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Background: While it is known that obesity increases the risk for cardiovascular disease (CVD), there has been no clear investigation into the effect an obesogenic diet exerts onto circulating platelets. As platelets are the critical actors in the formation of occlusive clots that manifest as a myocardial infarction or stroke, it is pertinent to establish any potential link between obesity and platelet activity. Methods: To examine the effect of a Western diet on baseline platelet activity, male C57BL6/J mice were fed either a control (10% fat, 7% sucrose, 0.3% salt Research Diets Inc. D12450J) or Western (40% fat, 30% sucrose, 8% salt Research Diets Inc. D06111701) diet ad libitum for 20 weeks beginning at the time of weaning. At 12, 16 and 20 weeks after beginning diet administration whole blood was collected via the retro-orbital sinus. Blood was used to generate platelet rich plasma (PRP) which was stimulated with collagen (20mg/ml) prior to staining for flow cytometry analysis. Flow cytometry staining utilized antibodies to recognize the platelet receptors GPIbα, P-Selectin and the activated form of integrin αIIbβ3 (JON/A). Additionally, body composition was likewise determined at these time points using Echo-MRI while bodyweight was measured weekly. Results: Western diet fed mice gained slightly more weight than control mice and had a higher percentage of body fat (measured by EchoMRI). Surprisingly, the two groups differed in GPIbα and activated αIIbβ3 expression on circulating platelets at all three observed time points. Specifically, platelets from control-fed mice displayed significantly higher GPIbα expression throughout the study while Western diet fed animals had higher levels of activated αIIbβ3. There was no difference in platelet expression of P-Selectin between the groups at any time point. Conclusions: Platelet activation is not a binary process where platelets display a definitive “active” or “inactive” phenotype. Though terminal platelet activation elicits de-granulation and an increase in P-Selectin expression, the spectrum of platelet stimulation preceding this is marked by variable incidences of integrin activation and GPIbα shedding. Here we demonstrate proof of principle that dietary factors, such as the consumption of a Western diet, can facilitate early changes to the stimulation pattern of circulating platelets which is then maintained long-term. While the consequence of this altered platelet stimulation profile is unknown with regards to the pathways of hemostasis and thrombosis, further investigations of downstream signaling and amplification pathways are needed. Funding: Arkansas Children's Research Institute/Arkansas Bioscience Institute Postgraduate Fellowship: AWD-037176 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

BACKGROUND Hydroxychloroquine (HCQ) is commonly used for patients with autoimmune conditions. Long-term use of HCQ can cause retinal toxicity, but this risk can be reduced if high doses are avoided. OBJECTIVE We developed and piloted an electronic health record–based dashboard to improve the safe prescribing of HCQ within the Veterans Health Administration (VHA). We observed pilot facilities over a 1-year period to determine whether they were able to improve the proportion of patients receiving inappropriate doses of HCQ. METHODS Patients receiving HCQ were identified from the VHA corporate data warehouse. Using PowerBI (Microsoft Corp), we constructed a dashboard to display patient identifiers and the most recent HCQ dose and weight (flagged if ≥5.2 mg/kg/day). Six VHA pilot facilities were enlisted to test the dashboard and invited to participate in monthly webinars. We performed an interrupted time series analysis using synthetic controls to assess changes in the proportion of patients receiving HCQ ≥5.2 mg/kg/day between October 2020 and November 2021. RESULTS At the start of the study period, we identified 18,525 total users of HCQ nationwide at 128 facilities in the VHA, including 1365 patients at the 6 pilot facilities. Nationwide, at baseline, 19.8% (3671/18,525) of patients were receiving high doses of HCQ. We observed significant improvements in the proportion of HCQ prescribed at doses ≥5.2 mg/kg/day among pilot facilities after the dashboard was deployed (–0.06; 95% CI –0.08 to –0.04). The difference in the postintervention linear trend for pilot versus synthetic controls was also significant (–0.06; 95% CI –0.08 to –0.05). CONCLUSIONS The use of an electronic health record–based dashboard reduced the proportion of patients receiving higher than recommended doses of HCQ and significantly improved performance at 6 VHA facilities. National roll-out of the dashboard will enable further improvements in the safe prescribing of HCQ.

Objective We assessed implementation of the 10-item Patient-Reported Outcomes Measurement Information System (PROMIS) physical function form (PF-10a) in routine practice in a racially and ethnically diverse population with rheumatoid arthritis (RA). Objectives were to determine feasibility of implementing PF-10a in the electronic health record (EHR) and PF-10a validity and longitudinal responsiveness. Methods Clinical and demographic data were abstracted from EHRs for all RA patients seen at a university-based rheumatology clinic between February 2013 and February 2015. We evaluated floor and ceiling (edge) effects and construct validity of PF-10a in a subgroup of patients with Health Assessment Questionnaire (HAQ) scores (n = 189). We used linear mixed-effects models to assess responsiveness of PF-10a to longitudinal changes in the Clinical Disease Activity Index (CDAI) for patients in the entire clinical cohort, with both scores recorded on at least 2 encounters (n = 326). Results Half of the patients were nonwhite, and 15% were non-English speakers. Over a 2-year period, PF10a was successfully implemented; 97% of patients and 89% of encounters had at least 1 measurement performed. PF-10a had fewer ceiling (defined as best) effects than the HAQ (8% versus 22%), and convergent validity was high (r = −0.85). PF-10a was sensitive to expected differences (older versus younger patients, more versus less active disease). Longitudinal changes in PF-10a were highly associated with changes in the CDAI score (P

