Örjan Dahlström

The Ease of Language Understanding (ELU) model: theoretical, empirical, and clinical advances

Working memory is important for online language processing during conversation. We use it to maintain relevant information, to inhibit or ignore irrelevant information, and to attend to conversation selectively. Working memory helps us to keep track of and actively participate in conversation, including taking turns and following the gist. This paper examines the Ease of Language Understanding model (i.e., the ELU model, Rönnberg, 2003; Rönnberg et al., 2008) in light of new behavioral and neural findings concerning the role of working memory capacity (WMC) in uni-modal and bimodal language processing. The new ELU model is a meaning prediction system that depends on phonological and semantic interactions in rapid implicit and slower explicit processing mechanisms that both depend on WMC albeit in different ways. It is based on findings that address the relationship between WMC and (a) early attention processes in listening to speech, (b) signal processing in hearing aids and its effects on short-term memory, (c) inhibition of speech maskers and its effect on episodic long-term memory, (d) the effects of hearing impairment on episodic and semantic long-term memory, and finally, (e) listening effort. New predictions and clinical implications are outlined. Comparisons with other WMC and speech perception models are made.

Injury patterns in Swedish elite athletics: annual incidence, injury types and risk factors

Objective To estimate the incidence, type and severity of musculoskeletal injuries in youth and adult elite athletics athletes and to explore risk factors for sustaining injuries. Design Prospective cohort study conducted during a 52-week period. Setting Male and female youth and adult athletics athletes ranked in the top 10 in Sweden (n=292). Results 199 (68%) athletes reported an injury during the study season. Ninety-six per cent of the reported injuries were non-traumatic (associated with overuse). Most injuries (51%) were severe, causing a period of absence from normal training exceeding 3 weeks. Log-rank tests revealed risk differences with regard to athlete category (p=0.046), recent previous injury (>3 weeks time-loss; p=0.039) and training load rank index (TLRI; p=0.019). Cox proportional hazards regression analyses showed that athletes in the third (HR 1.79; 95% CI 1.54 to 2.78) and fourth TLRI quartiles (HR 1.79; 95% CI 1.16 to 2.74) had almost a twofold increased risk of injury compared with their peers in the first quartile and interaction effects between athlete category and previous injury; youth male athletes with a previous serious injury had more than a fourfold increased risk of injury (HR=4.39; 95% CI 2.20 to 8.77) compared with youth females with no previous injury. Conclusions The injury incidence among both youth and adult elite athletics athletes is high. A training load index combing hours and intensity and a history of severe injury the previous year were predictors for injury. Further studies on measures to quantify training content and protocols for safe return to athletics are warranted.

Factors related to fatigue in women and men with early rheumatoid arthritis: the Swedish TIRA study.

OBJECTIVE To study whether there are differences between women and men with regard to the reported level of fatigue, to explore the strength of the relations between fatigue and disease activity, pain, sleep disturbance, mental health, and activity limitation in early rheumatoid arthritis, and to explore the consistency of such findings. DESIGN Analyses and comparisons of cross-sectional data. SUBJECTS Two hundred and seventy-six patients, 191 women and 85 men, with early rheumatoid arthritis were included. METHODS Patients were examined with respect to 28-joint count disease activity score, and disability variables reflecting pain, sleep disturbance, fatigue, mental health, and activity limitation, at follow-ups at 1, 2 and 3 years after diagnosis. RESULTS Women reported somewhat more fatigue than men. Fatigue was closely and rather consistently related to disease activity, pain and activity limitation, and also to mental health and sleep disturbance. CONCLUSION Although this study does not permit conclusions to be drawn about causal directions, statistical relationships may be related to clinical conceptions about causation: when disease activity can be significantly reduced by pharmacological treatment this may have a positive effect on fatigue. Specific treatment with respect to the mentioned disability aspects that are related to fatigue is also a clinically reasonable strategy.

Application of the 2012 Systemic Lupus International Collaborating Clinics classification criteria to patients in a regional Swedish systemic lupus erythematosus register.

IntroductionIn 2012, the Systemic Lupus International Collaborating Clinics (SLICC) network presented a new set of criteria (SLICC-12) to classify systemic lupus erythematosus (SLE). The present study is the first to evaluate the performance of SLICC-12 in an adult European study population. Thus, SLICC-12 criteria were applied to confirmed SLE cases in our regional SLE register as well as to individuals with a fair suspicion of systemic autoimmune disease who were referred to rheumatology specialists at our unit.MethodsWe included 243 confirmed SLE patients who met the 1982 American College of Rheumatology (ACR-82) classification criteria and/or the Fries ‘diagnostic principle’ (presence of antinuclear antibodies on at least one occasion plus involvement of at least two defined organ systems) and 55 controls with possible systemic autoimmune disease, including the presence of any SLE-related autoantibody.ResultsSLICC-12 showed a diagnostic sensitivity of 94% (95% confidence interval (CI), 0.90 to 0.96) compared with 90% (95% CI, 0.85 to 0.93) for the updated set of ACR criteria from 1997 (ACR-97), whereas ACR-82 failed to identify every fifth true SLE case. However, the disease specificity of SLICC-12 reached only 74% (95% CI, 0.60 to 0.84) and did not change much when involvement of at least two different organs was required as an indicator of systemic disease. In addition, SLICC-12 misclassified more of the controls compared to ACR-82, ACR-97 and Fries.ConclusionsEstablishing a standard definition of SLE continues to challenge lupus researchers and clinicians. We confirm that SLICC-12 has advantages with regard to diagnostic sensitivity, whereas we found the diagnostic specificity to be surprisingly low. To accomplish increased sensitivity and specificity figures, a combination of criteria sets for clinical SLE studies should be considered.

