| 1. |
- Cao, Yang, Associate Professor, 1972-, et al.
(författare)
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Using a Convolutional Neural Network to Predict Remission of Diabetes After Gastric Bypass Surgery : Machine Learning Study From the Scandinavian Obesity Surgery Register
- 2021
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Ingår i: JMIR Medical Informatics. - : JMIR Publications. - 2291-9694. ; 9:8
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Prediction of diabetes remission is an important topic in the evaluation of patients with type 2 diabetes (T2D) before bariatric surgery. Several high-quality predictive indices are available, but artificial intelligence algorithms offer the potential for higher predictive capability.OBJECTIVE: This study aimed to construct and validate an artificial intelligence prediction model for diabetes remission after Roux-en-Y gastric bypass surgery.METHODS: Patients who underwent surgery from 2007 to 2017 were included in the study, with collection of individual data from the Scandinavian Obesity Surgery Registry (SOReg), the Swedish National Patients Register, the Swedish Prescribed Drugs Register, and Statistics Sweden. A 7-layer convolution neural network (CNN) model was developed using 80% (6446/8057) of patients randomly selected from SOReg and 20% (1611/8057) of patients for external testing. The predictive capability of the CNN model and currently used scores (DiaRem, Ad-DiaRem, DiaBetter, and individualized metabolic surgery) were compared.RESULTS: In total, 8057 patients with T2D were included in the study. At 2 years after surgery, 77.09% achieved pharmacological remission (n=6211), while 63.07% (4004/6348) achieved complete remission. The CNN model showed high accuracy for cessation of antidiabetic drugs and complete remission of T2D after gastric bypass surgery. The area under the receiver operating characteristic curve (AUC) for the CNN model for pharmacological remission was 0.85 (95% CI 0.83-0.86) during validation and 0.83 for the final test, which was 9%-12% better than the traditional predictive indices. The AUC for complete remission was 0.83 (95% CI 0.81-0.85) during validation and 0.82 for the final test, which was 9%-11% better than the traditional predictive indices.CONCLUSIONS: The CNN method had better predictive capability compared to traditional indices for diabetes remission. However, further validation is needed in other countries to evaluate its external generalizability.
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| 2. |
- Alfonsson, Sven, 1977-
(författare)
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Impulsivity, Negative Mood, and Disordered Eating in Obesity
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Bariatric surgery is a life-altering procedure that leads to substantial weight loss for most patients with obesity. Psychiatric conditions that may interfere with eating behavior and other behavioral prescriptions after surgery are common. Disordered eating is an established risk factor for inferior weight loss but the effects of negative mood and impulsivity are largely unknown. This thesis aims to investigate the prevalence of and associations between these potential risk factors and eating behavior in bariatric surgery patients.Study I assessed the prevalence of adult Attention Deficits/Hyperactivity Disorder (ADHD) symptoms in bariatric surgery patients. Symptoms of adult ADHD were elevated compared to the normal population and associated with symptoms of disordered eating, anxiety, and depression.Study II investigated whether treatment with Behavioral Activation (BA) could ameliorate binge eating and other symptoms of disordered eating in patients with obesity and Binge Eating Disorder. The results showed that BA was effective in increasing activity levels and improving mood but not in ameliorating binge eating in these patients.Study III was a prospective study on disordered eating, symptoms of depression and anxiety, symptoms of adult ADHD, and alcohol risk consumption before surgery and at follow-up after 12 months. After controlling for age, no variable measured before surgery could predict weight loss after surgery. Disordered eating after surgery was associated with inferior weight loss in men and a subgroup of older female participants.The present thesis concludes that symptoms of adult ADHD are common among bariatric surgery patients and associated with disordered eating. There is no indication that symptoms of adult ADHD are associated with short-term inferior weight loss after surgery. However, adult ADHD may be a risk factor for postsurgical alcohol abuse. The treatment study showed no direct association among activity, mood, and binge eating. BA, while effective in improving mood, was found not to be an effective treatment for BED, at least in the short group format investigated.