Objective High-expression alleles of macrophage migration inhibitory factor (MIF) are linked genetically to the severity of systemic lupus erythematosus (SLE). The U1 small nuclear RNP (snRNP) immune complex containing U1 snRNP and anti-U1 snRNP antibodies, which are found in patients with SLE, activates the NLRP3 inflammasome, comprising NLRP3, ASC, and procaspase 1, in human monocytes, leading to the production of interleukin-1β (IL-1β). This study was undertaken to investigate the role of the snRNP immune complex in up-regulating the expression of MIF and its interface with the NLRP3 inflammasome. Methods MIF, IL-1β, NLRP3, caspase 1, ASC, and MIF receptors were analyzed by enzyme-linked immunosorbent assay, Western blotting, quantitative polymerase chain reaction, and cytometry by time-of-flight mass spectrometry (CytoF) in human monocytes incubated with or without the snRNP immune complex. MIF pathway responses were probed with the novel small molecule antagonist MIF098. Results The snRNP immune complex induced the production of MIF and IL-1β from human monocytes. High-dimensional, single-cell CytoF analysis established that MIF regulates activation of the NLRP3 inflammasome, including findings of a quantitative relationship between MIF and its receptors and IL-1β levels in the monocytes. MIF098, which blocks MIF binding to its cognate receptor, suppressed the production of IL-1β, the up-regulation of NLRP3, which is a rate-limiting step in NLRP3 inflammasome activation, and the activation of caspase 1 in snRNP immune complex-stimulated human monocytes. Conclusion The U1 snRNP immune complex is a specific stimulus of MIF production in human monocytes, with MIF having an upstream role in defining the inflammatory characteristics of activated monocytes by regulating NLRP3 inflammasome activation and downstream IL-1β production. These findings provide mechanistic insight and a therapeutic rationale for targeting MIF in subgroups of lupus patients, such as those classified as high genotypic MIF expressers or those with anti-snRNP antibodies.

Use of patient-reported outcome measures (PROs) in rheumatology research is widespread, but use of PRO data to evaluate the quality of rheumatologic care delivered is less well established. This article reviews the use of PROs in assessing health care quality, and highlights challenges and opportunities specific to their use in rheumatology quality measurement. It first explores other countries' experiences collecting and evaluating national PRO data to assess quality of care. It describes the current use of PROs as quality measures in rheumatology, and frames an agenda for future work supporting development of meaningful quality measures based on PROs.

The pathogenic hallmark of systemic lupus erythematosus is the autoimmune response against self nuclear Ags, including dsDNA. The increased expression of the proinflammatory cytokine IL-1β has been found in the cutaneous lesion and PBMCs from lupus patients, suggesting a potential involvement of this cytokine in the pathogenesis of lupus. IL-1β is produced primarily by innate immune cells such as monocytes and can promote a Th17 cell response, which is increased in lupus. IL-1β production requires cleaving pro–IL-β into IL-1β by the caspase-1–associated multiprotein complex called inflammasomes. In this study we show that self dsDNA induces IL-1β production from human monocytes dependent on serum or purified IgG containing anti–dsDNA Abs by activating the nucleotide-binding oligomerization domain–like receptor family pyrin domain–containing 3 (NLRP3) inflammasome. Reactive oxygen species (ROS) and K+ efflux were involved in this activation. Knocking down the NLRP3 or inhibiting caspase-1, ROS, and K+ efflux decreased IL-1β production. Supernatants from monocytes treated with a combination of self dsDNA and anti–dsDNA Ab+ serum promoted IL-17 production from CD4+ T cells in an IL-1β–dependent manner. These findings provide new insights in lupus pathogenesis by demonstrating that self dsDNA together with its autoantibodies induces IL-1β production from human monocytes by activating the NLRP3 inflammasome through inducing ROS synthesis and K+ efflux, leading to the increased Th17 cell response.

Background Treat-to-target is the recommended strategy for the management of rheumatoid arthritis (RA) and involves regular assessment of disease activity using validated measures and subsequent adjustment of medical therapy if patients are not in remission or low disease activity. Recommendations published in 2012 detailed the preferred disease activity measures but there have been few publications on implementation of disease activity measures in a real-world clinic setting. Methods Plan-Do-Study-Act (PDSA) methodology was used over two cycles with a goal of increasing provider measurement of disease activity during all RA patient visits. In PDSA cycle 1, we implemented a paper-based form to help providers assess disease activity in RA patients. PDSA cycle 2 included the creation of separate patient and physician forms for collection of information, identification of patients prior to their clinic visit and incorporation of medical assistants into the workflow. Results The first PDSA cycle improved the number of RA patients with documented disease activity measures from 24 % over a 4-week period, to an average of 44 % over an 8-week period. The second PDSA cycle showed a sustained and dramatic improvement, with 85 % of patients having a disease activity measure recorded over a 27-week period. Conclusions Implementation of disease activity measurement in a typical academic rheumatology clinic can be achieved by standardizing workflow using a simple paper form. Electronic supplementary material The online version of this article (doi:10.1186/s12913-016-1633-x) contains supplementary material, which is available to authorized users.

