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Causal Association (causal + association)
Selected AbstractsThe association of diet and other lifestyle factors with overactive bladder and stress incontinence: a longitudinal study in womenBJU INTERNATIONAL, Issue 1 2003H.M. Dallosso OBJECTIVES To investigate the role of diet and other lifestyle factors in the incidence of overactive bladder and stress incontinence in women. Studies have suggested relationships between different aspects of lifestyle and symptoms of urinary incontinence, but there is a lack of firm evidence about their role in its cause. SUBJECTS AND METHODS A random sample of women aged , 40 years living at home took part in a prospective cohort study. Baseline data on urinary symptoms, diet and lifestyle were collected from 7046 women using a postal survey and food-frequency questionnaire. Follow-up data on urinary symptoms were collected from 6424 of the women in a postal survey 1 year later. Logistic regression was used to investigate the association of food and drink consumption and other lifestyle factors with the incidence of overactive bladder and stress incontinence. RESULTS In the multivariate model for the onset of an overactive bladder, there were significantly increased risks associated with obesity, smoking and consumption of carbonated drinks, and reduced risks with higher consumption of vegetables, bread and chicken. Obesity and carbonated drinks were also significant risk factors for the onset of stress incontinence, while consumption of bread was associated with a reduced risk. CONCLUSIONS Causal associations with obesity, smoking and carbonated drinks are confirmed for bladder disorders associated with incontinence, and additional associations with diet are suggested. Behavioural modification of lifestyle may be important for preventing and treating these disorders. [source] Does gastroesophageal reflux contribute to the development of chronic sinusitis?DISEASES OF THE ESOPHAGUS, Issue 6 2006A review of the evidence SUMMARY., Although recent studies suggest that gastroesophageal reflux disease (GERD) may contribute to a variety of ear, nose and throat and pulmonary diseases, the cause-and-effect relationship for the vast majority remains far from proven. In this article, the evidence supporting a possible causal association between GERD and chronic sinusitis has been reviewed. The evidence would suggest that: (i) a higher prevalence of GERD and a different esophagopharyngeal distribution of the gastric refluxate occurs in patients with chronic sinusitis unresponsive to conventional medical and surgical therapy compared to the general population; (ii) a biologically plausible pathogenetic mechanism exists whereby GERD may result in chronic sinusitis; and (iii) clinical manifestations of chronic sinusitis respond variably to antireflux therapy. While these findings suggest that GERD may contribute to the pathogenesis of chronic sinusitis in some patients, it is apparent that the quality of the evidence supporting each of these three lines of evidence is low and therefore does not conclusively establish a cause-and-effect relationship. A number of unresolved issues regarding prevalence, pathophysiological mechanism, diagnosis and treatment exist that deserve further investigation in order to solidify the relationship between GERD and chronic sinusitis. In conclusion, given the possible relationship between GERD and chronic sinusitis, until more convincing data are available, it may be prudent to investigate for GERD as a potential cofactor or initiating factor in patients with chronic sinusitis when no other etiology exists, or in those whose symptoms are unresponsive to conventional therapies. [source] Effect of inhaled corticosteroids on risk of development of cataract: a meta-analysisFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 3 2006Anup Uboweja Abstract The objective of this study was to quantify the risk of cataract among users of inhaled corticosteroids (ICS). Studies that examined the association of ICS use with risk of cataract were identified through computerized (MEDLINE, EMBASE), manual searches using Index Medicus, and checking cross-references to recover all published articles and scientific session abstracts. Pooled odds ratio (OR) with 95% confidence intervals (CI) were estimated using two methods, fixed effects Mantel,Haenszel model and random effects DerSimonian,Laird model. Four studies satisfied all the inclusion/exclusion criteria and were included in the analysis. The pooled OR (95% CI) by the Mantel,Haenszel method was 1.48 (1.39,1.57) and by the DerSimonian,Laird method was 1.48 (1.30,1.68). The test for heterogeneity was not significant. A total number of nine negative studies would be required to make the results of our meta-analysis non-significant. Number needed to harm is 16 with 95% CI of 