Replacement Arthroplasty: Dougados M

Zochling J, van der Heijde D, Burgos-Vargas R, Collantes E, Davis JC, Dijkmans B, Dougados M, Géher P, Inman RD, Khan MA, Kvien TK, Leirisalo-Repo M, Olivieri I, Pavelka K, Sieper J, Stucki G, Sturrock RD, van der Linden S, Wendling D, Böhm H, van Royen BJ, Braun J, Anonymous00003, Anonymous00004. · Rheumazentrum-Ruhrgebiet, St Josefs-Krankenhaus, Landgrafenstr 15, 44652 Herne, Germany. · Ann Rheum Dis. · Pubmed #16126791 links to  free full text

Abstract: OBJECTIVE: To develop evidence based recommendations for the management of ankylosing spondylitis (AS) as a combined effort of the 'ASsessment in AS' international working group and the European League Against Rheumatism. METHODS: Each of the 22 participants was asked to contribute up to 15 propositions describing key clinical aspects of AS management. A Delphi process was used to select 10 final propositions. A systematic literature search was then performed to obtain scientific evidence for each proposition. Outcome data for efficacy, adverse effects, and cost effectiveness were abstracted. The effect size, relative risk, number needed to treat, and incremental cost effectiveness ratio were calculated. On the basis of the search results, 10 major recommendations for the management of AS were constructed. The strength of recommendation was assessed based on the strength of the literature evidence, risk-benefit trade-off, and clinical expertise. RESULTS: The final recommendations considered the use of non-steroidal anti-inflammatory drugs (NSAIDs) (conventional NSAIDs, coxibs, and co-prescription of gastroprotective agents), disease modifying antirheumatic drugs, treatments with biological agents, simple analgesics, local and systemic steroids, non-pharmacological treatment (including education, exercise, and physiotherapy), and surgical interventions. Three general recommendations were also included. Research evidence (categories I-IV) supported 11 interventions in the treatment of AS. Strength of recommendation varied, depending on the category of evidence and expert opinion. CONCLUSION: Ten key recommendations for the treatment of AS were developed and assessed using a combination of research based evidence and expert consensus. Regular updating will be carried out to keep abreast of new developments in the management of AS.

Zhang W, Doherty M, Arden N, Bannwarth B, Bijlsma J, Gunther KP, Hauselmann HJ, Herrero-Beaumont G, Jordan K, Kaklamanis P, Leeb B, Lequesne M, Lohmander S, Mazieres B, Martin-Mola E, Pavelka K, Pendleton A, Punzi L, Swoboda B, Varatojo R, Verbruggen G, Zimmermann-Gorska I, Dougados M, Anonymous00408. · Academic Rheumatology, University of Nottingham, UK. · Ann Rheum Dis. · Pubmed #15471891 links to  free full text

Abstract: OBJECTIVE: To develop evidence based recommendations for the management of hip osteoarthritis (OA). METHODS: The multidisciplinary guideline development group comprised 18 rheumatologists, 4 orthopaedic surgeons, and 1 epidemiologist, representing 14 European countries. Each participant contributed up to 10 propositions describing key clinical aspects of hip OA management. Ten final recommendations were agreed using a Delphi consensus approach. Medline, Embase, CINAHL, Cochrane Library, and HTA reports were searched systematically to obtain research evidence for each proposition. Where possible, outcome data for efficacy, adverse effects, and cost effectiveness were abstracted. Effect size, rate ratio, number needed to treat, and incremental cost effectiveness ratio were calculated. The quality of evidence was categorised according to the evidence hierarchy. The strength of recommendation was assessed using the traditional A-D grading scale and a visual analogue scale. RESULTS: Ten key treatment propositions were generated through three Delphi rounds. They included 21 interventions, such as paracetamol, NSAIDs, symptomatic slow acting disease modifying drugs, opioids, intra-articular steroids, non-pharmacological treatment, total hip replacement, osteotomy, and two general propositions. 461 studies were identified from the literature search for the proposed interventions of efficacy, side effects, and cost effectiveness. Research evidence supported 15 interventions in the treatment of hip OA. Evidence specific for the hip was strikingly lacking. Strength of recommendation varied according to category of research evidence and expert opinion. CONCLUSION: Ten key recommendations for the treatment of hip OA were developed based on research evidence and expert consensus. The effectiveness and cost effectiveness of these recommendations were evaluated and the strength of recommendation was scored.