Many multicellular organisms produce two cell lineages: germ cells, whose descendants produce the next generation, and somatic cells, which support, protect, and disperse the germ cells. This germ-soma demarcation has evolved independently in dozens of multicellular taxa but is absent in unicellular species. A common explanation holds that in these organisms, inefficient intercellular nutrient exchange compels the fitness cost of producing nonreproductive somatic cells to outweigh any potential benefits. We propose instead that the absence of unicellular, soma-producing populations reflects their susceptibility to invasion by nondifferentiating mutants that ultimately eradicate the soma-producing lineage. We argue that multicellularity can prevent the victory of such mutants by giving germ cells preferential access to the benefits conferred by somatic cells. The absence of natural unicellular, soma-producing species previously prevented these hypotheses from being directly tested in vivo: to overcome this obstacle, we engineered strains of the budding yeast Saccharomyces cerevisiae that differ only in the presence or absence of multicellularity and somatic differentiation, permitting direct comparisons between organisms with different lifestyles. Our strains implement the essential features of irreversible conversion from germ line to soma, reproductive division of labor, and clonal multicellularity while maintaining sufficient generality to permit broad extension of our conclusions. Our somatic cells can provide fitness benefits that exceed the reproductive costs of their production, even in unicellular strains. We find that nondifferentiating mutants overtake unicellular populations but are outcompeted by multicellular, soma-producing strains, suggesting that multicellularity confers evolutionary stability to somatic differentiation.

We assessed implementation of the 10-item Patient-Reported Outcomes Measurement Information System (PROMIS) physical function form (PF-10a) in routine practice in a racially and ethnically diverse population with rheumatoid arthritis (RA). Objectives were to determine feasibility of implementing PF-10a in the electronic health record (EHR) and PF-10a validity and longitudinal responsiveness.Clinical and demographic data were abstracted from EHRs for all RA patients seen at a university-based rheumatology clinic between February 2013 and February 2015. We evaluated floor and ceiling (edge) effects and construct validity of PF-10a in a subgroup of patients with Health Assessment Questionnaire (HAQ) scores (n = 189). We used linear mixed-effects models to assess responsiveness of PF-10a to longitudinal changes in the Clinical Disease Activity Index (CDAI) for patients in the entire clinical cohort, with both scores recorded on at least 2 encounters (n = 326).Half of the patients were nonwhite, and 15% were non-English speakers. Over a 2-year period, PF10a was successfully implemented; 97% of patients and 89% of encounters had at least 1 measurement performed. PF-10a had fewer ceiling (defined as best) effects than the HAQ (8% versus 22%), and convergent validity was high (r = -0.85). PF-10a was sensitive to expected differences (older versus younger patients, more versus less active disease). Longitudinal changes in PF-10a were highly associated with changes in the CDAI score (P 0.0001).PF-10a was feasible to implement in a diverse RA population. It strongly correlates with the HAQ but has fewer ceiling effects and is responsive to changes in RA disease activity, suggesting its validity for use in routine clinical practice.

Background Physicians frequently differ in their treatment recommendations. However, few studies have examined the reasons underlying these differences. The objective of this study was to examine whether physicians vary in the importance they attach to specific adverse events for two treatment options found in recent randomized controlled trials to have equivalent efficacy and overall toxicity. Methods A Max-Diff survey was administered to physicians attending a national scientific conference to quantify the influence of 23 specific adverse events on decision making related to two treatment options for vasculitis. This approach was chosen because it results in greater item discrimination compared to rating scales. We used Hierarchical Bayes modeling to generate the relative importance score for each adverse event and examined the association between physicians’ characteristics and the five most influential factors. Results 118 physicians completed the survey. The mean age (SD) was 48 years (10); 68% were male and 81% reported spending the majority of time in clinical practice. There was significant variability in the ratings of the relative importance of all adverse events, except those that were mild and easily reversible. We found a positive correlation between increasing physician age with ratings of sepsis (r = 0.29, p = 0.002) and opportunistic infection (r = 0.23, p = 0.016), and an inverse association between age with progressive multifocal leukoencephalopathy (r = - 0.28, p = 0.003). Physician sex, work setting, location, and number of patients with vasculitis seen per year were not associated with the influence of specific adverse events on decision making. Conclusion Our findings demonstrate that physicians differ substantially in how they perceive the importance of specific adverse events which may help explain observed unwarranted variability in physicians’ recommendations in clinical practice. Further efforts are needed to ensure that the reasons underlying variability in physicians’ recommendations are transparent.

Common questions about lung function tests, including why perform these tests, when are they helpful, who can be tested, and which tests are most useful, are answered for the pediatrician. Tests presently used in clinical pulmonary laboratories are described.