Background: Adolescent idiopathic scoliosis (AIS) is common deformity with unknown cause. Previous studies have suggested the abnormal serum leptin and ghrelin level in AIS girls. The aim of present study was to evaluate whether the serum leptin and ghrelin level could serve as risk factor in predicting the curve progression in AIS girls. The associations between them and the physical characteristics were also investigated.
Materials and methods: Circulating leptin and ghrelin levels from 105 AIS girls and 40 age-matched non-AIS girls were examined by enzyme-linked immunosorbent assay. The correlations between ghrelin and leptin levels and growth-related parameters (age, weight, corrected height, corrected BMI, main Cobb angle, and Risser sign) were analyzed in AIS group. Multivariate logistic regression was used to investigate factors predicting curve progression in AIS girls.
Results: A significantly lower leptin level (6.55 ± 2.88 vs. 8.01 ± 3.12 ng/ml, p < 0.05) and a higher ghrelin level (6.33 ± 2.46 vs. 4.46 ± 2.02 ng/ml, p < 0.05) were found in all AIS patients, as compared with normal controls. Curve progression patients had a higher ghrelin level than stable curve patients (7.61 ± 2.48 vs. 5.54 ± 2.11 ng/ml, p < 0.01); for leptin level, there was no significant difference between progression and stable group. The results of multivariate logistic stepwise regression showed that premenarche status, initial main Cobb magnitude that was more than or equal to 23°, high ghrelin level (≥7.30 ng/ml), and lower Risser grade (grades 0 to 2) were identified as risk factors in predicting curve progression. Ghrelin levels of >6.48 ng/ml were predictive for curve progression with 70.00 % sensitivity and 72.31 % specificity, and the area under the curve (AUC) was 0.741 (95 % confidence interval 0.646-0.821).
Conclusions: High ghrelin level may serve as a new quantitative indicator for predicting curve progression in AIS girls.