Jordan KM, Arden NK, Doherty M, Bannwarth B, Bijlsma JW, Dieppe P, Gunther K, Hauselmann H, Herrero-Beaumont G, Kaklamanis P, Lohmander S, Leeb B, Lequesne M, Mazieres B, Martin-Mola E, Pavelka K, Pendleton A, Punzi L, Serni U, Swoboda B, Verbruggen G, Zimmerman-Gorska I, Dougados M, Anonymous00160. · Southampton General Hospital, Southampton S016 6YD, UK. · Ann Rheum Dis. · Pubmed #14644851 links to  free full text

Abstract: OBJECTIVES: To update the EULAR recommendations for management of knee osteoarthritis (OA) by an evidence based medicine and expert opinion approach. METHODS: The literature search and guidelines were restricted to treatments for knee OA pertaining to clinical and/or radiological OA of any compartment of the knee. Papers for combined treatment of knee and other types of OA were excluded. Medline and Embase were searched using a combination of subject headings and key words. Searches for those treatments previously investigated were conducted for January 1999 to February 2002 and for those treatments not previously investigated for 1966 to February 2002. The level of evidence found for each treatment was documented. Quality scores were determined for each paper, an effect size comparing the treatment with placebo was calculated, where possible, and a toxicity profile was determined for each treatment modality. RESULTS: 497 new publications were identified by the search. Of these, 103 were intervention trials and included in the overall analysis, and 33 treatment modalities were identified. Previously identified publications which were not exclusively knee OA in the initial analysis were rejected. In total, 545 publications were included. Based on the results of the literature search and expert opinion, 10 recommendations for the treatment of knee OA were devised using a five stage Delphi technique. Based on expert opinion, a further set of 10 items was identified by a five stage Delphi technique as important for future research. CONCLUSION: The updated recommendations support some of the previous propositions published in 2000 but also include modified statements and new propositions. Although a large number of treatment options for knee OA exist, the evidence based format of the EULAR Recommendations continues to identify key clinical questions that currently are unanswered.

Maillefert JF, Dougados M. · Department of Rheumatology, Dijon University Hospital, INSERM ERIT-M 0207, Department of Rheumatology, University of Burgundy, Hôpital Général, Dijon, France. · Rheum Dis Clin North Am. · Pubmed #14603586 No free full text.

Abstract: Each of the five sets of criteria for THA mentioned in this article should be regarded as preliminary. They require validation in future studies conducted in various cohorts of patients and in different countries. Moreover, a set of generally accepted criteria is badly needed. The number of proposed sets of criteria listed in this article indicates clearly that no consensus presently exists with respect to the optimal time for a patient who has hip OA to undergo THA.

Maillefert JF, Gueguen A, Nguyen M, Berdah L, Lequesne M, Mazières B, Vignon E, Dougados M. · René Descartes University, Cochin Hospital, Institut de Rhumatologie, Paris, France. · Rheumatology (Oxford). · Pubmed #11886961 links to  free full text

Abstract: OBJECTIVE: To determine a cut-off point above which a change in joint space width (JSW) could be considered as relevant in patients with hip osteoarthritis (OA) on the basis of predicted need for subsequent total hip arthroplasty (THA). METHODS: A multicentre, prospective, longitudinal, 5-yr follow-up study was performed. A pelvic radiograph was obtained at entry and after 1 and 2 yr. For each film, the narrowest JSW was measured using a 0.1 mm graduated magnifying glass. The absolute and relative differences between baseline and 1 and 2 yr of follow-up were calculated. We determined the cut-off points above which an absolute or relative decrease in JSW between baseline and 1 and 2 yr of follow-up could be considered relevant on the basis of the predicted need for THA during the remaining years of the study. The need for THA was categorized as 'yes' or 'no'. Thereafter, for each observed change in JSW (0.1 per 0.1 mm or 1% per 1%), the sensitivity and specificity for subsequent THA were calculated. The choice of cut-off was based on maximal sensitivity and specificity, using the graphic representation of correct classification probabilities. In this way it was possible to obtain the best measured JSW threshold with maximal true positive and minimal false positive results. RESULTS: A total of 423 and 385 patients met the criteria for analysis using the decrease in JSW between baseline and 1 and 2 yr respectively. The best cut-off points were absolute decreases in JSW of 0.2 and 0.4 mm and relative decreases in JSW of 15 and 20% after 1 and 2 yr respectively, with corresponding ranges of sensitivity and specificity of 68-75 and 67-78%. CONCLUSION: This work determined the cut-off above which a change in JSW could be considered clinically relevant in patients with hip OA, on the basis of predicted subsequent need for THA. For validation, similar studies should be conducted in other countries with different health-care systems.

