Annals Thoracic Surgery, Author Interviews, Heart Disease, Technology / 24.11.2015
LVAD Use in CHF Increases, In-Hospital Mortality Decreases
MedicalResearch.com Interview with:
Neeraj Shah, MD, MPH
Cardiology Fellow
Department of Cardiology
Lehigh Valley Health Network
Allentown, PA.
Medical Research: What is the background for this study? What are the main findings?
Dr. Shah: Congestive heart failure (CHF) affects 5.8 million Americans, with prevalence as high as 10% in individuals aged 65 years or more. There are long wait times for heart transplants. Left ventricular assist devices (LVADs) have been shown to significantly improve outcomes in end stage CHF patients. In the current situation of limited donor hearts, the utilization of LVAD technology is likely to increase over time. Moreover, the LVAD technology has improved considerably over time. The first generation devices were bulky and pulsatile in nature and of limited durability, whereas the second and third generation devices are smaller, longer lasting and exhibit “continuous flow”. The United States Food and Drug Administration (FDA) approved continuous flow devices in 2008. Presently, continuous flow devices account for over 95% of LVAD implants. Our aim was to examine the trends in utilization, in-hospital mortality, procedure related complications and cost of care after LVAD implantation from 2005 to 2011, and to study any differences in the pulsatile flow era from 2005-2007, compared to continuous flow era from 2008-2011. We used the Nationwide Inpatient Sample (NIS), which the largest all-payer US national hospitalization database, for our study. We identified LVAD implants using International Classification of Disease, 9th edition (ICD-9) procedure code 37.66. NIS data showed that there were 2,038 LVAD implantations from 2005 to 2011. LVAD utilization increased from 127 procedures in 2005 to 506 procedures in 2011, with a sharp increase after the year 2008 (from 149 procedures in 2007 to 257 procedures in 2008). In-hospital mortality associated with LVAD implantation decreased considerably from 47.2% in 2005 to 12.7% in 2011 (p<0.001), with a sharp decline in mortality after the year 2008 (from 38.9% in 2007 to 19.5% in 2008). Average length of stay (LOS) decreased from 44 days in the pulsatile-flow era to 36 days in the continuous-flow era. Cost of hospitalization increased from $194,380 in 2005 to $234,808 in 2011 but remained steady from 2008 to 2011. There was a trend of increased incidence of major bleeding and thromboembolism and decreased incidence of infectious and iatrogenic cardiac complications in the continuous-flow era. Thus, there has been a considerable increase in utilization of LVADs and decline in in-hospital mortality and LOS after LVAD implantation. These changes strongly coincide with US FDA approval of continuous flow devices in 2008.
Dr. McNaughton[/caption]
MedicalResearch.com Interview with:
Candace D. McNaughton, MD MPH FACEP
Assistant Professor
Emergency Medicine Research
Department of Emergency Medicine, Research Division
Vanderbilt University Medical Center
Medical Research: What is the background for this study? What are the main findings?
Dr. McNaughton: Hypertension, or high blood pressure, affects 1/3rd of adults in the United States and more than 1 billion people worldwide. It is also the #1 risk factor for cardiovascular disease such as heart attack and stroke, so it is very important to treat.
The burden of hypertension in the emergency department is not well understood. The ER is not usually thought of as a place where perhaps we could or should be addressing hypertension; that has traditionally be left up to primary care providers. Through this study, our goals were to gain a better understanding of how many ER visits were either related to hypertension or were solely because of hypertension, and to determine whether this changed from 2006 to 2012.
We found that 
Dr. Tianhua He[/caption]
MedicalResearch.com Interview with:
Dr. Tianhua He MD
Beijing China, 100005
Medical Research: What is the background for this study? What are the main findings?
Response: The prevalence of Hepatitis C (HCV) infection is high (17%) in US prisons. And about 30% of all HCV-infected persons in US spend part of the year in correctional facilities.
However, most state prisons offer no routine screening for Hepatitis C. Undiagnosed and untreated inmates, after releasing, will contribute to the spread of the disease in society. HCV infection is now the leading cause of liver cancer, and the most common indication for liver transplant. With the recently launched highlyy effective antiviral drugs, previous studies have shown that treating infected prisoners was cost-effective. However, no studies yet have evaluated the effect of interventions including screening and treatment among prisoners on prevention of 
Dr. Gunderson[/caption]
MedicalResearch.com Interview with:
Erica P. Gunderson, PhD, MPH, MS, RD
Senior Research Scientist, Division of Research, Cardiovascular and Metabolic Conditions Section
Kaiser Permanente Northern California
Oakland, CA 94612
Medical Research: What is the background for this study?