13,19. Contrary to popular belief, inhaled ICS may be associated with systemic side effects like cataract as shown by this meta-analysis. The risk of increased cataract shown in our analysis needs to be weighted against the benefits of ICS. Further evaluations are required to clarify the causal association between the dosage and duration of drug use. [source] Helicobacter pylori Infection and Iron Stores: A Systematic Review and Meta-analysisHELICOBACTER, Issue 5 2008Khitam Muhsen Abstract Background and Aims:, We carried out a systematic literature review and meta-analysis to evaluate the existing evidence on the association between Helicobacter pylori infection and iron stores. Methods:, Twelve case reports and case series, 19 observational epidemiologic studies and six intervention trials were included in the review. Results:, Although only few studies controlled for multiple potential confounders, most studies reported a positive association, linking between H. pylori and decreased body iron stores in symptomatic and asymptomatic H. pylori -infected subjects. H. pylori infection may be regarded as a risk factor for reduction in body iron stores and also for iron deficiency or iron deficiency anemia, especially in high-risk groups. The results of the meta-analysis of thoroughly designed and analyzed studies revealed an increased risk for iron deficiency anemia; pooled odds ratio (OR) 2.8 (95% confidence interval (CI) 1.9, 4.2) and also for iron deficiency; pooled OR 1.38 (95%CI 1.16,1.65) among H. pylori -infected subjects. The biologic mechanism by which H. pylori induces the alteration in the iron stores is not fully understood, but it seems to involve several pathways, including gastrointestinal blood loss, decrease in the absorption of dietary iron, and enhanced uptake of the iron by the bacterium. Conclusions:,H. pylori is associated with reduced iron stores. Future research is needed to determine whether this relationship is a causal association and to better understand its biologic mechanism. The impact of anti- H. pylori therapy on improvement of iron stores needs to be further evaluated in large and well-controlled trials. [source] Telithromycin-associated hepatotoxicity: Clinical spectrum and causality assessment of 42 cases,HEPATOLOGY, Issue 1 2009Allen D. Brinker Telithromycin is the first of a new class of ketolide antibiotics with increased activity against penicillin-resistant and erythromycin-resistant pneumococci. This agent received approval by the United States Food and Drug Administration (FDA) in 2004 for treatment of upper and lower respiratory infections. Following market introduction, spontaneous reports of telithromycin-associated hepatotoxicity, including frank liver failure, were received. To address these reports, an ad hoc group with expertise in spontaneous adverse events reporting and experience in evaluating drug-induced liver injury was formed, including members of the FDA, other federal agencies, and academia. The primary objective of this group was to adjudicate case reports of hepatic toxicity for causal attribution to telithromycin. After an initial screening of all cases of liver injury associated with telithromycin reported to FDA as of April 2006 by one of the authors, 42 cases were comprehensively reviewed and adjudicated. Five cases included a severe outcome of either death (n = 4) or liver transplantation (n = 1); more than half were considered highly likely or probable in their causal association with telithromycin. Typical clinical features were: short latency (median, 10 days) and abrupt onset of fever, abdominal pain, and jaundice, sometimes with the presence of ascites even in cases that resolved. Concurrence in assignment of causality increased after agreement on definitions of categories and interactive discussions. Conclusion: Telithromycin is a rare cause of drug-induced liver injury that may have a distinctive clinical signature and associated high mortality rate. Consensus for attribution of liver injury to a selected drug exposure by individual experts can be aided by careful definition of terminology and discussion. (HEPATOLOGY 2009;49:250-257.) [source] Measles virus and Crohn's disease: A critical appraisal of the current literatureINFLAMMATORY BOWEL DISEASES, Issue 1 2001Dr. Douglas J. Robertson Abstract The etiology of inflammatory bowel disease (IBD) is unknown. Recent reports in the literature have suggested that measles virus, both wild-type and vaccine-attenuated, might be a risk factor for Crohn's disease. We used the well-accepted Bradford-Hill criteria to evaluate the possible causal association between measles and IBD. Although the association may be biologically plausible, the literature lacks consistency, specificity, strength, and dose response. The current literature does not support an association between measles virus and IBD. [source] Current safety