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Diagnosing heart failure (HF) in primary care can be challenging, especially
in elderly patients with comorbidities. Insight in the prevalence, age,
comorbidity and routine practice of diagnosing HF in general practice may
improve the process of diagnosing HF.
To examine the prevalence of HF in relation to ageing and comorbidities, and
routine practice of diagnosing HF in general practice.
A retrospective cohort study was performed using data from electronic health
records of 56 320 adult patients of 11 general practices. HF patients were
compared with patients without HF using descriptive analyses and
χ2 tests. The following comorbidities were considered: chronic
obstructive pulmonary disorder (COPD), diabetes mellitus (DM), hypertension,
anaemia and renal function disorder (RFD). Separate analyses were performed
for men and women.
The point prevalence of HF was 1.2% (95% confidence interval
1.13–1.33) and increased with each age category from 0.04%
(18–44 years) to 20.9% (⩾85 years). All studied
comorbidities were significantly (P<0.001) more
common in HF patients than in patients without HF: COPD (24.1% versus
3.1%), DM (34.7% versus 6.5%), hypertension
(52.7% versus 16.0%), anaemia (10.9% versus
2.3%) and RFD (61.8% versus 7.5%). N-terminal pro-BNP
(NT-proBNP) was recorded in 38.1% of HF patients.
HF is highly associated with ageing and comorbidities. Diagnostic use of
NT-proBNP in routine primary care seems underutilized. Instruction of GPs to
determine NT-proBNP in patients suspected of HF is recommended, especially
In elderly patients with comorbidities.
The epidemiology of heritable traits whose prevalence is determined by a balance between mutation and selection is often explored through deterministic models. Here, the properties are explored by simulation of a model population followed through a sequence of closely spaced time points. Mutation and birth and death occur randomly. The condition neurofibromatosis type 1 (NF1) is used as a point of reference. Critical parameters, such as mutation rates and selection forces, are not known precisely for NF1 so speculative values based on published data from Finland and other studies are proposed.
Personality disorders are now internationally recognised as a mental health priority. Nevertheless, there are no systematic reviews examining the global prevalence of personality disorders.
To calculate the worldwide prevalence of personality disorders and examine whether rates vary between high-income countries and low- and middle-income countries (LMICs).
We systematically searched PsycINFO, MEDLINE, EMBASE and PubMed from January 1980 to May 2018 to identify articles reporting personality disorder prevalence rates in community populations (PROSPERO registration number: CRD42017065094).
A total of 46 studies (from 21 different countries spanning 6 continents) satisfied inclusion criteria. The worldwide pooled prevalence of any personality disorder was 7.8% (95% CI 6.1–9.5). Rates were greater in high-income countries (9.6%, 95% CI 7.9–11.3%) compared with LMICs (4.3%, 95% CI 2.6–6.1%). In univariate meta-regressions, significant heterogeneity was partly attributable to study design (two-stage v. one-stage assessment), county income (high-income countries v. LMICs) and interview administration (clinician v. trained graduate). In multiple meta-regression analysis, study design remained a significant predictor of heterogeneity. Global rates of cluster A, B and C personality disorders were 3.8% (95% CI 3.2, 4.4%), 2.8% (1.6, 3.7%) and 5.0% (4.2, 5.9%).
Personality disorders are prevalent globally. Nevertheless, pooled prevalence rates should be interpreted with caution due to high levels of heterogeneity. More large-scale studies with standardised methodologies are now needed to increase our understanding of population needs and regional variations.
Infertility is generally defined as the inability to establish a clinical pregnancy after 12 months of regular, unprotected sexual intercourse. Estimates of the prevalence of infertility are variable due to differing methodological approaches. In vitro fertilization (IVF) methods were first developed in animals; however, their potential for overcoming infertility in humans was quickly recognized. The first infant conceived using assisted reproductive technology (ART) was born in 1978 in the United Kingdom. ART techniques have improved over time and use of ART has increased substantially, although use of ART varies across regions, countries, and jurisdictions. Availability of ART services may be affected by legal restrictions and guidelines. Insurance coverage for ART differs across countries; lack of reimbursement for fertility treatment costs is often barrier to accessing to ART.
Peripheral low-grade inflammation in depression is increasingly seen as a therapeutic target. We aimed to establish the prevalence of low-grade inflammation in depression, using different C-reactive protein (CRP) levels, through a systematic literature review and meta-analysis.
We searched the PubMed database from its inception to July 2018, and selected studies that assessed depression using a validated tool/scale, and allowed the calculation of the proportion of patients with low-grade inflammation (CRP >3 mg/L) or elevated CRP (>1 mg/L).
