Is Surgery a Risk Factor for Creutzfeldt-Jakob Disease? Outcome Variation by Control Choice and Exposure Assessments

2008 ◽  
Vol 29 (3) ◽  
pp. 212-218 ◽  
Author(s):  
Jed A. Barash ◽  
Blair T. Johnson ◽  
David I. Gregorio
Keyword(s):  
Risk Factor ◽  
Positive Association ◽  
Case Control ◽  
Effect Sizes ◽  
Sources Of Information ◽  
Case Control Studies ◽  
Significant Positive Association ◽  
Design Elements ◽  
Control Subjects ◽  
Jakob Disease

Objective.To determine whether methodological differences explain divergent results in case-control studies examining surgery as a risk factor for Creutzfeldt-Jakob disease (CJD).Methods.After case-control studies were systematically identified using PubMed, we performed a homogeneity analysis and applied models to effect sizes (odds ratio [OR] with 95% confidence interval [CI]) using 2 parameters: type of control subject used and consistency of data ascertainment. The hospitals and communities were located in Europe, Japan, and Australia. Patients were CJD case subjects and age- and sex-matched control subjects in the hospital or community. Because of the natural history of the disease, CJD subjects are not considered reliable sources of information for these studies. Therefore, individuals who are considered close to the subjects and who have knowledge of their medical history, including spouses and relatives, are necessarily identified as proxy informants for the surgical record of the case subjects.Results.Overall, the effect sizes lacked homogeneity (P<.0001). Three studies that used control subjects from the community revealed a significantly elevated risk of CJD for patients who underwent surgery (OR, 1.82; 95% CI, 1.41-2.35 [P<.0001 ]), whereas 3 investigations that used control subjects from the hospital revealed a significantly reduced risk (OR, 0.69; 95% CI, 0.52-0.90 [P = .0069]). Two studies that used proxy informants to acquire information about case subjects and control subjects (consistent ascertainment) found that the risk of CJD was significantly lower in those subjects who underwent surgery (OR, 0.65; 95% CI, 0.48-0.87 [P = .0043]). Conversely, 4 studies in which proxy informants acted only on behalf of case subjects (inconsistent data ascertainment) found a significant positive association between surgery and CJD (OR, 1.67; 95% CI, 1.32-2.12 [P<.0001 ]). Both models fit the data very well, leaving no remaining variance in effect sizes to explain.Conclusion.Variation in the type of control subjects used and in exposure assessment in case-control studies may partially explain conflicting data regarding the association between surgery and CJD. However, there was almost complete confounding of these 2 parameters, making interpretation more difficult. Planning of future investigations must carefully consider these design elements.

scholarly journals Cellular Phone Use and Risk of Tumors: Systematic Review and Meta-Analysis

2020 ◽  
Vol 17 (21) ◽  
pp. 8079
Author(s):  
Yoon-Jung Choi ◽  
Joel M. Moskowitz ◽  
Seung-Kwon Myung ◽  
Yi-Ryoung Lee ◽  
Yun-Chul Hong
Keyword(s):  
Meta Analysis ◽  
Harmful Effect ◽  
Positive Association ◽  
Cellular Phone ◽  
Case Control ◽  
International Agency ◽  
Case Control Studies ◽  
Significant Positive Association ◽  
Tumor Risk ◽  
Increased Risk

We investigated whether cellular phone use was associated with increased risk of tumors using a meta-analysis of case-control studies. PubMed and EMBASE were searched from inception to July 2018. The primary outcome was the risk of tumors by cellular phone use, which was measured by pooling each odds ratio (OR) and its 95% confidence interval (CI). In a meta-analysis of 46 case-control studies, compared with never or rarely having used a cellular phone, regular use was not associated with tumor risk in the random-effects meta-analysis. However, in the subgroup meta-analysis by research group, there was a statistically significant positive association (harmful effect) in the Hardell et al. studies (OR, 1.15—95% CI, 1.00 to 1.33— n = 10), a statistically significant negative association (beneficial effect) in the INTERPHONE-related studies (case-control studies from 13 countries coordinated by the International Agency for Research on Cancer (IARC); (OR, 0.81—95% CI, 0.75 to 0.89—n = 9), and no statistically significant association in other research groups’ studies. Further, cellular phone use with cumulative call time more than 1000 h statistically significantly increased the risk of tumors. This comprehensive meta-analysis of case-control studies found evidence that linked cellular phone use to increased tumor risk.

