| 1. |
- Barmpas, Petros, et al.
(författare)
-
A divisive hierarchical clustering methodology for enhancing the ensemble prediction power in large scale population studies : the ATHLOS project
- 2022
-
Ingår i: Health Information Science and Systems. - : Springer Science and Business Media LLC. - 2047-2501. ; 10:1
-
Tidskriftsartikel (refereegranskat)abstract
- The ATHLOS cohort is composed of several harmonized datasets of international groups related to health and aging. As a result, the Healthy Aging index has been constructed based on a selection of variables from 16 individual studies. In this paper, we consider additional variables found in ATHLOS and investigate their utilization for predicting the Healthy Aging index. For this purpose, motivated by the volume and diversity of the dataset, we focus our attention upon data clustering, where unsupervised learning is utilized to enhance prediction power. Thus we show the predictive utility of exploiting hidden data structures. In addition, we demonstrate that imposed computation bottlenecks can be surpassed when using appropriate hierarchical clustering, within a clustering for ensemble classification scheme, while retaining prediction benefits. We propose a complete methodology that is evaluated against baseline methods and the original concept. The results are very encouraging suggesting further developments in this direction along with applications in tasks with similar characteristics. A straightforward open source implementation for the R project is also provided (https://github.com/Petros-Barmpas/HCEP).
|
|
| 2. |
- Björkman, Ann-Sofi, et al.
(författare)
-
Sensitivity of DECT in ACL tears. A prospective study with arthroscopy as reference method
- 2022
-
Ingår i: Acta Radiologica Open. - : Sage Publications. - 2058-4601. ; 11:3
-
Tidskriftsartikel (refereegranskat)abstract
- Background: CT is often used for fracture evaluation following knee trauma and to diagnose ACL injuries would also be valuable. Purpose: To investigate the diagnostic accuracy of dual energy CT (DECT) for detection of ACL tears in acute and subacute knee injuries. Material and Methods: Patients with suspected ACL injury were imaged with DECT and MRI. Clinically blinded DECT images were independently read twice by two radiologists. ACL was classified as normal or abnormal. Arthroscopy served as reference method. Sensitivity and positive predictive value (PPV) were calculated, and diagnostic performance between DECT and MRI was assessed. Results: 48 patients (26 M, 22 F, mean age 23 years, range 15-37 years) were imaged with a mean of 25 days following trauma. Of these, 21 patients underwent arthroscopy with a mean of 195 days after trauma. Arthroscopy revealed 19 ACL tears and 2 ACLs with no tear. The combined sensitivity was 76.3% (95% CI 66.8-85.9) and 86.8 (95% CI 71.9-95.6) for DECT and MRI, respectively. There was no statistically significant difference between these two methods (p = .223). The positive predictive value (PPV) was 93.5 (95% CI 84.3-98.2) and 91.7 (95% CI 77.5-98.3) for DECT and MRI, respectively. Conclusion: DECT has lower sensitivity to detect an ACL rupture than MRI, but the difference is not statistically significant. The PPV is high in both methods.
|
|
| 3. |
- Björkman, Ann-Sofi, et al.
(författare)
-
Spectral photon-counting CT: Image quality evaluation using a metal-containing bovine bone specimen
- 2023
-
Ingår i: European Journal of Radiology. - : ELSEVIER IRELAND LTD. - 0720-048X .- 1872-7727. ; 168
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To find the optimal imaging parameters for a photon-counting detector CT (PCD-CT) and to compare it to an energy-integrating detector CT (EID-CT) in terms of image quality and metal artefact severity using a metal-containing bovine knee specimen. Methods: A bovine knee with a stainless-steel plate and screws was imaged in a whole-body research PCD-CT at 120 kV and 140 kV and in an EID dual-source CT (DSCT) at Sn150 kV and 80/Sn150 kV. PCD-CT virtual monoenergetic 72 and 150 keV images and EID-CT images processed with and without metal artefact reduction algorithms (iMAR) were compared. Four radiologists rated the visualisation of bony structures and metal artefact severity. The Friedman test and Wilcoxon signed-rank test with Bonferronis correction were used. P-values of <= 0.0001 were considered statistically significant. Distributions of HU values of regions of interest (ROIs) in artefact-affected areas were analysed.Results: PCD-CT 140 kV 150 keV images received the highest scores and were significantly better than EID-CT Sn150 kV images. PCD-CT 72 keV images were rated significantly lower than all the others. HU-value variation was larger in the 120 kV and the 72 keV images. The ROI analysis revealed no large difference between scanners regarding artefact severity.Conclusion: PCD-CT 140 kV 150 keV images of a metal-containing bovine knee specimen provided the best image quality. They were superior to, or as good as, the best EID-CT images; even without the presumed advantage of tin filter and metal artefact reduction algorithms. PCD-CT is a promising method for reducing metal artefacts.
|
|
| 4. |
- Guido, Davide, et al.
