264 research outputs found
Multiple sclerosis epidemiology in Middle East and North Africa: A systematic review and meta-analysis
Background: Multiple sclerosis (MS) is one of the most common neurological disorders and a leading cause of nontraumatic disability in young adults in many countries. Recent reports from the Middle East and North Africa have suggested a moderate to high risk of MS in these countries. Methods: A literature search was performed in August 2014 in MEDLINE, EMBASE, and IMEMR to retrieve original population-based studies on MS epidemiology in the Middle East and North African countries published between 1st January 1985 and 1st August 2014. We designed search strategies using the key words: MS, prevalence, incidence, and epidemiology. According to the inclusion criteria, 52 studies were included in this systematic review. Results: McDonald's criteria were the most widely used diagnostic criteria in the studies. Most studies were conducted in single hospitalbased centers with a defined catchment area. The female/male ratio ranged from 0.8 in Oman to 4.3 in Saudi Arabia. MS prevalence ranged from 14.77/100,000 population in Kuwait (2000) to 101.4/100,000 in Turkey (2006). The overall MS prevalence in the region was 51.52/100,000. The mean age at disease onset ranged from 25.2 years in Kuwait to 32.5 years in Northeastern Iran, with an overall estimate of 28.54 years. Conclusions: Recent advances in MS registries will allow nation-wide studies and temporal comparisons between countries, provided that age- and sex-standardized estimates are available. © 2015 S. Karger AG, Basel
Air pollution, a rising environmental risk factor for cognition, neuroinflammation and neurodegeneration: The clinical impact on children and beyond
International audienceAir pollution (indoors and outdoors) is a major issue in public health as epidemiological studies have highlighted its numerous detrimental health consequences (notably, respiratory and cardiovascular pathological conditions). Over the past 15 years, air pollution has also been considered a potent environmental risk factor for neurological diseases and neuropathology. This review examines the impact of air pollution on children's brain development and the clinical, cognitive, brain structural and metabolic consequences. Long-term potential consequences for adults’ brains and the effects on multiple sclerosis (MS) are also discussed. One challenge is to assess the effects of lifetime exposures to outdoor and indoor environmental pollutants, including occupational exposures: how much, for how long and what type. Diffuse neuroinflammation, damage to the neurovascular unit, and the production of autoantibodies to neural and tight-junction proteins are worrisome findings in children chronically exposed to concentrations above the current standards for ozone and fine particulate matter (PM2.5), and may constitute significant risk factors for the development of Alzheimer's disease later in life. Finally, data supporting the role of air pollution as a risk factor for MS are reviewed, focusing on the effects of PM10 and nitrogen oxide
Air pollution, environmental chemicals, and smoking may trigger vitamin D deficiency: Evidence and potential mechanisms
Beyond vitamin D (VD) effect on bone homeostasis, numerous physiological functions in human health have been described for this versatile prohormone. In 2016, 95% of the world's population lived in areas where annual mean ambient particulate matter (<2.5 μm) levels exceeded the World Health Organization guideline value (Shaddick et al., 2018). On the other hand, industries disperse thousands of chemicals continually into the environment. Further, considerable fraction of populations are exposed to tobacco smoke. All of these may disrupt biochemical pathways and cause detrimental consequences, such as VD deficiency (VDD). In spite of the remarkable number of studies conducted on the role of some of the above mentioned exposures on VDD, the literature suffers from two main shortcomings: (1) an overview of the impacts of environmental exposures on the levels of main VD metabolites, and (2) credible engaged mechanisms in VDD because of those exposures. To summarize explanations for these unclear topics, we conducted the present review, using relevant keywords in the PubMed database, to investigate the adverse effects of exposure to air pollution, some environmental chemicals, and smoking on the VD metabolism, and incorporate relevant potential pathways disrupting VD endocrine system (VDES) leading