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ObjectiveTo study differences in pain reports between patients with ankylosing spondylitis (AS) and nonradiographic axial spondyloarthritis (nr-axSpA), and to assess how pain sensitivity measures associate with disease and health outcomes.MethodsConsecutive patients with axial SpA (axSpA) were enrolled in the population-based SPARTAKUS cohort (2015–2017) and classified as AS (n = 120) or nr-axSpA (n = 55). Pain was assessed with questionnaires (intensity/duration/distribution) and computerized cuff pressure algometry to measure pain sensitivity (pain threshold/pain tolerance/temporal summation of pain). Linear regression models were used to compare pain measures between patients with AS and nr-axSpA, and to assess associations between pain sensitivity measures and disease and health outcomes.ResultsOf 175 patients with axSpA, 43% reported chronic widespread pain, with no significant differences in any questionnaire-derived or algometry-assessed pain measures between patients with AS and nr-axSpA. Lower pain tolerance was associated with longer symptom duration, worse Ankylosing Spondylitis Disease Activity Score using C-reactive protein (ASDAS-CRP), Bath Ankylosing Spondylitis Functional Index, and Bath Ankylosing Spondylitis Metrology Index (BASMI), more pain regions, unacceptable pain, worse Maastricht AS Enthesitis Score (MASES), fatigue, anxiety, and health-related quality of life. Further, lower pain threshold was associated with worse ASDAS-CRP and MASES, whereas higher temporal summation was associated with longer symptom duration, unacceptable pain, and worse BASMI.ConclusionChronic pain is common in axSpA, with no observed differences in any pain measures between patients with AS and nr-axSpA. Further, higher pain sensitivity is associated with having worse disease and health outcomes. The results indicate that patients with AS and nr-axSpA, in line with most clinical characteristics, have a similar pain burden, and they highlight large unmet needs regarding individualized pain management, regardless of axSpA subgroup.

Ductile shear zones with dextral transpressive deformation separate the Ljusdal lithotectonic unit from the neighbouring units (Bothnia–Skellefteå and Bergslagen) in the 2.0–1.8 Ga Svecokarelian orogen. Sedimentation steered by regional crustal extension at c.1.86–1.83 Ga was sandwiched between two separate phases of ductile strain with crustal shortening and predominantly high-grade metamorphism with plutonic activity. Metamorphism occurred under low-pressure, medium- to high-temperature conditions that locally reached granulite facies. The earlier shortening event resulted in the accretion of outboard sedimentary and c.1.89 Ga volcanic rocks (formed in back- or inter-arc basin and volcanic arc settings, respectively) to a continental margin. Fabric development (D1), the earlier phase of low-pressure and variable temperature metamorphism (M1) and the intrusion of a predominantly granitic to granodioritic batholith with rather high εNdvalues (the Ljusdal batholith) occurred along this active margin at 1.87–1.84 Ga. Thrusting with westerly vergence, regional folding and ductile shearing (D2–3), the later phase of low-pressure and variable temperature metamorphism (M2), and the subsequent minor shear-related intrusion of granite, again with relatively high εNdvalues, prevailed at 1.83–1.80 Ga. Mineral deposits include epithermal Au–Cu deposits hosted by supracrustal rocks, V–Fe–Ti mineralization in subordinate gabbro and norite bodies inside the Ljusdal batholith, and graphite in metasedimentary rocks.

Two lithotectonic units (the Norrbotten and O¨verkalix units) occur inside the Paleoproterozoic (2.0–1.8 Ga) Svecokarelian orogen in northernmost Sweden. Archean (2.8–2.6 Ga and possibly older) basement, affected by a relict Neoarchean tectonometamorphic event, and early Paleoproterozoic (2.5–2.0 Ga) cover rocks constitute the pre-orogenic components in the orogen that are unique in Sweden. Siliciclastic sedimentary rocks, predominantly felsic volcanic rocks, and both spatially and temporally linked intrusive rock suites, deposited and emplaced at 1.9–1.8 Ga, form the syn-orogenic component. These magmatic suites evolved from magnesian and calc-alkaline to alkali–calcic compositions to ferroan and alkali–calcic varieties in a subduction-related tectonic setting. Apatite–Fe oxide, including the world's two largest underground Fe ore mines (Kiruna and Malmberget), skarn-related Fe oxide, base metal sulphide, and epigenetic Cu–Au and Au deposits occur in the Norrbotten lithotectonic unit. Low- to medium-pressure and variable temperature metamorphic conditions and polyphase Svecokarelian ductile deformation prevailed. The general northwesterly or north-northeasterly structural grain is controlled by ductile shear zones. The Paleotectonic evolution after the Neoarchean involved three stages: (1) intracratonic rifting prior to 2.0 Ga; (2) tectonic juxtaposition of the lithotectonic units during crustal shortening prior to 1.89 Ga; and (3) accretionary tectonic evolution along an active continental margin at 1.9–1.8 Ga.