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| 3. |
- Andreassen, Sissel
(författare)
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Life Situation, Information Needs, and Information Seeking in Patients with Oesophageal Cancer and their Family Members
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis explores the experiences of living with oesophageal cancer from the perspective of patients and family members. Also, their needs for information and how they seek information in relation to the illness were investigated. The thesis comprises one qualitative meta-analysis and three empirical studies including data from patients, family members, and health-care professionals. Paper I was a qualitative meta-analysis the aim of which was to extend knowledge about patients' and family members' experiences of living with oesophageal cancer and clinically similar cancer forms, mainly head and neck cancer. As a result of the thematic analysis we have shown that both patients and family members 'run into an unpredictable enemy'. Patients had to 'endure a fading body' Running into an unpredictable enemy and enduring a fading body led to -entering social silence' for patients and family members.The aim of paper II was to describe patients' experiences of living with oesophageal cancer and how they seek information in relation to the illness. Data was collected by qualitative interviews with thirteen patients and analysed by qualitative content analysis. The findings describe patients' experiences of receiving the diagnosis, their experiences of vague symptoms, and of existential concerns evoked by the illness. Undergoing investigations and treatment caused extreme tiredness. Patients experienced that the illness intruded upon their daily life. In order to manage the life-threatening illness- they sought information about the illness.The aim of paper III was to describe family members' experiences of living with a patient suffering from oesophageal cancer, their information needs and information seeking Data was collected by means of qualitative interviews with nine family members and analysed by qualitative content analysis. The findings describe that family members lacked awareness of the disease. When faced with the diagnosis, shock, stress, and disbelief were evoked . The cancer illness became intrusive into their everyday lives, routines, and life plans. Uncertainty about the course and prognosis of the disease was the main source of distress among them. In order to learn, obtain understanding for the illness, and manage this uncertainty, family members entrusted themselves to the experts and sought information from them.Paper IV was a pilot study the aim of which was to describe patients' and family members' information needs following a diagnosis of oesophageal cancer, their satisfaction with information obtained, and health-care professionals' perceptions concerning patients' and family members' information needs. Data was collected by means of a study-specific questionnaire and analysed with descriptive statistics. The results indicate that patients' and family members need for information following a diagnosis of oesophageal cancer was substantial and had not been adequately met by health-care professionals.In conclusion, the receipt of the diagnosis of oesophageal cancer was an abrupt change from feeling healthy with vague symptoms to having a life-threatening illness. The illness disrupts patients' and family members' social world and relationships, and the whole family is affected. For understanding and managing the illness, they sought information from health-care professionals, social networks, and various media
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| 4. |
- Cao, Yang, Associate Professor, 1972-, et al.
(författare)
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A Comparative Study of Machine Learning Algorithms in Predicting Severe Complications after Bariatric Surgery
- 2019
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Ingår i: Journal of Clinical Medicine. - : MDPI. - 2077-0383. ; 8:5
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Tidskriftsartikel (refereegranskat)abstract
- Background: Severe obesity is a global public health threat of growing proportions. Accurate models to predict severe postoperative complications could be of value in the preoperative assessment of potential candidates for bariatric surgery. So far, traditional statistical methods have failed to produce high accuracy. We aimed to find a useful machine learning (ML) algorithm to predict the risk for severe complication after bariatric surgery.Methods: We trained and compared 29 supervised ML algorithms using information from 37,811 patients that operated with a bariatric surgical procedure between 2010 and 2014 in Sweden. The algorithms were then tested on 6250 patients operated in 2015. We performed the synthetic minority oversampling technique tackling the issue that only 3% of patients experienced severe complications.Results: Most of the ML algorithms showed high accuracy (>90%) and specificity (>90%) in both the training and test data. However, none of the algorithms achieved an acceptable sensitivity in the test data. We also tried to tune the hyperparameters of the algorithms to maximize sensitivity, but did not yet identify one with a high enough sensitivity that can be used in clinical praxis in bariatric surgery. However, a minor, but perceptible, improvement in deep neural network (NN) ML was found.Conclusion: In predicting the severe postoperative complication among the bariatric surgery patients, ensemble algorithms outperform base algorithms. When compared to other ML algorithms, deep NN has the potential to improve the accuracy and it deserves further investigation. The oversampling technique should be considered in the context of imbalanced data where the number of the interested outcome is relatively small.
