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Objective: Sensing with capacitive electrodes is of interest for long-term, comfortable bio-potential measurements (e.g., ECG). However, due to the small body-to-electrode capacitance (C e ), the design of the associated front-end amplifier remains a challenge. Both voltage amplifiers (VA) and charge amplifiers (CA) can be employed. While basic comparisons of both typologies were done before, this paper extends the comparison to their responses to artifacts (caused by motion or interference). Further, a VA-CA-switchable amplifier is proposed, allowing to adapt the amplifier type to different situations, and enabling to estimate the body-to-electrode capacitance C e in a passive way. Methods: A VA-CA switchable amplifier was implemented in a 180 nm CMOS process. The responses to artifacts for VA and CA were studied by modelling, simulations and experiments using the custom IC. The proposed C e estimation method was validated by electrical tests and in-vivo tests. Results: VAs are less affected by C e variation artifacts, while CAs recover faster from triboelectricity artifacts. In a VA, these two artifacts are multiplicative and get modulated if they occur simultaneously, but in a CA they remain independent. Conclusion: The combined VA-CA amplifier has the potential for optimal amplifier selection according to the properties of the recorded signal, the value of C e and the actual presence of artifacts. Moreover, it can estimate C e without extra hardware. Significance: The proposed VA-CA switchable structure is superior to an individual VA or CA, thanks its adaptability to signal quality and artifacts, and it provides extra information on the body-to-electrode interface quality (C e ).

BACKGROUND Sepsis is one of the leading causes of death in the hospital. Several warning scores have been developed to categorize patients’ degrees of illness, with the purpose of recognizing sepsis development at an early stage and consequently reducing time before starting treatment. The most accurate classification method, known as the SOFA score, is developed for use in the intensive care unit (ICU). OBJECTIVE Sepsis is not exclusively developing in the ICU and may occur in any hospitalized patient. Therefore, a method for sepsis recognition outside the ICU is of major importance. METHODS Recently, the use of computational methods has been proposed for early sepsis prediction. Multiple sepsis classifiers have been devised using machine learning methods. We validated the linear classification model devised by Calvert et al. and improved upon it using a deep neural network trained on data from the MIMIC-III database. RESULTS The reference model based on Calvert et al. approach yielded an AUROC of 0.81 for a 3-hour prediction time. The deep neural network outperformed the linear model, reaching an AUROC of 0.85 for a 3-hour prediction time. CONCLUSIONS Our results are comparable to the high-resolution model derived by Nemati et al. yet using only 8 simple and commonly performed measurements, instead of the complex set of 65 measurements leveraged by Nemati et al. Therefore, sepsis prediction may also be viable in less monitored environments in the hospital, such as the general ward and the emergency room.

Early recognition of joint inflammation will increase treatment efficacy in rheumatoid arthritis (RA). Yet, conventional power Doppler (PD) ultrasound might not be sufficiently sensitive to detect minor inflammation. We investigated the sensitivity of high-frame rate Doppler, combined with singular value decomposition technique, to suppress tissue signals, for microvascular flow in a flow phantom setup and in a proof-of-principle study in healthy controls and in RA patients with different disease activities. In the flow phantom, minimal detectable flow velocity was a factor 3 lower with high-frame-rate PD than with conventional PD ultrasound. In the proof-of-principle study we detected a positive PD signal in all volunteers, diseased or healthy, with high-frame-rate PD ultrasound. We saw a gradual increase in PD signal in RA patients depending on disease activity. In conclusion, high-frame rate Doppler is more sensitive in detecting vascularisation than conventional PD ultrasound.