The Bothnia–Skellefteå lithotectonic unit is dominated by turbiditic wacke and argillite (Bothnian basin), deposited at 1.96 (or older)–1.86 Ga, metamorphosed generally under high-grade conditions and intruded by successive plutonic suites at 1.95–1.93, 1.90–1.88, 1.87–1.85 and 1.81–1.76 Ga. In the northern part, low-grade and low-strain, 1.90–1.86 Ga predominantly magmatic rocks (the Skellefte–Arvidsjaur magmatic province) are enclosed by the basinal components. Subduction-related processes in intra-arc basin and magmatic arc settings, respectively, are inferred. Changes in the metamorphic grade and the relative timing of deformation and structural style across the magmatic province are linked to major shear zones trending roughly north–south and, close to the southern margin, WNW–ESE. Zones trending WNW–ESE and ENE–WSW dominate southwards. Slip along the north–south zones in an extensional setting initiated synchronously with magmatic activity at 1.90–1.88 Ga. Tectonic inversion steered by accretion to a craton to the east, involving crustal shortening, ductile strain and crustal melting, occurred at 1.88–1.85 Ga. Deformation along shear zones under lower-grade conditions continued at c.1.8 Ga. Felsic volcanic rocks (1.90–1.88 Ga) host exhalative and replacement-type volcanogenic massive sulphide deposits (the metallogenic Skellefte district). Other deposits include orogenic Au, particularly along the ‘gold line’ SW of this district, porphyry Cu–Au–Mo, and magmatic Ni–Cu along the ‘nickel line’ SE of the ‘gold line’.

Six separate lithotectonic units, referred to from north to south as the O¨verkalix, Norrbotten, Bothnia–Skellefteå, Ljusdal, Bergslagen and Småland units, are identified inside the western part of the 2.0–1.8 Ga Svecokarelian orogen, Fennoscandian Shield, Sweden. Apart from the boundary between the Norrbotten and Bothnia–Skellefteå lithotectonic units in northern Sweden, which is defined on the basis of a change in crustal basement from Neoarchean (and possibly older) in the NE (Norrbotten) to juvenile Paleoproterozoic crust further south (Bothnia–Skellefteå), all the boundaries are defined by shear zones or combinations of zones that, in places, form broader shear belts up to several tens of kilometres thick. The identification of lithotectonic units provides a necessary foundation for a more detailed synthesis of the tectonic evolution of the 2.0–1.8 Ga orogeny in northern Europe, emphasizing in particular the allochthoneity between most of these units inside this part of the orogen.

Objectives: To evaluate how radiographic damage, overall and measured as joint space narrowing score (JSNS) and erosion score (ES), as well as other clinical and laboratory measures, relate to disability and pain in early rheumatoid arthritis (RA). Methods: An inception cohort of 233 patients with early RA, recruited in 1995–2005, was followed for 5 years. Disability was assessed with the Health Assessment Questionnaire (HAQ), and pain with a visual analogue scale (VAS; 0–100 mm). Radiographs of hands and feet were evaluated using the Sharp-van der Heijde score (SHS), including JSNS and ES. The relation for radiographic scores and other clinical parameters with pain and HAQ were evaluated cross-sectionally by multivariate linear regression analysis and over time using generalized estimating equations. Results: ES was significantly associated with HAQ cross-sectionally at inclusion, after 2 and after 5 years, and over time. Associations for HAQ with SHS and JSNS were weaker and less consistent compared with those for ES. There was no association between radiographic scores and pain at any visit. Both HAQ and pain were associated with parameters of disease activity. The strongest cross-sectional associations were found for the number of tender joints (adjusted p<0.001 at all visits). Conclusion: Joint damage was associated with disability already in early RA. Erosions of hands and feet appear to have a greater influence on disability compared with joint space narrowing early in the disease. Pain was associated with other factors than joint destruction in early RA, in particular joint tenderness—suggesting an impact of pain sensitization.