(författare)
-
Pain rates in general population for the period 1991-2015 and 10-years prediction : results from a multi-continent age-period-cohort analysis
- 2020
-
Ingår i: Journal of Headache and Pain. - : Springer Science and Business Media LLC. - 1129-2369 .- 1129-2377. ; 21:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background Pain is a common symptom, often associated with neurological and musculoskeletal conditions, and experienced especially by females and by older people. The aims of this study are to evaluate the temporal variations of pain rates among general populations for the period 1991-2015 and to project 10-year pain rates. Methods We used the harmonized dataset of ATHLOS project, which included 660,028 valid observations in the period 1990-2015 and we applied Bayesian age-period-cohort modeling to perform projections up to 2025. The harmonized Pain variable covers the content self-reported pain experienced at the time of the interview, with a dichotomous (yes or no) modality. Results Pain rates were higher among females, older subjects, in recent periods, and among observations referred to cohorts of subjects born between the 20s and the 60s. The 10-year projections indicate a noteworthy increase in pain rates in both genders and particularly among subjects aged 66 or over, for whom a 10-20% increase in pain rate is foreseen; among females only, a 10-15% increase in pain rates is foreseen for those aged 36-50. Conclusions Projected increase in pain rates will require specific interventions by health and welfare systems, as pain is responsible for limited quality of subjective well-being, reduced employment rates and hampered work performance. Worksite and lifestyle interventions will therefore be needed to limit the impact of projected higher pain rates.
|
|
| 5. |
- Ibounig, Thomas, et al.
(författare)
-
Concordance of shoulder symptoms and imaging findings: a protocol for the Finnish Imaging of Shoulder (FIMAGE) study
- 2023
-
Ingår i: BMJ open. - 2044-6055. ; 13:12
-
Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Shoulder pain is a substantial medical and socioeconomic problem in most societies, affecting the ability to work or carry out leisure time activities as well as subsequently influencing physical and psychological well-being. According to a nationwide survey in Finland, 27% of the population reported shoulder pain within the last 30 days. In clinical practice, imaging findings of structural abnormalities are typically thought to explain symptoms, even though such findings are also prevalent in asymptomatic individuals, particularly with increasing age. Overall, there is a paucity of high-quality evidence on the prevalence, clinical relevance and prognosis of 'abnormal' imaging findings of the shoulder.The aim of the Finnish Imaging of Shoulder (FIMAGE) study is fourfold: to assess (1) the prevalence of shoulder symptoms and the most common anatomical variants and imaging abnormalities of the shoulder; (2) the concordance between shoulder symptoms, function and imaging abnormalities; (3) the most important determinants of symptoms, function and imaging abnormalities; and (4) the course of shoulder complaints over 5 years. METHODS: The FIMAGE target population of 600 participants, aged 40-75 years, will be randomly selected from a nationally representative general population sample of 9922 individuals originally recruited for the Finnish Health 2000 Survey. On giving informed consent, the participants will be invited to a clinical visit that includes assessment of general health, shoulder symptoms, bilateral shoulder examination and imaging of both shoulders with plain radiography and MRI. ETHICS AND DISSEMINATION: The study has been approved by the Institutional Review Board of the Helsinki and Uusimaa Hospital District. The findings will be published according to the Strengthening the Reporting of Observational Studies in Epidemiology criteria.
|
|
| 6. |
- Marjonen, Heidi, et al.