scholarly journals Morning plasma cortisol as a cardiovascular risk factor: findings from prospective cohort and Mendelian randomization studies

2019 ◽  
Vol 181 (4) ◽  
pp. 429-438 ◽  
Author(s):  
Andrew A Crawford ◽  
Stefan Soderberg ◽  
Clemens Kirschbaum ◽  
Lee Murphy ◽  
Mats Eliasson ◽  
...  
Keyword(s):  
Risk Factor ◽  
Plasma Cortisol ◽  
Mendelian Randomization ◽  
Meta Analysis ◽  
Positive Association ◽  
Case Control ◽  
Case Control Studies ◽  
Cvd Risk ◽  
Causal Risk Factor ◽  
Nested Case Control

Objective The identification of new causal risk factors has the potential to improve cardiovascular disease (CVD) risk prediction and the development of new treatments to reduce CVD deaths. In the general population, we sought to determine whether cortisol is a causal risk factor for CVD and coronary heart disease (CHD). Design and methods Three approaches were adopted to investigate the association between cortisol and CVD/CHD. First, we used multivariable regression in two prospective nested case-control studies (total 798 participants, 313 incident CVD/CHD with complete data). Second, a random-effects meta-analysis of these data and previously published prospective associations was performed (total 6680 controls, 696 incident CVD/CHD). Finally, one- and two-sample Mendelian randomization analyses were performed (122,737 CHD cases, 547,261 controls for two-sample analyses). Results In the two prospective nested case–control studies, logistic regression adjusting for sex, age, BMI, smoking and time of sampling, demonstrated a positive association between morning plasma cortisol and incident CVD (OR: 1.28 per 1 SD higher cortisol, 95% CI: 1.06–1.54). In the meta-analysis of prospective studies, the equivalent result was OR: 1.18, 95% CI: 1.06–1.31. Results from the two-sample Mendelian randomization were consistent with these positive associations: OR: 1.06, 95% CI: 0.98–1.15. Conclusions All three approaches demonstrated a positive association between morning plasma cortisol and incident CVD. Together, these findings suggest that elevated morning cortisol is a causal risk factor for CVD. The current data suggest strategies targeted at lowering cortisol action should be evaluated for their effects on CVD.

scholarly journals Running and Knee Osteoarthritis: A Systematic Review and Meta-analysis

2016 ◽  
Vol 45 (6) ◽  
pp. 1447-1457 ◽  
Author(s):  
Kate A. Timmins ◽  
Richard D. Leech ◽  
Mark E. Batt ◽  
Kimberley L. Edwards
Keyword(s):  
Systematic Review ◽  
Full Text ◽  
Meta Analysis ◽  
Positive Association ◽  
Case Control ◽  
Case Control Studies ◽  
Eligibility Criteria ◽  
Knee Oa ◽  
Knee Joint Surgery ◽  
Newcastle Ottawa Scale

Background: Osteoarthritis (OA) is a chronic condition characterized by pain, impaired function, and reduced quality of life. A number of risk factors for knee OA have been identified, such as obesity, occupation, and injury. The association between knee OA and physical activity or particular sports such as running is less clear. Previous reviews, and the evidence that informs them, present contradictory or inconclusive findings. Purpose: This systematic review aimed to determine the association between running and the development of knee OA. Study Design: Systematic review and meta-analysis. Methods: Four electronic databases were searched, along with citations in eligible articles and reviews and the contents of recent journal issues. Two reviewers independently screened the titles and abstracts using prespecified eligibility criteria. Full-text articles were also independently assessed for eligibility. Eligible studies were those in which running or running-related sports (eg, triathlon or orienteering) were assessed as a risk factor for the onset or progression of knee OA in adults. Relevant outcomes included (1) diagnosis of knee OA, (2) radiographic markers of knee OA, (3) knee joint surgery for OA, (4) knee pain, and (5) knee-associated disability. Risk of bias was judged by use of the Newcastle-Ottawa scale. A random-effects meta-analysis was performed with case-control studies investigating arthroplasty. Results: After de-duplication, the search returned 1322 records. Of these, 153 full-text articles were assessed; 25 were eligible, describing 15 studies: 11 cohort (6 retrospective) and 4 case-control studies. Findings of studies with a diagnostic OA outcome were mixed. Some radiographic differences were observed in runners, but only at baseline within some subgroups. Meta-analysis suggested a protective effect of running against surgery due to OA: pooled odds ratio 0.46 (95% CI, 0.30-0.71). The I2 was 0% (95% CI, 0%-73%). Evidence relating to symptomatic outcomes was sparse and inconclusive. Conclusion: With this evidence, it is not possible to determine the role of running in knee OA. Moderate- to low-quality evidence suggests no association with OA diagnosis, a positive association with OA diagnosis, and a negative association with knee OA surgery. Conflicting results may reflect methodological heterogeneity. More evidence from well-designed, prospective studies is needed to clarify the contradictions.

