Fibromyalgia syndrome in children--an outcome study

To assess the outcome of fibromyalgia syndrome (FM) in a 30-month followup study of children with FM.

In the original study to assess the prevalence of FM in healthy schoolchildren, we found 21 children with FM and an additional 7 fulfilling the point count criterion only (11 of 18). Fifteen of the 21 and all 7 were recruited for a 2nd assessment in our present study. In all children, a count of 18 tender points (TP) was conducted by thumb palpation. Tenderness of 9 of the TP sites as well as 4 control point sites was further assessed using a Chatillon dolorimeter. All children were questioned concerning the presence of widespread pain or aching. Children were considered to have FM if they met the American College of Rheumatology criteria for diagnosis.

After 30 months, 11 of the 15 children with FM (73%) were no longer fibromyalgic. The mean point count of the 15 children significantly decreased from 12.5 to 4.6 (p < 0.001). The mean tenderness threshold of the 9 tender sites increased from 2.4 to 3.4 kg (p < 0.01), and the mean tenderness threshold of the 4 control sites increased from 4.1 to 5.6 kg (p < 0.05). Of the 7 children initially fulfilling the point count criterion only, none had developed FM. Their mean point count decreased from 11.4 to 3.4 (p = 0.001), and their mean tenderness thresholds increased from 2.7 kg to 3.9 kg (p = 0.001) at tender sites and from 4.3 kg to 6.8 kg (p < 0.001) at control sites.

We suggest that the outcome of FM in children is more favorable than in adults. More followup studies are needed to clarify the longterm outcomes of FM in children and adults.