and tolerability issues in men with erectile dysfunction receiving PDE5 inhibitorsINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 9 2007W. J. G. Hellstrom Summary Aims:, Treatment of erectile dysfunction (ED) has been greatly advanced by the advent of phosphodiesterase type-5 (PDE5) inhibitors. Upon the introduction of these agents, their cardiovascular (CV) safety was a major concern, mainly due to their vasodilatory effects. We conducted an electronic literature review of data concerning the safety and tolerability issues of men with ED receiving PDE5 inhibitors. Results:, Although safety concerns have been raised, evaluation of CV safety and related adverse events in clinical trials has not revealed any atypical safety issues. Discussion:, No causal association has been established to date between non-arteritic anterior ischaemic optic neuropathy (NAION) and PDE5 inhibitors. In addition, there are established guidelines which provide recommendations for the safe and effective use of these agents in treating men with ED and associated comorbidities. Conclusions:, Clinical trial and postmarketing surveillance data confirm the safety and tolerability profile of the PDE5 inhibitors, even in patients with endothelial dysfunction-associated comorbidities. [source] Anorexia nervosa associated with right frontal brain lesionINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 8 2007Emmanuelle Houy MD Abstract Objective: A causal association of brain lesion to the physiopathology of anorexia nervosa will be discussed. Method: The authors report the case of a female patient who developed anorexia nervosa. A cavernoma, located on the frontal side of the right sylvian, was discovered by chance after a seizure. Results: Surgical treatment of the lesion resulted in complete remission of the eating disorder at two years follow-up. Conclusion: Evidence for organic brain contribution to anorexia nervosa is strong and can be illustrated by this case report of anorexia nervosa associated with cerebral tumour. [source] Dose,response relationship between periodontal inflamed surface area and HbA1c in type 2 DiabeticsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 4 2009Willem Nesse Abstract Background: A dose,response relationship between the amount of inflamed periodontal tissue and HbA1c level, might be indicative for a causal association between periodontitis and type 2 diabetes. Aim: To assess a dose,response relationship between the periodontal inflamed surface area (PISA), as a measure of the amount of inflamed periodontal tissue, and HbA1c levels in type 2 diabetics. Material and Methods: Forty consecutive dentate type 2 diabetics attending their general practitioner for regular check-up, underwent full-mouth probing pocket depth and bleeding on probing assessment. From these data PISA was calculated. HbA1c levels were retrieved from patients' medical files. The dose,response relationship between PISA and HbA1c levels was assessed using multiple linear regression analyses, controlling for factors that might influence PISA or HbA1c levels. Results: The higher the PISA of type 2 diabetics was, the higher their HbA1c levels were. On a group level, an increase of PISA with 333 mm2 was associated with a 1.0 percentage point increase of HbA1c, independent of the influence of other factors. Conclusion: On a group level, there is a dose,response relationship between PISA and HbA1c in type 2 diabetics. This might be an indication of a causal relationship between type 2 diabetes and periodontitis. [source] Non-cardiac chest pain: Prevalence of reflux disease and response to acid suppression in an Asian populationJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 2 2009Hanizam Mohd Abstract Background:, Gastroesophageal reflux disease is thought to be the commonest cause of ,non-cardiac chest pain'. The use of proton-pump inhibitors resulting in improvement in the chest pain symptom would support this causal association. Objectives:, To determine the prevalence of gastroesophageal reflux disease in non-cardiac chest pain and the response of chest pain to proton-pump inhibitor therapy. Methods:, Patients with recurrent angina-like chest pain and normal coronary angiogram were recruited. The frequency and severity of chest pain were recorded. All patients underwent esophagogastroduodenoscopy and 48-h Bravo ambulatory pH monitoring before receiving rabeprazole 20 mg bd for 2 weeks. Results:, The prevalence of gastroesophageal reflux disease was 66.7% (18/27). The improvement in chest pain score was significantly higher in reflux compared to non-reflux patients (P = 0.006). The proportion of patients with complete or marked/moderate improvement in chest pain symptoms were significantly higher in patients with reflux (15/18, 83.3%) compared to those without (1/9, 11.1%) (P < 0.001). Conclusion:, The prevalence of gastroesophageal