A systematic review and meta-analysis of the prevalence of chronic widespread pain in the general population.

Chronic widespread pain (CWP) is common and associated with poor general health. There has been no attempt to derive a robust prevalence estimate of CWP or assess how this is influenced by sociodemographic factors. This study therefore aimed to determine, through a systematic review and meta-analysis, the prevalence of CWP in the adult general population and explore variation in prevalence by age, sex, geographical location, and criteria used to define CWP. MEDLINE, Embase, CINAHL, and AMED were searched using a search strategy combining key words and related database-specific subject terms to identify relevant cohort or cross-sectional studies published since 1990. Included articles were assessed for risk of bias. Prevalence figures for CWP (American College of Rheumatology criteria) were stratified according to geographical location, age, and sex. Potential sources of variation were investigated using subgroup analyses and meta-regression. Twenty-five articles met the eligibility criteria. Estimates for CWP prevalence ranged from 0% to 24%, with most estimates between 10% and 15%. The random-effects pooled prevalence was 10.6% (95% confidence intervals: 8.6-12.9). When only studies at low risk of bias were considered pooled, prevalence increased to 11.8% (95% confidence intervals: 10.3-13.3), with reduced but still high heterogeneity. Prevalence was higher in women and in those aged more than 40 years. There was some limited evidence of geographic variation and cultural differences. One in 10 adults in the general population report chronic widespread pain with possible sociocultural variation. The possibility of cultural differences in pain reporting should be considered in future research and the clinical assessment of painful conditions

Identifying patients with chronic widespread pain in primary care.

Chronic widespread pain (CWP) is common in the general population. It is unclear how people reporting this problem present in primary care; they may regularly consult for regional pains without being recognized as having a generalized condition. Our objectives were to determine the prevalence of people consulting in primary care for musculoskeletal conditions in different body regions on different occasions (recurrent regional pain consultation), the proportion with diagnosed generalized pain and survey-reported widespread pain, and if they have features characteristic of CWP. Phase 1 used electronic records from 12 general practices in North Staffordshire (Consultations in Primary Care Archive) from 2005 to 2009. Phase 2 used linked self-reported health and primary healthcare data from 8,286 people aged 50 plus in eight general practices (North Staffordshire Osteoarthritis Project) between 2002 and 2005. In Phase 1, 11% of registered patients fulfilled criteria for recurrent regional pain consultation. Three-quarters had no recorded CWP-related generalized pain condition (e.g. fibromyalgia). In Phase 2, 53% of recurrent regional pain consulters had survey-reported widespread pain and 88% had consulted for somatic symptoms. Self-reported general health was worse in recurrent regional pain consulters than in single-region consulters, and poorest in those who also reported persistent widespread pain. Recurrent regional pain consulters are a heterogeneous group of frequent consulters sharing features with CWP (e.g. somatic symptoms) but including those less severely affected. They lie on the spectrum of polysymptomatic distress characteristic of CWP and represent a group whose needs may be better met by earlier diagnosis of multi-site pain.This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0 (CC BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

Analytical approximations to numerical solutions of theoretical emission measure distributions

Emission line fluxes from cool stars are widely used to establish an apparent emission measure distribution, Emd-app(Te), between temperatures characteristic of the low transition region and the low corona. The true emission measure distribution, Emd-t(Te), is determined by the energy balance and geometry adopted and, with a numerical model, can be used to predict Emd-app(Te), to guide further modelling. The scaling laws that exist between coronal parameters arise from the dimensions of the terms in the energy balance equation. Here, analytical approximations to numerical solutions for Emd-t(Te) are presented, which show how the constants in the coronal scaling laws are determined. The apparent emission measure distributions show a minimum value at some temperature (T0) and a maximum at the mean coronal temperature Tc (although in some stars, emission from active regions can contribute). It is shown that, for the energy balance and geometry adopted, the analytical values of the emission measure and electron pressure at T0 and Tc, depend on only three parameters: the stellar surface gravity and the values of T0 and Tc. The results are tested against full numerical solutions for Epsilon Eri (K2 V) and are applied to Procyon (alpha CMi; F5 IV/V). The analytical approximations can be used to restrict the required range of full numerical solutions, to check the assumed geometry and to show where the adopted energy balance may not be appropriate.Comment: 9 pages, accepted by MNRA

Enhancement of the helium resonance lines in the solar atmosphere by suprathermal electron excitation I: non-thermal transport of helium ions

Models of the solar transition region made from lines other than those of helium cannot account for the strength of the helium lines. However, the collisional excitation rates of the helium resonance lines are unusually sensitive to the energy of the exciting electrons. Non-thermal motions in the transition region could drive slowly-ionizing helium ions rapidly through the steep temperature gradient, exposing them to excitation by electrons characteristic of higher temperatures than those describing their ionization state. We present the results of calculations which use a more physical representation of the lifetimes of the ground states of He I and He II than was adopted in earlier work on this process. New emission measure distributions are used to calculate the temperature variation with height. The results show that non-thermal motions can lead to enhancements of the He I and He II resonance line intensities by factors that are comparable with those required. Excitation by non-Maxwellian electron distributions would reduce the effects of non-thermal transport. The effects of non-thermal motions are more consistent with the observed spatial distribution of helium emission than are those of excitation by non-Maxwellian electron distributions alone. In particular, they account better for the observed line intensity ratio I(537.0 A)/I(584.3 A), and its variation with location.Comment: 12 pages, 7 figures, accepted to appear in MNRAS, LaTeX uses mn.st

