Baseline Oxidative Stress Is Associated with Memory Changes in Omega-3 Fatty Acid Treated Coronary Artery Disease Patients

OBJECTIVE: This study investigated whether pretreatment oxidative stress, measured by lipid hydroperoxides (LPH), 4-hydroxy-2-nonenal (4-HNE), 8-isoprostane (8-ISO), and malondialdehyde (MDA), was associated with improvement in immediate recall among n-3 PUFA-treated coronary artery disease patients. METHODS: This was a secondary analysis of the CAROTID trial (NCT00981383). Composite immediate recall, measured using the California Verbal Learning Test, Second Edition, and the Brief Visuospatial Memory Test-Revised, was assessed. LPH, 4-HNE, 8-ISO, MDA, and n-3 PUFA concentrations were analysed from fasting blood. Patients then received either n-3 PUFA treatment or placebo for 12 weeks, after which composite immediate recall was reassessed. Linear regression was used to investigate relationships between lipid peroxidation markers and changes in composite immediate recall in each treatment group. RESULTS: Eighty-five patients (age = 61.1 ± 8.5, 77% male, mean years of education = 15.3 ± 3.4) were included (n = 46 placebo, n = 39 n-3 PUFA). After adjusting for multiple comparisons and potential confounders, greater baseline concentrations of LPH (β = 0.45, p = .002) and 4-HNE (β = 0.38, p = .005) were associated with greater improvement in composite immediate recall among n-3 PUFA-treated patients. No other associations were observed. CONCLUSIONS: N-3 PUFA treatment may be more likely to improve immediate recall in patients with greater oxidative stress.