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Prevalence, Mortality, and Risk Factors
Published in Jahangir Moini, Matthew Adams, Anthony LoGalbo, Complications of Diabetes Mellitus, 2022
Jahangir Moini, Matthew Adams, Anthony LoGalbo
Prevalence calculates the actual frequency of a disease. It is the proportion of a total population with the disease. Point prevalence is the proportion of the population with the disease at one point in time. The point can be an actual date, or a specific occurrence in an individual’s life. Point prevalence is expressed as the number of existing cases, divided by the number in the total population, at a specific point in time. Therefore, the prevalence of diabetes mellitus refers to the existing cases or deaths, expressed as proportions of the population, over certain times. The amounts are divided by the number of people in the specific population, to calculate the percentages. Point prevalence refers to all cases or deaths. It is calculated by dividing the number of cases by the size of the same population, then multiplied by a certain value. If 100 is the value used to multiply, a percentage is created. So, if there were 5,000 existing cases of diabetes within a total population of 160,000, the point prevalence now the study was performed would be 3.1%.
Adult Asthma
Published in Pudupakkam K Vedanthan, Harold S Nelson, Shripad N Agashe, PA Mahesh, Rohit Katial, Textbook of Allergy for the Clinician, 2021
Flavia CL Hoyte, Eugene M Choo, Rohit K Katial
Prevalence is defined by the total number of cases of a given disease in a specific population at a specific time. Although asthma is present throughout the world, prevalence rates vary greatly, with developed countries having higher values than less affluent nations. Most recent estimates from the 2015 Global Burden of Disease study place worldwide prevalence at approximately 358.2 million people, which is approximately 12.6% higher than in 1990 (GBD 2015). Age-specific asthma prevalence estimates vary tremendously, with ranges of 3 to 38% in children and 2 to 12% in adults (Masoli et al. 2004). A 2002– 2003 World Health Survey from the World Health Organization of 177,496 adults from 70 different countries demonstrated that the prevalence of asthma varies greatly among different countries, with an approximate 21-fold difference between the lowest and highest prevalence nations. In this survey, 4.5% of these adults either carried a doctor’s diagnosis of asthma or had taken asthma medications in the past year, and approximately 8.6% stated that they had noticed wheezing in the 12 months prior to the survey. Australia, northern and western Europe and Brazil demonstrated the highest prevalence (To et al. 2012). Although the worldwide prevalence of asthma is increasing as a whole, it has stabilized or decreased in some of the highest prevalence countries, such as Australia (Poulos et al. 2005). This stabilization trend is particularly apparent in higher income countries, which may reflect improved asthma control through advanced medication and education (Dharmage et al. 2019).
Practical guide to scanning the saphenous systems (GSV and SSV) and perforators
Published in Joseph A. Zygmunt, Venous Ultrasound, 2020
A key piece of information is understanding what to expect during the exam. Therefore, as noted in the SVU's guidance above, a brief review of the patient's history, and clinical examination will assist the sonographer for correlation of diagnostic findings to clinical presentation. In this respect, understanding the prevalence of the distribution of disease can also be very helpful. As noted in three publications from 2001 to 2013, Table 6.2 shows the general anatomic distribution of reflux disease. A fourth paper, from 2017, is an outlier with respect to a “doubling” of the non-saphenous patients. A possible reason for this outlier data is the 86% prevalence of female to 14% male patients in the cohort, which may suggest a catering by this practice to women. It could also suggest an increasing knowledge of pelvic issues. In addition, in cases of great saphenous vein (GSV) incompetence, terminal valve incompetence was noted in 71% of patients [8]. In addition, there is still a prevalence of GSV reflux where a competent saphenofemoral junction (SFJ) is noted [9]. This information is primarily drawn from infra-inguinal duplex exams.
Increasing prevalence of chronic hepatitis B virus infection and low linkage to care in Denmark on 31 December 2016 – an update based on nationwide registers
Published in Infectious Diseases, 2023
Signe Bollerup, Maria Wessman, Janne Fuglsang Hansen, Stine Nielsen, Gordon Hay, Susan Cowan, Henrik Krarup, Lars Omland, Peter Jepsen, Nina Weis, Peer Brehm Christensen
Increasing prevalence could be related to several factors. As HBV vaccination is not part of the Danish childhood vaccination program, new infections due to sexual transmission, intravenous drug use, travel or other horizontal transmission in susceptible individuals could be behind the observed increase. However, acute HBV infections are rare in Denmark [19–21], and may not fully explain the observed increase in prevalence. The majority registered with chronic HBV infection had a country of origin other than Denmark. The proportion of residents that immigrated to Denmark rose from 6.6% in 2007 to 9.5% in 2016 [22]. Thus, it is likely that immigration from areas with higher prevalence of chronic HBV infection contributed to the increasing prevalence. This is in line with previous findings from Germany, where HBsAg prevalence (3.6%) among migrants was higher than in first time blood donors, pregnant women and people who injected drugs [23]. Nonetheless, the low but increasing prevalence of HBV supports that HBV childhood vaccination should be considered in Denmark.
Prevalence and related factors of hyperuricaemia in Chinese children and adolescents: a pooled analysis of 11 population-based studies
Published in Annals of Medicine, 2022
Jiahuan Rao, Peiyu Ye, Jie Lu, Bi Chen, Nan Li, Huiying Zhang, Hui Bo, Xinchun Chen, Huiting Liu, Chunhong Zhang, Hua Wei, Qin Wu, Yinkun Yan, Changgui Li, Jie Mi
With the rapid socio-economic development of China in recent decades, purine-abundant diets and physical inactivity have become increasingly common [6,7], which may lead to increasing prevalence of hyperuricaemia [8]. A meta-analysis of adults showed that the prevalence of hyperuricaemia was 13.3% in mainland China during 2000–2014 [9]. However, the prevalence of hyperuricaemia among Chinese children and adolescents is poorly characterized. Previous cross-sectional studies have demonstrated that the prevalence of hyperuricaemia in Chinese youths varied across surveys ranging from 10.1 to 25.4% [10–19], and most of these studies are limited to certain area, small sample size, specific age period or inconsistent diagnostic criteria. Therefore, it is particularly important to obtain national prevalence and related factors, which can help to improve health awareness and formulate appropriate public health policies. In this study, we aimed to estimate the prevalence of hyperuricaemia and identify its related factors in Chinese children and adolescents during 2009–2019 using pooled sample from 11 population-based studies.
Rarely mentioned: how we arrived at the quantitative definition of a rare disease
Published in Baylor University Medical Center Proceedings, 2022
Systematizing the definition of rare disease and recognizing the persistence of prevalence go hand in hand. Richter recommended that “any attempt to harmonize rare disease definitions should focus on standardizing objective criteria such as prevalence thresholds.” In his study, “172 of 296 definitions (58%) included a prevalence threshold,” and that prompted him to conclude that “it appears that prevalence is the universally preferred epidemiology metric used in definitions of rare disease.” He added, moreover, that “prevalence rather than incidence is the most appropriate metric because this reflects how widespread a disease is (as opposed to reflecting the rate of occurrence) and is amenable to use for specific subpopulations. More importantly, the use of prevalence facilitates international comparisons.”3 For clarity, recall that incidence implies the frequency of a disease in a population, and typically the measurement is the number of new cases over a defined period. Prevalence refers to the percentage of the population harboring the affliction in question at a given moment or specified time frame (Table 1).