to VDD. Air pollution may lead to the reduction of VD cutaneous production either directly by blocking ultraviolet B photons or indirectly by decreasing outdoor activity. Heavy metals may reduce VD serum levels by increasing renal tubular dysfunction, as well as downregulating the transcription of cytochrome P450 mixed-function oxidases (CYPs). Endocrine-disrupting chemicals (EDCs) may inhibit the activity and expression of CYPs, and indirectly cause VDD through weight gain and dysregulation of thyroid hormone, parathyroid hormone, and calcium homeostasis. Smoking through several pathways decreases serum 25(OH)D and 1,25(OH)2D levels, VD intake from diet, and the cutaneous production of VD through skin aging. In summary, disturbance in the cutaneous production of cholecalciferol, decreased intestinal intake of VD, the modulation of genes involved in VD homeostasis, and decreased local production of calcitriol in target tissues are the most likely mechanisms that involve in decreasing the serum VD level
Association of Zinc, Copper and Magnesium with bone mineral density in Iranian postmenopausal women - a case control study
Background: The risk of inadequate nutrition such as trace elements and vitamin deficiencies is considerable in postmenopausal women. The aim of this study was to compare trace elements (Zinc, Copper and Magnesium) concentration in nail, urine and serum among osteoporotic postmenopausal women with control group in Iran.Methods: Forty eight postmenopausal women aged 36-60 years, were recruited, consisting 30 osteoporotic patients and 18 healthy controls. Blood, nail and urine concentration of Zinc (Zn), copper (Cu) and magnesium (Mg) were determined using Inductively Coupled Plasma -Atomic Emission Spectrometry (ICP-AES) method. Their Bone Mineral Density was measured by Dual X-ray Absorption (DEXA) method.Results: The urine level of trace elements had significant difference between osteoporotic groups and controls (p < 0.001). Moreover Mg level significantly differed in serum between two groups (p < 0.04). There was no statistically significant difference in trace minerals in nail beyond groups.Conclusion: Our findings indicate that Urine Zn level could be considerable an appropriate marker for bone absorption, usage of Zn supplements in postmenopausal women may result a beneficial reduction in osteoporotic risk. © 2014 Razmandeh et al.; licensee BioMed Central Ltd
Medical podcasting in Iran; pilot, implementation and attitude evaluation
Podcasting has become a popular means of transferring knowledge in higher education through making lecture contents available to students at their convenience. Accessing courses on media players provides students with enhanced learning opportunities. Development of teaching methods able to cope with ever-changing nature of medicine is crucial to train the millennium students. Pharmacology education in Tehran University of Medical Sciences has been based on lectures so far; our aim was to implement a pilot study to evaluate the advantages and disadvantages of offering the course contents as podcasts as well as evaluating whether such program can be feasible in our educational program. 46% of students downloaded the podcast according to our download center. 48% favored usage of both internet and DVD-ROM concurrently. Overall 96% of students perceived that podcasting had a positive impact on their learning in pharmacology course. Our results indicate that most of attendants proposed the positive yields of podcasting despite low usage of it, mainly as a pre-class preparing tool.publisher versio
Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015
SummaryBackground The Global Burden of Diseases, Injuries, and Risk Factors Study 2015 provides an up-to-date synthesis of the evidence for risk factor exposure and the attributable burden of disease. By providing national and subnational assessments spanning the past 25 years, this study can inform debates on the importance of addressing risks in context. Methods We used the comparative risk assessment framework developed for previous iterations of the Global Burden of Disease Study to estimate attributable deaths, disability-adjusted life-years (DALYs), and trends in exposure by age group, sex, year, and geography for 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks from 1990 to 2015. This study included 388 risk-outcome pairs that met World Cancer Research Fund-defined criteria for convincing or probable evidence. We extracted relative risk and exposure estimates from randomised