Determinants of health-related quality of life across the spectrum of connective tissue diseases using latent profile analysis: results from the LEAP cohort.

OBJECTIVES: Poor health-related quality of life (HRQoL) is well recognized in patients with CTD. We hypothesized that subgroups of patients across the spectrum of CTD experience different HRQoL patterns and aimed to determine patient-level characteristics associated with these different subgroups. METHODS: Using the eight continuous domains of the Medical Outcomes Study 36-item Short Form (SF-36) questionnaire we performed data-driven clustering to derive latent profiles (LPs) of patients with distinct HRQoL patterns. Multivariable ordinal logistic regression was used to determine patient-level characteristics associated with each HRQoL subgroup identified. RESULTS: A total of 309 CTD patients completed the SF-36 questionnaire. The most impaired SF-36 domains in each disease group were vitality, general health and bodily pain. The physical component of the SF-36 was consistently more impaired compared with the mental component, with similar scores across disease groups. Three LPs were identified with poor [n = 89 (29%)], average [n = 190 (61.4%)] and excellent [n = 30 (9.7%)] HRQoL. LPs were not associated with diagnostic grouping or autoantibody profiles. Black background [odds ratio (OR) 0.22 (95% CI 0.08, 0.63)], Indo-Asian background [OR 0.39 (95% CI 0.19, 0.78)], concomitant fibromyalgia [OR 0.40 (95% CI 0.20, 0.78)], sicca symptoms [OR 0.56 (95% CI 0.32, 0.98)] and multimorbidity [Charlson Comorbidity Index; OR 0.81 (95% CI 0.67, 0.97)] were associated with the 'poor' HRQoL LP. CONCLUSION: Distinct HRQoL subgroups exist that are not primarily driven by a specific diagnosis or autoantibody profiles. We identified a number of key demographic and clinical factors associated with poor HRQoL. These factors need to be addressed across the whole CTD spectrum as part of a holistic management approach aimed at improving overall patient outcomes.

Contact Ion Pairs in the Bulk Affect Anion Interactions with Poly(N-isopropylacrylamide).

Salt effects on the solubility of uncharged polymers in aqueous solutions are usually dominated by anions, while the role of the cation with which they are paired is often ignored. In this study, we examine the influence of three aqueous metal iodide salt solutions (LiI, NaI, and CsI) on the phase transition temperature of poly(N-isopropylacrylamide) (PNIPAM) by measuring the turbidity change of the solutions. Weakly hydrated anions, such as iodide, are known to interact with the polymer and thereby lead to salting-in behavior at low salt concentration followed by salting-out behavior at higher salt concentration. When varying the cation type, an unexpected salting-out trend is observed at higher salt concentrations, Cs+ > Na+ > Li+. Using molecular dynamics simulations, it is demonstrated that this originates from contact ion pair formation in the bulk solution, which introduces a competition for iodide ions between the polymer and cations. The weakly hydrated cation, Cs+, forms contact ion pairs with I- in the bulk solution, leading to depletion of CsI from the polymer-water interface. Microscopically, this is correlated with the repulsion of iodide ions from the amide moiety.

Translating research into clinical practice: quality improvement to halve non-adherence to methotrexate.