The emission line near 1319 A in solar and stellar spectra

An emission line near 1319 A is one of the strongest unidentified lines in the ultraviolet spectra of cool dwarf stars. In most line lists it is identified as a transition in N I, although its intensity would then be anomalous and the observed wavelength does not fit precisely that expected for N I. The line is also observed in cool giant stars. The measured wavelength of the line in stellar spectra is 1318.94 (+,- 0.01) A. Observations of giant stars provide further evidence that this line is not due to N I. It is proposed that this line is a decay from a previously unknown level in S I, which lies above the first ionization limit. This is identified with the 3d singlet D (odd parity) term. The previous tentative assignment of this term to the S I line at 1309.3 A then needs to be revised. The 1309.3 A line has been identified here for the first time in an astrophysical source. The singlet D (odd parity) level could, in principle, be populated by collisions from nearby autoionizing levels that have large number-densities, through population by di-electronic capture. Spin-orbit interaction with the autoionizing triplet D (odd parity) term might also lead to di-electronic capture into the singlet D (odd parity) level. A line at 1309.87 A observed in cool giant stars is identified as a transition in P II, pumped by the O I resonance lines.Comment: 9 pages, 3 figures, to be published in Monthly Notices of the Royal Astronomical Societ

Distinctiveness of long-term pain that does not interfere with life: an observational cohort study.

BACKGROUND: Reporting of pain that does not interfere with life is common in the older population but little is known about people with such long-term non-interfering pain. OBJECTIVES: To assess whether non-interfering pain can be a long-term state, and to compare this group with those who continuously report no pain, and with those with chronic pain that interferes with life. METHODS: This was a prospective general population cohort study set within the North Staffordshire Osteoarthritis Project (NorStOP). People aged 50 plus were sent baseline, 3-year and 6-year questionnaires. Those who reported the same pain status (no pain, non-interfering pain, interfering pain) at each time point were compared on pain intensity, widespread pain and medication, and on sociodemographic and co-morbid characteristics at 6 years. RESULTS: Forty percent of responders reported the same pain status at each time point; 12% reported long-term non-interfering pain. Fifty-nine percent of those with non-interfering pain reported at least one site of high pain intensity, 33% reported widespread pain, and 90% had used pain medication in the past 4 weeks. This group was similar to the no-pain group but distinct on sociodemographic and co-morbid measures from those with pain that interfered. CONCLUSIONS: Long-term non-interfering pain is common, but despite often suffering from high pain intensity and widespread pain, those within this group seem to be able to control their pain without allowing it to affect their everyday lives. Future work is needed to assess how people with long-term pain ensure it does not cause interference with life

Modelling the chromosphere and transition region of Epsilon Eri (K2 V)

Measurements of ultraviolet line fluxes from Space Telescope Imaging Spectrograph and Far-Ultraviolet Spectroscopic Explorer spectra of the K2-dwarf Epsilon Eri are reported. These are used to develop new emission measure distributions and semi-empirical atmospheric models for the chromosphere and lower transition region of the star. These models are the most detailed constructed to date for a main-sequence star other than the Sun. New ionisation balance calculations, which account for the effect of finite density on dielectronic recombination rates, are presented for carbon, nitrogen, oxygen and silicon. The results of these calculations are significantly different from the standard Arnaud & Rothenflug ion balance, particularly for alkali-like ions. The new atmospheric models are used to place constraints on possible First Ionisation Potential (FIP) related abundance variations in the lower atmosphere and to discuss limitations of single-component models for the interpretation of certain optically thick line fluxes.Comment: 22 pages, 9 figure

The value of prognostic ultrasound features of breast cancer in different molecular subtypes with a focus on triple negative disease

The ultrasound (US) features of breast cancer have recently been shown to have prognostic significance. We aim to assess these features according to molecular subtype. 1140 consecutive US visible invasive breast cancers had US size and mean stiffness by shearwave elastography (SWE) recorded prospectively. Skin thickening (> 2.5 mm) overlying the cancer on US and the presence of posterior echo enhancement were assessed retrospectively while blinded to outcomes. Cancers were classified as luminal, triple negative (TN) or HER2 + ve based on immunohistochemistry and florescent in-situ hybridization. The relationship between US parameters and breast cancer specific survival (BCSS) was ascertained using Kaplan–Meier survival curves and ROC analysis. At median follow-up 6.3 year, there were 117 breast cancer (10%) and 132 non-breast deaths (12%). US size was significantly associated with BCSS all groups (area under the curve (AUC) 0.74 in luminal cancers, 0.64 for TN and 0.65 for HER2 + ve cancers). US skin thickening was associated most strongly with poor prognosis in TN cancers (53% vs. 80% 6 year survival, p = 0.0004). Posterior echo enhancement was associated with a poor BCSS in TN cancers (63% vs. 82% 6 year survival, p = 0.02). Mean stiffness at SWE was prognostic in the luminal and HER2 positive groups (AUC 0.69 and 0.63, respectively). In the subgroup of patients with TN cancers receiving neo-adjuvant chemotherapy posterior enhancement and skin thickening were not associated with response. US skin thickening is a poor prognostic indicator is all 3 subtypes studied, while posterior enhancement was associated with poor outcome in TN cancer