Dr. Gunderson: Gestational diabetes mellitus (GDM) is a disorder of glucose tolerance affecting 5-9 percent of all U.S. pregnancies (approximately 250,000 annually), with a 7-fold higher risk of progression to type 2 diabetes. Strategies during the postpartum period for prevention of diabetes focus on modification of lifestyle behaviors, including dietary intake and physical activity to promote weight loss.
Lactation is a modifiable postpartum behavior that improves glucose and lipid metabolism, and increases insulin sensitivity, with favorable metabolic effects that persist post-weaning. Despite these metabolic benefits, evidence that lactation prevents type 2 diabetes remains inconclusive, particularly among women with 
Dr. Aaron White[/caption]
MedicalResearch.com Interview with:
Aaron White, PhD
Senior Scientific Advisor to the Director
Office of the Director
National Institute on Alcohol Abuse and Alcoholism
National Institutes of Health
Bethesda, MD
Medical Research: What is the background for this study? What are the main findings?
Dr. White: Recent studies and anecdotal evidence suggest that alcohol use by women in the United States might be on the rise and that long-standing gender gaps in drinking and related consequences might be narrowing. Using data from the National Survey on Drug Use and Health, we found that differences in the drinking patterns of females and males ages 12+ narrowed between 2002 and 2012 for current drinking (drinking at least once in the last 30 days), number of drinking days per month, past year DSM-IV alcohol abuse, and past-year driving under the influence of alcohol. For instance, the percentage of women who drank in the previous 30 days rose from 44% to 48%, while for men the percentage decreased from 57% to 56%. Average 
Dr. Villanti[/caption]
MedicalResearch.com Interview with:
Dr. Andrea C. Villanti PhD, MPH
Director, Regulatory Science and Policy Schroeder Institute for Tobacco Research and Policy Studies at Truth Initiative
Washington, DC 20001
Medical Research: What is the background for this study? What are the main findings?
Dr. Villanti: Awareness, interest, and use of electronic cigarettes (e-cigarettes) have increased since the products were introduced in the U.S. in 2006. Between 2012 and 2013, 8.3% of young adults reported current e-cigarette use compared to 4.2% of adults overall. One factor likely driving 
Dr. Chunsheng Wang[/caption]
MedicalResearch.com Interview with:
Chunsheng Wang, MD
Department of Cardiovascular Surgery, Shanghai Cardiovascular Institution
and Zhongshan Hospital
Fudan University, Shanghai, China
Medical Research: What is the background for this study? What are the main findings?
Dr. Wang: Transcatheter aortic valve replacement (TAVR) has been widely used in high-risk patients for surgical aortic valve replacement. However, the majority of the TAVR devices were designed for aortic valve stenosis with significant valve calcification. For most of these devices, predominant aortic regurgitation remained to be a technological challenge because of questionable anchoring, which can result in a high incidence of valve migration and paravalvular leak. Consequently, the guidelines from the United States and the Europe suggest that candidates with predominant aortic regurgitation (>grade 3+) or noncalcified valve should not undergo 
Dr. Newton[/caption]
MedicalResearch.com Interview with:
Paul K Newton PhD
Professor of Aerospace & Mechanical Engineering, Mathematics, and Norris Comprehensive Cancer Center
USC Viterbi
University of Southern California
University Park Campus
Los Angeles, CA 90089-4012
Medical Research: What is the background for this study? What are the main findings?
Dr. Newton: We obtained a longitudinal data set of 446 breast cancer patients from Memorial Sloan Kettering Cancer Center, tracked from 1975 to 2009.
All of the patients had primary breast cancer at the time they entered, with no metastatic tumors. All subsequently developed metastatic breast cancer.
From this time-resolved data set, we first developed what we called tree-ring diagrams showing the full spatiotemporal patterns of progression. We then used this information
to develop a Markov chain dynamical model of metastatic breast cancer. This is a model based on the concept that where the disease currently is located strongly influences where it will spread next.
The systemic nature of metastatic breast cancer is clearly shown in these kinds of network based models.
