Study objective: To determine the relative importance of genetic and environmental contributions to the association between sleep duration and body mass index (BMI). Methods: Twins from the University of Washington Twin Registry, a community-based sample of U.S. twins, provided self-reported height and weight for BMI calculation and habitual sleep duration. A generalized estimating equation model evaluated the […]
Objective: We examined the relative contributions of genetic and environmental influences to restrained eating. Method: Restrained eating was assessed by the Restraint Scale in a survey mailed to all twins enrolled in the University of Washington Twin Registry. We used structural equation modeling to estimate genetic and nongenetic contributions to restrained eating. Results: 1,196 monozygotic (MZ), 456 same-sex […]
Objective: To determine if shared genetic or environmental vulnerabilities could underlie depression and migraine. Background: Depression and migraine headaches frequently coexist and their comorbidity may be due to shared etiologies. Methods: Female twins in the University of Washington Twin Registry responded to a mailed survey regarding their health history. Depression and migraine were determined by self-report of a […]
Aims: To determine whether symptoms of post-traumatic stress disorder (PTSD) are related to the pain of temporomandibular disorders (TMD) in a community-based sample of female twin pairs, and if so, to ascertain whether the association is due to the presence of chronic widespread pain (CWP) and familial/genetic factors. Methods: Data were obtained from 630 monozygotic and 239 […]
Background: The health benefits of regular physical activity are well established. However, the relative contribution of heritable and environmental factors to physical activity participation remains controversial. Using a cut-point of 60 minutes of total activity per week, data from the GenomEUtwin project revealed consistent genetic influence on physical activity participation in 37,051 twin pairs from seven […]
Prolonged fatigue of ≥1 month duration and chronic fatigue of ≥6 months duration are both commonly seen in clinical practice, yet little is known about the etiology or epidemiology of either symptom. Chronic fatigue syndrome (CFS), while rarer, presents similar challenges in determining cause and epidemiology. Twin studies can be useful in elucidating genetic and […]
Background: Considerable overlap in symptoms and disease comorbidity has been noted among medically unexplained and psychiatric conditions seen in the primary care setting, such as chronic fatigue syndrome, low back pain, irritable bowel syndrome, chronic tension headache, fibromyalgia, temporomandibular joint disorder, major depression, panic attacks, and posttraumatic stress disorder. Objective: To examine interrelationships among these 9 conditions. […]
The University of Washington Twin Registry is a community-based registry of twins identified from the Washington State Department of Licensing. A fortuitous quirk in the Washington State drivers’ license and identification number assignment, and collaborative Washington State laws, permitted us to build a statewide registry. Since obtaining approval from the Washington State Attorney General, the […]
Previous studies of the association between posttraumatic stress disorder (PTSD) and chronic widespread pain (CWP) or fibromyalgia have not examined the role of familial or genetic factors. The goals of this study were to determine if symptoms of PTSD are related to CWP in a genetically informative community-based sample of twin pairs, and if so, […]
Objective: The objective of this study was to identify genetic, familial and environmental contributions to the association between posttraumatic stress disorder (PTSD) symptoms and poor health. Methods: A community sample of 1852 twin pairs was assessed for symptoms of PTSD [with the Impact of Events Scale (IES)] and self-reported global health status using a single five-level question. […]
Study objectives: To better understand the relationships of insomnia, sleepiness, and obesity. Design: Classic twin study. Setting: A community-based twin registry in Washington State. Patients or participants: One thousand forty-two monozygotic and 828 dizygotic twin pairs participating in the University of Washington Twin Registry. Interventions: N/A. Measurements and results: Twins were, on average, 32 years old; 61% were women, and 19.5% […]
Background: Asthma and obesity are common conditions that are strongly associated. This association might be due to shared genetic or environmental causes. Objective: We sought to determine whether a shared genetic cause is responsible for the association between asthma and obesity and to estimate the magnitude of shared genetic cause. Methods: The analyses were performed with 1001 monozygotic […]