Dougados M, Gueguen A, Nguyen M, Berdah L, Lequesne M, Mazieres B, Vignon E. · Institut de Rhumatologie, Hôpital Cochin, Paris, France. · J Rheumatol. · Pubmed #10229407 No free full text.

Abstract: OBJECTIVE: To assess if total hip arthroplasty (THA) is a valid outcome measure of hip osteoarthritis (OA), in respect to clinical and radiological assessments. METHODS: A prospective 3 year study of patients who had painful hip OA with an initial radiographic joint space width > or =1 mm at the narrowest point. Dependent variable was THA. Patient data including body mass index, OA structural severity by radiograph, OA symptomatic severity (pain, function), and OA localization were recorded at entry. Pelvic radiographs were obtained before THA, when available, and once yearly during the study. RESULTS: During the study 106 of 506 patients underwent THA. Risk was estimated (Kaplan-Meier method) to be 8+/-1, 16+/-2, and 23+/-2% after 1, 2, and 3 years, respectively. Factors predisposing to requirement for surgery were: age > or =70 years, female sex, superolateral migration of the femoral head, joint space width <2 mm, Kellgren-Lawrence grade > or =3, pain (visual analog scale) > or =50 mm, and Lequesne index > or =10 with a relative risk of 1.65, 1.71, 1.96, 1.85, 1.89, 1.86, and 2.59, respectively. Mean change in joint space width was 0.22+/-0.50 vs 0.97+/-1.35 mm/year in patients without and with THA, respectively (p<0.0001). Changes in radiological joint space width during the first year were highly predictive of requirement for THA during the 2 following years (risk of 5, 13, 25, and 79% in patients with a radiological joint space width worsening during the first year of 0, < or =25, >25 and < or =50, and >50%, respectively). CONCLUSION: These data suggest that THA could be considered as a valid outcome measure in OA. However, further studies should be conducted in other countries with different health care systems to evaluate the inter-country reliability of this measurement.

Gossec L, Hawker G, Davis AM, Maillefert JF, Lohmander LS, Altman R, Cibere J, Conaghan PG, Hochberg MC, Jordan JM, Katz JN, March L, Mahomed N, Pavelka K, Roos EM, Suarez-Almazor ME, Zanoli G, Dougados M. · Medicine Faculty, Paris 5 René Descartes University; AP-HP, Cochin Hospital, Department of Rheumatology B, Paris, France. · J Rheumatol. · Pubmed #17552070 No free full text.

Abstract: OBJECTIVE: Time to theoretical indication of joint replacement surgery has been proposed as a primary outcome for potential structure-modifying interventions for osteoarthritis (OA). The objectives of this OMERACT/OARSI Working Group were to identify pain, physical function, and structure states that represent the progression from early to late disease for individuals with OA of the hip and knee, and to create a composite measure of these 3 domains to define states of OA severity and a surrogate measure of "need for joint replacement surgery." METHODS: For pain, focus groups and one-on-one interviews were used. For function, Rasch analysis was performed on existing indices the Hip Dysfunction and Osteoarthritis Outcome Score (HOOS) and the Knee injury and Osteoarthritis Outcome Score (KOOS), each of which subsumes the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) questions. For structure, a comparison of existing indices (Kellgren-Lawrence, OARSI stages, and joint space width) was performed for the hip and the knee. RESULTS: For pain, key features of pain that are most distressing to people with OA from early to late disease were identified. For function, the reduction of the number of items based on the existing indices continues. For structure, the analysis is also ongoing. CONCLUSION: Preliminary results were presented at OMERACT 8; the final objective will be to combine the 3 domains (pain, function, and structure) and to create a composite index that could define states of severity and "need for total joint replacement," which could be used to evaluate treatment response to disease-modifying drugs in OA clinical trials.

Maillefert JF, Hawker GA, Gossec L, Mahomed NN, Lohmander S, Dieppe PA, Zanoli G, Hochberg MC, Dougados M, Anonymous00375. · Dijon University Hospital and INSERM/ERIT-M 0204, University of Burgundy, Dijon, France. · J Rheumatol. · Pubmed #16331784 No free full text.

Abstract: Interest has grown in using the requirement of total joint replacement (TJR) as a "hard" outcome measure. Limitations exist, however, in the use of such an outcome, in particular the variability in the decision to perform surgery, length of surgical waiting lists, and sensitivity to change. This special interest group is exploring ways of retaining the clinical relevance of TJR but overcoming the problems--2 alternative outcomes are being considered: "time to physician's decision to recommend surgery" and "time to fulfilling criteria for total joint replacement."