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The aim of this study was to study the relationship between insulin-like growth factor-1 (IGF-1), serum phospholipid fatty acids, and growth in healthy full-term newborns during infancy. Prospective observational study of a population-based Swedish cohort comprising 126 healthy, term infants investigating cord blood and serum at 2 days and 4 months of age for IGF-1 and phospholipid fatty acid profile and breast milk for fatty acids at 2 days and 4 months, compared with anthropometric measurements (standard deviation scores). At all time-points arachidonic acid (AA) was negatively associated with IGF-1. IGF-1 had positive associations with linoleic acid (LA) at 2 days and 4 months and mead acid (MA) showed positive associations in cord blood. Multiple regression analyses adjusted for maternal factors (body mass index, weight gain, smoking, education), sex, birth weight and feeding modality confirmed a negative association for the ratio AA/LA to IGF-1. MA in cord blood correlated to birth size. Changes in the ratios of n-6/n-3 and AA/docosahexaenoic acid from day 2 to 4 months together with infants' weight and feeding modality determined 55% of the variability of delta-IGF-1. Breast-fed infants at 4 months had lower IGF-1 correlating with lower LA and higher AA concentrations, which in girls correlated with lower weight gain from birth to 4 months of age. Our data showed interaction of n-6 fatty acids with IGF-1 during the first 4 months of life, and an association between MA and birth size when adjusted for confounding factors. Further follow-up may indicate whether these correlations are associated with later body composition.

Depression is frequent in ankylosing spondylitis (AS) patients. However, epidemiological data about the potential increase in risk are lacking. This study compares the rate of doctor-diagnosed depression in a well defined cohort of AS patients to the general population seeking care. The Skåne Healthcare Register comprises healthcare data of each resident in Region Skåne, Sweden (population 1.2 million), including ICD-10 diagnoses. Using physician coded consultation data from years 1999 to 2011, we calculated depression consultation rates for all AS patients. We obtained standardized depression-rate ratios by dividing the observed depression rate in AS patients by the expected rate based on the corresponding age- and sex-specific rates of depression in the general population seeking care. A ratio >1 equals a higher rate of depression among AS patients. The AS cohort consisted of 1738 subjects (65% men) with a mean age of 54 years. The reference population consisted of 967,012 subjects. During the 13-year observation period 10% (n = 172) of the AS cohort had a doctor-diagnosed depression compared to 6% (n = 105) to be expected. The standardized estimate of depression-rate ratio was 1.81 (95% confidence interval 1.44 to 2.24) in women men and 1.49 (1.20 to 1.89) in men. The rate of doctor-diagnosed depression is increased about 80% in female and 50% in male AS patients. Future challenges are to timely identify and treat the AS patients who suffer from depression.

It is not known whether snuff (moist smokeless tobacco) affects disease activity in rheumatoid arthritis (RA).

Objective.To study the prevalence of chronic widespread pain (ChWP), chronic regional pain (ChRP), and fibromyalgia in patients with early rheumatoid arthritis (RA) followed for 5 years after inclusion, and to study the effect of pain on measures of disease activity and function.Methods.A questionnaire was sent to 1910 patients participating in the Better Anti-Rheumatic Pharmacotherapy study. The responders (73%) were divided into 3 groups according to the reported pain duration and distribution — patients having no chronic pain (NChP), ChWP, and ChRP. Outcome measures were the 28-joint Disease Activity Score (DAS28), the Health Assessment Questionnaire (HAQ), and C-reactive protein (CRP).Results.Thirty-four percent of respondents reported ChWP, 46% ChRP, and 20% NChP. Patients reporting ChWP were more often women and had more pain and tender joints at inclusion. From 6 months to 5 years of followup, mean DAS28, visual analog scale (VAS) pain, VAS global health, and HAQ were significantly higher in the ChWP group than in the other groups. However, all groups showed a similar pattern in swollen joint count, erythrocyte sedimentation rate (ESR), and CRP. From 12 months the ChWP group was treated with prednisolone to a greater extent than the ChRP group, and it had a rate of treatment with disease-modifying antirheumatic drugs similar to that of the ChRP group.Conclusion.ChWP is a common feature in RA, more associated with high values for variables related to pain such as the DAS28 and HAQ than to indicators of ongoing inflammation such as swollen joint count, ESR, and CRP. Patients with ChWP should be identified so that adequate treatment also of the noninflammatory pain may be instituted.

