Association of dietary inflammatory index with body composition and disease progression in adults with amyotrophic lateral sclerosis: evidence from a cross-sectional study.

BACKGROUND

For decades, diet's pro-inflammatory properties have been considered a potential risk factor in the onset of amyotrophic lateral sclerosis (ALS). This study aimed to explore the association of dietary inflammatory index (DII) with body composition and disease progression in adult individuals with ALS.

METHODS

Clinically stable adults aged 18 years and older were enrolled for this study from the neuromuscular disorders clinic at Imam Khomeini Hospital. All participants met the EI Escorial criteria for ALS. Participants completed a 153-item dish-based semi-quantitative food frequency questionnaire (FFQ), which was developed and validated for Iranian adults. Multiple linear regression analyses were performed to examine the association between DII and the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R), Medical Research Council (MRC) score, disease progression rate (DPR), and body composition among adult participants with ALS.

RESULTS

This cross-sectional study involved 93 adult participants with ALS, comprising 29 women and 64 men (aged 56.95 ± 12.05 years). Participants in the third DII tertile had significantly reduced consumption of several nutrients, comprising vitamin E (P < 0.001), vitamin A (P < 0.001), vitamin B6 (P < 0.001), folic acid (P = 0.006), vitamin K (P < 0.001), fluoride (P = 0.009), potassium (P < 0.05), and selenium (P = 0.003). DPR displayed a significant negative association with the third tertile of DII (β T3 vs. T1= -1.1, 95CI%:-2.2, -0.04; Ptrend= 0.04), signifying a significant relationship after accounting for confounders, including age, gender, BMI, physical activity, and history of ALS.

CONCLUSION

Our findings suggest that higher inflammatory dietary patterns might be associated with a slower rate of disease progression in adults suffering from ALS. To elucidate these findings, randomized controlled trials are warranted.