Disease activity and disability in women and men with early rheumatoid arthritis (RA) : An 8-year followup of a Swedish early RA project

To compare women and men regarding the course of disease activity and disability over 8 years from diagnosis of recent‐onset rheumatoid arthritis (RA).

Physical fitness in northern European youth: Reference values from the Latvian Physical Health in Youth Study:

Aims: Physical fitness has the potential to be used as a key health determinant in youth. The aim of this study was to establish age- and sex-stratified reference values for health-related physical fitness in Latvian school-age children and to identify notable sex differences. Methods: Physical fitness was assessed using the EUROFIT test battery. Data were gathered from schoolchildren aged between 6 and 17 years (n = 10,464) by a medical team using standardised methods (EUROFIT battery). Fitness levels, stratified by chronological age and sex, were computed as mean ± SD. Each test was also analysed for differences between males and females in each age group. Results: Boys performed better than girls in muscular endurance and strength, cardiorespiratory endurance, and speed—agility fitness tests. Girls had better flexibility than boys (p < 0.001). There was also a more pronounced improvement in physical fitness scores with age in boys compared with girls. Conclusions: Physical fitness reference values were developed for Latvian children and adolescents. These reference values will permit comparisons between students during physical education lessons and provide a baseline against which progress in physical fitness among northern European youths can be compared.

Associations between antinuclear antibody staining patterns and clinical features of systemic lupus erythematosus: analysis of a regional Swedish register

Objective Antinuclear antibody (ANA) analysis by immunofluorescence (IF) microscopy remains a diagnostic hallmark of systemic lupus erythematosus (SLE). The clinical relevance of ANA fine-specificities in SLE has been addressed repeatedly, whereas studies on IF-ANA staining patterns in relation to disease manifestations are very scarce. This study was performed to elucidate whether different staining patterns associate with distinct SLE phenotypes. Design Observational cohort study. Setting One university hospital rheumatology unit in Sweden. Participants The study population consisted of 222 cases (89% women; 93% Caucasians), where of 178 met ≥4/11 of the 1982 American College of Rheumatology (ACR-82) criteria. The remaining 20% had an SLE diagnosis based on positive IF-ANA (HEp-2 cells) and ≥2 typical organ manifestations at the time of diagnosis (Fries’ criteria). Outcome measures The IF-ANA staining patterns homogenous (H-ANA), speckled (S-ANA), combined homogenous and speckled (HS-ANA), centromeric (C-ANA), nucleolar (N-ANA)±other patterns and other nuclear patterns (oANA) were related to disease manifestations and laboratory measures. Antigen-specificities were also considered regarding double-stranded DNA (Crithidia luciliae) and the following extractable nuclear antigens: Ro/SSA, La/SSB, Smith antigen (Sm), small nuclear RNP (snRNP), Scl-70 and Jo-1 (immunodiffusion and/or line-blot technique). Results 54% of the patients with SLE displayed H-ANA, 22% S-ANA, 11% HS-ANA, 9% N-ANA, 1% C-ANA, 2% oANA and 1% were never IF-ANA positive. Staining patterns among patients meeting Fries’ criteria alone did not differ from those fulfilling ACR-82. H-ANA was significantly associated with the 10th criterion according to ACR-82 (‘immunological disorder’). S-ANA was inversely associated with arthritis, ‘immunological disorder’ and signs of organ damage. Conclusions H-ANA is the dominant IF-ANA pattern among Swedish patients with SLE, and was found to associate with ‘immunological disorder’ according to ACR-82. The second most common pattern, S-ANA, associated negatively with arthritis and organ damage.