Mazières B, Garnero P, Guéguen A, Abbal M, Berdah L, Lequesne M, Nguyen M, Salles JP, Vignon E, Dougados M. · Department of Rheumatology CHU Rangueil 1, avenue Jean-Poulhès, Toulouse 31059, France. · Ann Rheum Dis. · Pubmed #16322084 links to  free full text

Abstract: OBJECTIVE: To determine whether systemic markers of bone, cartilage, and synovium can predict structural progression of osteoarthritis (OA). METHODS: Patients with painful hip OA were treated with diacerein or placebo in a multicentre, prospective, double blind, 3 year follow up trial. The following information was collected at entry: demographics, characteristics of hip OA, and 10 markers: N-propeptides of collagen types I and III, cartilage oligomeric matrix protein, YKL-40, hyaluronan (sHA), matrix metalloproteinases-1 and -3, C reactive protein, C-terminal crosslinking telopeptides of collagen types I and II (uCTX-II). Radiographs were obtained at entry and every year. Structural progression was defined as a joint space decrease > or =0.5 mm or requirement for total hip replacement. Grouped survival analysis was performed with time to structural progression as dependent variable, and clinical data, radiographic findings, treatment groups (diacerein versus placebo), and markers as explanatory measures. RESULTS: In the 333 patients in whom all markers were measured, high functional impairment, a joint space width <2 mm, and lateral migration of the femoral head at baseline increased the risk of progression, but diacerein had a protective effect (relative risk = 0.75; 95% confidence interval (CI) 0.54 to 0.96). In addition, patients in whom uCTX-II and sHA were in the upper tertile had a relative risk of progression of 3.73 (95% CI 2.48 to 5.61) compared with patients with markers in the two lower tertiles. CONCLUSION: In this large cohort, combined measurements of uCTX-II and sHA were a new predictor of the structural progression of hip OA.

Gossec L, Tubach F, Baron G, Ravaud P, Logeart I, Dougados M. · Service de Rhumatologie B, Hôpital Cochin, 27, rue du Faubourg Saint-Jacques, 75014 Paris, France. · Ann Rheum Dis. · Pubmed #15640268 links to  free full text

Abstract: OBJECTIVES: To determine the 2 year total hip replacement (THR) rate and to identify factors predictive of THR due to primary osteoarthritis (OA). METHODS: A 2 year prospective cohort study. Inclusion criteria were primary hip OA, with a history of pain for 6 months, and patients' pain assessment of > or =30 mm on a visual analogue scale (0-100 mm). Predictive factors of THR were identified by univariate then multivariate analysis using logistic regression. Potential predictors considered were demographic, radiographic (localisation and severity of OA), and patients' assessment of symptomatic severity of OA. RESULTS: Of the 741 patients enrolled, 505 (68.2%) patients, mean (SD) age 64.0 (10.1) years, mean (SD) disease duration 4.7 (5.2) years, had complete 2 year data. There was no difference between the completer and non-completer groups. During follow up, 189/505 (37.4%) patients had a first THR. By multivariate analysis, predictors of THR were Kellgren-Lawrence radiographic grade (grade III: odds ratio (OR) = 3.3 (95% confidence interval (95% CI) 1.7 to 6.4); grade IV: OR = 5.3 (95% CI 2.6 to 10.8)), high mean patient global assessment during the first 6 months (OR = 2.2 (95% CI 1.4 to 3.2)), and previous non-steroidal anti-inflammatory drug (NSAID) intake (OR = 1.5 (95% CI 1.0 to 2.4)). For two of these factors together, OR = 3.0 (95% CI 1.6 to 5.9), for three factors together, OR = 5.6 (95% CI 2.6 to 12.2). CONCLUSION: The 2 year rate of THR was high in this group of patients with painful hip OA: 37.4%. Radiological grade, mean patient global assessment, and the need for NSAIDs were predictive of THR.

Boutron I, Poiraudeau S, Ravaud P, Baron G, Revel M, Nizard R, Dougados M, Ravaud JF. · National Institute of Statistics and Economic Studies (INSEE), Paris, France. · J Rheumatol. · Pubmed #15088304 No free full text.