The main findings are that survival depends very strongly on where the first metastatic tumor develops. For example, if the first metastatic tumor appears in the bone, as happens in roughly 35% of the patients, survival is much better than if it appears in the brain (less than 5% of the patients). Furthermore, for those patients with a first met to the bone, survival is far better for those who develop their next met in the lung area, as compared with those that develop it in the liver.
Metastatic sites are categorized as `spreader’ sites, or `sponge’ sites. Bone and chest wall are generally the primary spreader sites of metastatic breast cancer, dynamically involved in spreading the disease throughout the metastatic process. On the other hand, liver seems to be a key sponge site, where circulating tumor cells most likely accumulate. If one were to focus on an active therapeutic program targeting metastatic sites, most likely the spreader sites would give the most bang-for-buck in terms of survival.
Prof. Chiang[/caption]
MedicalResearch.com Interview with:
Prof. Bor-Luen Chiang
Vice Superintendent, National Taiwan University Hospital
Professor of Graduate Institute of Clinical Medicine and Pediatrics
National Taiwan University
Attending Physician, Department of Medical research
National Taiwan University Hospital and
Yung-Sen Chang, MD MPH
Attending physician, Department of Pediatrics,
Taipei City Hospital Renai Br.
Adjunct Attending Physician, Department of Pediatrics
National Taiwan University Children’s Hospital
Adjunct Instructor, School of Medicine, National Yang-Ming University
Medical Research: What is the background for this study?
Prof. Chang: Sleep disturbance is a common disorder in the children with atopic dermatitis (AD) (reported in 47 to 60%), but no effective way of managing this problem had been established. In our preceding study, we found that lower nocturnal melatonin level was significantly associated with sleep disturbance in the patients with AD. Melatonin is a hormone secreted by the pineal gland which plays an important role in sleep regulation. In addition to sleep-inducing effects, melatonin also has anti-inflammatory and immunomodulatory properties which might be helpful for the management o fatopic dermatitis. Furthermore, melatonin has an excellent safety profile with minimal adverse effects, making it a good choice for children. Therefore, we aimed to evaluate whether melatonin is effective for improving the sleep problems and the dermatitis severity in children with 
Imre Noth, M.D.[/caption]
MedicalResearch.com Interview with:
Imre Noth, M.D.
Professor of Medicine and Director of the Interstitial Lung Disease Programme
The University of Chicago
Medical Research: What is the background for this study? What are the main findings?
Dr. Noth: In 2014, OFEV® (nintedanib) became one of the first FDA-approved drug treatments for idiopathic pulmonary fibrosis (IPF), a rare and serious lung disease that causes permanent scarring of the lungs. In this post-marketing surveillance study in the United States, treatment with OFEV in the real-world clinical setting showed a safety profile consistent with that observed in clinical trials supporting its approval by the FDA.
Post-marketing surveillance of the safety and tolerability of OFEV in the United States has been collected in the Boehringer Ingelheim drug safety and reporting database since OFEV was first approved on October 15, 2014. Until May 31, 2015, 3,838 people were treated with OFEV for a length of time ranging from 14 to 265 days (on average 88 days). The most frequently reported side effects were gastrointestinal in nature and included diarrhea, nausea, vomiting and decreased appetite. Diarrhea was the most frequently reported individual side effect, occurring at a similar frequency to that observed in the clinical trials supporting approval. No new safety concerns were identified.
Dr. Nesper[/caption]
MedicalResearch.com Interview with:
Arica Nesper, MD, MAS
Resident Physician
Stanford/Kaiser Emergency Medicine Residency
Stanford University Medical Center
Department of Emergency Medicine
Stanford
Medical Research: What is the background for this study? What are the main findings?
Dr. Nesper: Patients with severe mental illness are a distinct demographic in the emergency department. Unfortunately, resources to help these vulnerable patients are frequently the target of funding cuts. We aimed to describe the effect of these cuts on our emergency department and the care provided to our patients. In this study we evaluated data from before our county mental health facility cut its inpatient capacity by half and closed its outpatient unit, and compared this data with data collected after this closure. We found that the mean number of daily psychiatric consultations in our emergency department more than tripled and that the average length of stay for these patients increased by nearly eight hours. These two data combined demonstrate a five-fold increase in daily emergency department bed hours for psychiatric patients, placing a significant strain on the emergency department and demonstrating a delay in definitive care provided to these vulnerable patients.