OBJECTIVE: MTX remains the cornerstone for therapy for RA, yet research shows that non-adherence is significant and correlates with response to therapy. This study aimed to halve self-reported non-adherence to MTX at the Kellgren Centre for Rheumatology. METHODS: An anonymous self-report adherence questionnaire was developed and data collected for 3 months prior to the introduction of interventions, and then regularly for the subsequent 2.5 years. A series of interventions were implemented, including motivational interviewing training, consistent information about MTX and development of a summary bookmark. Information on clinic times was collected for consultations with and without motivational interviewing. Surveys were conducted to ascertain consistency of messages about MTX. A biochemical assay was used to test MTX serum levels in patients at two time points: before and 2.8 years following introduction of the changes. Remission rates at 6 and 12 months post-MTX initiation were retrieved from patient notes and cost savings estimated by comparing actual numbers of new biologic starters compared with expected numbers based on the numbers of consultants employed at the two time points. RESULTS: Between June and August 2016, self-reported non-adherence to MTX was 24.7%. Following introduction of the interventions, self-reported non-adherence rates reduced to an average of 7.4% between April 2018 and August 2019. Clinic times were not significantly increased when motivational interviewing was employed. Consistency of messages by staff across three key areas (benefits of MTX, alcohol guidance and importance of adherence) improved from 64% in September 2016 to 94% in January 2018. Biochemical non-adherence reduced from 56% (September 2016) to 17% (June 2019), whilst remission rates 6 months post-initiation of MTX improved from 13% in 2014/15 to 37% in 2017/18, resulting is estimated cost savings of £30 000 per year. CONCLUSION: Non-adherence to MTX can be improved using simple measures including focussing on the adherence and the benefits of treatment, and providing consistent information across departments.

Molecular Mechanism for the Interactions of Hofmeister Cations with Macromolecules in Aqueous Solution.

Ion identity and concentration influence the solubility of macromolecules. To date, substantial effort has been focused on obtaining a molecular level understanding of specific effects for anions. By contrast, the role of cations has received significantly less attention and the underlying mechanisms by which cations interact with macromolecules remain more elusive. To address this issue, the solubility of poly(N-isopropylacrylamide), a thermoresponsive polymer with an amide moiety on its side chain, was studied in aqueous solutions with a series of nine different cation chloride salts as a function of salt concentration. Phase transition temperature measurements were correlated to molecular dynamics simulations. The results showed that although all cations were on average depleted from the macromolecule/water interface, more strongly hydrated cations were able to locally accumulate around the amide oxygen. These weakly favorable interactions helped to partially offset the salting-out effect. Moreover, the cations approached the interface together with chloride counterions in solvent-shared ion pairs. Because ion pairing was concentration-dependent, the mitigation of the dominant salting-out effect became greater as the salt concentration was increased. Weakly hydrated cations showed less propensity for ion pairing and weaker affinity for the amide oxygen. As such, there was substantially less mitigation of the net salting-out effect for these ions, even at high salt concentrations.

Molecular Scale Solvation in Complex Solutions.

Complex solution environments are ubiquitous in nature. Most life science systems contain hydrated macromolecules whose solubility, function and stability are modulated by several small organic molecules or salts (cosolutes) present simultaneously. This Perspective discusses solvation of mixed cosolutes in water. Recent computer simulations and experiments have shown that nonadditive cosolute effects on the water solubility of thermoresponsive polymers and on protein stability have a common physical origin, rooted in solvent-excluded volume effects determined by mutually enhanced cosolute hydration in bulk. We discuss mixtures of weakly and strongly hydrated salts in the anionic Hofmeister series and mixtures of urea and trimethylamine N-oxide. Nonadditive phenomena in these mixtures lead to intriguing effects including consecutive polymer collapse and swelling transitions and counteraction of denaturant-induced protein unfolding. The combination of today's advanced simulation methods and spectroscopy techniques should be used to improve further the understanding of these complex aqueous solubility problems.

Type I interferon in patients with systemic autoimmune rheumatic disease is associated with haematological abnormalities and specific autoantibody profiles.

