The association between dietary sugar intake and neuromyelitis optica spectrum disorder: A case-control study

Neuromyelitis optica spectrum disorder (NMOSD) is an uncommon autoimmune disease of the central nerves system (CNS) by inflammatory nature. The effects of high dietary sugar intake on inflammation and dysbiosis have been received more attention in recent years. The aim of the present study was to investigate the association between various types of dietary sugar intake and NMOSD odds and clinical features.

The current case-control study was conducted among 70 patients with definite NMOSD diagnosis based on 2015 international consensus criteria and 164 hospital-based controls. Demographic and anthropometric information in all participants and disease characteristics just in case group were obtained. Dietary data during the past year of study attendance was collected by a validated 168-item food frequency questionnaire. Participants were stratified into 3 tertiles according to each type of sugar intake and the third tertile considered as reference in multivariate regression models. The correlation between dietary sugar and disease features were analyzed using Pearson correlation test.

The mean ± SD of total sugar intake increased from 80.73 ± 17.71 to 208.71 ± 57.93 g/day across tertiles of total sugar intake. In fully adjusted model, lower intake of sugar was associates with decreased odds of NMOSD in the first tertile vs third tertile by ORs of: 0.02(CI:0.00-0.08; p-for-trend:0.00), 0.02(CI:0.00-0.10; p-for-trend:0.00), 0.23(CI:0.08-0.61; p-for-trend:0.00), 0.19(CI:0.06-0.58; p-for-trend:0.00) and 0.16(CI:0.05-0.51; p-for-trend:0.00) for glucose, fructose, galactose, lactose and sucrose, respectively. The odds of NMOSD had a 1.72-fold (CI: 1.43-2.03; p-for-trend:0.00) significant raise per every 10 g increase for total sugar intake. There was no significant correlation between various types of dietary sugar intakes and relapse rate or patients' disability.

The present study proposes a possible direct association between high intake of various sugar types and odds of suffering from NMOSD. More investigations are needed to prove this results.