Dr. Kenworthy[/caption]
MedicalResearch.com Interview with:
Lauren Kenworthy, PhD
Associate professor of Neurology, Pediatrics, and Psychiatry
George Washington University School of Medicine
Director of the Center for Autism Spectrum Disorders
Children’s National Health System
Medical Research: What is the background for this study? What are the main findings?
Dr. Kenworthy: Connectivity among brain regions may account for variability in autism outcomes not explained by age or behavioral measures, according to a study. We have previously shown that behavioral assessments of intelligence, baseline adaptive behavior and executive functions in people with autism can explain some of the variation in outcomes and function, but we have not been able to explain all of the variance in outcome (e.g. Pugliese et al 2015a, 2015b).
In this study, we found that 44% of the study group experienced significant change in scores on adaptive behavior between the initial scan and follow-up. Connectivity between three resting-state networks, including the salience network, the default-mode network, and the frontoparietal task control network, was linked not only to future autistic behaviors but also to changes in autistic and adaptive behaviors over the post-scan period. Further, connectivity involving the salience network and associated brain regions was associated with improvement in adaptive behaviors, with 100% sensitivity and around 71% precision.
Dr. Klebanoff[/caption]
MedicalResearch.com Interview with:
Mark A. Klebanoff, MD
Center for Perinatal Research
The Research Institute
Nationwide Children's Hospital
Medical Research: What is the background for this study? What are the main findings?
Dr. Klebanoff: Caffeine is among the substances most commonly consumed by pregnant women. There are numerous sources of caffeine in the diet—regular (non-decaf) coffee, regular tea, many soft drinks, 
Dr. Raymond Lam[/caption]
MedicalResearch.com Interview with:
Raymond W. Lam, MD, FRCPC
Professor and Associate Head for Research
Department of Psychiatry, University of British Columbia
Director, Mood Disorders Centre, Djavad Mowafaghian Centre for Brain Health
Executive Chair, Canadian Network for Mood and Anxiety Treatments (CANMAT)
Vancouver, BC, Canada
Medical Research: What is the background for this study?
Dr. Lam: Our multicentre team studied the effects of bright light therapy for nonseasonal depression. Light therapy is a non-pharmacological approach that has been studied as a treatment for seasonal affective disorder (SAD, or "winter depression"), but only a small number of studies has explored the use of light therapy in treating nonseasonal depression.
Clinical depression, known formally as Major Depressive Disorder (MDD) is the most common psychiatric disorder and one of the most common medical conditions worldwide. At any given time, at least 1 person in 20 (5% of the general population) is experiencing MDD, which will become the second-leading cause of disability worldwide by 2020, according to the World Health Organization.
Dr. Orian-Rousseau[/caption]
MedicalResearch.com Interview with:
Prof. Dr. Véronique Orian-Rousseau
Group Leader
Karlsruher Institut für Technologie (KIT)
Institut für Toxikologie und Genetik (ITG)
Campus Nord
Karlsruhe Germany
Medical Research: What is the background for this study? What are the main findings?
Response: Our group is working on the role of cell adhesion molecules in development and in tumor progression and metastasis. One protein in focus is CD44, a molecule that controls proliferation, differentiation and survival of cells. We have shown that one member of this family, namely CD44v6 acts as a co-receptor for receptor tyrosine kinases (RTKs) such as MET and VEGFR-2. CD44v6 has a dual function. It controls both the activation and signaling from the RTKs. We have identified a sequence in CD44v6 that is crucial for its function as a co-receptor. From this sequence we made a peptide that inhibits MET and VEGFR2 activation and signaling.
The CD44v6 peptide was used in several independent mouse models of pancreatic cancer including the transgenic PDAC mouse model. It could inhibit the growth of the primary tumor, metastasis and in addition could eliminate already established metastases.
In addition, we could show that MET and CD44v6 expression correlates with poor prognosis and metastasis in a cohort of pancreatic cancer patients.
Dr. González-Pacheco[/caption]
MedicalResearch.com Interview with:
Dr. Héctor González-Pacheco MD
Coronary Care Unit, National Institute of Cardiology
Mexico City, Mexico
Medical Research: What is the background for this study?
