The stenotic carotid artery plaque : prevalence, risk factors and relations to clinical disease : the Tromsø study

Stroke is the second leading cause of death in the world and is responsible for a high percentage of major disability, requiring substantial resources spent on care and rehabilitation. Atherosclerosis due to lipid accumulation in the vessel wall with formation of stenotic atheromatous plaques in the carotid bifurcation and/or the internal carotid artery is an important cause of stroke. In 1991, two large, multi-center trials reported that carotid endarterectomy was of benefit to patients with a degree of stenosis above 70%, and thus showed that the degree of stenosis was a major risk factor for ipsilateral stroke. However, it is well known that many high-grade stenoses remain stable and never cause cerebrovascular events, while others develop rapidly and produce serious, potentially life-threatening disease. While the majority of patients presenting with transient ischemic attack (TIA) and stroke has an ipsilateral carotid lesion, only about half of them have a hemodynamically significant carotid stenosis. Only 5-15% of strokes are heralded by a TIA. This has led to a search for additional risk factors which might help identify the individuals with a high risk for stroke

Macular thickness in healthy eyes of adults (N = 4508) and relation to sex, age and refraction the Tromsø Eye Study (2007-2008)

PURPOSE: To provide sex-stratified normative data on retinal thickness and study the relationship with sex, age and refractive status.METHODS: Population-based study including 2617 women and 1891 men, aged 38-87 (mean 61 ± 8) years, without diabetes, glaucoma and retinal diseases, and spherical equivalent refraction (SER) within ±6 dioptres. Retinal thickness was measured with optical coherence tomography (spectral domain Cirrus HD-OCT).RESULTS: Women had thinner retina than men. Retinal thickness was significantly associated with refraction, where mean change in retinal thickness per 1 D increase in SER was -1.3 (0.2) μm in the fovea, 0.7 (0.1) μm in the pericentral ring and 1.4 (0.1) μm in the peripheral ring. In the fovea, there was a non-monotonic curved relationship between retinal thickness and age in both sexes with a maximum at about 60 years (p &lt; 0.001). In the pericentral ring, the mean reduction in retinal thickness per 10-year increase was 2.7 (0.3) μm in women and 4.0 (0.4) μm in men and corresponding results in the peripheral ring were 2.3 (0.3) μm in women and 2.6 (0.4) μm in men. In both regions, there was evidence for a nonlinear pattern with an increased rate of change with higher age. There was a significant interaction between sex and age for retinal thickness of the pericentral ring (p = 0.041).CONCLUSION: Women had thinner retina than men, and thickness varied with refractive status. Retinal thickness was associated with age in all macular regions, and the rate of change in retinal thickness varied at different ages.</p

Population distribution of traditional and the emerging cardiovascular risk factors carotid plaque and IMT: the REFINE-Reykjavik study with comparison with the Tromsø study

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked FilesOBJECTIVES: Population statistics for carotid plaque and cardiovascular risk factors reported in scientific journals are usually presented as averages for the population or age and sex adjusted, rather than sex and age groups. Important population differences about atherosclerosis and cardiovascular risk factors may thus be missed. We compare the distribution of cardiovascular risk factors, carotids plaque and carotid intima-media thickness (CIMT) in two population-based studies. METHODS: Carotid artery atherosclerotic plaque prevalence and risk factors levels for cardiovascular disease by sex in 5-year age groups from the Risk Evaluation For Infarct Estimates Reykjavik study (REFINE-Reykjavik study) were compared with data from the Tromsø 6 study. RESULTS: The threshold of carotid plaque presence in the Tromsø 6 study fell between minimal and moderate plaque defined in the REFINE-Reykjavik study reflecting carotid plaque prevalence. The prevalence of minimal carotid plaque in the REFINE-Reykjavik study was 47% in men (40-69 years old) and 38% in women and 11% in men and 7% in women of moderate plaque. The prevalence of any plaque in the Tromsø 6 study was 35% in men and 27% in women. The mean (CIMT) was similar in the studies. In the Tromsø 6 study mean systolic blood pressure was 8 mm Hg higher in men and 10 mm Hg higher in women, mean low-density lipoprotein was 0.5 mmol/L higher in men and 0.3 mmol/L higher in women and the prevalence of smoking was 4% higher in men and 9% higher in women. However, body mass index was 0.8 kg/m2 higher in men and 0.9 kg/m2 in women in the REFINE-Reykjavik study. CONCLUSION: Comparison between Iceland and Norway revealed differences in the prevalence of carotid plaque, which was assumed to be due to different definition of plaque. However, clinically significant differences in conventional cardiovascular risk factors were seen. This underscores the importance of detailed comparison of population data across different populations.RANNIS (The Icelandic Centre for Research) Hjartavernd (Icelandic Heart Association

