The medical food Souvenaid affects brain phospholipid metabolism in mild Alzheimer's disease: results from a randomized controlled trial

Background: Synaptic dysfunction contributes to cognitive impairment in Alzheimer's disease and may be countered by increased intake of nutrients that target brain phospholipid metabolism. In this study, we explored whether the medical food Souvenaid affects brain phospholipid metabolism in patients with Alzheimer's disease. Methods: Thirty-four drug-naive patients with mild Alzheimer's disease (Mini Mental State Examination score >= 20) were enrolled in this exploratory, double-blind, randomized controlled study. Before and after 4-week intervention with Souvenaid or an isocaloric control product, phosphorus and proton magnetic resonance spectroscopy (MRS) was performed to assess surrogate measures of phospholipid synthesis and breakdown (phosphomonoesters [PME] and phosphodiesters [PDEs]), neural integrity (N-acetyl aspartate), gliosis (myo-inositol), and choline metabolism (choline-containing compounds [tCho]). The main outcome parameters were PME and PDE signal intensities and the PME/ PDE ratio. Results: MRS data from 33 patients (60-86 years old; 42% males; Souvenaid arm n = 16; control arm n = 17) were analyzed. PME/ PDE and tCho were higher after 4 weeks of Souvenaid compared with control (PME/ PDE least squares [LS] mean difference [95% CI] 0.18 [0.06-0.30], p = 0.005; tCho LS mean difference [95% CI] 0.01 [0.00-0.02], p = 0.019). No significant differences were observed in the other MRS outcome parameters. Conclusions: MRS reveals that Souvenaid affects brain phospholipid metabolism in mild Alzheimer's disease, in line with findings in preclinical studies.