Share of mean of total ambulatory care costs the year before TKR.

<p>HA group: patients who received at least one IA HA injection during their follow-up period, N-HA group: patients who received only CS as IA injections, TKR: total knee replacement, IA: intra-articular, HA: hyaluronic acid, CS: corticosteroids, SD: standard deviation. Visits to doctors include visits to rheumatologists, orthopedic surgeons, physicians specialized in physical medicine and rehabilitation or GPs.</p

Do intra-articular hyaluronic acid injections delay total knee replacement in patients with osteoarthritis – A Cox model analysis

<div><p>Due to the growing worldwide prevalence of knee osteoarthritis, the optimal management of this issue is critical for reducing its burden.</p><p>Objectives</p><p>This study aimed to describe patients treated for knee osteoarthritis between 2006 and 2013 in France and to compare the delay from diagnosis to total knee replacement between patients who received intra-articular hyaluronic acid injections and those who did not receive the injections. A second objective was to compare direct medical costs for ambulatory care between treatment groups.</p><p>Materials and methods</p><p>Patients were selected from a representative sample of the real world administrative claims database using an algorithm developed by experts from the scientific committee of the study. Data were matched with the medico-administrative database for hospital care. A Cox proportional hazards model was stratified for the treatment group and adjusted for available socio-demographic and medical covariates to compare restricted mean survival times at different time points (1, 3, 5 and 7.5 years) between groups. Costs were expressed in 2013 euros.</p><p>Results</p><p>A total of 14,782 patients were treated for knee osteoarthritis (67% women; mean age = 68 years). Among this population, 1,662 patients had total knee replacement (11.2%). At each time point, restricted mean survival time without total knee replacement was significantly higher (p-values<0.001) for hyaluronic acid group, from +51 to +217 days at 1 and 7.5 years, respectively. For the year preceding total knee replacement, the means for total direct medical costs were similar between groups, €744 vs €805 for treatment and control groups, respectively, (p-value = 0.104). Intra-articular injections accounted for less than 10% of the total costs.</p><p>Conclusion</p><p>This is the first retrospective longitudinal study involving knee osteoarthritis patients using medico-administrative databases in France. The results support the effectiveness of hyaluronic acid injections in delaying total knee replacement and show that patients treated with hyaluronic acid have similar direct medical costs for ambulatory care compared to patients treated with corticosteroids only.</p></div

Flow-chart of patients’ selection.

<p>IA: intra-articular, HA: hyaluronic acid, CS: corticosteroids, TKR: total knee replacement. HA group: patients who received at least one IA HA injection during their follow-up period, N-HA group: patients who received only CS as IA injections. The four specialists are rheumatologist, orthopedic surgeon, physical medicine and rehabilitation practitioner and general practitioner.</p

Kaplan-Meier curves of time without TKR for HA and N-HA groups.

<p>HA group: patients who received at least one IA HA injection during their follow-up period, N-HA group: patients who received only CS as IA injections, TKR: total knee replacement, IA: intra-articular, HA: hyaluronic acid, CS: corticosteroids.</p

Bivariate analysis of knee OA patients who had TKR.

<p>Bivariate analysis of knee OA patients who had TKR.</p

Hazard ratios of adjustment covariates from the stratified Cox model.

<p>Hazard ratios of adjustment covariates from the stratified Cox model.</p

Descriptive analysis of patients with knee OA.

<p>Descriptive analysis of patients with knee OA.</p

Annual incidence rates (per 100,000) of attempted and completed suicide reported to the French GPs between 2010 and 2021.

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Measures of restrictions against COVID-19 in France, March 2020-March 2022.

(PDF)</p