reflux disease in patients with ,non-cardiac chest pain' was high. The response to treatment with proton-pump inhibitors in patients with reflux disease, but not in those without, underlined the critical role of acid reflux in a subset of patients with ,non-cardiac chest pain'. [source] Evidence for a causal association between oral polio vaccine and transverse myelitis: A case history and review of the LiteratureJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 4 2006Heath Kelly Abstract: A 6-month-old boy developed transverse myelitis 7 days after the receipt of oral polio vaccine (OPV). A paediatric neurologist confirmed the diagnosis when the boy was aged 9 years. The boy had received his first scheduled OPV at the age of 4 months and had developed immunity to serotypes 1 and 2 but not to serotype 3. A poliovirus type 3 was isolated from stool and throat specimens collected from the boy in the first 2 days after symptom onset. This was shown, in a World Health Organization accredited laboratory, to be a vaccine strain by nucleic acid probe hybridiztion and enzyme-linked immunosorbent assay. The boy subsequently developed immunity to poliovirus serotype 3. It is accepted that poliovirus infection can present occasionally as transverse myelitis. This is estimated to occur in 1:125,1:800 cases. It is also accepted that OPV can cause vaccine-associated paralytic polio with a frequency of approximately one case per 2.5 million doses of OPV distributed. It seems feasible therefore that OPV could cause transverse myelitis with a frequency of 1 in 300 million to one in two billion doses distributed. In a 1993 report from the Institute of Medicine of the National Acadamies of the United States pertaining to vaccine safety, theoretical criteria were advanced for the establishment of a causal relationship between a vaccine and a clinical outcome. The clinical history and laboratory results in this case satisfy these criteria, providing plausible evidence for the causal link between OPV and transverse myelitis. [source] Dietary iron overload in the African and hepatocellular carcinomaLIVER INTERNATIONAL, Issue 6 2007Michael C. Kew Abstract Dietary iron overload occurs commonly in parts of sub-Saharan Africa. It results from the consumption of large volumes of traditional beer that is home-brewed in iron pots or drums and consequently has a high iron content. The liver becomes iron overloaded and may develop portal fibrosis or, less often, cirrhosis. A genetic predisposition to the condition has been suggested, but no putative gene has yet been identified. Although originally believed not to cause hepatocellular carcinoma, recent case,control studies have shown African Blacks with dietary iron overload to be at increased risk for the tumour and a causal association has been confirmed in an animal model. The mechanisms of iron-induced malignant transformation are yet to be fully characterised, but the close association between cirrhosis and hepatocellular carcinoma in patients with hereditary haemochromatosis and the lesser association in those with dietary iron overload, suggests that chronic necroinflammatory hepatic disease contributes to the malignant transformation. Increased hepatic iron may, however, also be directly carcinogenic. Probable mechanisms include the generation of reactive oxygen intermediates and the resultant chronic oxidative stress that damages hepatocytes and proteins, causes lipid peroxidation, and induces strand breaks, DNA unwinding, and mutations in tumour-suppressor genes and critical DNA repair genes. [source] Long-term geobotanical observations of climate change impacts in the Scandes of West-Central SwedenNORDIC JOURNAL OF BOTANY, Issue 4 2004Leif Kullman In the context of projected future human-caused climate warming, the present study reports and analyses the performance of subalpine/alpine plants, vegetation and phytogeographical patterns during the past century of about 1 °C temperature rise. Historical baseline data of altitudinal limits of woody and non-woody plants in the southern Scandes of Sweden are compared with recent assessments of these limits at the same locations. The methodological approach also includes repeat photography, individual age determinations and analyses of permanent plots. At all levels, from trees to tiny herbs, and from high to low altitudes, the results converge to indicate a causal association between temperature rise and biotic evolution. The importance of snow cover phenology is particularly evident. Treeline advance since the early-20th century varies between 75 and 130 m, depending on species and site. Tendencies and potentials for further upshift in a near future are evident from the appearance of young saplings of all tree species, growing 400,700 m atop of the treeline. Subalpine/alpine plant species have shifted upslope by average 200 m. In