scholarly journals Sensitivity to Biases of Case-Control Studies on Medical Procedures, Particularly Surgery and Blood Transfusion, and Risk of Creutzfeldt-Jakob Disease

2012 ◽  
Vol 39 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Jesús de Pedro Cuesta ◽  
María Ruiz Tovar ◽  
Hester Ward ◽  
Miguel Calero ◽  
Andrew Smith ◽  
...  
Keyword(s):  
Blood Transfusion ◽  
Case Control ◽  
Medical Procedures ◽  
Case Control Studies ◽  
Jakob Disease

scholarly journals Dissecting autism and schizophrenia through neuroimaging genomics

Brain ◽  
2021 ◽  
Author(s):  
Clara A Moreau ◽  
Armin Raznahan ◽  
Pierre Bellec ◽  
Mallar Chakravarty ◽  
Paul M Thompson ◽  
...  
Keyword(s):  
High Risk ◽  
Psychiatric Symptoms ◽  
Clinical Manifestations ◽  
Autism Spectrum ◽  
Case Control ◽  
Effect Sizes ◽  
Case Control Studies ◽  
Top Down ◽  
Bottom Up ◽  
Genomic Variants

Abstract Neuroimaging genomic studies of autism spectrum disorder and schizophrenia have mainly adopted a ‘top-down’ approach, starting with the behavioural diagnosis, and moving down to intermediate brain phenotypes and underlying genetic factors. Advances in imaging and genomics have been successfully applied to increasingly large case-control studies. As opposed to diagnostic-first approaches, the bottom-up strategy starts at the level of molecular factors enabling the study of mechanisms related to biological risk, irrespective of diagnoses or clinical manifestations. The latter strategy has emerged from questions raised by top-down studies: Why are mutations and brain phenotypes over-represented in individuals with a psychiatric diagnosis? Are they related to core symptoms of the disease or to comorbidities? Why are mutations and brain phenotypes associated with several psychiatric diagnoses? Do they impact a single dimension contributing to all diagnoses? In the review, we aimed at summarizing imaging genomic findings in autism and schizophrenia as well as neuropsychiatric variants associated with these conditions. Top-down studies of autism and schizophrenia identified patterns of neuroimaging alterations with small effect-sizes and an extreme polygenic architecture. Genomic variants and neuroimaging patterns are shared across diagnostic categories suggesting pleiotropic mechanisms at the molecular and brain network levels. Although the field is gaining traction; characterizing increasingly reproducible results, it is unlikely that top-down approaches alone will be able to disentangle mechanisms involved in autism or schizophrenia. In stark contrast with top-down approaches, bottom-up studies showed that the effect-sizes of high-risk neuropsychiatric mutations are equally large for neuroimaging and behavioural traits. Low specificity has been perplexing with studies showing that broad classes of genomic variants affect a similar range of behavioral and cognitive dimensions, which may be consistent with the highly polygenic architecture of psychiatric conditions. The surprisingly discordant effect sizes observed between genetic and diagnostic first approaches underscore the necessity to decompose the heterogeneity hindering case-control studies in idiopathic conditions. We propose a systematic investigation across a broad spectrum of neuropsychiatric variants to identify putative latent dimensions underlying idiopathic conditions. Gene expression data on temporal, spatial and cell type organization in the brain have also considerable potential for parsing the mechanisms contributing to these dimensions phenotypes. While large neuroimaging genomic datasets are now available in unselected populations, there is an urgent need for data on individuals with a range of psychiatric symptoms and high-risk genomic variants. Such efforts together with more standardized methods will improve mechanistically informed predictive modeling for diagnosis and clinical outcomes.

