRI results, the presence or absence of osteonecrosis was determined for each person.
What did the researchers find?
Osteonecrosis was not found in any patient younger than 14 years of age and was generally less common in children than in adolescents and adults.
When the researchers examined the steroid doses being taken by all of the people in the study, they found that the pediatric patients were taking the least and that the adolescents and adults were taking about the same amount. But, steroids work according to the weight of the patient, and are supposed to be given in amounts based on weight. This means that a child or a small person gets the same effects from lower doses when compared to bigger people. When the researchers looked at the doses and factored in the weights of the patients, they found that the children were actually taking the highest doses, while the adolescents and adults were taking about the same amount. In the children, those with osteonecrosis had started steroids at a younger age than those who did not develop this complication.
What were the limitations of the study?
This study was too small and the numbers of younger patients even smaller to be able to know the real risks of osteonecrosis in children with lupus. It is also not totally certain that it was the steroids that were responsible for the osteonecrosis. Taking steroids at a younger age may also reflect a more ill subgroup of patients and there may be other factors involved in the bone complications. Age may not be the real factor, either. If ostenecrosis is an increased risk in children, the younger age of starting treatments might just reflect a longer duration of lupus and, therefore, a longer duration of other risk factors.
What do the results mean for you?
The results of this study suggest the possibility that steroids might contribute to a serious bone complication in some children with lupus. It is very important that new biologic treatments for lupus, which are now being widely tested for adults with lupus, also be tested for children with lupus. Because children are such a vulnerable population, treatments for them often lag behind the new treatments for adults. However, this backfires on children who have illnesses for which current treatments are not optimal.