OBJECTIVE: . To compare the screening performance of the Psoriasis Epidemiology Screening Tool (PEST), Psoriatic Arthritis Screening and Evaluation (PASE) and Early Arthritis for Psoriatic Patients (EARP) questionnaires for detecting PsA among psoriasis patients in a primary care setting.METHODS: In a cross-sectional study, 473 primary care psoriasis patients at risk for PsA completed the PEST, PASE and EARP questionnaires and were clinically evaluated by a trained research nurse. A PsA case was defined by a rheumatologist according to the CASPAR criteria. Sensitivity and specificity were determined for the PEST and EARP cut-offs (⩾3) and the PASE cut-offs (⩾44 and ⩾47).RESULTS: PsA was diagnosed in 53 patients. The PEST had a sensitivity of 0.68 and a specificity of 0.71. The PASE was validated for two different cut-offs. The cut-off of 47 led to a sensitivity of 0.59 and a specificity of 0.66, whereas the lower cut-off of 44 led to a sensitivity of 0.66 and a specificity of 0.57. For the EARP we found a sensitivity of 0.87 with a specificity of 0.34.CONCLUSION: The PEST questionnaire has the most favourable trade-off between sensitivity and specificity to screen for PsA. However, as the prevalence of psoriasis and PsA is fairly low in primary care, screening only psoriasis patients with musculoskeletal complaints may be a better allocation of resources.

ObjectivesThe aim of this study is to evaluate the effectiveness of two tapering strategies after achieving controlled disease in patients with rheumatoid arthritis (RA), during 1 year of follow-up.MethodsIn this multicentre single-blinded (research nurses) randomised controlled trial, patients with RA were included who achieved controlled disease, defined as a Disease Activity Score (DAS) ≤ 2.4 and a Swollen Joint Count (SJC) ≤ 1, treated with both a conventional synthetic disease-modifying antirheumatic drugs (csDMARD) and a TNF inhibitor. Eligible patients were randomised into gradual tapering csDMARDs or TNF inhibitors. Medication was tapered if the RA was still under control, by cutting the dosage into half, a quarter and thereafter it was stopped. Primary outcome was proportion of patients with a disease flare, defined as DAS > 2.4 and/or SJC > 1. Secondary outcomes were DAS, European Quality of Life-5 Dimensions (EQ5D) and functional ability (Health Assessment Questionnaire Disability Index [HAQ-DI]) after 1 year and over time.ResultsA total of 189 patients were randomly assigned to tapering csDMARDs (n = 94) or tapering anti-TNF (n = 95). The cumulative flare rates in the csDMARD and anti-TNF tapering group were, respectively, 33 % (95% CI,24% to 43 %) and 43 % (95% CI, 33% to 53 % (p = 0.17). Mean DAS, HAQ-DI and EQ-5D did not differ between tapering groups after 1 year and over time.ConclusionUp to 9 months, flare rates of tapering csDMARDs or TNF inhibitors were similar. After 1 year, a non-significant difference was found of 10 % favouring csDMARD tapering. Tapering TNF inhibitors was, therefore, not superior to tapering csDMARDs. From a societal perspective, it would be sensible to taper the TNF inhibitor first, because of possible cost reductions and less long-term side effects.Trial registration numberNTR2754

textabstractObjective To estimate the prevalence of psoriatic arthritis (PsA) in primary care patients diagnosed as having psoriasis and to estimate the prevalence of musculoskeletal symptoms in psoriasis patients in primary care. Methods We conducted a cross-sectional study in adult primary care patients with psoriasis. Responding patients reporting pain in joints, entheses, or the lower back were interviewed by telephone to determine eligibility and, if eligible, were invited for clinical evaluation. During clinical evaluation, skin, nails, joints, and entheses were assessed. Additionally, ultrasound of the enthesis was performed by an independent trained examiner if a patient had at least 1 tender enthesis (determined by the Leeds Enthesitis Index and the Maastricht Ankylosing Spondylitis Enthesitis Score). Patients who fulfilled the Classification of Psoriatic Arthritis (CASPAR) Study Group criteria were classified as having PsA. Results We invited 2,564 psoriasis patients from databases of 97 participating general practitioners. Of 1,673 responders (65.2%), 841 (50.3%) were willing to participate. A total of 823 patients (32.1%) reported having musculoskeletal symptoms; 659 of these patients were determined to be eligible, 524 of whom were clinically evaluated. We identified 64 cases of established PsA and another 17 cases of newly diagnosed PsA, leading to a prevalence of 3.2% (95% confidence interval [95% CI] 2.5-3.9) among psoriasis patients in primary care. This prevalence would increase to 4.6% (95% CI 3.8-5.4) if PsA cases based on enthesitis were also taken into account. Conclusion Among psoriasis patients in primary care, the prevalence of PsA is conservatively estimated to be 3.2%, increasing to 4.6% if enthesitis is taken into account. The prevalence of musculoskeletal symptoms among psoriasis patients is comparable with the prevalence of musculoskeletal symptoms in the general population.

