Distribution of BMIs across our FA cohort and correlation with serum serotonin. (A) Plot showing the range of BMI centiles represented within our cohort of patients with FA. Nearly two-thirds of patients fall at the extremes, with BMI underweight or overweight. (B) Note the logarithmic scale. Significant inverse correlation between serum serotonin values and BMI centile within our FA cohort. Higher elevations in serotonin are associated with lower BMI; Spearman’s correlation coefficient, −0.51; P = .013.