Trends in prevalence of ultrasound-assessed carotid atherosclerosis in a general population over time. The Tromsø Study 1994-2016

Background: During the past decades, there has been a shift in risk factor levels in many high-income countries, with decrease in smoking, blood pressure and cholesterol levels, while body mass index, obesity and diabetes increase. The diverging trends may have opposite effects on prevalence of atherosclerosis. We aimed to assess carotid plaque prevalence and the association with risk factor levels in a general population over a period of 22 years. Methods: Prevalence of plaque, number of plaques and total plaque area in the carotid arteries were assessed in three repeated cross-sectional surveys of the population-based Tromsø Study from 1994 through 2016. The number of participants from the first to the last survey was 6362, 7069 and 3021. All surveys included physical examinations, questionnaires, and blood samples. Multivariable logistic regression analysis models were fitted to assess the relationship between risk factors and carotid plaque. Results: We found no significant change in plaque burden over a period of 22 years, neither when measured as plaque presence, plaque number or total plaque area. Plaques were more frequent in men (70%) than in women (59.4%) and increased by age. Systolic blood pressure and smoking increased, while BMI and diabetes decreased over time both in participants with and without plaque. Most risk factors remained higher in participants with plaque than in plaque- free participants while cholesterol levels decreased and reached similar levels in both groups. Age, male sex, systolic blood pressure, smoking, diabetes and HDL cholesterol (inverse) were associated with plaque prevalence. Conclusions: Plaque prevalence remained stable in the observation period. Favorable reductions in systolic blood pressure, cholesterol and smoking may have been partly counteracted by increased diabetes prevalence. Risk factor levels remained higher in participants with plaque than in plaque-free participants, indicating a potential for further improvement in primary prevention of carotid atherosclerosis

Prevalence of intracranial artery stenosis in a general population using 3D-time of flight magnetic resonance angiography

Background: Data on prevalence of intracranial artery stenosis (ICAS) in Western populations is sparse. The aim of the study was to assess the prevalence and risk factors for ICAS in a mainly Caucasian general population. Methods: We assessed the prevalence of ICAS in 1847 men and women aged 40 to 84 years who participated in a cross-sectional population-based study, using 3-dimensional time-of-flight 3 Tesla magnetic resonance angiography. ICAS was defined as a focal luminal flow diameter reduction of ≥50 %. The association between cardiovascular risk factor levels and ICAS was assessed by multivariable regression analysis. Results: The overall prevalence of ICAS was 6.0 % (95 % confidence interval (CI) 5.0–7.2), 4.3 % (95 % CI 3.1–5.7) in women and 8.0 % (95 % CI 6.3–10.0) in men. The prevalence increased by age from 0.8 % in 40-54 years age group to 15.2 % in the 75-84 years age group. The majority of stenoses was located to the internal carotid artery (52.2 %), followed by the posterior circulation (33.1 %), the middle cerebral artery (10.8 %) and the anterior cerebral artery (3.8 %). The risk of ICAS was independently associated with higher age, male sex, hypertension, hyperlipidemia, diabetes mellitus, current smoking and higher BMI. Conclusions: The prevalence of ICAS in a general population of Caucasians was relatively high and similar to the prevalence of extracranial internal carotid artery stenosis in previous population-based studies

Wake-up stroke and unknown-onset stroke; occurrence and characteristics from the nationwide Norwegian Stroke Register