addition, present-day repetitions of floristic inventories on two alpine mountain summits reveal increases of plant species richness by 58 and 67%, respectively, since the early-1950s. Obviously, many plants adjust their altitudinal ranges to new climatic regimes much faster than generally assumed. Nevertheless, plants have migrated upslope with widely different rates. This produces non-analogous alpine plant communities, i.e. peculiar mixtures of alpine and silvine species. The alpine region is shrinking (higher treeline), and the character of the remaining alpine vegetation landscape is changing. For example, extensive alpine grasslands are replacing snow bed plant communities. [source] Ocular adnexal lymphoma and Helicobacter pylori gastric infection,AMERICAN JOURNAL OF HEMATOLOGY, Issue 9 2010Didier Decaudin There is a causal association between Helicobacter pylori (Hp) gastric infection and the development of gastric MALT lymphoma. In contrast, the link between Hp gastric infection and the development of extragastric lymphoma has not been thoroughly investigated. We, therefore, studied the prevalence of gastric Hp infection at initial diagnosis of ophthalmologic and nonophthalmologic extragastric lymphoma patients. Three cohorts of patients were studied: a first one of 83 patients with OAL, a second one of 101 patients with extraophthalmologic extragastric lymphoma, and a third one of 156 control individuals (control) without malignant lymphoma. Gastric Hp infection was investigated by histopathological analysis and Hp -specific PCR assay on gastric biopsy tissue samples. We found gastric Hp infection in 37 OAL patients (45%), in 25 extraophthalmologic extragastric lymphoma cases (25%), and in 18 controls individuals (12%) (P < 0.0001 OAL/C and P < 0.01 OAL/extra-OAL cases). Gastritis was found in 51% and 9% of Hp -positive and Hp -negative lymphoma patients, respectively (P < 10,4). Gastric Hp infection only correlated with MALT/LPL lymphoma (P = 0.03). There is a significant association between gastric Hp infection and MALT/LPL OAL. This suggests a novel mechanism of indirect infection-associated lymphomagenesis whereby chronic local antigen stimulation would lead to the emergence of ectopic B-cell lymphoma. © 2010 Wiley-Liss, Inc. Am. J. Hematol. [source] Cytokines and type 1 diabetes complications: casual or causal association?PEDIATRIC DIABETES, Issue 1 2008Michael J Haller No abstract is available for this article. [source] Hemostatic complications of angiogenesis inhibitors in cancer patients,AMERICAN JOURNAL OF HEMATOLOGY, Issue 11 2008Francesca Elice Tumor vasculature and tumor-associated neo-angiogenesis have recently become major targets for rational drug design of antineoplastic agents. Five such agents with angiogenesis inhibiting activity (thalidomide, lenalidomide, bevacizumab, sunitinib, sorafenib) have already obtained US Food and Drug Administration approval for clinical use and many others have entered clinical trials. Vascular complications, including venous or arterial thromboembolism and hemorrhage, have emerged as relevant toxicities in several clinical trials with angiogenesis inhibitors. Given the well-known interplay between the blood clotting system, angiogenesis, and tumor growth, a better understanding of the impact of these new drugs on overall hemostatic balance is required. In this brief overview, we discuss the incidence of hemostatic complications, the likely pathogenetic mechanisms involved, and the critical need to establish in randomized clinical trials the usefulness of thrombosis prophylaxis to prevent these complications. Careful documentation of hemostatic complications during treatment with each of the new antiangiogenic drugs is warranted. Further studies are urgently required to better define the causal association of these new agents with hemostatic complications and to establish the best prophylactic strategy. Am. J. Hematol., 2008. © 2008 Wiley-Liss, Inc. [source] Cancer morbidity among Danish male urban bus drivers: A historical cohort studyAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 7 2010Anne Petersen MPH Abstract Objective To investigate whether urban bus drivers are at increased risk for cancer. Methods Urban bus drivers in a cohort established in 1978 in the three largest cities of Denmark were followed-up in the Danish Cancer Registry until the end of 2003, and relative risks for cancers were estimated. Results Of 2,037 men included 70% reported in 1978 that they smoked. The standardized incidence ratio (SIR) for cancer in comparison with that of other male residents of the three cities was 1.09 [1.0,1.2]. The excess was due mainly to increased risks for cancers of the bladder (SIR, 1.6; 1.2,2.0) and lung (1.2; 1.0,1.4). In an analysis with internal comparisons and adjustment for smoking, we found no significant associations between duration of employment