Background Sepsis is one of the leading causes of death in the hospital. Several warning scores have been developed to categorize patients’ degrees of illness, with the purpose of recognizing sepsis onset at an early stage and consequently reducing time before starting treatment. The most accurate classification method, known as the SOFA score, is developed for use in the intensive care unit (ICU). Objective Sepsis is not exclusively developing in the ICU and may occur in any hospitalized patient. Therefore, a reliable method for sepsis recognition using routinely gathered information from the general ward is of major importance. Methods Recently, the use of computational methods has been proposed for early sepsis prediction. Multiple sepsis classifiers have been devised using machine learning methods. We validated a linear classification model and improved upon it using a deep neural network trained on data from the MIMIC-III database. Results The reference model approach yielded an Area Under Precision-Recall Curve (AUPRC) of 0.45 for a 3-h prediction time. Our newly constructed deep neural network outperformed the reference model, reaching an AUPRC of 0.49 for a 3-h prediction time. These results demonstrate to be robust for multiple prediction times, utilizing different datasets and multiple sepsis criteria. Conclusions Our results are comparable to a high-resolution model, yet using only 8 simple and commonly performed measurements, instead of the complex set of dozens of measurements leveraged by other authors. Moreover, our method proves to adapt to different datasets and sepsis criteria, yielding a high accuracy. Therefore, sepsis onset prediction may also be viable in less monitored environments in the hospital, such as the general ward and the emergency room.

__Objective__ In this study we aimed to evaluate the effect of lowering the cut point of the 2010 criteria to identify more patients with RA among early inflammatory arthritis patients. __Methods__ We included early arthritis patients from the Rotterdam Early Arthritis Cohort with at least one joint with clinical synovitis and symptoms for

OBJECTIVES: Although RA patients achieve clinical remission, risk of flare still exists. Given the association between US synovitis and increased risk of flare, it is of clinical interest whether these patients report a different health status. Therefore, our aim was to evaluate the frequency of US remission in RA patients in clinical remission and to compare the health status of RA patients in clinical remission with those who were also in US remission.METHODS: In a prospective study, we included 89 RA patients (aged >17 years) treated with a synthetic DMARD and a TNF inhibitor who were in remission (DAS in 44 joints ⩽2.4 and swollen joint count ⩽1). Demographic characteristics, swollen and tender joints, laboratory variables, US (MCP2-5, PIP2-5, wrists and MTP2-5) and patient-reported outcomes (general health, functional ability, fatigue, depression and anxiety, pain and morning stiffness) were recorded at two consecutive visits (3 months apart). US remission was defined as grey scale grade ⩽1 and power Doppler = 0.RESULTS: At visit 1, 39% of patients were in US remission. At visit 2, 32% of patients were in US remission. At visit 1, functional ability (HAQ) was scored lower by patients in US remission (P = 0.029). At visit 2, HAQ scores were similar (P = 0.928). At visit 2, Hospital Anxiety and Depression Scale anxiety score and visual analog scale pain were significantly higher in patients in US remission. Similar levels were found for the other patient-reported outcomes.CONCLUSION: One-third of RA patients in clinical remission were in US remission. In our study population, we could not find a clear association between health status of RA patients and being in US remission.