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| 5. |
- Cao, Yang, Associate Professor, 1972-, et al.
(författare)
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Deep Learning Neural Networks to Predict Serious Complications After Bariatric Surgery : Analysis of Scandinavian Obesity Surgery Registry Data
- 2020
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Ingår i: JMIR Medical Informatics. - : JMIR Publications. - 2291-9694. ; 8:5
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Obesity is one of today's most visible public health problems worldwide. Although modern bariatric surgery is ostensibly considered safe, serious complications and mortality still occur in some patients.OBJECTIVE: This study aimed to explore whether serious postoperative complications of bariatric surgery recorded in a national quality registry can be predicted preoperatively using deep learning methods.METHODS: Patients who were registered in the Scandinavian Obesity Surgery Registry (SOReg) between 2010 and 2015 were included in this study. The patients who underwent a bariatric procedure between 2010 and 2014 were used as training data, and those who underwent a bariatric procedure in 2015 were used as test data. Postoperative complications were graded according to the Clavien-Dindo classification, and complications requiring intervention under general anesthesia or resulting in organ failure or death were considered serious. Three supervised deep learning neural networks were applied and compared in our study: multilayer perceptron (MLP), convolutional neural network (CNN), and recurrent neural network (RNN). The synthetic minority oversampling technique (SMOTE) was used to artificially augment the patients with serious complications. The performances of the neural networks were evaluated using accuracy, sensitivity, specificity, Matthews correlation coefficient, and area under the receiver operating characteristic curve.RESULTS: In total, 37,811 and 6250 patients were used as the training data and test data, with incidence rates of serious complication of 3.2% (1220/37,811) and 3.0% (188/6250), respectively. When trained using the SMOTE data, the MLP appeared to have a desirable performance, with an area under curve (AUC) of 0.84 (95% CI 0.83-0.85). However, its performance was low for the test data, with an AUC of 0.54 (95% CI 0.53-0.55). The performance of CNN was similar to that of MLP. It generated AUCs of 0.79 (95% CI 0.78-0.80) and 0.57 (95% CI 0.59-0.61) for the SMOTE data and test data, respectively. Compared with the MLP and CNN, the RNN showed worse performance, with AUCs of 0.65 (95% CI 0.64-0.66) and 0.55 (95% CI 0.53-0.57) for the SMOTE data and test data, respectively.CONCLUSIONS: MLP and CNN showed improved, but limited, ability for predicting the postoperative serious complications after bariatric surgery in the Scandinavian Obesity Surgery Registry data. However, the overfitting issue is still apparent and needs to be overcome by incorporating intra- and perioperative information.
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| 6. |
- Dahlberg, Karuna, 1979-, et al.