controlled trials, cohorts, pooled cohorts, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. We developed a metric that allows comparisons of exposure across risk factors—the summary exposure value. Using the counterfactual scenario of theoretical minimum risk level, we estimated the portion of deaths and DALYs that could be attributed to a given risk. We decomposed trends in attributable burden into contributions from population growth, population age structure, risk exposure, and risk-deleted cause-specific DALY rates. We characterised risk exposure in relation to a Socio-demographic Index (SDI). Findings Between 1990 and 2015, global exposure to unsafe sanitation, household air pollution, childhood underweight, childhood stunting, and smoking each decreased by more than 25%. Global exposure for several occupational risks, high body-mass index (BMI), and drug use increased by more than 25% over the same period. All risks jointly evaluated in 2015 accounted for 57·8% (95% CI 56·6–58·8) of global deaths and 41·2% (39·8–42·8) of DALYs. In 2015, the ten largest contributors to global DALYs among Level 3 risks were high systolic blood pressure (211·8 million [192·7 million to 231·1 million] global DALYs), smoking (148·6 million [134·2 million to 163·1 million]), high fasting plasma glucose (143·1 million [125·1 million to 163·5 million]), high BMI (120·1 million [83·8 million to 158·4 million]), childhood undernutrition (113·3 million [103·9 million to 123·4 million]), ambient particulate matter (103·1 million [90·8 million to 115·1 million]), high total cholesterol (88·7 million [74·6 million to 105·7 million]), household air pollution (85·6 million [66·7 million to 106·1 million]), alcohol use (85·0 million [77·2 million to 93·0 million]), and diets high in sodium (83·0 million [49·3 million to 127·5 million]). From 1990 to 2015, attributable DALYs declined for micronutrient deficiencies, childhood undernutrition, unsafe sanitation and water, and household air pollution; reductions in risk-deleted DALY rates rather than reductions in exposure drove these declines. Rising exposure contributed to notable increases in attributable DALYs from high BMI, high fasting plasma glucose, occupational carcinogens, and drug use. Environmental risks and childhood undernutrition declined steadily with SDI; low physical activity, high BMI, and high fasting plasma glucose increased with SDI. In 119 countries, metabolic risks, such as high BMI and fasting plasma glucose, contributed the most attributable DALYs in 2015. Regionally, smoking still ranked among the leading five risk factors for attributable DALYs in 109 countries; childhood underweight and unsafe sex remained primary drivers of early death and disability in much of sub-Saharan Africa. Interpretation Declines in some key environmental risks have contributed to declines in critical infectious diseases. Some risks appear to be invariant to SDI. Increasing risks, including high BMI, high fasting plasma glucose, drug use, and some occupational exposures, contribute to rising burden from some conditions, but also provide opportunities for intervention. Some highly preventable risks, such as smoking, remain major causes of attributable DALYs, even as exposure is declining. Public policy makers need to pay attention to the risks that are increasingly major contributors to global burden. Funding Bill & Melinda Gates Foundation
The burden of headache disorders in the Eastern Mediterranean Region, 1990-2016: Findings from the Global Burden of Disease study 2016
Objectives: Using the findings of the Global Burden of Disease Study (GBD), we report the burden of primary headache disorders in the Eastern Mediterranean Region (EMR) from 1990 to 2016. Methods: We modelled headache disorders using DisMod-MR 2.1 Bayesian meta-regression tool to ensure consistency between prevalence, incidence, and remission. Years lived with disability (YLDs) were calculated by multiplying prevalence and disability weight (DW) of migraine and tension-type headache (TTH). We assumed primary headache disorders as non-fatal, so their YLD is equal to disability-adjusted life years (DALYs). Results: Migraine and TTH were the second and twentieth leading causes of YLDs in EMR. Between 1990 and 2016, the absolute YLD numbers of migraine and TTH increased from 2.3 million (95 uncertainty interval (UI): 1.5-3.2) to 4.7 million (95UI: 3-6.5) and from 383 thousand (95UI: 240-562) to 816 thousand (95UI: 516-1221), respectively. During the same period, age-standardised YLD rates of migraine