Patellofemoral pain syndrome is associated with chronic disease and allergies in 60 997 distance runner race entrants: SAFER XXX Study

Abstract

Objective: Patellofemoral pain syndrome (PFPS) is a common running-related injury. Independent risk factors associated with PFPS have not been described in a large cohort of distance runners. Design: Descriptive, cross-sectional study. Setting: 21.1 and 56 km Two Oceans Marathon races (2012-2015). Participants: 60 997 race entrants. Assessment of risk factors: Participants completed a compulsory prerace medical screening questionnaire (history of PFPS in the past 12 months, n5362; no injury history, n 5 60 635). Selected risk factors associated with a history of PFPS were explored using univariate & multivariate analyses: demographics, training/running variables, history of chronic diseases (composite chronic disease score), and any allergy. Main OutcomeMeasures: Prevalence ratios (PRs, 95% confidence intervals). Results: Risk factors associated with PFPS (univariate analysis) were increased years of recreational running (PR 5 1.09; P 5 0.0107), older age (.50 years), and chronic diseases (PR . 2): gastrointestinal disease (PR 5 5.06; P , 0.0001), cardiovascular disease (CVD) (PR 5 3.28; P , 0.0001), nervous system/psychiatric disease (PR53.04; P,0.0001), cancer (PR52.83; P50.0005), risk factors for CVD (PR52.42; P, 0.0001), symptoms of CVD (PR 5 2.38; P 5 0.0397), and respiratory disease (PR 5 2.00; P , 0.0001). Independent risk factors (multivariate analysis) associated with PFPS (adjusted for age, sex, and race distance) were a higher chronic disease composite score (PR 5 2.68 increased risk for every 2 additional chronic diseases; P , 0.0001) and a history of allergies (PR 5 2.33; P , 0.0001). Conclusions: Novel independent risk factors associated with PFPS in distance runners are a history of multiple chronic diseases and a history of allergies. Identification of chronic diseases and allergies should be considered as part of the clinical assessment of a runner presenting with a history of PFPS.