Abstract: OBJECTIVE: To describe and compare participation restrictions and environmental factors of persons with and without hip or knee arthroplasty in a national community based survey: the Handicap, Disability, Dependence Survey. METHODS: During the 1999 French Census, a screening questionnaire was proposed to 417,500 persons, for which the response rate was 86%. A stratified random sample with an overrepresentation of disabled persons was performed to constitute the selected population. A computer assisted interview was proposed to 21,760 persons, with a 78% response rate. Chronic conditions, impairment, disability, participation restrictions, and the description of environmental factors were ascertained from the subjects' reports. RESULTS: The hip and knee arthroplasty group was estimated at 691,000 persons in the French population. Although reporting a higher level of disability, this population did not report more participation restrictions than the general population in terms of their economic situation, housing, social relationships, and holidays. Moreover, when comparing environmental factors, this population reported better housing accessibility, more assistive devices (OR 5.2, 95% CI 3.7-7.2), specific fittings (OR 2.9, 95% CI 2.0-4.2), and helpers (OR 1.8, 95% CI 1.3-2.5). These environmental factors may have compensated for the higher level of disability. Nevertheless, individuals with hip and knee arthroplasty reported more disadvantages when moving within their environment (OR 2.1, 95% CI 1.5-2.9). CONCLUSION: This study provides a detailed description based on a national random sample of participation restrictions and environmental factors of adults with hip and knee arthroplasty.

Maillefert JF, Gueguen A, Monreal M, Nguyen M, Berdah L, Lequesne M, Mazieres B, Vignon E, Dougados M. · Institut de Rhumatologie, René Descartes University, Cochin Hospital, Paris, France. · Ann Rheum Dis. · Pubmed #12972469 links to  free full text

Abstract: OBJECTIVE: To evaluate sex differences in the clinical and structural presentation, and natural history of hip OA. METHODS: A multicentre, prospective, longitudinal, five year follow up study of 508 patients (302 women, 206 men, mean age 63 (7) years) with painful hip OA. Data collected were baseline demographics, symptomatic, therapeutic, and structural variables; symptomatic variables and changes in joint space width (JSW) during the first year's follow up; requirement for total hip arthroplasty (THA) between the end of the first and fifth years. Statistical analysis: evaluation of sex differences (a) at baseline, in the main characteristics of hip OA using multivariate logistic regression; (b) during the first year of follow up, in the radiological progression of the disease; (c) during the five years of follow up, in the requirement for THA using Kaplan-Meier curves and the log rank test, and of the parameters related to THA, using a multivariate Cox analysis. RESULTS: At entry, women presented more frequently than men with polyarticular OA (mean (SD) articular score 306 (162) v 235 (127)), and superomedial migration of the femoral head (40% v 19%), and had more severe symptomatic disease (patient's overall assessment 46 (23) v 40 (26)). The change in JSW did not differ between women and men after one year, but a greater proportion of women had rapid structural progression (OR=2.34, 95% CI 1.1 to 5.2). THA was performed more often in women. Multivariate analysis suggested that the decision to perform surgery was related more closely to the symptomatic and structural severity of the disease than to the sex of the patient. CONCLUSION: Hip OA in women is more frequently part of a polyarticular OA, and displays greater symptomatic and structural severity.

Boutron I, Poiraudeau S, Ravaud JF, Baron G, Revel M, Nizard R, Dougados M, Ravaud P. · Département de Médecine Physique et de Réadaptation, Hôpital Cochin (AP-HP), Université R Descartes, 75014 Paris, France. · Ann Rheum Dis. · Pubmed #12860730 links to  free full text

Abstract: OBJECTIVES: To compare levels of disability of people with and without hip and knee arthroplasty in a random national sample. METHODS: In 1999 a screening questionnaire to classify people into groups of increasing probabilities of disability was sent to 417 500 people; response rate 86%. The study population was obtained by a stratified randomisation, with a high sampling rate for the most severely disabled group and a minimum sampling rate for people without daily living restrictions. A computer assisted interview to assess levels of disability, dependence, and handicap was given to 21 760 people; response rate 78%. A weighting factor was applied to obtain estimates representative of the French population. The presence of chronic conditions, impairments, and disability was ascertained from the subjects' reports. RESULTS: The hip and knee arthroplasty group comprised 815 subjects in the sample, indicating an estimated 691 000 subjects (95% confidence interval (CI) 597 000 to 785 000) in the French non-institutionalised population. The prevalence of arthroplasty is estimated at 1.2%. After adjustments for confounding factors, activity limitations were greater among subjects with arthroplasty for the following activities: climbing stairs (odds ratio (OR)=4.0, 95% CI 2.8 to 5.8); walking distance (OR=3.4, 95% CI 2.5 to 4.6 for a walking distance less than 500 m); bending forward (OR=3.2, 95% CI 2.2 to 4.7); cutting toenails (OR=2.8, 95% CI 1.9 to 3.9); carrying (OR=2.6, 95% CI= 1.8 to 3.8); shopping (OR=2.1, 95% CI 1.5 to 2.9). CONCLUSIONS: This study would be useful to policy-makers considering population strategies for managing disabling arthritis.

