Blood glycated hemoglobin level is not associated with disease progression in amyotrophic lateral sclerosis.

A high glycemic index and high glycemic load diet has been associated with slower progression of amyotrophic lateral sclerosis (ALS), suggesting a benefit from high blood glucose levels. We examined the association between average blood glucose level and ALS progression in two independent cohorts. Sporadic ALS patients enrolled in the ALS Multicenter Cohort Study of Oxidative Stress (ALS COSMOS) who completed a 3-month follow-up visit and had available blood samples were included. Hemoglobin A1c (HbA1c) was measured from whole blood collected at the 3-month follow-up. From the Pooled Resource Open-Access ALS Clinical Trials (PRO-ACT) database, we included ALS patients with one or more HbA1c measurements at enrollment and available death information. Associations between HbA1c with revised ALS functional rating scale (ALSFRS-R)/ALSFRS total score change, and tracheostomy-free survival/survival were examined in these cohorts using linear regression, linear mixed-effects models, and Cox proportional hazard models, adjusted for covariates. In the ALS COSMOS cohort (n = 193), HbA1c level was not significantly associated with the change in the ALSFRS-R total score from baseline to the 3-month follow-up (p = 0.8) nor baseline to the 6-month follow-up (p = 0.4). No significant association was found between HbA1c level and tracheostomy-free survival (p = 0.8). In the PRO-ACT cohort (n = 928), no significant association was found between HbA1c level and the rate of ALSFRS decline in the first 200 days (p = 0.81 for interaction) nor between HbA1c level and survival (p = 0.45). We did not find convincing evidence that mean blood glucose level is associated with disease progression among ALS patients.