and increased risks for cancers at these two sites. Conclusions In this long-term follow-up study we found little evidence of a causal association between employment as an urban bus driver in Denmark and subsequent cancer. Am. J. Ind. Med. 53:757,761, 2010. © 2010 Wiley-Liss, Inc. [source] Secular Trends in the Incidence of Female Breast Cancer in the United States, 1973,1998THE BREAST JOURNAL, Issue 2 2004Kiumarss Nasseri DVM Abstract: , Statistical modeling suggests a causal association between the rapid increase in the incidence of female breast cancer (FBC) in the United States and the widespread use of screening mammography. Additional support for this suggestion is a shift in the stage at diagnosis that consists of an increase in early stage diagnosis followed by a decrease in late-stage diagnosis. This has not been reported in the United States. The objective of this study was to examine the secular trends in the incidence of FBC in search of empirical support for this shift. FBC cases in the Surveillance, Epidemiology, and End Results (SEER) database from 1973 through 1998 were dichotomized into early and late detection based. Early detection included all the in situ and invasive cases with local spread. Late detection included cases with regional spread and distant metastasis. Joinpoint segmented regression modeling was used for trend analysis. Early detection in white and black women followed a similar pattern of significant increase in the early 1980s that continued through 1998 with slight modification in 1987. The expected shift in stage was noticed only for white women when the incidence of late detection in them began to decline in 1987. The incidence of late detection in black women has remained stable. These results provide further support for the previously implied causal association between the use of screening mammography and the increased incidence of FBC in the United States. It also shows that the expected stage shift appeared in white women 50,69 years of age after an estimated detection lead time (DLT) of about 5 years. This is the first estimate of DLT in the United States that is based on actual data. The subsequent increase in late detection in white women since 1993 may be due to changes in case management and the increased use of sentinel lymph node biopsy (SLNB) rather than changes in the etiology or biology of FBC., [source] Airway Epithelial Cell Senescence in the Lung AllograftAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2008S. M. Parker Chronic lung allograft dysfunction, manifesting as bronchiolitis obliterans syndrome (BOS), is characterized by airway epithelial injury, impaired epithelial regeneration and subsequent airway remodeling. Increased cellular senescence has been reported in renal and liver allografts affected by chronic allograft dysfunction but the significance of cellular senescence in the airway epithelium of the transplanted lung is unknown. Thirty-four lung transplant recipients, 20 with stable graft function and 14 with BOS, underwent transbronchial lung biopsy and histochemical studies for senescence markers in small airways. Compared to nontransplant control lung tissue (n = 9), lung allografts demonstrate significantly increased airway epithelial staining for senescence-associated beta galactosidase (SA ,-gal) (p = 0.0215), p16ink4a (p = 0.0002) and p21waf1/cip (p = 0.0138) but there was no difference in expression of these markers between stable and BOS affected recipients (p > 0.05). This preliminary cross-sectional study demonstrates that cellular senescence occurs with increased frequency in the airway epithelium of the lung allograft but does not establish any association between airway epithelial senescence and BOS. A prospective longitudinal study is required to better address any potential causal association between airway epithelial senescence in stable allograft recipients and the subsequent development of BOS. [source] Toxic epidermal necrolysis in a premature infant of 27 weeks' gestational ageBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2005K. Lohmeier Summary Toxic epidermal necrolysis (TEN) is very rare in the newborn period. So far, three cases of TEN in newborns have been reported worldwide. We report a premature infant of 27 weeks' gestational age with TEN at 4 weeks of age. Sepsis treated by an antibiotic combination regimen preceding the TEN was a common feature of all four cases. In our patient, coagulase-negative staphylococci could be identified by blood culture, whereas the previously reported patients suffered from Klebsiella pneumoniae sepsis or Escherichia coli sepsis. Possibly, the uniform association with septic infection in the cases of TEN in the neonatal period might hint at a causal association, thus differentiating it from TEN in older children or adults. [source] A cerebellar demyelinating lesion following