(författare)
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Incident self-harm after bariatric surgery : A nationwide registry-based matched cohort study
- 2023
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Ingår i: Clinical Obesity. - : John Wiley & Sons. - 1758-8103 .- 1758-8111. ; 13:3
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Tidskriftsartikel (refereegranskat)abstract
- The aims of this study were to evaluate the longitudinal risk of self-harm and the risk factors for self-harm after bariatric surgery in patients and control subjects without prior self-harm. This observational cohort study was based on prospectively registered data. Patients 18–70 years at time of surgery, body mass index (BMI) > 30 kg/m2, who underwent a primary Roux-en-Y gastric bypass (RYGB) procedure or a primary sleeve gastrectomy between 2007 and 2019 were considered for inclusion. All patients who met the inclusion criteria were matched 1:10 to the general population in Sweden (69 492 patients vs. 694 920 controls). After excluding patients and controls with previous self-harm, a self-harm event occurred in 1408 patients in the surgical group (incidence rate (IR) 3.54/1000 person-years, 95% confidence interval (CI) 3.36–3.73) versus in 3162 patients in the control group (IR 0.81/1000 person-years, 95% CI 0.78–0.84), with a hazard ratio (HR) of 4.38 (95% CI 4.11–4.66, p < .001). Median follow-up time was 6.1 years. Risk factors were younger age, lower BMI, cardiovascular, and chronic obstructive pulmonary disease, all aspects of psychiatric comorbidities (except neuropsychiatric disorder), lower socioeconomic status, RYGB, lower health-related quality of life, lower postoperative weight loss, and not attending postoperative follow-up visits. Self-harm is clearly higher after bariatric surgery than in the general population. A qualitative follow-up may be particularly important for patients at increased risk.
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| 7. |
- Raoof, Mustafa, 1966-, et al.
(författare)
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Improvements of health-related quality of life 5 years after gastric bypass. What is important besides weight loss? A study from Scandinavian Obesity Surgery Register
- 2020
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Ingår i: Surgery for Obesity and Related Diseases. - : Elsevier. - 1550-7289 .- 1878-7533. ; 16:9, s. 1249-1257
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Obesity continues to increase in the world. It is strongly associated with morbidity, mortality, and decrease of health-related quality of life (HRQoL). Surgery is the most effective treatment for obesity, resulting in sustained weight loss and improvements of HRQoL. The aim of this study was to examine whether other factors, apart from weight loss, are associated with improvement in HRQoL scores between the preoperative visit and the 5-year follow-up.OBJECTIVES: To examine whether there are factors besides weight loss that affect the improvement of HRQoL from before to 5 years after gastric bypass surgery.SETTING: Large, nationwide, observational study with national quality and research registry.METHODS: Patients operated with a primary gastric bypass in Sweden between January 2008 and December 2012 were identified in the Scandinavian Obesity Surgery Register. Patients with HRQoL data available at both baseline and 5 years after surgery were included. Two HRQoL instruments, the RAND Short form-36 and the obesity-related problems scale, were used in the study.RESULTS: The study sample comprised 6998 patients (21% men). Differences in HRQoL change according to sex were minor. Younger patients showed greater improvements in physical health scales. In general linear regression model analyses, age and weight loss correlated significantly with improvement in HRQoL after 5 years. Patients treated medically for depression preoperatively (13%) experienced less improvement in HRQoL than patients without such treatment. Patients with postoperative complications (26%) had significantly less improvements in all aspects of HRQoL compared with those without any form of postoperative complication.CONCLUSION: The study confirmed the importance of weight loss for improvement in HRQoL after bariatric surgery. Preoperative medication for depression and suffering a complication during the 5-year follow-up period were associated with less improvement in HRQoL.
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| 8. |
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| 9. |
- Stenberg, Erik, 1979-, et al.
