scispace - formally typeset
Search or ask a question
Author

Tanvir Chowdhury Turin

Bio: Tanvir Chowdhury Turin is an academic researcher from University of Calgary. The author has contributed to research in topics: Population & Kidney disease. The author has an hindex of 40, co-authored 233 publications receiving 6187 citations. Previous affiliations of Tanvir Chowdhury Turin include Libin Cardiovascular Institute of Alberta & Nagoya University.


Papers
More filters
Journal ArticleDOI
25 Jun 2014-JAMA
TL;DR: Declines in estimated GFR smaller than a doubling of serum creatinine concentration occurred more commonly and were strongly and consistently associated with the risk of ESRD and mortality, supporting consideration of lesser declines in Estimated GFR (such as a 30% reduction over 2 years) as an alternative end point for CKD progression.
Abstract: IMPORTANCE: The established chronic kidney disease (CKD) progression end point of end-stage renal disease (ESRD) or a doubling of serum creatinine concentration (corresponding to a change in estimated glomerular filtration rate [GFR] of −57% or greater) is a late event.OBJECTIVE: To characterize the association of decline in estimated GFR with subsequent progression to ESRD with implications for using lesser declines in estimated GFR as potential alternative end points for CKD progression. Because most people with CKD die before reaching ESRD, mortality risk also was investigated.DATA SOURCES AND STUDY SELECTION: Individual meta-analysis of 1.7 million participants with 12,344 ESRD events and 223,944 deaths from 35 cohorts in the CKD Prognosis Consortium with a repeated measure of serum creatinine concentration over 1 to 3 years and outcome data.DATA EXTRACTION AND SYNTHESIS: Transfer of individual participant data or standardized analysis of outputs for random-effects meta-analysis conducted between July 2012 and September 2013, with baseline estimated GFR values collected from 1975 through 2012.MAIN OUTCOMES AND MEASURES: End-stage renal disease (initiation of dialysis or transplantation) or all-cause mortality risk related to percentage change in estimated GFR over 2 years, adjusted for potential confounders and first estimated GFR.RESULTS: The adjusted hazard ratios (HRs) of ESRD and mortality were higher with larger estimated GFR decline. Among participants with baseline estimated GFR of less than 60 mL/min/1.73 m2, the adjusted HRs for ESRD were 32.1 (95% CI, 22.3-46.3) for changes of −57% in estimated GFR and 5.4 (95% CI, 4.5-6.4) for changes of −30%. However, changes of −30% or greater (6.9% [95% CI, 6.4%-7.4%] of the entire consortium) were more common than changes of −57% (0.79% [95% CI, 0.52%-1.06%]). This association was strong and consistent across the length of the baseline period (1 to 3 years), baseline estimated GFR, age, diabetes status, or albuminuria. Average adjusted 10-year risk of ESRD (in patients with a baseline estimated GFR of 35 mL/min/1.73 m2) was 99% (95% CI, 95%-100%) for estimated GFR change of −57%, was 83% (95% CI, 71%-93%) for estimated GFR change of −40%, and was 64% (95% CI, 52%-77%) for estimated GFR change of −30% vs 18% (95% CI, 15%-22%) for estimated GFR change of 0%. Corresponding mortality risks were 77% (95% CI, 71%-82%), 60% (95% CI, 56%-63%), and 50% (95% CI, 47%-52%) vs 32% (95% CI, 31%-33%), showing a similar but weaker pattern.CONCLUSIONS AND RELEVANCE: Declines in estimated GFR smaller than a doubling of serum creatinine concentration occurred more commonly and were strongly and consistently associated with the risk of ESRD and mortality, supporting consideration of lesser declines in estimated GFR (such as a 30% reduction over 2 years) as an alternative end point for CKD progression.