Dr. González-Pacheco: Epidemiological studies have provided robust evidence for an inverse correlation between plasma levels of high-density lipoprotein cholesterol (HDL-C) and cardiovascular risk. At hospital admission, a high percentage of patients with an acute coronary syndrome (ACS) have low HDL-C levels. Currently, the association of very low levels of HDL-C with early mortality in patients with ACS is still a topic of considerable interest. However, the possible mechanisms are not clear. Since an acute coronary syndrome induces an inflammatory response, and several chronic systemic diseases and acute critical illnesses with clear pro-inflammatory components have been associated with significantly reduced HDL-C levels, and investigators have shown an inverse correlation between HDL-C levels and the levels of pro-inflammatory cytokines, we hypothesized that reduced HDL-C levels in 
Dr. Yang[/caption]
MedicalResearch.com Interview with:
Quanhe Yang, PhD
Division for Heart Disease and Stroke Prevention
Centers for Disease Control and Prevention
Atlanta, GA 30341
MedicalResearch: What is the background for this study? What are the main findings?
Dr. Yang: Body mass index (BMI) is an important risk factor for high blood pressure among adolescents. Despite a recent leveling off in the numbers of overweight and obese youths, weight-associated health outcomes remain a problem in the U.S. Some researchers have suggested that the increased prevalence of high blood pressure among adolescents is associated with the epidemic of overweight and obesity in the U.S.
As a result, we analyzed trends in pre-high blood pressure and high blood pressure among U.S. youth using data from a series of National Health and Nutrition Examination Surveys. Nearly 15,000 adolescents between the ages of 12 and 19 were included in the surveys, which were conducted between 1988 and 2012.
During that 24-year timeframe, the prevalence of high blood pressure actually decreased overall, while pre-high blood pressure remained largely unchanged. However, those rates differed based on body weight category. For example, pre-high blood pressure was consistently higher among overweight/obese adolescents (18 to 22 percent) than those of normal weight (11 to 12 percent). The observed changes in both pre-high blood pressure and high blood pressure prevalence were consistent across age group, sex and race/ethnicity.
MedicalResearch.com Interview with:
Brittany Kmush, ScM
Doctoral Candidate
Global Disease Epidemiology and Control
Department of International Health
Johns Hopkins Bloomberg School of Public Health
Baltimore, MD
Medical Research: What is the background for this study? What are the main findings?
Response: Hepatitis E virus (HEV) is a global pathogen responsible for approximately 20 million infections every year in developing countries. In the general population, HEV causes acute, self-limiting hepatitis with only a 1-2% case fatality rate. However, in pregnant women, Hepatitis E virus infection can be very severe, resulting in fulminant hepatic failure and death, with a case fatality rate around 30%. Despite this important burden, Hepatitis E virus remains an under-recognized and under-reported pathogen. The early years of HEV research were plagued by poor quality commercial assays, highly variable in sensitivity and specificity. As a result, there is still no diagnostic assay approved for commercial use in the United States. However, over the past two decades, several new, highly sensitive and specific assays have been developed.
In this study, we re-tested banked sera from a population-based sero-survey of over 1000 participants from rural Bangladesh in order to investigate the comparability of a high-performing first generation test to recently developed, commercially available assay. In the early 2000s, the Walter Reed Army Institute of Research (WRAIR, Bethesda, MD) developed an in-house enzyme immune-assay (EIA) to diagnose Hepatitis E virus infections by detecting anti-HEV total immunoglobulin (Ig) in serum. More recently, Wantai Diagnostics (Beijing, China) developed a commercially available EIA for detecting anti-HEV IgG.
The WRAIR assay estimated the overall population seroprevalence as 26.6% while the Wantai assay produced significantly higher estimated seroprevalence, 46.7%. There was a 77% agreement between the two tests. Overall, the Wantai assay found a much higher seroprevalence of anti-HEV antibodies compared to the WRAIR assay, using the same serum. Additionally, the majority of the differences between the two tests are from people initially classified by WRAIR as anti-HEV negative that Wantai classified as anti-HEV positive.
Dr. Oktay[/caption]
MedicalResearch.com Interview with:
Kutluk Oktay, MD, PhD.
Professor of Obstetrics & Gynecology, Medicine, and Cell Biology & Anatomy
Director, Division of Reproductive Medicine & Institute for Fertility Preservation
Innovation Institute for Fertility and In Vitro Fertilization
New York Medical College, Valhalla, NY
Medical Research: What is the background for this study? What are the main findings?
Dr. Oktay: Cancer treatments cause infertility and early menopause in a growing number of young women around the world and US. One of the strategies to preserve fertility, which was developed by our team, is to cryopreserve ovarian tissue before chemotherapy and later transplant it back to the patient when they are cured of the cancer and ready to have children. However, success of ovarian transplantation has been limited due to limitation in blood flow to grafts. In this study we described a new approach which seems to improve graft function. The utility of an extracellular tissue matrix and robotic surgery seems to enhance graft function. With this approach both patients conceived with frozen embryos to spare and one has already delivered.