Part of the psoriasis patients with musculoskeletal complaints will have inflammation of the entheses. Entheseal inflammation is difficult to assess by clinical examination only. Therefore, we aimed to determine the frequency of clinically relevant ultrasound inflammation at the most commonly assessed entheses (MASEI; Madrid Sonographic Enthesis Index) in primary care psoriasis patients with one or more tender entheses.Adult primary care psoriasis patients with musculoskeletal complaints (tender enthesis or arthritis at physical examination) had an ultrasound examination of seven entheses according to the MASEI. Clinically relevant ultrasound inflammation was defined as active inflammation on ultrasound in combination with at least one clinical feature at the same enthesis. Active ultrasound inflammation contained positive power Doppler signal or in case of the plantar aponeurosis increased thickness. Structural changes entailed calcifications, enthesophytes, increased thickness, hypoechogeneicity indicating irregular fibre structure and erosions. Clinically, an enthesis was scored positive by a tender enthesis at clinical examination, reported pain in the history or self-reported pain in the questionnaires.Of 542 primary care psoriasis patient, 111 patients had tender entheses and/or arthritis. These patients were both clinically and ultrasonographically evaluated. Active ultrasound inflammation accompanied with pain or tenderness at the enthesis was found in 36% of the patients (n=40). Most common were inflammation at the knee (n=11) and at the plantar aponeurosis (n=10). Structural changes were observed in 95% of the psoriasis patients independent of their clinical manifestation.We found concurrent presence of ultrasound inflammatory changes and clinical symptoms in 36% of the primary care psoriasis patients who had tenderness at one or more entheseal sites.

To estimate the prevalence of psoriatic arthritis (PsA) in primary care patients diagnosed as having psoriasis and to estimate the prevalence of musculoskeletal symptoms in psoriasis patients in primary care.We conducted a cross-sectional study in adult primary care patients with psoriasis. Responding patients reporting pain in joints, entheses, or the lower back were interviewed by telephone to determine eligibility and, if eligible, were invited for clinical evaluation. During clinical evaluation, skin, nails, joints, and entheses were assessed. Additionally, ultrasound of the enthesis was performed by an independent trained examiner if a patient had at least 1 tender enthesis (determined by the Leeds Enthesitis Index and the Maastricht Ankylosing Spondylitis Enthesitis Score). Patients who fulfilled the Classification of Psoriatic Arthritis (CASPAR) Study Group criteria were classified as having PsA.We invited 2,564 psoriasis patients from databases of 97 participating general practitioners. Of 1,673 responders (65.2%), 841 (50.3%) were willing to participate. A total of 823 patients (32.1%) reported having musculoskeletal symptoms; 659 of these patients were determined to be eligible, 524 of whom were clinically evaluated. We identified 64 cases of established PsA and another 17 cases of newly diagnosed PsA, leading to a prevalence of 3.2% (95% confidence interval [95% CI] 2.5-3.9) among psoriasis patients in primary care. This prevalence would increase to 4.6% (95% CI 3.8-5.4) if PsA cases based on enthesitis were also taken into account.Among psoriasis patients in primary care, the prevalence of PsA is conservatively estimated to be 3.2%, increasing to 4.6% if enthesitis is taken into account. The prevalence of musculoskeletal symptoms among psoriasis patients is comparable with the prevalence of musculoskeletal symptoms in the general population.

Introduction: In many patients with rheumatoid arthritis (RA) subclinical disease activity can be detected with ultrasound (US), especially using power Doppler US (PDUS). However, PDUS may be highly dependent on the type of machine. This could create problems both in clinical trials and in daily clinical practice. To clarify how the PDUS signal differs between machines we created a microvessel flow phantom.Methods: The flow phantom contained three microvessels (150, 1000, 2000 microns). A syringe pump was used to generate flows. Five US machines were used. Settings were optimised to assess the lowest detectable flow for each US machine.Results: The minimal detectable flow velocities showed very large differences between the machines. Only two of the machines may be able to detect the very low flows in the capillaries of inflamed joints. There was no clear relation with price. One of the lower-end machines actually performed best in all three vessel sizes.Conclusions: We created a flow phantom to test the sensitivity of US machines to very low flows in small vessels. The sensitivity of the power Doppler modalities of 5 different machines was very different. The differences found between the machines are probably caused by fundamental differences in processing of the PD signal or internal settings inaccessible to users. Machines considered for PDUS assessment of RA patients should be tested using a flow phantom similar to ours. Within studies, only a single machine type should be used.