Introduction: Population-based knowledge of the characteristics of wake-up stroke and unknown-onset stroke is limited. We compared occurrence and characteristics of ischaemic and haemorrhagic wake-up stroke, unknown-onset stroke and known-onset stroke in a nationwide register-based study. Patients and methods: We included patients registered in the Norwegian Stroke Register from 2012 through 2019. Age, sex, risk factors, clinical characteristics, acute stroke treatment and discharge destination were compared according to stroke type and time of onset. Results: Of the 60,320 patients included, 11,451 (19%) had wake-up stroke, 11,098 (18.4%) had unknown time of onset and 37,771 (62.6%) had known symptom onset. The proportion of haemorrhagic stroke was lower among wakeup stroke patients (1107/11,451, 9.7%, 95% CI: 9.1–10.2) than for known-onset stroke (5230/37,771, 13.8%, 95% CI: 13.5–14.2) and for unknown-onset stroke (1850/11,098, 16.7%, 95% CI: 16.0–17.4). Mild stroke (NIHSS Discussion and conclusions: Ischaemic wake-up strokes shared baseline characteristics with known-onset strokes, but tended to be milder. Ischaemic unknown-onset stroke patients differed significantly from wake-up stroke, emphasising the importance of considering them as separate entities

Data from national health registers as endpoints for the Tromsø Study: Correctness and completeness of stroke diagnoses

Aim: To assess whether stroke diagnoses in national health registers are sufficiently correct and complete to replace manual collection of endpoint data for the Tromsø Study, a population-based epidemiological study. Method: Using the Tromsø Study Cardiovascular Disease Register for 2013–2014 as the gold standard, we calculated correctness (defined as positive predictive value, PPV) and completeness (defined as sensitivity) of stroke cases in four different data subsets derived from the Norwegian Patient Register and the Norwegian Stroke Register. We calculated the sensitivity and PPV with 95% confidence intervals (CIs) assuming a normal approximation of the binomial distribution. Results: In the Norwegian Stroke Register we found a sensitivity of 79.8% (95% CI 74.2–85.4) and a PPV of 97.5% (95% CI 95.1–99.9). In the Norwegian Patient Register the sensitivity was 86.4% (95% CI 81.6–91.1) and the PPV was 84.2% (95% CI 79.2–89.2). The overall highest levels were found in a subset based on a linkage between the Norwegian Stroke Register and the Norwegian Patient Register, with a sensitivity of 88.9% (95% CI 84.5–93.3), and a PPV of 89.3% (95% CI 85.0–93.6). Conclusions: Data from the Norwegian Patient Register and from the linked data set between the Norwegian Patient Register and the Norwegian Stroke Register had acceptable levels of correctness and completeness to be considered as endpoint sources for the Tromsø Study Cardiovascular Disease Register. The benefits of using data from national registers as endpoints in epidemiological studies must be weighed against the impact of potentially decreased data quality

Neuropsychological functions of verbal recall and psychomotor speed significantly affect pain tolerance

Source at https://doi.org/10.1002/ejp.1437.Background - Effects from cognitive performance on pain tolerance have been documented, however, sample sizes are small and confounders often overlooked. We aimed to establish that performance on neuropsychological tests was associated with pain tolerance, controlling for salient confounders. Methods - This was a cross‐sectional study nested within the Tromsø‐6 survey. Neuropsychological test performance and the cold pressor test were investigated in 4,623 participants. Due to significant interaction with age, participants were divided into three age groups (<60, ≥60 to <70 and ≥70 years). Cox proportional hazard models assessed the relationship between neuropsychological tests and cold pressure pain tolerance, using hand‐withdrawal as event. The fully adjusted models controlled for sex, education, BMI, smoking status, exercise, systolic blood pressure, sleep problems and mental distress. Results - In the adjusted models, participants aged ≥70 years showed a decreased hazard of hand withdrawal of 18% (HR 0.82, 95% CI (0.73, 0.92) per standard deviation on immediate verbal recall, and a decreased hazard of 23% (HR 0.77, 95% CI (0.65, 0.08) per standard deviation on psychomotor speed. Participants aged ≥60 to <70 years had a significant decreased hazard of 11% (HR 0.89, 95% CI (0.80, 0.98) per standard deviation on immediate word recall. In participants aged <60 years, there was a decreased hazard of 14% (HR 0.86 95% CI: 0.76, 0.98), per standard deviation on psychomotor speed. Conclusion - Better performance on neuropsychological tests increased pain tolerance on the cold pressor test. These exposure effects were present in all age groups. Significance - This paper describes substantial associations between cognitive functioning and cold pressor tolerance in 4,623 participants. Reduced psychomotor speed and poor verbal recall gave greater odds for hand‐withdrawal on the cold pressor task. The associations were stronger in older participants, indicating an interaction with age