scholarly journals Surgery and Risk of Sporadic Creutzfeldt-Jakob Disease in Denmark and Sweden: Registry-Based Case-Control Studies

2008 ◽  
Vol 31 (4) ◽  
pp. 229-240 ◽  
Author(s):  
Ignacio Mahillo-Fernandez ◽  
Jes&uacute;s de Pedro-Cuesta ◽  
Maria Jos&eacute; Bleda ◽  
Mabel Cruz ◽  
K&aring;re M&oslash;lbak ◽  
...  
Keyword(s):  
Case Control ◽  
Case Control Studies ◽  
Jakob Disease

scholarly journals Psychological Autopsy Studies of Suicide in South East Asia

2021 ◽  
pp. 025371762110336
Author(s):  
S.M. Yasir Arafat ◽  
Vikas Menon ◽  
Natarajan Varadharajan ◽  
Sujita Kumar Kar
Keyword(s):  
Risk Factors ◽  
Risk Factor ◽  
East Asia ◽  
Psychiatric Disorders ◽  
Study Design ◽  
Case Control ◽  
Stressful Life ◽  
South East Asia ◽  
Psychological Autopsy ◽  
Case Control Studies

Background: Psychiatric disorders have been identified as an important risk factor for suicide. However, different psychological autopsy studies have revealed different prevalences at different times and places. Objective: We aimed to see the distribution of psychological autopsy studies and the prevalence of mental disorders among suicides and identify major risk factors in Southeast Asian countries. Method: We scrutinized psychological autopsy studies published in the World Health Organization (WHO) South-East Asia (SEA) region countries. We also searched the available bibliographies to identify the studies in the region so that all the possible articles could be included. Results: Out of the 11 countries, 14 psychological autopsy studies were identified in five SEA countries (Bangladesh [1], India [9], Indonesia [1], Nepal [1], and Sri Lanka [2]). Seven studies (50%) used a case-control study design, and eight (57.1%) were carried out in urban settings. The prevalence of psychiatric disorders in case-control studies was from 37% to 88%. Stressful life event was identified as a major risk factor in all the case-control studies. Conclusion: Psychological autopsy studies have not been conducted in 6 out of 11 countries of the SEA region. The presence of pre-existing psychiatric morbidity and stressful life events were the two most common risk factors noted across settings, even though there is wide heterogeneity in samples, study design, instruments, and study settings.

Vitamin D deficiency as a risk factor for thyroid cancer: A meta-analysis of case-control studies

Nutrition ◽  
2019 ◽  
Vol 57 ◽  
pp. 5-11 ◽  
Author(s):  
Junyu Zhao ◽  
Haipeng Wang ◽  
Zhongwen Zhang ◽  
Xiaojun Zhou ◽  
Jinming Yao ◽  
...  
Keyword(s):  
Vitamin D ◽  
Risk Factor ◽  
Thyroid Cancer ◽  
Vitamin D Deficiency ◽  
Meta Analysis ◽  
Case Control ◽  
Case Control Studies

Response rates among control subjects in case-control studies☆

1995 ◽  
Vol 5 (3) ◽  
pp. 245-249 ◽  
Author(s):  
Martha L. Slattery ◽  
Sandra L. Edwards ◽  
Bette J. Caan ◽  
Richard A. Kerber ◽  
John D. Potter
Keyword(s):  
Response Rates ◽  
Case Control ◽  
Case Control Studies ◽  
Control Subjects

scholarly journals Is Opium a Real Risk Factor for Esophageal Cancer or Just a Methodological Artifact? Hospital and Neighborhood Controls in Case-Control Studies

PLoS ONE ◽  
2012 ◽  
Vol 7 (3) ◽  
pp. e32711 ◽  
Author(s):  
Ramin Shakeri ◽  
Farin Kamangar ◽  
Dariush Nasrollahzadeh ◽  
Mehdi Nouraie ◽  
Hooman Khademi ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Risk Factor ◽  
Case Control ◽  
Case Control Studies ◽  
Real Risk ◽  
Methodological Artifact
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