Association Between the Ratio of Omega-6/Omega-3 Fatty Acids Intake to Plasma Malondialdehyde Level in Patients with Knee Osteoarthritis

One of several factors in the pathogenesis of osteoarthritis (OA) is the generation of oxidative stress, inducing lipid peroxidation, and producing malondialdehyde (MDA). Omega-3 fatty acids have role in inhibiting the oxidative stress, but their levels are determined by the omega-6/omega-3 ratio. This study aims to investigate the association between the ratio of omega-6/omega-3 intake and plasma MDA level in knee OA patients. This study was conducted at orthopedic clinic at Bhayangkara Hospital and Cipto Mangunkusumo Hospital, in grade 2-4 of knee OA patients, aged between 40-60 years (n=57). The 1-month-history of omega-3 and omega-6 intake was obtained by using semi-quantitative food frequency questionnaire. The omega-6/omega-3 ratio was calculated by dividing the average daily intake of total omega-6 by the average daily intake of total omega-3. The plasma MDA level was measured by Wills spectrophotometry. The median for omega-3 and omega-6 intake were 0,864 and 6,830 g/day. Thus the ratio of omega-6/omega-3 intake was 8,8:1, and the mean plasma MDA level was 0,773 nmol/mL. Through multiple linear regression test, the results found were the increase of 1 unit of omega-6/omega-3 intake ratio would increase MDA level of 0,023 nmol/mL (β = 0,023, 95% CI = 0,004 − 0,042, p = 0,017).