Family history and its association to curve size and treatment in 1,463 patients with idiopathic scoliosis.

PURPOSE: To study family history in relation to curve severity, gender, age at diagnosis and treatment in idiopathic scoliosis. METHODS: A self-assessment questionnaire on family history of scoliosis was administered to 1,463 untreated, brace or surgically treated idiopathic scoliosis patients. RESULTS: Out of the 1,463 patients, 51 % had one or more relatives with scoliosis. There was no significant difference between females and males, nor between juvenile and adolescent study participants in this respect (p = 0.939 and 0.110, respectively). There was a significant difference in maximum curve size between patients with one or more relatives with scoliosis (median 35°, interquartile range 25) and patients without any relative with scoliosis (median 32°, interquartile range 23) (p = 0.022). When stratifying patients according to treatment (observation, brace treatment or surgery), we found that it was more common to have a relative with scoliosis among the treated patients (p = 0.011). The OR for being treated was 1.32 (95% CI 1.06-1.64) when the patient had a relative with scoliosis, compared to not having. CONCLUSIONS: Larger curve sizes were found in patients with a family history of scoliosis than in the ones without. No relation between family history and gender or between family history and age at onset of idiopathic scoliosis was found. Although the presence of a family history of scoliosis may not be a strong prognostic risk factor, it indicates that these patients are at higher risk of developing a more severe curve.