Geografiske forskjeller i trombolysebehandling ved akutt hjerneinfarkt

Bakgrunn - Trombolysebehandling tidligst mulig etter symptomstart påvirker behandlingsresultatet ved akutt hjerneinfarkt. Målet med studien var å kartlegge om avstanden fra sykehus påvirker trombolysetilbudet ved akutt hjerneinfarkt ved Universitetssykehuset Nord-Norge Tromsø. Materiale og metode - I denne prospektive kvalitetsstudien inkluderte vi 231 pasienter innlagt med akutt hjerneinfarkt i perioden 1.1.2019–31.12.2019 ved Universitetssykehuset Nord-Norge. Pasientene ble inndelt i to grupper basert på transporttid i bil til sykehuset ved symptomstart: byutvalget (≤ 30 minutter) og distriktsutvalget (> 30 minutter). Informasjon om pasientkarakteristika, trombolysebehandling og funksjonsnivå ble innhentet fra Norsk hjerneslagregister, og prehospitale forløpstider ble hentet fra Akuttmedisinsk informasjonssystem. Utfallsmål var trombolyseandel og tid fra symptomstart til trombolysebehandling. Resultater - Ved symptomstart befant 108 av de 231 pasientene seg i byområdet og 123 i distriktet. Byutvalget inkluderte færre menn (54 % vs. 68 %), lavere andel med godt funksjonsnivå (skår 0–1 med modifisert Rankin-skala) før symptomstart (58 % vs. 73 %) og færre pasienter innlagt via legevakt (10 % vs. 28 %) enn distriktsutvalget. Andelen som mottok trombolysebehandling, var 38 % i byutvalget og 23 % i distriktsutvalget. Byutvalget mottok behandlingen gjennomsnittlig 75 minutter tidligere enn distriktsutvalget. Fortolkning - Funnene tyder på at pasienter med større avstand til sykehus ved symptomstart får sjeldnere og senere trombolysebehandling, og har dermed lavere sannsynlighet for god behandlingseffekt. Direkte tilgang til desentralisert trombolyse vil kunne forbedre behandlingstilbudet for hjerneslagpasienter

Prevalence of unruptured intracranial aneurysms: impact of different definitions-the Tromsø Study

Background - Management of incidental unruptured intracranial aneurysms (UIAs) remains challenging and depends on their risk of rupture, estimated from the assumed prevalence of aneurysms and the incidence of aneurysmal subarachnoid haemorrhage. Reported prevalence varies, and consistent criteria for definition of UIAs are lacking. We aimed to study the prevalence of UIAs in a general population according to different definitions of aneurysm. Methods - Cross-sectional population-based study using 3-dimensional time-of-flight 3 Tesla MR angiography to identify size, type and location of UIAs in 1862 adults aged 40–84 years. Size was measured as the maximal distance between any two points in the aneurysm sac. Prevalence was estimated for different diameter cutoffs (≥1, 2 and 3 mm) with and without inclusion of extradural aneurysms. Results - The overall prevalence of intradural saccular aneurysms ≥2 mm was 6.6% (95% CI 5.4% to 7.6%), 7.5% (95% CI 5.9% to 9.2%) in women and 5.5% (95% CI 4.1% to 7.2%) in men. Depending on the definition of an aneurysm, the overall prevalence ranged from 3.8% (95% CI 3.0% to 4.8%) for intradural aneurysms ≥3 mm to 8.3% (95% CI 7.1% to 9.7%) when both intradural and extradural aneurysms ≥1 mm were included. Conclusion - Prevalence in this study was higher than previously observed in other Western populations and was substantially influenced by definitions according to size and extradural or intradural location. The high prevalence of UIAs sized <5 mm may suggest lower rupture risk than previously estimated. Consensus on more robust and consistent radiological definitions of UIAs is warranted