OBJECTIVE: To study the effect of disease duration and smoking on outcome in early rheumatoid arthritis (RA). METHODS: Between 1996 and 2004, 1587 patients were included in the BARFOT early RA (disease duration ≤ 1 year) study in Sweden. European League Against Rheumatism (EULAR) response, Health Assessment Questionnaire (HAQ), rheumatoid factor (RF), and antibodies to cyclic citrullinated peptide (anti-CCP) were recorded at study start and at 3, 6, and 12 months. RESULTS: In total, 180 RA patients (11%) had disease duration ≤ 12 weeks. These patients achieved good EULAR response significantly more often at 3 and 12 months than patients with a longer disease duration despite having more aggressive disease [EULAR good response was achieved by 35% and 35% at 3 and 12 months, respectively, among the patients with disease duration ≤ 12 weeks, by 35% and 41% of patients with disease duration of 13–24 weeks, and by 28% and 33% of patients with disease duration of 25–52 weeks (p = 0.02 for 3 months; p = 0.02 for 12 months)]. There was a significant correlation between improvement in Disease Activity Score-28 (DAS28), its individual variables, and Health Assessment Questionnaire (HAQ) and disease duration up to 12 months after study start. For smokers, no such trend was seen. CONCLUSION: Up to 12 months after inclusion in the study, there was a significant correlation between improvement in DAS28, its individual components, and HAQ and disease duration, with patients who had a shorter disease duration improving most. Smokers had poorer EULAR response and showed no improvement with regard to disease duration.

Objectives: Pain is a major symptom in patients with rheumatoid arthritis (RA). In early RA, pain is usually due to synovitis, but can also persist despite effective anti-inflammatory treatment. The objective of this study was to investigate the pain course over time and predictors of unacceptable pain and unacceptable pain with low inflammation, in patients with early RA. Methods: An inception cohort of 232 patients with early RA, recruited in 1995–2005, was followed in a structured programme for 5 years. Pain was assessed using a visual analogue scale (VAS; 0–100). Unacceptable pain was defined as VAS pain > 40 based on the patient acceptable symptom state (PASS) and low inflammation as CRP < 10 mg/l. Baseline predictors of unacceptable pain were evaluated using logistic regression analysis. Results: Pain improved significantly during the first 6 months, but then remained basically unchanged. Thirty-four per cent of the patients had unacceptable pain 5 years after inclusion. Baseline predictors of unacceptable pain after 5 years were lower swollen joint counts [odds ratio (OR) 0.71 per standard deviation (95% confidence interval (CI) 0.51–0.99)] and higher VAS for pain and global assessment of disease activity. Unacceptable pain with low inflammation after 5 years was negatively associated with anti-CCP antibodies [OR 0.50 (95% CI 0.22–0.98)]. Conclusion: Over one third of the patients had unacceptable pain 5 years after inclusion. Lower swollen joint count was associated with unacceptable pain at 5 years. The results may be explained by the positive effects of treatment on pain related to inflammation. Non-inflammatory long-lasting pain appears to be a greater problem in anti-CCP-negative patients.

Musculoskeletal disorders are the most common cause of long-term sick leave in several western countries and individuals with chronic musculoskeletal pain score very low on health status measurements. Musculoskeletal health is multidimensional and is best understood from a biopsychosocial perspective. Body structure and function interacts with personal and environmental factors, affecting the ability to perform activities and participate in society. Interventions aimed at the whole population must attend to the underlying causes of musculoskeletal disorders and promote a healthy lifestyle. Safe environments and activities could reduce the risk of traumatic events and also make participation possible for those with a disability. Public beliefs about musculoskeletal symptoms and consequences need to be changed in order to minimise fear and avoidance, which, together with other psychosocial factors, could lead to chronicity. Public awareness and identification of those at risk for the development of musculoskeletal problems could lead to early and properly timed management.

