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European Journal of Epidemiology Apr 2012Increased body mass index (BMI) is a worldwide health issue. Individual differences in the susceptibility to increased BMI could be related to genes or environment. We... (Review)
Review
Increased body mass index (BMI) is a worldwide health issue. Individual differences in the susceptibility to increased BMI could be related to genes or environment. We performed a systematic review of genetic studies on BMI in pre-adolescence, young adulthood and late adulthood. We searched PubMed and EMBASE with heritability, body mass index, BMI, weight, height, anthropometry and twins as search terms. Studies reporting intra-pair correlations of healthy twin pairs that were raised together were included. This resulted in the inclusion of 8,179 monozygotic (MZ) and 9,977 dizygotic (DZ) twin pairs from twelve published studies in addition to individual participant data for 629 MZ and 594 DZ pairs from four twin registries. Structural equation modelling with intra-pair twin correlations showed that the heritability of BMI remained high over all age categories ranging from 61% (95% CI 54-64%) to 80% (95% CI 76-81%) for male and female subjects combined, while unique environmental influences increased from 14% (95% CI 13-15%) to 40% (95% CI 37-43%) with increasing age. Heritability of BMI remains consistently high over different age categories. Environmental changes over time do not seem to have as big a relative impact on an individual's weight as previously reported, suggesting a mainly genetic influence on variation in BMI over the years.
Topics: Body Composition; Body Mass Index; Body Weight; Child; Female; Humans; Male; Middle Aged; Obesity; Registries; Twins; Young Adult
PubMed: 22426805
DOI: 10.1007/s10654-012-9678-6 -
Cornea Dec 2022The objective of this study was to undertake a systematic review of the literature reporting on clinical registries in dry eye disease (DED).
PURPOSE
The objective of this study was to undertake a systematic review of the literature reporting on clinical registries in dry eye disease (DED).
METHODS
Electronic searches were conducted using systematic review methodology to provide an overview of clinical registries in ophthalmology and to identify clinical registries reporting on dry eye parameters. Two reviewers independently assessed titles and abstracts, then full-texts for eligibility.
RESULTS
A total of 129 clinical registries in ophthalmology were identified. The most common conditions captured were blindness or low vision, followed by glaucoma and corneal transplantation. Most of the registries originated in Europe (n = 56), followed by North America (n = 28). Of the registries identified, 12 were multinational, 59 were national, and 17 were regional. The second search identified 27 eligible articles, from which 8 clinical registries reporting on dry eye parameters were identified. One registry included patients with a diagnosis of dry eye. The remaining 7 registries included patients from a nationwide administrative ophthalmic database (n = 1), Sjögren syndrome (n = 4), glaucoma (n = 1), or were monozygotic and dizygotic twins (n = 1), who were evaluated for DED. Five of the registries were actively collecting data.
CONCLUSIONS
Most of the registries identified in this review evaluated aqueous deficient dry eye; however, the most common type of dry eye in the general population is evaporative. Few registries also collected recommended dry eye clinical assessment. A well-designed clinical registry for DED that engages international eye care clinicians has the potential to vastly contribute to addressing pivotal gaps in understanding this highly prevalent disease.
Topics: Humans; Dry Eye Syndromes; Registries; Ophthalmology; Databases, Factual; Glaucoma
PubMed: 36197325
DOI: 10.1097/ICO.0000000000003139 -
American Journal of Medical Genetics.... Mar 2019Twins, particularly monochorionic (MC) pairs, are at increased risk for fetal death. Whereas previous work has sought to understand the mechanisms for this increased...
Twins, particularly monochorionic (MC) pairs, are at increased risk for fetal death. Whereas previous work has sought to understand the mechanisms for this increased mortality, most studies analyze viable twin pregnancies or liveborn twin cohorts. In the Wisconsin Stillbirth Service Program cohort of 3,137 stillbirths and second trimester miscarriages, we identified 175 twin pregnancies for a twinning rate of 56/1,000, which is approximately double the general population. The excess of twins among miscarriages and stillbirths was attributable to MC pairs as the incidence of dizygotic (DZ) twinning was not increased compared to livebirth data. The leading causes of fetal demise among twins were twin-twin transfusion, acardia, and twin-twin disruption. Maternal causes of death, primarily premature rupture of membranes, were moderately increased in both MC and DZ twins relative to singletons. Although deceased twins were smaller than expected for viable twins at comparable gestational ages, placenta weights of deceased MC pairs were large compared to combined fetal weight, which indicates placental inefficiency likely due to vascular shunting. Co-twin survival was much lower for MC than for DZ pairs. Therefore, earlier diagnosis and treatment of MC twinning complications may decrease prenatal mortality.
