POS1095 FOOD SOURCES OF DIETARY FIBRE AND RISK OF TOTAL KNEE REPLACEMENT RELATED TO SEVERE OSTEOARTHRITIS, THE SINGAPORE CHINESE HEALTH STUDY
Authors: Y. Y. Leung, A. Jin, K. Tan, L. W. Ang, J. M. Yuan, W. P. Koh
Journal: Annals of the Rheumatic Diseases (2021)

Background: Although fibre intake was inversely associated with the risk of symptomatic knee osteoarthritis (KOA) in a US study, this association was partially confounded by lower body mass index (BMI) in those with higher fibre intake. Objectives: We evaluated the association between fibre intake and its food sources, and the risk of total knee replacement (TKR) due to severe KOA. Methods: We used data from the Singapore Chinese Health Study, a prospective cohort study that recruited 63,257 participants aged 45-74 years from 1993 to 1998. At baseline, we assessed diet using a validated 165-item semi-quantitative food frequency questionnaire, together with BMI and lifestyle factors. Incident TKR cases were identified via record linkage with nationwide hospital discharge database through 2017. We used multivariable Cox regression models to compute hazard ratio (HR) and the corresponding 95% confidence interval (CI) for risk of TKR. Results: There were 2,816 cases of incident TKR due to severe KOA. Total fibre intake at baseline was not associated with risk of TKR after adjustment for confounders. Among the food sources of fibre, higher intake of legumes was associated with lower risk of TKR in dose-dependent manner; compared with those having the lowest quartile intake, HR (95% CI) was 0.86 (0.76, 0.96) for the highest quartile ( p for trend = 0.004). This association was consistent after including BMI in the model, and homogenous across BMI categories. The consumption of other fibre sources, namely grain products, nuts and seeds, soy food, fruits and vegetables, was not associated with risk of TKR. Conclusion: Intake of legumes, but not total fibre, was associated with a reduced risk of TKR. Further research is needed to replicate our findings, and to evaluate possible biological mechanisms that could explain the effect of dietary legumes in pathogenesis or progression of KOA. Table 1. Hazard ratios (95% confidence intervals) for risk of total knee replacement according to intake of fibre (only shown total fibre and legumes): The Singapore Chinese Health Study (1993-2017). Quartiles of energy-adjusted food intake Q1 Q2 Q3 Q4 p for trend 1 Total fibre Median, g/day 8.55 9.43 12.19 17.70 Cases/ person-years 528/ 275,050 712/ 280,456 767/ 284,394 809/ 287,955 Multivariate Model 1 1.00 1.08 (0.96, 1.21) 1.12 (1.00, 1.26) 1.18 (1.05, 1.32) 0.003 Multivariate Model 2 1.00 1.06 (0.95, 1.19) 1.09 (0.97, 1.22) 1.11 (0.99, 1.24) 0.088 Legumes Median, g/day 0.11 0.43 2.11 7.01 Cases/ person-years 638/ 280,170 754/ 278,001 756/ 280,407 668/ 289,275 Multivariate Model 1 1.00 0.97 (0.87, 1.09) 0.95 (0.84, 1.06) 0.84 (0.76, 0.94) &lt;0.001 Multivariate Model 2 1.00 0.98 (0.87, 1.09) 0.94 (0.84, 1.06) 0.86 (0.77, 0.96) 0.004 Multivariate Model 3 1.00 0.98 (0.87, 1.09) 0.95 (0.84, 1.06) 0.86 (0.76, 0.96) 0.004 1 Linear trend was tested by assigning to participants the median value of the quartile and treating this as a continuous variable. 2 The grain products included noodles and pasta, rice, bread and pancakes, breakfast cereals, biscuits and crackers. Multivariate model 1: adjusted for age at interview, sex, year of interview, total energy intake, dialect, education level Multivariate model 2: model 1 plus BMI, sitting duration, sleep, physical activity, smoking, history of hypertension, diabetes, coronary artery disease and stroke. Multivariate model 3: model 2 plus grain products, legumes, nuts and seeds, soy food, fruits and vegetables. Q = quartile Disclosure of Interests: None declared.