Chronic musculoskeletal pain is a major public health problem affecting about one third of the adult population. Pain is often present without any specific findings in the musculoskeletal system and a strictly biomedical approach could be inadequate. A biopsychosocial model could give a better understanding of symptoms and new targets for management. Identification of risk factors for chronicity is important for prevention and early intervention. The cornerstones in management of chronic non-specific, and often widespread, musculoskeletal pain are non-pharmacological. Physical exercise and cognitive behavioral therapy, ideally in combination, are first line treatments in e.g. chronic low back pain and fibromyalgia. Analgesics are useful when there is a specific nociceptive component, but are often of limited usefulness in non-specific or chronic widespread pain (including fibromyalgia). Antidepressants and anticonvulsants could be of value in some patients but there is a need for more knowledge in order to give general recommendations.

This paper presents U-Pb ages for an extended period of geological evolution between about 1860 and 1740 Ma in the northern part of the Fennoscandian Shield. It involved magmatism, ductile deformation and metamorphism along the border between Sweden and Finland. The study area separates into a western and an eastern domain roughly along a north-south trending structural boundary defined by the western margin of the Pajala shear zone. Approximately 1860-1850 Ma zircon ages from two granitoid rocks record contrasting post-emplacement deformation histories on either side of this boundary. While metamorphic monazite records c. 1850 Ma events in rocks of the western domain, metamorphic monazite and titanite as well as zircon overgrowths in the eastern domain verify deformation and high-grade metamorphism in the 1820-1780 Ma interval. This post-1820 Ma phase is most probably related to shear zones and to nearby intrusions. A titanite age at c. 1740 Ma in the eastern domain is suggested to exemplify a tectonic phase, which elsewhere in northern Fennoscandia is marked by fracturing, generation of pegmatites, and hydrothermal activity.

OBJECTIVE: To describe the change of pain reports over time in 3 cohorts derived from the general population: (1) no chronic pain (NCP; n = 1156); (2) chronic regional pain (CRP; n = 502); and (3) chronic widespread pain (CWP; n = 242). To identify risk factors that predict the development or persistence of chronic widespread pain. METHODS: A 3-year followup from 1995 to 1998 with postal questionnaire to 2425 subjects of both sexes aged 20-74 years on the west coast of Sweden. RESULTS: At followup, a larger proportion of subjects with initial CRP compared to initial NCP reported CWP (16.4 and 2.2%, respectively; p < 0.001). The majority of subjects (56.9%) who primarily reported CWP remained in that group at followup, but 26.8% had changed status to CRP and 16.3% to NCP. The number of painful regions (7-12 vs 0 regions) reported at baseline was the strongest predictor for the development of CWP with an odds ratio (OR) of 12.13 (95% CI 4.47-32.88). The development of CWP was also predicted by higher age (OR = 3.13, 95% CI 1.47-6.69, age-group 59-74 years vs age-group 20-34 years), and a family history of chronic pain (OR = 1.87, 95% CI 1.14-3.07). A habit of drinking alcohol weekly (OR = 0.42, 95% CI 0.21-0.85) compared to the habit of never or seldom drinking alcohol was protective, as well as having personal social support (OR = 0.49, 95% CI 0.28-0.85). The persistence of CWP was predicted by the number of painful regions (13-18 vs 1-6 regions) at baseline (OR = 7.56, 95% CI 2.17-26.30), and being an immigrant (OR = 3.22, 95% CI 1.33-7.77). CONCLUSION: Although the overall prevalence of CWP was stable over a 3-year period there was a considerable variation on an individual basis. This variability in expressing CWP was moderately predicted by a combination of risk factors, the most important being the number of painful regions at baseline. Future research will need to show how useful the identified factors are in clinical practice and whether intervention aimed at changing these factors will improve pain outcome.

The Seve-Ko¨li boundary in the central Scandinavian Caledonides represents the transition from Baltica continental margin-related rocks (Seve) to outboard, westerly derived terranes (Ko¨li). In this study we present and discuss structural and kinematic data recording the syn- and post-accretionary evolution of this boundary in west central Sweden.

The author considers a schlicht pseudo-conformal mapping of a domainBin the (z1, z2)-space onto the Reinhardt circular domainCin the (ξ1, ξ2)-space by a pair of functions (see (1)§ 1). The domainBis assumed to include the bicylinder ((2)§2) and to omit four planes zk=ak, zk=bk, k=1, 2. Upper bounds for a sequence of the coefficientsμv(k)of the developments (1) are given, see p. 304. The upper bounds depend only on ak, bk, k=1, 2, and on the radii rkof the bicylinder ((2)§2). The bounds are obtained by using the method of the kernel function. The result can be considered as an analogue to the inequalities of Grunsky in the theory of functions of one complex variable.