(författare)
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Association between attention deficit hyperactivity disorder and outcomes after metabolic and bariatric surgery : a nationwide propensity-matched cohort study
- 2023
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Ingår i: Surgery for Obesity and Related Diseases. - : Elsevier. - 1550-7289 .- 1878-7533. ; 19:2, s. 92-100
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The risks and benefits of metabolic and bariatric surgery for patients with attention deficit hyperactivity disorder (ADHD) remain to be investigated.OBJECTIVE: The aim of this study was to assess short- and long-term outcomes after metabolic and bariatric surgery in patients with previous ADHD compared with matched control individuals.SETTING: Registry based.METHODS: This 2-staged matched-cohort study included all adults with a body mass index of ≥30 kg/m2 who underwent primary Roux-en-Y gastric bypass or sleeve gastrectomy from 2007 until 2017 registered in the Scandinavian Obesity Surgery Registry. Patients with prescribed medication for ADHD were matched with control individuals without ADHD with a follow-up of up to 11 years after surgery.RESULTS: Among 1431 patients with ADHD and 2862 control individuals (mean body mass index, 42 kg/m2; mean age, 35 years), no difference in weight loss or follow-up attendance over 2 years was seen. ADHD was associated with a higher risk for early postoperative complications (odds ratio [OR] = 1.31; 95% confidence interval [CI], 1.05-1.63), self-harm (hazards ratio [HR] = 1.39; 95% CI, 1.11-1.75), and substance abuse (HR = 1.34; 95% CI, 1.16-1.55), while associations with overall mortality (HR = 1.42; 95% CI, .99-2.03), major adverse cardiovascular and cerebrovascular events (HR = 1.93; 95% CI, .98-3.83), and effects on obesity-related diseases were uncertain. ADHD was associated with a lower health-related quality of life in all aspects before surgery. These differences increased for mental and obesity-related aspects but remained unchanged over time for physical aspects.CONCLUSIONS: Compared with patients without ADHD, patients treated pharmacologically for ADHD experience similar weight loss and remission of obesity-related diseases without an increased risk for serious complications but report a lower health-related quality of life and have an increased risk of substance abuse and self-harm. This further emphasizes the need for close follow-up care for this group of individuals.
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| 10. |
- Stenberg, Erik, 1979-, et al.
(författare)
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Association between metabolic surgery and cardiovascular outcome in patients with hypertension : A nationwide matched cohort study
- 2020
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Ingår i: PLoS Medicine. - : Public Library of Science (PLoS). - 1549-1277 .- 1549-1676. ; 17:9
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Hypertension, together with obesity, is a leading cause of mortality and disability. Whilst metabolic surgery offers remission of several metabolic comorbidities, the effect for patients with hypertension remains controversial. The objective of the present study was to evaluate the effect of metabolic surgery on cardiovascular events and mortality on patients with morbid obesity (body mass index [BMI] ≥ 35 kg/m2) and hypertension.METHODS AND FINDINGS: We conducted a matched cohort study of 11,863 patients with morbid obesity and pharmacologically treated hypertension operated on with metabolic surgery and a matched non-operated-on control group of 26,199 subjects with hypertension (matched by age, sex, and area of residence) of varied matching ratios from 1:1 to 1:9, using data from the Scandinavian Obesity Surgery Register (SOReg), the Swedish National Patient Registers (NPR) for in-hospital and outpatient care, the Swedish Prescribed Drug Register, and Statistics Sweden. The main outcome was major adverse cardiovascular event (MACE), defined as first occurrence of acute coronary syndrome (ACS) event, cerebrovascular event, fatal cardiovascular event, or unattended sudden cardiac death. The mean age in the study group was 52.1 ± 7.46 years, with 65.8% being women (n = 7,810), and mean BMI was 41.9 ± 5.43 kg/m2. MACEs occurred in 379 operated-on patients (3.2%) and 1,125 subjects in the control group (4.5%). After adjustment for duration of hypertension, comorbidities, and education, a reduction in risk was seen in the metabolic surgery group (adjusted hazard ratio [HR] 0.73, 95% confidence intervals [CIs] 0.64-0.84, P < 0.001). The surgery group had lower risk for ACS events (adjusted HR 0.52, 95% CI 0.41-0.66, P < 0.001) and a tendency towards lower risk for cerebrovascular events (adjusted HR 0.81, 95% CI 0.63-1.01, P = 0.060) compared with controls. The main limitations with the study were the lack of information on BMI and history of smoking in the control group and the nonrandomised study design.CONCLUSION: Metabolic surgery on patients with morbid obesity and pharmacologically treated hypertension was associated with lower risk for MACEs and all-cause mortality compared with age- and sex-matched controls with hypertension from the general population.
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