Fardet L, Messow M, Maillefert JF, Dougados M. · Université René Descartes, Hôpital Cochin, Assistence Publique, Hôpitaux de Paris, Rheumatology B Department, Paris, France. · Clin Exp Rheumatol. · Pubmed #12673884 No free full text.

Abstract: OBJECTIVE: To evaluate the natural history of shoulder osteoarthritis (OA), in particular the requirement for arthroplasty over time, and to determine the potential predisposing factors for such arthroplasty. METHODS: In- and out-patients with the diagnosis of OA of the shoulder seen between January 1990 and December 1994 were contacted by mail or telephone in 2000. Evaluation at the time of diagnosis: demographics, clinical and radiological data were evaluated at the time of diagnosis. The follow-up evaluation consisted of a questionnaire sent to each patient inquiring whether they had had recourse to shoulder arthroplasty and, if not, evaluated their willingness regarding this surgical approach. For the statistical analysis the requirement for arthroplasty over time was evaluated using the Kaplan-Meier technique. Potential factors predisposing to arthroplasty were determined using a Cox-model analysis. RESULTS: The questionnaire was answered by 72 of the 86 contacted patients. No difference was observed in clinical and radiological variables at the time of diagnosis between responders and non-responders. The requirement for arthroplasty was low (respectively 5% and 13%, 5 and 10 years following the onset of the symptoms). Nearly half of the patients who had not undergone surgery thought that arthroplasty would have been the treatment of choice to improve their quality of life since more than one year at the time of completing the questionnaire. Two variables were picked up in the Cox analysis, with a probability of shoulder replacement higher in patients with concomitant osteonecrosis of the humeral head (p = 0.02) and a non-eccentric glenohumeral OA (p = 0.011). CONCLUSION: The low percentage of patients with arthroplasty over time, together with patient perception, suggest underuse of this surgical approach in shoulder OA.

Dougados M. · Université René-Descartes Hôpital Cochin 27, rue du Faubourg-Saint-Jacques, 75014 Paris. · Rev Prat. · Pubmed #11949491 No free full text.

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Maillefert JF, Gueguen A, Nguyen M, Berdah L, Lequesne M, Mazieres B, Vignon E, Dougados M. · Institute of Rheumatology, René Descartes University, Cochin Hospital, Paris, France. · J Rheumatol. · Pubmed #11838855 No free full text.

Abstract: OBJECTIVE: We propose a composite index for considering total hip arthroplasty (THA) in hip osteoarthritis (OA). METHODS: We carried out a 3 year longitudinal study of patients with painful hip OA from 137 centers. Clinical data were collected at baseline and every 3 months; radiographs were taken at entry and each year. The decision to have surgery was made by the patient, the rheumatologist, and the surgeon, with no reference to outcome measures. Statistical analysis included discrete Cox analysis with time dependent covariates, on 3 month interval grouped data. The dependent variable was THA during the 3 months following the evaluated visit. Time dependent covariates collated at each evaluated visit included radiological joint space width (JSW), percentage decrease in JSW during the year preceding, patient's global assessment. Lequesne index, pain, and nonsteroidal antiinflammatory drug and analgesic intake. We compared 2 analyses differing in symptomatic variables entered: values obtained at a single time point vs mean values between 2 visits at a 3 month interval. Selection of the index was based on the best combination of variables to predict occurrence of THA. RESULTS: Of the 508 patients recruited for study, 42 were excluded. During the 3 year followup, 75 patients underwent THA. Symptomatic, therapeutic, and radiological variables were included in the index resulting from the 2 analyses. Based on the selected cutoff, the positive and negative predictive values for occurrence of THA in the 2 years following were 54.3 and 90.6%, respectively (single point model), and 52.9 and 86.7%, respectively (model using mean values of symptomatic variables between 2 visits). CONCLUSION: The poor positive predictive value of the composite indices obtained in this study suggests that there are other unmeasured factors determining access to surgery. On the other hand, the high negative predictive values suggest that these composite measures should be used by clinicians to determine which patients should not be referred to THA.