and TTH in EMR increased by 0.7 and 2.5, respectively, in comparison to a small decrease in the global rates (0.2 decrease in migraine and TTH). The bulk of burden due to headache occurred in the 30-49 year age group, with a peak at ages 35-44 years. The age-standardised YLD rates of both headache disorders were higher in women with female to male ratio of 1.69 for migraine and 1.38 for TTH. All countries of the EMR except for Somalia and Djibouti had higher age-standardised YLD rates for migraine and TTH in compare to the global rates. Libya and Saudi Arabia had the highest increase in age-standardised YLD rates of migraine and TTH, respectively. Conclusion: The findings of this study show that primary headache disorders are a major and a growing cause of disability in EMR. Since 1990, burden of primary headache disorders has constantly been higher in EMR compared to rest of the world, which indicates that health systems in EMR must focus further on developing and implementing preventive and management strategies to control headache. © 2019 The Author(s)
The burden of headache disorders in the Eastern Mediterranean Region, 1990-2016: Findings from the Global Burden of Disease study 2016
Objectives: Using the findings of the Global Burden of Disease Study (GBD), we report the burden of primary headache disorders in the Eastern Mediterranean Region (EMR) from 1990 to 2016. Methods: We modelled headache disorders using DisMod-MR 2.1 Bayesian meta-regression tool to ensure consistency between prevalence, incidence, and remission. Years lived with disability (YLDs) were calculated by multiplying prevalence and disability weight (DW) of migraine and tension-type headache (TTH). We assumed primary headache disorders as non-fatal, so their YLD is equal to disability-adjusted life years (DALYs). Results: Migraine and TTH were the second and twentieth leading causes of YLDs in EMR. Between 1990 and 2016, the absolute YLD numbers of migraine and TTH increased from 2.3 million (95 uncertainty interval (UI): 1.5-3.2) to 4.7 million (95UI: 3-6.5) and from 383 thousand (95UI: 240-562) to 816 thousand (95UI: 516-1221), respectively. During the same period, age-standardised YLD rates of migraine and TTH in EMR increased by 0.7 and 2.5, respectively, in comparison to a small decrease in the global rates (0.2 decrease in migraine and TTH). The bulk of burden due to headache occurred in the 30-49 year age group, with a peak at ages 35-44 years. The age-standardised YLD rates of both headache disorders were higher in women with female to male ratio of 1.69 for migraine and 1.38 for TTH. All countries of the EMR except for Somalia and Djibouti had higher age-standardised YLD rates for migraine and TTH in compare to the global rates. Libya and Saudi Arabia had the highest increase in age-standardised YLD rates of migraine and TTH, respectively. Conclusion: The findings of this study show that primary headache disorders are a major and a growing cause of disability in EMR. Since 1990, burden of primary headache disorders has constantly been higher in EMR compared to rest of the world, which indicates that health systems in EMR must focus further on developing and implementing preventive and management strategies to control headache. © 2019 The Author(s)
Disability-adjusted life-years (DALYs) for 315 diseases and injuries and healthy life expectancy (HALE) in Iran and its neighboring countries, 1990–2015
BACKGROUND: Summary measures of health are essential in making estimates of health status that are comparable across time and place. They can be used for assessing the performance of health systems, informing effective policy making, and monitoring the progress of nations toward achievement of sustainable development goals. The Global Burden of Diseases, Injuries, and Risk Factors Study 2015 (GBD 2015) provides disability-adjusted life-years (DALYs) and healthy life expectancy (HALE) as main summary measures of health. We assessed the trends of health status in Iran and 15 neighboring countries using these summary measures. METHODS: We used the results of GBD 2015 to present the levels and trends of DALYs, life expectancy (LE), and HALE in Iran and its 15 neighboring countries from 1990 to 2015. For each country, we assessed the ratio of observed levels of DALYs and HALE to those expected based on socio-demographic index (SDI), an indicator composed of measures of total fertility rate, income per capita, and average years of schooling. RESULTS: All-age numbers of DALYs reached over 19 million years in Iran in 