[Pain trajectories in early symptomatic knee osteoarthritis]. / Pijnbeloop bij vroeg-symptomatische knieartrose.

DESIGN: Retrospective cohort study. METHOD: We obtained data for this study from the 'Cohort Hip and Cohort Knee' (CHECK) study. Participants who presented with knee osteoarthritis at baseline were included. We assessed baseline patient parameters such as demographics, anamnesis and physical examination measurements. Pain outcome measure was assessed annually using a numeric rating scale. Different pain trajectories were defined by latent class growth analysis. Multinomial logistic regression was used to calculate relative risk ratios. RESULTS: In total, 705 participants were included. Six distinct pain trajectories were identified with favourable and unfavourable courses. We found significant differences in baseline characteristics between the different pain trajectories, including BMI; symptom severity; and pain coping strategies. Higher BMI, lower education, presence of co-morbidities, higher activity limitation scores and joint space tenderness were more often associated with trajectories characterized by more pain at first presentation and pain progression. No association was found for baseline radiographic features. CONCLUSION: We defined six distinct pain trajectories in individuals with early symptomatic knee osteoarthritis. Our results can help physicians identify those patients that require more frequent monitoring compared patients for whom a watch-and-wait policy seems justifiable. In general practice, radiography does not provide added value to the follow-up of early symptomatic knee osteoarthritis patients.

Defining hip pain trajectories in early symptomatic hip osteoarthritis--5 year results from a nationwide prospective cohort study (CHECK).

OBJECTIVE: To define distinct hip pain trajectories in individuals with early symptomatic hip osteoarthritis (OA) and to determine risk factors for these pain trajectories. METHOD: 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. CONCLUSION: 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.

NSAIDs vs acetaminophen in knee and hip osteoarthritis: a systematic review regarding heterogeneity influencing the outcomes.

OBJECTIVE: To identify sources of heterogeneity (statistical, methodological, and clinical) in studies evaluating non-steroidal anti-inflammatory drugs (NSAIDs) vs acetaminophen in patients with knee and hip osteoarthritis (OA) to elucidate variations in outcomes. METHOD: A database search (1966 to January 2010) was made for (randomized) controlled trials ((R)CTs) comparing NSAIDs vs acetaminophen in knee and hip OA. Extracted data included baseline demographic/clinical characteristics, outcomes at follow-up, and characteristics of study design. Heterogeneity was examined with subgroup analyses by exploring changes in effect size and with I(2) of Higgins. Pain measures were expressed as standardized mean differences. RESULTS: 15 RCTs, including 21 comparisons of NSAIDs and acetaminophen were included. Statistical heterogeneity was absent (Cochran's Q-test=14.11; I(2)=0; P=0.78). Moderate clinical heterogeneity was found for comparisons which included both hip and knee OA vs knee OA only (I(2)=51; P=0.09). NSAIDs seemed slightly more effective than acetaminophen if more patients with hip OA were included. However, the pooled effect sizes of comparisons with knee OA vs both knee and hip OA are equal. Low clinical heterogeneity was found for comparisons with low dosage of acetaminophen, normal dosage of NSAIDs, and moderate pain intensity at baseline. Low methodological heterogeneity was found for comparisons with a short duration. CONCLUSION: Future trials should present the results of hip and knee OA separately, as moderate clinical heterogeneity was found. There might be differences in effectiveness of NSAIDs vs acetaminophen in patients with hip vs knee OA. No significant methodological and statistical heterogeneity was found in studies evaluating NSAIDs vs acetaminophen.