(författare)
-
A Web Portal for Communicating Polygenic Risk Score Results for Health Care Use—The P5 Study
- 2021
-
Ingår i: Frontiers in Genetics. - : Frontiers Media SA. - 1664-8021. ; 12
-
Tidskriftsartikel (refereegranskat)abstract
- We present a method for communicating personalized genetic risk information to citizens and their physicians using a secure web portal. We apply the method for 3,177 Finnish individuals in the P5 Study where estimates of genetic and absolute risk, based on genetic and clinical risk factors, of future disease are reported to study participants, allowing individuals to participate in managing their own health. Our method facilitates using polygenic risk score as a personalized tool to estimate a person’s future disease risk while offering a way for health care professionals to utilize the polygenic risk scores as a preventive tool in patient care.
|
|
| 7. |
- Nummela, Mari T., et al.
(författare)
-
Costal cartilage fractures in blunt polytrauma patients - a prospective clinical and radiological follow-up study
- 2022
-
Ingår i: Emergency Radiology. - : SPRINGER HEIDELBERG. - 1070-3004 .- 1438-1435. ; 29:5, s. 845-854
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose To assess the healing of costal cartilage fractures (CCFX) in patients with blunt polytrauma with follow-up imaging and clinical examination. Effect on physical performance and quality of life (QoL) was also evaluated. Methods The study group comprised twenty-one patients with diagnosed CCFX in trauma CT. All the patients underwent MRI, ultrasound, ultra-low-dose CT examinations, and clinical status control. The patients completed QoL questionnaires. Two radiologists evaluated the images regarding fracture union, dislocation, calcifications, and persistent edema at fracture site. An attending trauma surgeon clinically examined the patients, with emphasis on focal tenderness and ribcage mobility. Trauma registry data were accessed to evaluate injury severity and outcome. Results The patients were imaged at an average of 34.1 months (median 36, range 15.8-57.7) after the initial trauma. In 15 patients (71.4%), CCFX were considered stable on imaging. Cartilage calcifications were seen on healed fracture sites in all the patients. The fracture dislocation had increased in 5 patients (23.8%), and 1 patient (4.8%) showed signs of a non-stable union. Four patients (19.0%) reported persistent symptoms from CCFX. Conclusion Non-union in CCFX is uncommon but may lead to decreased stability and discomfort. Both clinical and radiological examinations play an important part in the post-traumatic evaluation of CCFX. CT and MRI visualize the healing process, while dynamic ultrasound may reveal instability. No significant difference in QoL was detected between patients with radiologically healed and non-healed CCFX. Post-traumatic disability was mostly due to other non-thoracic injuries.
|
|
| 8. |
- Sanchez-Niubo, Albert, et al.
(författare)
-
Development of a common scale for measuring healthy ageing across the world : results from the ATHLOS consortium
- 2021
-
Ingår i: International Journal of Epidemiology. - : Oxford University Press (OUP). - 0300-5771 .- 1464-3685. ; 50:3, s. 880-892
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Research efforts to measure the concept of healthy ageing have been diverse and limited to specific populations. This diversity limits the potential to compare healthy ageing across countries and/or populations. In this study, we developed a novel measurement scale of healthy ageing using worldwide cohorts.METHODS: In the Ageing Trajectories of Health-Longitudinal Opportunities and Synergies (ATHLOS) project, data from 16 international cohorts were harmonized. Using ATHLOS data, an item response theory (IRT) model was used to develop a scale with 41 items related to health and functioning. Measurement heterogeneity due to intra-dataset specificities was detected, applying differential item functioning via a logistic regression framework. The model accounted for specificities in model parameters by introducing cohort-specific parameters that rescaled scores to the main scale, using an equating procedure. Final scores were estimated for all individuals and converted to T-scores with a mean of 50 and a standard deviation of 10.RESULTS: A common scale was created for 343 915 individuals above 18 years of age from 16 studies. The scale showed solid evidence of concurrent validity regarding various sociodemographic, life and health factors, and convergent validity with healthy life expectancy (r = 0.81) and gross domestic product (r = 0.58). Survival curves showed that the scale could also be predictive of mortality.CONCLUSIONS: The ATHLOS scale, due to its reliability and global representativeness, has the potential to contribute to worldwide research on healthy ageing.
|
|
| 9. |
- Sipilä, Pyry N., et al.
