Dietary Fiber Intake in Relation to Knee Pain Trajectory

Dai Z, Lu N, Niu J, Felson DT, Zhang Y · Arthritis Care & Research (Hoboken)

Group-based trajectory modelling split the cohort into four eight-year pain courses — no pain (34.5%), mild (38.1%), moderate (21.2%), severe (6.2%) — rather than comparing means. Highest versus lowest fibre quartile: OR 0.76 (95% CI 0.61-0.93) for belonging to the moderate-pain course and 0.56 (95% CI 0.41-0.78) for the severe-pain course, with grain fibre behaving the same way. The authors anchor the benefit around the recommended 25 g/day.

Population

4,470 people (8,940 knees) aged 45-79 with or at risk of knee OA, followed annually for 8 years

Intervention

Higher baseline dietary total or grain fibre intake

Comparator

Lowest quartile

Limitations

Same cohort and same baseline questionnaire as the incidence paper, so this is a second analysis rather than independent support. Trajectory membership is model-assigned. Fibre intake proxies for diet quality, activity and body weight.