Dr. Jerome Leis[/caption]
MedicalResearch.com Interview with:
Jerome A. Leis, MD MSc FRCPC
Staff physician, General Internal Medicine and Infectious Diseases
Physician Lead, Antimicrobial Stewardship Team
Staff member, Centre for Quality Improvement and Patient Safety
Sunnybrook Health Sciences Centre
Assistant Professor, Department of Medicine, University of Toronto
Medical Research: What is the background for this study? What are the main findings?
Dr. Leis: Overuse of urinary catheters leads to significant morbidity among hospitalized patients. In most hospitals, discontinuation of urinary catheters relies on individual providers remembering to re-assess whether patients have an ongoing reason for a urinary catheter. We engaged all of the attending physicians to agree on the appropriate reasons for leaving a urinary catheter in place and developed a medical directive for nurses to remove all urinary catheters lacking these indications. This nurse-led intervention resulted in a significant reduction in urinary catheter use and catheter-associated urinary tract infections, compared with wards that continued to rely on usual practice.
Dr. Jason Gold[/caption]
MedicalResearch.com Interview with:
Jason S. Gold MD FACS
Chief of Surgical Oncology, VA Boston Healthcare System
Assistant Professor of Surgery, Harvard Medical School
Brigham and Women’s Hospital
Medical Research: What is the background for this study?
Dr. Gold: Pancreas cancer is a lethal disease. While advances in the best available care for pancreas cancer are desperately needed, improvements can be made in addressing disparities in care. This study aimed to evaluate associations of social and demographic variables with the utilization of surgical resection as well as with survival after surgical resection for early-stage pancreas cancer.
Medical Research: What are the main findings?
Dr. Gold: The main findings are the following:
1: We found that less than half of patients with early-stage pancreas cancer undergo resection in the United States. Interestingly, the rate of resection has not changed with time during the eight-year study period.
2. We also found significant disparities associated with the utilization of surgical resection for early-stage pancreas cancer in the United States. African American patients, Hispanic patients, single patients, and uninsured patients were significantly less likely to have their tumors removed. There were regional variations in the utilization of surgical resection as well. Patients in the Southeast were significantly less likely to have a pancreas resection for cancer compared to patients in the Northeast.
3. Among the patients who underwent surgical resection for early-stage pancreas cancer, we did not see significant independent associations with survival for most of the social and demographic variables analyzed. Surprisingly, however, patients from the Southeast had worse long-term survival after pancreas cancer resection compared to those in other regions of the United States even after adjusting for other variables.
Prof. Bisgaard[/caption]
MedicalResearch.com Interview with:
Professor of Pediatrics Hans Bisgaard, MD, DMSc
Copenhagen Prospective Studies on Asthma in Childhood
Herlev and Gentofte Hospital,
University of Copenhagen, Denmark
Medical Research: What is the background for this study?
Prof. Bisgaard: Birth season has been reported to be a risk factor for several immune-mediated diseases, although the critical season varies depending on the disease. Autoimmune diseases are generally associated with spring births, whereas asthma and allergies are more common among subjects born in fall and winter. Because many of these diseases, such as asthma, rheumatoid arthritis, and 
MedicalResearch.com Interview with:
Claudia van Borkulo, MSc
University of Groningen, University Medical Center Groningen
Department of Psychiatry,
Research School of Behavioural and Cognitive Neurosciences,
Interdisciplinary Center for Psychopathology and Emotion Regulation,
Groningen, the Netherlands
Medical Research: What is the background for this study? What are the main findings?
Response: We consider psychiatric disorders as complex dynamical systems in which symptoms can interact with each other. This novel network approach to psychopathology – that is new to psychiatry – implies that a more densely connected network of symptoms of a disorder might be indicative of worse prognosis. Having one symptom can easily lead to developing more symptoms in a densely connected network, in which more symptoms reinforce each other. Reversely, a symptom in a less densely connected network will rarely turn on other symptoms. A densely connected network can theoretically be related to an increased vulnerability; because of the high level of mutual reinforcement, a small external stressor can induce a quicker transition from a healthy state to a depressed state for people with a more densely connected network.
In our study, we investigated the association between baseline network structure of