The accuracy of the nonlinear one-dimensional (1-D) equations of pressure and flow wave propagation in Voigt-type visco-elastic arteries was tested against measurements in a well-defined experimental 1:1 replica of the 37 largest conduit arteries in the human systemic circulation. The parameters required by the numerical algorithm were directly measured in the in vitro setup and no data fitting was involved. The inclusion of wall visco-elasticity in the numerical model reduced the underdamped high-frequency oscillations obtained using a purely elastic tube law, especially in peripheral vessels, which was previously reported in this paper [Matthys et al., 2007. Pulse wave propagation in a model human arterial network: Assessment of 1-D numerical simulations against in vitro measurements. J. Biomech. 40, 3476–3486]. In comparison to the purely elastic model, visco-elasticity significantly reduced the average relative root-mean-square errors between numerical and experimental waveforms over the 70 locations measured in the in vitro model: from 3.0% to 2.5% false(p<0.012false) for pressure and from 15.7% to 10.8% false(p<0.002false) for the flow rate. In the frequency domain, average relative errors between numerical and experimental amplitudes from the 5th to the 20th harmonic decreased from 0.7% to 0.5% false(p<0.107false) for pressure and from 7.0% to 3.3% false(p<10−6false) for the flow rate. These results provide additional support for the use of 1-D reduced modelling to accurately simulate clinically relevant problems at a reasonable computational cost.

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Background and Objective Patients with fibromyalgia (FM) have a substantially reduced health-related quality of life (HRQoL). Their management should preferably focus on multidisciplinary nonpharmacological interventions. However, the long-term impact of such multicomponent therapies is not fully established. Waiting lists for patients seeking medical treatment are long, making individual-based approaches often unfeasible. The aim of our pragmatic study was to evaluate long-term HRQoL benefits of a comprehensive 8-week group-based multidisciplinary rehabilitation program focusing on patients' coping ability and self-care. Methods A total of 94 patients with clinically confirmed FM agreed to participate in this study. Before entering the program based on group-based cognitive behavioral therapy and graded activity training, patients completed questionnaires to screen for comorbidities. Health-related quality of life was assessed at the start, at 8 weeks, 6 months, and 1 year using the 36-Item Short-Form Health Survey instrument. Changes in HRQoL scores were analyzed according to linear mixed regression modeling. Results Baseline findings confirmed the substantially low physical and mental HRQoL in FM patients as well as high levels of depression, anxiety, and burnout. Only 2 patients left the program prematurely; 89% participated in the 1-year assessment. By the end of the program, HRQoL was significantly improved in all domains. This effect was maintained at 6 months and 1 year for all subscales. Changes at 1 year were greater in younger patients and those with depressive feelings before the start of treatment. Conclusions Our group-based program offered to FM patients proved successful with significant improvements in their HRQoL both in the short and long term.

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