title: Defining hip pain trajectories in early symptomatic hip osteoarthritis--5 year results from a nationwide prospective cohort study (CHECK).
abstract: OBJECTIVE
  To define distinct hip pain trajectories in individuals with early symptomatic hip osteoarthritis (OA) and to determine risk factors for these pain trajectories.
  
  
  METHODS
  Data were obtained from the nationwide prospective Cohort Hip and Cohort Knee (CHECK) study. Participants with hip pain or stiffness and a completed 5-year follow-up were included. Baseline demographic, anamnestic, physical examination characteristics were assessed. Outcome was annually assessed by the Numeric Rating Scale (NRS) for pain. Pain trajectories were retrieved by latent class growth analysis (LCGA). Multinomial logistic regression was used to calculate risk ratios.
  
  
  RESULTS
  545 participants were included. Four distinct pain trajectories were uncovered by LCGA. We found significant differences in baseline characteristics, including body mass index (BMI); symptom severity; pain coping strategies and in criteria for clinical hip OA (American College of Rheumatology (ACR)). Lower education, higher activity limitation scores, frequent use of pain transformation as coping strategy and painful internal hip rotation were more often associated with trajectories characterized by more severe pain. No association was found for baseline radiographic features.
  
  
  CONCLUSIONS
  We defined four distinct pain trajectories over 5 years follow-up in individuals with early symptomatic hip OA, suggesting there are differences in symptomatic progression of hip OA. Baseline radiographic severity was not associated with the pain trajectories. Future research should be aimed at measuring symptomatic progression of hip OA with even more frequent symptom assessment.
authors: Department of General Practice, Erasmus MC, University Medical Center Rotterdam, The Netherlands. Electronic address: a.bastick@erasmusmc.nl.
authors: A N
authors: AN
authors: Bastick
authors: Department of General Practice, Erasmus MC, University Medical Center Rotterdam, The Netherlands. Electronic address: s.p.j.verkleij@gmail.com.
authors: S P J
authors: SP
authors: Verkleij
authors: Department of General Practice, Erasmus MC, University Medical Center Rotterdam, The Netherlands. Electronic address: j.damen@erasmusmc.nl.
authors: J
authors: J
authors: Damen
authors: Department of Rheumatology and Clinical Immunology, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: J.Wesseling@umcutrecht.nl.
authors: J
authors: J
authors: Wesseling
authors: Allied Health Care Center for Rheumatology and Rehabilitation (AHCRR), Groningen, The Netherlands. Electronic address: info@pcrr.nl.
authors: W K H A
authors: WK
authors: Hilberdink
authors: Department of General Practice, Erasmus MC, University Medical Center Rotterdam, The Netherlands. Electronic address: p.bindels@erasmusmc.nl.
authors: P J E
authors: PJ
authors: Bindels
authors: Department of General Practice, Erasmus MC, University Medical Center Rotterdam, The Netherlands. Electronic address: s.bierma-zeinstra@erasmusmc.nl.
authors: S M A
authors: SM
authors: Bierma-Zeinstra
mesh_terms: D000223:Adaptation, Psychological; D000368:Aged; D015992:Body Mass Index; D018450:Disease Progression; D004522:Educational Status; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000150:complications* / Q000000981:diagnostic imaging; D010146:Pain / Q000175:diagnosis / Q000209:etiology* / Q000523:psychology; D010147:Pain Measurement / Q000379:methods; D011379:Prognosis; D011446:Prospective Studies; D011859:Radiography / Q000379:methods; D012307:Risk Factors; D012720:Severity of Illness Index
keywords: Hip osteoarthritis; Hip pain; Pain trajectories; Prediction