OBJECTIVES: To investigate the relationships between interferon alpha (IFNα) and the clinical and serological phenotype of patients with systemic autoimmune rheumatic disease (SARDs) in order to determine whether a distinct subpopulation of patients can be identified. METHODS: We recruited patients with at least 1 SARD clinical feature and at least 1 SARD-related autoantibody from two NHS Trusts in Greater Manchester. A 6-gene interferon-stimulated gene (ISG) score was calculated in all patients, and in a subgroup, a 30-gene ISG score was produced using NanoString. A digital Single Molecule Array (Simoa) was used to measure plasma IFNα protein. In an exploratory analysis, whole blood RNA sequencing was conducted in 12 patients followed by RT-qPCR confirmation of expression of 6 nucleic acid receptors (NARs) in the whole cohort. RESULTS: Sixty three of 164 (38%) patients had a positive ISG score. The 3 measures of IFNα all correlated strongly with each other (p < 0.0001). There were no differences in mucocutaneous or internal organ involvement between the ISG subgroups. The ISG-positive group had increased frequency of specific autoantibodies and haematological abnormalities which remained significant after adjusting for the SARD subtype. Expression of DDX58, MB21D1 and TLR7 was correlated with the ISG score whilst TLR3, TLR9 and MB21D1 were associated with neutrophil count. CONCLUSION: In SARD patients, IFNα-positivity was associated with specific autoantibodies and haematological parameters but not with other clinical features. The variable NAR expression suggests that different pathways may drive IFNα production in individual patients. The identification of an IFNα-positive subgroup within a mixed SARD cohort supports a pathology-based approach to treatment.

Nonadditive Ion Effects Drive Both Collapse and Swelling of Thermoresponsive Polymers in Water.

When a mixture of two salts in an aqueous solution contains a weakly and a strongly hydrated anion, their combined effect is nonadditive. Herein, we report such nonadditive effects on the lower critical solution temperature (LCST) of poly( N-isopropylacrylamide) (PNiPAM) for a fixed concentration of Na2SO4 and an increasing concentration of NaI. Using molecular dynamics simulations and vibrational sum frequency spectroscopy, we demonstrate that at low concentrations of the weakly hydrated anion (I-), the cations (Na+) preferentially partition to the counterion cloud around the strongly hydrated anion (SO42-), leaving I- more hydrated. However, upon further increase in the NaI concentration, this weakly hydrated anion is forced out of solution to the polymer/water interface by sulfate. Thus, the LCST behavior of PNiPAM involves competing roles for ion hydration and polymer-iodide interactions. This concept can be generally applied to mixtures containing both a strongly and a weakly hydrated anion from the Hofmeister series.

Does an electronic continuum correction improve effective short-range ion-ion interactions in aqueous solution?

Non-polarizable force fields for hydrated ions not always accurately describe short-range ion-ion interactions, frequently leading to artificial ion clustering in bulk aqueous solutions. This can be avoided by adjusting the nonbonded anion-cation or cation-water Lennard-Jones parameters. This approach has been successfully applied to different systems, but the parameterization is demanding owing to the necessity of separate investigations of each ion pair. Alternatively, polarization effects may effectively be accounted for using the electronic continuum correction (ECC) of Leontyev et al. [J. Chem. Phys. 119, 8024 (2003)], which involves scaling the ionic charges with the inverse square-root of the water high-frequency dielectric permittivity. ECC has proven to perform well for monovalent salts as well as for divalent salts in water. Its performance, however, for multivalent salts with higher valency remains unexplored. The present work illustrates the applicability of the ECC model to trivalent K3PO4 and divalent K2HPO4 in water. We demonstrate that the ECC models, without additional tuning of force field parameters, provide an accurate description of water-mediated interactions between salt ions. This results in predictions of the osmotic coefficients of aqueous K3PO4 and K2HPO4 solutions in good agreement with experimental data. Analysis of ion pairing thermodynamics in terms of contact ion pair (CIP), solvent-separated ion pair, and double solvent-separated ion pair contributions shows that potassium-phosphate CIP formation is stronger with trivalent than with divalent phosphate ions.

Sleep in adolescents and young adults.

Sleep has an important role in maintaining health and wellbeing; this relationship is becoming increasingly recognised for adolescents and young adults. Many physicians will encounter young people who present with complaints or conditions that have some relation to poor sleep. This review article looks at why sleep matters within this population group, how it can impact on longer term health consequences and discusses some tools to help enable the clinician to evaluate and address sleep within clinical practice.