Preparticipation injury complaint is a risk factor for injury: a prospective study of the Moscow 2013 IAAF Championships

Objectives To determine the health status of athletes before the start of an international athletics championship and to determine whether preparticipation risk factors predicted in-championship injuries. Methods At the beginning of the 2013 International Association of Athletics Federations (IAAF) World Championships, all registered athletes (n=1784) were invited to complete a preparticipation health questionnaire (PHQ) on health status during the month preceding the championships. New injuries that occurred at the championships were prospectively recorded. Results The PHQ was completed by 698 (39%) athletes; 204 (29.2%) reported an injury complaint during the month before the championships. The most common mode of onset of preparticipation injury complaints was gradual (43.6%). Forty-nine athletes in the study reported at least one injury during the championships. Athletes who reported a preparticipation injury complaint were at twofold increased risk for an in-championship injury (OR=2.09; 95% CI 1.16 to 3.77); p=0.014). Those who reported a preparticipation gradual-onset injury complaint were at an almost fourfold increased risk for an in-championship time-loss injury (OR=3.92; 95% CI 1.69 to 9.08); p=0.001). Importantly, the preparticipation injury complaint severity score was associated with the risk of sustaining an in-championship injury (OR=1.14; 95% CI 1.06 to 1.22); p=0.001). Summary and conclusions About one-third of the athletes participating in the study reported an injury complaint during the month before the championships, which represented a risk factor for sustaining an injury during the championship. This study emphasises the importance of the PHQ as a screening tool to identify athletes at risk of injuries before international championships.

The psychological factor ‘self-blame’ predicts overuse injury among top-level Swedish track and field athletes: a 12-month cohort study

Background Athletes’ psychological characteristics are important for understanding sports injury mechanisms. We examined the relevance of psychological factors in an integrated model of overuse injury risk in athletics/track and field. Methods Swedish track and field athletes (n=278) entering a 12-month injury surveillance in March 2009 were also invited to complete a psychological survey. Simple Cox proportional hazards models were compiled for single explanatory variables. We also tested multiple models for 3 explanatory variable groupings: an epidemiological model without psychological variables, a psychological model excluding epidemiological variables and an integrated (combined) model. Results The integrated multiple model included the maladaptive coping behaviour self-blame (p=0.007; HR 1.32; 95% CI 1.08 to 1.61), and an interaction between athlete category and injury history (p<0.001). Youth female (p=0.034; HR 0.51; 95% CI 0.27 to 0.95) and youth male (p=0.047; HR 0.49; 95% CI 0.24 to 0.99) athletes with no severe injury the previous year were at half the risk of sustaining a new injury compared with the reference group. A training load index entered the epidemiological multiple model, but not the integrated model. Conclusions The coping behaviour self-blame replaced training load in an integrated explanatory model of overuse injury risk in athletes. What seemed to be more strongly related to the likelihood of overuse injury was not the athletics load per se, but, rather, the load applied in situations when the athletes body was in need of rest.

Performance of eHealth Data Sources in Local Influenza Surveillance:A 5-Year Open Cohort Study

Background There is abundant global interest in using syndromic data from population-wide health information systems—referred to as eHealth resources—to improve infectious disease surveillance. Recently, the necessity for these systems to achieve two potentially conflicting requirements has been emphasized. First, they must be evidence-based; second, they must be adjusted for the diversity of populations, lifestyles, and environments. Objective The primary objective was to examine correlations between data from Google Flu Trends (GFT), computer-supported telenursing centers, health service websites, and influenza case rates during seasonal and pandemic influenza outbreaks. The secondary objective was to investigate associations between eHealth data, media coverage, and the interaction between circulating influenza strain(s) and the age-related population immunity. Methods An open cohort design was used for a five-year study in a Swedish county (population 427,000). Syndromic eHealth data were collected from GFT, telenursing call centers, and local health service website visits at page level. Data on mass media coverage of influenza was collected from the major regional newspaper. The performance of eHealth data in surveillance was measured by correlation effect size and time lag to clinically diagnosed influenza cases. Results Local media coverage data and influenza case rates showed correlations with large effect sizes only for the influenza A (A) pH1N1 outbreak in 2009 (r=.74, 95% CI .42-.90; P<.001) and the severe seasonal A H3N2 outbreak in 2011-2012 (r=.79, 95% CI .42-.93; P=.001), with media coverage preceding case rates with one week. Correlations between GFT and influenza case data showed large effect sizes for all outbreaks, the largest being the seasonal A H3N2 outbreak in 2008-2009 (r=.96, 95% CI .88-.99; P<.001). The preceding time lag decreased from two weeks during the first outbreaks to one week from the 2009 A pH1N1 pandemic. Telenursing data and influenza case data showed correlations with large effect sizes for all outbreaks after the seasonal B and A H1 outbreak in 2007-2008, with a time lag decreasing from two weeks for the seasonal A H3N2 outbreak in 2008-2009 (r=.95, 95% CI .82-.98; P<.001) to none for the A p H1N1 outbreak in 2009 (r=.84, 95% CI .62-.94; P<.001). Large effect sizes were also observed between website visits and influenza case data. Conclusions Correlations between the eHealth data and influenza case rates in a Swedish county showed large effect sizes throughout a five-year period, while the time lag between signals in eHealth data and influenza rates changed. Further research is needed on analytic methods for adjusting eHealth surveillance systems to shifts in media coverage and to variations in age-group related immunity between virus strains. The results can be used to inform the development of alert-generating eHealth surveillance systems that can be subject for prospective evaluations in routine public health practice.