treatment of acne with isotretinoinCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 2 2008M. Yaman Summary We report the case of a demyelinating lesion located in the left cerebellar region that developed 3 months after the onset of oral isotretionin treatment. In April 2001, 1 year before admission, the patient underwent cranial magnetic resonance imaging (MRI) because of endocrinological problems. This was found to be completely normal. In January 2002, oral isotretinoin treatment was started to treat severe acne. Three months after the onset of therapy, the patient reported lack of appetite, faintness and tinnitus. Her second cranial MRI scan showed a cerebellar lesion, and oral isotretinoin treatment was stopped (April 2002). One month after the cessation of oral isotretinoin treatment, the lesion became less prominent on the MRI scan, and after 3 months, it had disappeared. Although it is difficult to determine the causal association between the demyelinating cerebellar lesion and isotretinoin treatment, we would like to alert physicians to this possibility, because of the common usage of this drug in daily practice. [source] Marijuana use and depression among adults: testing for causal associationsADDICTION, Issue 10 2006Valerie S. Harder ABSTRACT Aim To determine whether marijuana use predicts later development of depression after accounting for differences between users and non-users of marijuana. Design An ongoing longitudinal survey of 12 686 men and women beginning in 1979. Setting The National Longitudinal Survey of Youth of 1979, a nationally representative sample from the United States. Participants A total of 8759 adults (age range 29,37 years) interviewed in 1994 had complete data on past-year marijuana use and current depression. Measurements Self-reported past-year marijuana use was tested as an independent predictor of later adult depression using the Center for Epidemiologic Studies,Depression questionnaire. Individual's propensity to use marijuana was calculated using over 50 baseline covariates. Findings Before adjusting for group differences, the odds of current depression among past-year marijuana users is 1.4 times higher (95% CI: 1.1, 1.9) than the odds of depression among the non-using comparison group. After adjustment, the odds of current depression among past-year marijuana users is only 1.1 times higher than the comparison group (95% CI: 0.8, 1.7). Similarly, adjustment eliminates significant associations between marijuana use and depression in four additional analyses: heavy marijuana use as the risk factor, stratifying by either gender or age, and using a 4-year lag-time between marijuana use and depression. Conclusions After adjusting for differences in baseline risk factors of marijuana use and depression, past-year marijuana use does not significantly predict later development of depression. These findings are discussed in terms of their relevance for understanding possible causal effects of marijuana use on depression. [source] Breast cancer and microbial cancer incidence in female populations around the world: A surprising hyperbolic associationINTERNATIONAL JOURNAL OF CANCER, Issue 5 2008Anamaria Savu Abstract Current literature on cancer epidemiology typically discusses etiology of cancer by cancer type. Risks of different cancer types are, however, correlated at population level and may provide etiological clues. We showed previously an unexpected very high positive correlation between breast cancer (BC) and young-adult Hodgkin disease incidence rates. In a population-based case,control study of BC, older ages at the first Epstein,Barr virus exposure, indicated by older ages at onset of infectious mononucleosis, were associated with elevated BC risk. Here we examine BC risk in association with microbial cancer (MC) risk in female populations across the world. MC cancers are cervical, liver and stomach cancers with established causal associations with human papillomaviruses, hepatitis viruses, and helicobacter pylori, respectively. We examined age-adjusted BC and MC incidence rates in 74 female populations around the world with cancer registries. Our analysis suggests that BC and MC rates are inversely associated in a special mathematical form such that the product of BC rate and MC rate is approximately constant across world female populations. A differential equation model with solutions consistent to the observed inverse association was derived. BC and MC rates were modeled as functions of an exposure level to unspecified common factors that influence the 2 rates. In conjunction with previously reported evidence, we submit a hypothesis that BC etiology may have an appreciable link with microbial exposures (and/or immunological responses to them), the lack of which, especially in early life, may elevate BC risk. © 2008 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||