(författare)
-
Severe Infection and Risk of Cardiovascular Disease : A Multicohort Study
- 2023
-
Ingår i: Circulation. - : American Heart Association. - 0009-7322 .- 1524-4539. ; 147:21, s. 1582-1593
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The excess risk of cardiovascular disease associated with a wide array of infectious diseases is unknown. We quantified the short- and long-term risk of major cardiovascular events in people with severe infection and estimated the population-attributable fraction. Methods: We analyzed data from 331 683 UK Biobank participants without cardiovascular disease at baseline (2006-2010) and replicated our main findings in an independent population from 3 prospective cohort studies comprising 271 329 community-dwelling participants from Finland (baseline 1986-2005). Cardiovascular risk factors were measured at baseline. We diagnosed infectious diseases (the exposure) and incident major cardiovascular events after infections, defined as myocardial infarction, cardiac death, or fatal or nonfatal stroke (the outcome) from linkage of participants to hospital and death registers. We computed adjusted hazard ratios (HRs) and 95% CIs for infectious diseases as short- and long-term risk factors for incident major cardiovascular events. We also calculated population-attributable fractions for long-term risk. Results: In the UK Biobank (mean follow-up, 11.6 years), 54 434 participants were hospitalized for an infection, and 11 649 had an incident major cardiovascular event at follow-up. Relative to participants with no record of infectious disease, those who were hospitalized experienced increased risk of major cardiovascular events, largely irrespective of the type of infection. This association was strongest during the first month after infection (HR, 7.87 [95% CI, 6.36-9.73]), but remained elevated during the entire follow-up (HR, 1.47 [95% CI, 1.40-1.54]). The findings were similar in the replication cohort (HR, 7.64 [95% CI, 5.82-10.03] during the first month; HR, 1.41 [95% CI, 1.34-1.48] during mean follow-up of 19.2 years). After controlling for traditional cardiovascular risk factors, the population-attributable fraction for severe infections and major cardiovascular events was 4.4% in the UK Biobank and 6.1% in the replication cohort. Conclusions: Infections severe enough to require hospital treatment were associated with increased risks for major cardiovascular disease events immediately after hospitalization. A small excess risk was also observed in the long-term, but residual confounding cannot be excluded.
|
|
| 10. |
- Söderman, Tomas
(författare)
-
Radiological methods in rheumatoid arthritis and osteoarthritis
- 2022
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The dissertation's theme is the critical role of radiology when evaluating two different groups of patients. Firstly, patients with rheumatoid arthritis (RA) of the cervical spine were studied to evaluate upper spine instability with dynamic computed tomography (CT). Secondly, after anterior cruciate ligament (ACL) reconstruction, patients with a long-term follow-up were studied to evaluate osteoarthritis (OA). In paper I, 21 consecutive patients with atlantoaxial subluxation due to RA planned for atlantoaxial fusion were included. Radiographs were obtained in neutral and flexed positions, CT and Magnetic Resonance Imaging (MRI) was performed with the neck in the neutral position and CT also in flexion. Radiographs and CT measurements of atlantoaxial subluxation correlated but were larger using radiographs than CT in flexion. The spinal cord compression was significantly worse at CT obtained in flexed position than MRI in the neutral position. In papers II and III, the cohort consisted of 60 patients, and in paper IV, 73 patients. Mean follow-up was 31 years after ACL reconstruction. MRI, radiographs, International Knee Documentation Committee (IKDC) clinical assessment, Knee injury Osteoarthritis Outcome Score (KOOS), Short Form-36 (SF-36), Tegner Activity Scale, and KT-1000 arthrometer were used in order to evaluate the patients. Thirty-three patients showed an intact ACL graft, and 40 a ruptured ACL graft. Forty-nine patients had tibiofemoral OA, and 28 patients had patellofemoral OA. Patients with ruptured ACL grafts had more OA in the medial tibiofemoral compartment than those with an intact ACL graft. Sport and Recreation Function and Quality of life scores were higher in patients with an intact ACL graft than those with a ruptured ACL graft. All subscales of KOOS were higher in the group without OA. KOOS Quality of life score was lower than for a control group of men. The IKDC overall clinical assessment was worse in patients with a ruptured ACL graft. This thesis suggests that radiographs remain the primary imaging method for evaluating atlantoaxial instability. However, CT in flexed position is useful in the preoperative imaging workup. Patients with a ruptured ACL graft presented with more OA of the medial tibiofemoral compartment than those with an intact graft. Patients with an intact ACL graft and those without OA reported higher sports activity and recreation and better knee-related Quality of life. Knee-related Quality of life in the study group was reduced compared to a reference group.
|
|
