Clinical Trial Service Unit

About: Clinical Trial Service Unit is a based out in . It is known for research contribution in the topics: Population & Stroke. The organization has 428 authors who have published 1387 publications receiving 181920 citations.

The Burden of Hypertension and Associated Risk for Cardiovascular Mortality in China

Abstract: Importance Hypertension is a leading cause of premature death in China, but limited evidence is available on the prevalence and management of hypertension and its effect on mortality from cardiovascular disease (CVD). Objectives To examine the prevalence, diagnosis, treatment, and control of hypertension and to assess the CVD mortality attributable to hypertension in China. Design, Setting and Participants This prospective cohort study (China Kadoorie Biobank Study) recruited 500 223 adults, aged 35 to 74 years, from the general population in China. Blood pressure (BP) measurements were recorded as part of the baseline survey from June 25, 2004, to August 5, 2009, and 7028 deaths due to CVD were recorded before January 1, 2014 (mean duration of follow-up: 7.2 years). Data were analyzed from June 9, 2014, to July 17, 2015. Exposures Prevalence and diagnosis of hypertension (systolic BP ≥140 mm Hg, diastolic BP ≥90 mm Hg, or receiving treatment for hypertension) and treatment and control rates overall and in various population subgroups. Main Outcomes and Measures Cox regression analysis yielded age- and sex-specific rate ratios for deaths due to CVD comparing participants with and without uncontrolled hypertension, which were used to estimate the number of CVD deaths attributable to hypertension. Results The cohort included 205 167 men (41.0%) and 295 056 women (59.0%) with a mean (SD) age of 52 (10) years for both sexes. Overall, 32.5% of participants had hypertension; the prevalence increased with age (from 12.6% at 35-39 years of age to 58.4% at 70-74 years of age) and varied substantially by region (range, 22.7%-40.7%). Of those with hypertension, 30.5% had received a diagnosis from a physician; of those with a diagnosis of hypertension, 46.4% were being treated; and of those treated, 29.6% had their hypertension controlled (ie, systolic BP Conclusions and Relevance About one-third of Chinese adults in this national cohort population had hypertension. The levels of diagnosis, treatment, and control were much lower than in Western populations, and were associated with significant excess mortality.

Cohort Profile: The Kadoorie Study of Chronic Disease in China (KSCDC)

Abstract: During recent decades China has undergone a rapid transition in the main disease patterns of its population. There has been a substantial decrease in maternal and child mortality and in adult mortality from themain infectious/parasitic diseases, whereas for ischaemic heart disease and some other non-communicable chronic diseases, there has been a moderate increase in mortality rates, at least in some parts of China. Consequently, most of the premature mortality that still remains in China now involves the chronic diseases of middle age, such as cancer, stroke, heart disease, or chronic lung disease. 1–4 In the mid-1970s a retrospective survey of the causes of 20 million deaths in China during 1973–75 showed that for each major disease there was large unexplained variation in the age-specific rates between different parts of China, indicating that there must be some large avoidable causes. 5 This finding was confirmed and extended in the late 1980s by a more careful retrospective survey of the causes of one million deaths during 1986–88 in 69 rural counties and 24 cities (Figure 1). 3,4 These big differences in disease rates between one area and another probably reflect differences in the ways people live rather than genetic differences. Moreover, even within one area there are likely to be substantial differences between individuals in genetic factors, as well as in patterns of chronic infection, personal biochemistry, physical characteristics, lifestyle, etc. that persist for many years and eventually influence the likelihood of particular individuals developing particular diseases. 3,4

Cardiac exposures in breast cancer radiotherapy: 1950s-1990s.

Abstract: Purpose To estimate the doses to the heart and coronary arteries from common breast cancer radiotherapy (RT) regimens used worldwide from the 1950s to the 1990s. Methods and Materials Virtual simulation and computed tomography planning were used to reconstruct the megavoltage and electron regimens. Manual planning was used for the orthovoltage and brachytherapy regimens. Several sources of variability associated with the dose estimates were assessed. Results Breast or chest wall RT resulted in whole heart doses of 0.9–14 Gy for left-sided and of 0.4–6 Gy for right-sided irradiation. Internal mammary chain RT delivered heart doses of 3–17 Gy and 2–10 Gy for left- and right-sided irradiation, respectively. For most regimens, the dose to the left anterior descending coronary artery was greater than the heart dose. Scar boost, supraclavicular fossa, and axillary RT delivered mean cardiac doses of ≤3 Gy. The greatest source of variability in estimating dose from a given regimen was patient anatomy. Conclusion For most techniques, the greatest radiation doses were received by the anterior part of the heart and the left anterior descending coronary artery, a common site of atherosclerosis causing myocardial infarction. Irradiation of these structures might have contributed to the excess risk of death from heart disease seen after some past breast cancer RT regimens.