Weight maintenance following enteral nutrition is associated with prolonged survival in amyotrophic lateral sclerosis.

OBJECTIVE

To investigate the association between energy intake at the initiation of enteral nutrition (EN), subsequent changes in body mass index (BMI), and survival in patients with amyotrophic lateral sclerosis (ALS).

METHODS

This retrospective study included 121 patients with ALS who received EN. Annual BMI decline rates (∆BMI, kg/m2/year) were calculated for three periods: from symptom onset to diagnosis (T1-T2), from diagnosis to EN initiation (T2-T3), and from EN initiation to post-EN assessment (T3-T4). Energy intake per weight (E/W, kcal/kg/day) at EN initiation was also assessed. Survival after EN initiation was analyzed using Kaplan-Meier methods and Cox proportional hazards models.

RESULTS

Post-EN BMI decline (∆BMIT3-T4) showed a significant negative correlation with E/W at T3 (p < 0.001). Patients with lower post-EN BMI decline (∆BMI < 0.8 kg/m2/year) had significantly longer survival after EN initiation than those with greater BMI decline (p < 0.001). Multivariate Cox analysis identified ∆BMIT3-T4 and pre-EN respiratory decline as independent predictors of post-EN survival. Subgroup analyses demonstrated that patients who maintained body weight after EN had better survival irrespective of energy intake at EN initiation.

CONCLUSION

Weight maintenance following EN was associated with prolonged survival in ALS, whereas energy intake at EN initiation alone was not. These findings suggest that the survival benefit of nutritional intervention may be mediated through stabilization of body weight rather than caloric intake per se.