742 citations

Journal ArticleDOI
TL;DR: The existence of higher stroke rates and lower CHD rates in Asian countries than in Western countries and the respective risk factors for this are discussed on the basis of extensive reviews of cohort studies and whether these risk factors differ from those of Western countries are discussed.
Abstract: Cardiovascular disease (CVD) prevention in Asia is an important issue for world health, because half of the world’s population lives in Asia. Asian countries and regions such as Japan, the Republic of Korea, the People’s Republic of China, Hong Kong, Taiwan, and the Kingdom of Thailand have greater mortality and morbidity from stroke than from coronary heart disease (CHD), whereas the opposite is true in Western countries.1 The reasons why this specific situation is observed in countries with rapid and early-phase westernization, such as Japan and South Korea, are very interesting. The Seven Countries Study conducted by Keys et al2 in 1957 found that Japanese populations had lower fat intake, lower serum total cholesterol, and lower CHD than populations in the United States and Scandinavia, in spite of higher smoking rates. The serum total cholesterol level in Japan has increased rapidly since World War II in accordance with an increase in dietary fat intake from 10% of total energy intake per capita per day to 25%.1,2 Despite this increase, the specific characteristic of lower CHD incidence and mortality than that in Western countries has persisted.3,4 Whether Japanese people and certain other Asian populations have different risk factors for CHD than Western populations has been a subject of discussion for quite some time. In this article, we discuss the existence of higher stroke rates and lower CHD rates in Asian countries than in Western countries and the respective risk factors for this on the basis of extensive reviews of cohort studies. We also discuss whether these risk factors differ from those of Western countries. Along with this, we examine the relationship between serum total cholesterol and total stroke and its subtypes. We also address the emerging problems and important issues for CVD prevention in Asia. An extensive …

619 citations

Journal ArticleDOI
TL;DR: The importance of including appropriate variables, following the proper steps, and adopting the proper methods when selecting variables for prediction models is focused on.
Abstract: Clinical prediction models are used frequently in clinical practice to identify patients who are at risk of developing an adverse outcome so that preventive measures can be initiated. A prediction model can be developed in a number of ways; however, an appropriate variable selection strategy needs to be followed in all cases. Our purpose is to introduce readers to the concept of variable selection in prediction modelling, including the importance of variable selection and variable reduction strategies. We will discuss the various variable selection techniques that can be applied during prediction model building (backward elimination, forward selection, stepwise selection and all possible subset selection), and the stopping rule/selection criteria in variable selection (p values, Akaike information criterion, Bayesian information criterion and Mallows’ Cp statistic). This paper focuses on the importance of including appropriate variables, following the proper steps, and adopting the proper methods when selecting variables for prediction models.

284 citations

Journal ArticleDOI
TL;DR: In this article, the authors used Cox regression models to assess independent associations between HbA 1c level and five study outcomes (death, progression of kidney disease based on a doubling of serum creatinine level, or new end-stage renal disease, cardiovascular events, all-cause hospitalization).
Abstract: Background Better glycemic control as reflected by lower hemoglobin A 1c (HbA 1c ) level may prevent or slow progression of nephropathy in people with diabetes mellitus (DM). Whether a lower HbA 1c level improves outcomes in people with DM and chronic kidney disease (CKD) is unknown. Methods From all people with serum creatinine measured as part of routine care in a single Canadian province from 2005 through 2006, we identified those with CKD based on laboratory data (estimated glomerular filtration rate [eGFR], 2 ]) and DM using a validated algorithm applied to hospitalization and claims data. Patients were classified based on their first HbA 1c measurement; Cox regression models were used to assess independent associations between HbA 1c level and 5 study outcomes (death, progression of kidney disease based on a doubling of serum creatinine level, or new end-stage renal disease [ESRD], cardiovascular events, all-cause hospitalization). Results We identified 23 296 people with DM and an eGFR lower than 60.0 mL/min/1.73 m 2 . The median HbA 1c level was 6.9% (range, 2.8%-20.0%), and 11% had an HbA 1c value higher than 9%. Over the median follow-up period of 46 months, 3665 people died, and 401 developed ESRD. Regardless of baseline eGFR, a higher HbA 1c level was strongly and independently associated with excess risk of all 5 outcomes studied (P 1c levels lower than 6.5% and higher than 8.0%. The increased risk of ESRD associated with a higher HbA 1c level was attenuated at a lower baseline eGFR (P value for interaction, 2 , the risk of ESRD was increased by 22% and 152% in patients with HbA 1c levels of 7% to 9% and higher than 9%, respectively, compared with patients with an HbA 1c level lower than 7% (P 2 . Conclusions A hemoglobin A 1c level higher than 9% is common in people with non–hemodialysis-dependent CKD and is associated with markedly worse clinical outcomes; lower levels of HbA 1c ( 1c level was most pronounced among people with better kidney function. These findings suggest that appropriate and timely control of HbA 1c level in people with DM and CKD may be more important than previously realized, but suggest also that intensive glycemic control (HbA 1c level <6.5%) may be associated with increased mortality.

