Dietary omega polyunsaturated fatty acid intake and patient-reported outcomes in systemic lupus erythematosus: The Michigan Lupus Epidemiology & Surveillance (MILES) Program

OBJECTIVE To examine associations between dietary intake of omega-3 (n-3; generally anti-inflammatory) and omega-6 (n-6; generally pro-inflammatory) fatty acids and patient reported outcomes in systemic lupus erythematosus (SLE).METHODS This study was based on the population-based Michigan Lupus Epidemiology & Surveillance (MILES) Cohort. Estimates of n-3 and n-6 intake were derived from Diet History Questionnaire II items (DHQ II; past year with portion size version). Patient-reported outcomes included self-reported lupus activity (Systemic Lupus Activity Questionnaire/SLAQ). Multivariable regression, adjusted for age, sex, race, and body mass index, was used to assess associations between absolute intake of n-3 and n-6, as well as the n-6:n-3 ratio, and patient-reported outcomes.RESULTSAmong 456 SLE cases, 425 (93.2%) were female, 207 (45.4%) were black, and mean age was 52.9+12.3 years. Controlling for potential confounders, the average SLAQ score was significantly higher by 0.3 points [(95% CI 0.1, 0.6); p=0.013] with each unit increase of the n-6:n-3 ratio. Both lupus activity and PROMIS-Sleep Disturbance scores were lower with each 1g/1000 Kcal increase of n-3 fatty acids [SLAQ regression coefficient β=-0.8 (95% CI -1.6, 0.0), p=0.055; PROMIS-Sleep β=-1.1 (95% CI -2.0, -0.2), p=0.017]. Higher n-3 intakes were non-significantly associated with lower levels of depressive symptoms and comorbid fibromyalgia, and higher quality of life, whereas results for the n6:n3 ratio trended in the opposite direction.CONCLUSIONThis population-based study suggests that higher dietary intake of n-3 fatty acids, and lower n-6:n-3 ratios, are favorably associated with patient-reported outcomes in SLE, particularly self-reported lupus activity and sleep quality.