Diet quality is associated with pain intensity and quality of life in asample of patients with knee osteoarthritis: a cross-sectional study

Introduction: Knee osteoarthritis (KOA) is the most common degenerative joint disease resultingin bone pain and disability. The aim of current study is to determine diet quality by healthy eatingindex (HEI)-2015 in association with pain and functional status among a sample of participantswith primary knee OA.Methods: In this cross-sectional study, 220 patients with knee OA were recruited via conveniencesampling in the outpatient clinics of Tabriz University of Medical Sciences between April andSeptember 2018. The HEI-2015 score was calculated from dietary data collected using aFood Frequency Questionnaire (FFQ). Visual analogue scale, Western Ontario and McMasterUniversities Osteoarthritis Index and the SF36 quality of life (QoL) questionnaire were appliedto measure the pain intensity, functional status and QoL in the participants, respectively.Participants were categorized based on the quintile cutoff points of HEI score including 42-62,63-69, 70-75, 76-78 and 79-100.Results: The mean score of HEI was 70.62 ± 10.18 (range: 42–89). Participants with greater HEI-2015 scores had higher total energy intake (P = 0.008) and greater dietary intake of carbohydrates(P = 0.01), protein (P = 0.009), monounsaturated fatty acids (P = 0.01), polyunsaturated fatty acids(P = 0.007) and fiber (P = 0.009) and lower intake of saturated fatty acids (P = 0.005). Participantsin higher quintiles of HEI had significantly lower pain intensity (P = 0.001) and higher scoresof physical function (P = 0.001), pain (P = 0.001) and role limitation due to physical problems(P = 0.005) subscales of SF-36 QoL questionnaire in comparison with participants in lowerquintiles of HEI-2015.Conclusion: The HEI-2015 score is associated with pain intensity and two domain of QoL inpatients with knee OA.