211 citations

Journal ArticleDOI
TL;DR: It is concluded that there is ample evidence for a high prevalence of the problem, and research in this area should now expand towards initiatives to improve general sleep education for medical students, identify students at risk, and target them with programs to improve sleep.
Abstract: Medical students carry a large academic load which could potentially contribute to poor sleep quality above and beyond that already experienced by modern society. In this global literature review o...

209 citations


Cited by
More filters
Journal ArticleDOI
01 May 2014
TL;DR: There is substantial global variation in the relative burden of stroke compared with IHD, and the disproportionate burden from stroke for many lower-income countries suggests that distinct interventions may be required.
Abstract: Background—Although stroke and ischemic heart disease (IHD) have several well-established risk factors in common, the extent of global variation in the relative burdens of these forms of vascular disease and reasons for any observed variation are poorly understood. Methods and Results—We analyzed mortality and disability-adjusted life-year loss rates from stroke and IHD, as well as national estimates of vascular risk factors that have been developed by the World Health Organization Burden of Disease Program. National income data were derived from World Bank estimates. We used linear regression for univariable analysis and the Cuzick test for trends. Among 192 World Health Organization member countries, stroke mortality rates exceeded IHD rates in 74 countries (39%), and stroke disability-adjusted life-year loss rates exceeded IHD rates in 62 countries (32%). Stroke mortality ranged from 12.7% higher to 27.2% lower than IHD, and stroke disability-adjusted life-year loss rates ranged from 6.2% higher to 10.2% lower than IHD. Stroke burden was disproportionately higher in China, Africa, and South America, whereas IHD burden was higher in the Middle East, North America, Australia, and much of Europe. Lower national income was associated with higher relative mortality (P 0.001) and burden of disease (P 0.001) from stroke. Diabetes mellitus prevalence and mean serum cholesterol were each associated with greater relative burdens from IHD even after adjustment for national income. Conclusions—There is substantial global variation in the relative burden of stroke compared with IHD. The disproportionate burden from stroke for many lower-income countries suggests that distinct interventions may be required. (Circulation. 2011; 124:314-323.)

7,265 citations

Journal ArticleDOI
TL;DR: This year's edition of the Statistical Update includes data on the monitoring and benefits of cardiovascular health in the population, metrics to assess and monitor healthy diets, an enhanced focus on social determinants of health, a focus on the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors, implementation strategies, and implications of the American Heart Association’s 2020 Impact Goals.
Abstract: Background: The American Heart Association, in conjunction with the National Institutes of Health, annually reports on the most up-to-date statistics related to heart disease, stroke, and cardiovas...

5,078 citations

Journal ArticleDOI
21 Jul 1979-BMJ
TL;DR: It is suggested that if assessment of overdoses were left to house doctors there would be an increase in admissions to psychiatric units, outpatients, and referrals to social services, but for house doctors to assess overdoses would provide no economy for the psychiatric or social services.
Abstract: admission. This proportion could already be greater in some parts of the country and may increase if referrals of cases of self-poisoning increase faster than the facilities for their assessment and management. The provision of social work and psychiatric expertise in casualty departments may be one means of preventing unnecessary medical admissions without risk to the patients. Dr Blake's and Dr Bramble's figures do not demonstrate, however, that any advantage would attach to medical teams taking over assessment from psychiatrists except that, by implication, assessments would be completed sooner by staff working on the ward full time. What the figures actually suggest is that if assessment of overdoses were left to house doctors there would be an increase in admissions to psychiatric units (by 19°U), outpatients (by 5O°'), and referrals to social services (by 140o). So for house doctors to assess overdoses would provide no economy for the psychiatric or social services. The study does not tell us what the consequences would have been for the six patients who the psychiatrists would have admitted but to whom the house doctors would have offered outpatient appointments. E J SALTER

4,497 citations

Journal ArticleDOI
TL;DR: The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascul...
Abstract: Background: The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascul...

3,034 citations

Journal ArticleDOI
01 Jun 2012-Stroke
TL;DR: Evidence-based guidelines are presented for the care of patients presenting with aneurysmal subarachnoid hemorrhage and offer a framework for goal-directed treatment of the patient with aSAH.
Abstract: Purpose—The aim of this guideline is to present current and comprehensive recommendations for the diagnosis and treatment of aneurysmal subarachnoid hemorrhage (aSAH). Methods—A formal literature s...

2,713 citations