Topics: Abortion, Spontaneous; Cause of Death; Databases, Factual; Female; Fetal Death; Health Surveys; Humans; Pregnancy; Pregnancy Trimester, Second; Pregnancy, Twin; Prevalence; Stillbirth; Twins, Dizygotic; Twins, Monozygotic; Wisconsin
PubMed: 30663217
DOI: 10.1002/ajmg.a.61014 -
Medicine Jun 2020Published findings on perinatal outcomes of multifetal pregnancy reduction (MPR) of dichorionic diamniotic (DCDA) twin pregnancy to singleton are controversial. We... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Published findings on perinatal outcomes of multifetal pregnancy reduction (MPR) of dichorionic diamniotic (DCDA) twin pregnancy to singleton are controversial. We performed a meta-analysis to appraise the effects of MPR of DCDA twin pregnancy versus expectant management on perinatal outcomes.
METHODS
Four electronic databases were searched from their inception to June 15, 2019, to identify publications that appraised MPR before 15 weeks of gestation. Studies reporting perinatal outcomes of both MPR of DCDA twin pregnancy to singleton and expectant management were considered. The relative risks (RRs) and mean differences with 95% confidence intervals (CIs) were pooled using a random-effects model.
RESULTS
Six studies involving 7398 participants showed that MPR of DCDA twin pregnancy to singleton was associated with a lower risk of preterm birth (5 studies with 7297 participants; RR: 0.30, 95% CI: 0.22-0.40; P < .001) and higher birth weight (4 studies with 5763 participants; mean differences: 548.10 g, 95% CI: 424.04-672.15; P < .001) than expectant management; there was no difference in the occurrence of miscarriages (5 studies with 7355 participants; RR: 1.57, 95% CI: 0.90-2.75; P = .11). Sensitivity analysis showed that all the results were stable and reliable, with the omission of 2 studies with serious risk of bias.
CONCLUSION
Compared to expectant management, MPR of DCDA twin pregnancy to singleton prevents preterm birth and low birth weight, without increasing the risk of miscarriages. Regarding perinatal morbidity related to preterm birth, MPR can be reserved as a remediation measure to improve the perinatal outcomes of DCDA twin pregnancies.
Topics: Adult; Amnion; Chorion; Female; Humans; Pregnancy; Pregnancy Outcome; Pregnancy Reduction, Multifetal; Pregnancy, Twin; Twinning, Dizygotic; Twins, Dizygotic; Watchful Waiting
PubMed: 32569212
DOI: 10.1097/MD.0000000000020730 -
Twin Research and Human Genetics : the... Feb 2012Cervical cancer is the third most common cancer in women worldwide. Persistent infection with an oncogenic human papillomavirus (HPV) is necessary, but not sufficient,... (Meta-Analysis)
Meta-Analysis
Cervical cancer is the third most common cancer in women worldwide. Persistent infection with an oncogenic human papillomavirus (HPV) is necessary, but not sufficient, for its development. Over many years, only a small proportion of women with chronic HPV infection progress to develop disease. The role of host genes and environmental factors in the pathogenesis of, or predisposition to, cervical cancer is still unclear. We conducted a systematic review of published literature in MEDLINE-PubMed to identify studies of cervical cancer susceptibility that used a twin study design. We used standard MeSH terms (controlled vocabulary) as well as specific free-text terms and combinations of terms related to cervical cancer, with no restriction on publication date. We performed a full text review to ensure the identified articles met our inclusion criteria and, if so, extracted information on demographics, sample size, study definitions, and key statistical findings. Of the 285 articles identified, three utilized a classical twin design and reported results specific to cervical cancer. The studies were based on cancer registry data from Scandinavia, with sample sizes ranging from 312 to 710 twin pairs. The findings from one study were consistent with a genetic mechanism for the causation of carcinoma in situ. Future research studies using the strength of the classic twin design, together with incorporation of HPV DNA status, are indicated to determine whether there is a potential role for genetic factors in the development of cervical cancer or high-grade cervical dysplasia from chronic oncogenic HPV infection.
Topics: Environment; Female; Humans; Medical Subject Headings; Papillomaviridae; Papillomavirus Infections; PubMed; Risk Factors; Scandinavian and Nordic Countries; Twins, Dizygotic; Twins, Monozygotic; United States; Uterine Cervical Neoplasms
PubMed: 22784457
DOI: 10.1375/twin.15.1.79