2015. The all-age number of DALYs has remained stable during the past two decades in Iran, despite the decreasing trends in all-age and age-standardized rates. The all-cause DALY rates decreased from 47,200 in 1990 to 28,400 per 100,000 in 2015. The share of non-communicable diseases in DALYs increased in Iran (from 42% to 74%) and all of its neighbors between 1990 and 2015; the pattern of change is similar in almost all 16 countries. The DALY rates for NCDs and injuries in Iran were higher than global rates and the average rate in High Middle SDI countries, while those for communicable, maternal, neonatal, and nutritional disorders were much lower in Iran. Among men, cardiovascular diseases ranked first in all countries of the region except for Bahrain. Among women, they ranked first in 13 countries. Life expectancy and HALE show a consistent increase in all countries. Still, there are dissimilarities indicating a generally low LE and HALE in Afghanistan and Pakistan and high expectancy in Qatar, Kuwait, and Saudi Arabia. Iran ranked 11th in terms of LE at birth and 12th in terms of HALE at birth in 1990 which improved to 9th for both metrics in 2015. Turkey and Iran had the highest increase in LE and HALE from 1990 to 2015 while the lowest increase was observed in Armenia, Pakistan, Kuwait, Kazakhstan, Russia, and Iraq. CONCLUSIONS: The levels and trends in causes of DALYs, life expectancy, and HALE generally show similarities between the 16 countries, although differences exist. The differences observed between countries can be attributed to a myriad of determinants, including social, cultural, ethnic, religious, political, economic, and environmental factors as well as the performance of the health system. Investigating the differences between countries can inform more effective health policy and resource allocation. Concerted efforts at national and regional levels are required to tackle the emerging burden of non-communicable diseases and injuries in Iran and its neighbors
Association of Factor V Leiden with Subsequent Atherothrombotic Events:A GENIUS-CHD Study of Individual Participant Data
BACKGROUND: Studies examining the role of factor V Leiden among patients at higher risk of atherothrombotic events, such as those with established coronary heart disease (CHD), are lacking. Given that coagulation is involved in the thrombus formation stage on atherosclerotic plaque rupture, we hypothesized that factor V Leiden may be a stronger risk factor for atherothrombotic events in patients with established CHD. METHODS: We performed an individual-level meta-analysis including 25 prospective studies (18 cohorts, 3 case-cohorts, 4 randomized trials) from the GENIUS-CHD (Genetics of Subsequent Coronary Heart Disease) consortium involving patients with established CHD at baseline. Participating studies genotyped factor V Leiden status and shared risk estimates for the outcomes of interest using a centrally developed statistical code with harmonized definitions across studies. Cox proportional hazards regression models were used to obtain age- and sex-adjusted estimates. The obtained estimates were pooled using fixed-effect meta-analysis. The primary outcome was composite of myocardial infarction and CHD death. Secondary outcomes included any stroke, ischemic stroke, coronary revascularization, cardiovascular mortality, and all-cause mortality. RESULTS: The studies included 69 681 individuals of whom 3190 (4.6%) were either heterozygous or homozygous (n=47) carriers of factor V Leiden. Median follow-up per study ranged from 1.0 to 10.6 years. A total of 20 studies with 61 147 participants and 6849 events contributed to analyses of the primary outcome. Factor V Leiden was not associated with the combined outcome of myocardial infarction and CHD death (hazard ratio, 1.03 [95% CI, 0.92-1.16]; I2=28%; P-heterogeneity=0.12). Subgroup analysis according to baseline characteristics or strata of traditional cardiovascular risk factors did not show relevant differences. Similarly, risk estimates for the secondary outcomes including stroke, coronary revascularization, cardiovascular mortality, and all-cause mortality were also close to identity. CONCLUSIONS: Factor V Leiden was not associated with increased risk of subsequent atherothrombotic events and mortality in high-risk participants with established and treated CHD. Routine assessment of factor V Leiden status is unlikely to improve atherothrombotic events risk stratification in this population
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