After quality assessment, 37 studies comprising 13 541 depressed patients and 155 728 controls were included. Based on the meta-analysis of 30 studies, the prevalence of low-grade inflammation (CRP >3 mg/L) in depression was 27% (95% CI 21–34%); this prevalence was not associated with sample source (inpatient, outpatient or population-based), antidepressant treatment, participant age, BMI or ethnicity. Based on the meta-analysis of 17 studies of depression and matched healthy controls, the odds ratio for low-grade inflammation in depression was 1.46 (95% CI 1.22–1.75). The prevalence of elevated CRP (>1 mg/L) in depression was 58% (95% CI 47–69%), and the meta-analytic odds ratio for elevated CRP in depression compared with controls was 1.47 (95% CI 1.18–1.82).
About a quarter of patients with depression show evidence of low-grade inflammation, and over half of patients show mildly elevated CRP levels. There are significant differences in the prevalence of low-grade inflammation between patients and matched healthy controls. These findings suggest that inflammation could be relevant to a large number of patients with depression.
Posttraumatic stress disorder (PTSD) is a psychological disorder, which could be caused by traumatic events. The prevalence of PTSD among survivors after a typhoon or hurricane varied widely. Therefore, this study aimed to determine a combined prevalence of PTSD among survivors after a typhoon or hurricane. A systematic search of literature was performed in the 3 English databases: PubMed (National Library of Medicine, Bethesda, MD), ISI Web of Science (Thomson Reuters, New York, NY), and Embase (Elsevier, Amsterdam, Netherlands). Also, a similar search was performed in the 2 Chinese databases such as Chinese National Knowledge Infrastructure and WanFang. Loney et al.’s criteria were used to evaluate the quality of the selected articles for this study. The combined prevalence of PTSD among the study population was estimated using the Freeman–Tukey double arcsine transformation method. Subgroup analyses and a meta-regression analysis were carried out to explore the origin of heterogeneity. Thirty-nine eligible articles were included in this study. They comprised 43 123 typhoon and hurricane survivors of which 9373 were diagnosed with PTSD. The combined prevalence of PTSD among this population was 17.81%. Subgroup analyses revealed that the combined prevalence of PTSD related to typhoon and hurricane Categories 5, 4, and 2 showing a corresponding decreasing tendency. About 18% of people who experienced a severe typhoon or hurricane develop PTSD with the prevalence decreasing with reduced severity of the typhoon or hurricane.
Seroprevalence estimation using cross-sectional serosurveys can be challenging due to inadequate or unknown biological cut-off limits of detection. In recent years, diagnostic assay cut-offs, fixed assay cut-offs and more flexible approaches as mixture modelling have been proposed to classify biological quantitative measurements into a positive or negative status. Our objective was to estimate the prevalence of anti-HCV antibodies among drug users (DU) in France in 2011 using a biological test performed on dried blood spots (DBS) collected during a cross-sectional serosurvey. However, in 2011, we did not have a cut-off value for DBS. We could not use the values for serum or plasma, knowing that the DBS value was not necessarily the same. Accordingly, we used a method which consisted of applying a two-component mixture model with age-dependent mixing proportions using penalised splines. The component densities were assumed to be log-normally distributed and were estimated in a Bayesian framework. Anti-HCV prevalence among DU was estimated at 43.3% in France and increased with age. Our method allowed us to provide estimates of age-dependent prevalence using DBS without having a specified biological cut-off value.
For parasites in natural systems, the most common pattern of spatial distribution is aggregation among hosts. The main causes of such aggregation are variable exposure of hosts to parasites and heterogeneity in host susceptibility. The objective of this study was to determine if there are differences in the aggregation pattern of two species of ectoparasitic flies between the Pantanal and Cerrado regions of Brazil on the bat Artibeus planirostris. We collected the ectoparasites from bats captured between 2002 and 2017 with mist nets in 21 sites in the Pantanal and 15 sites in the surrounding plateaus. The results showed that the aggregation of ectoparasitic flies in Pantanal was more pronounced than in Cerrado. The discrepancy aggregation index (D) of the bat fly Megistopoda aranea was 0.877 in Pantanal and 0.724 in Cerrado. The D values of Aspidoptera phyllostomatis was even higher, with 0.916 and 0.848 in the Pantanal and Cerrado, respectively. Differences in the shelters used may be the main factor shaping variation in aggregation, since the Pantanal does not have rock formations, with only foliage, crowns and hollow tree trunks. These differences likely affect host exposure to the parasites, leading to an increase in parasite aggregation.
To estimate the lifetime prevalence and potential determinants of psychotic experience(s) (PEs) in the general population of Qatar – a small non-war afflicted, conservative, high-income, middle-eastern country with recent rapid urbanization including an influx of migrants.
A probability-based sample (n = 1353) of non-migrants and migrants were interviewed face-to-face and administered a 7-item psychosis screener adapted from the Composite International Diagnostic Interview, the Kessler 6-item psychological distress scale, and the 5 items assessing odd (paranormal) beliefs and magical thinking (OBMT) from the Schizotypal Personality Questionnaire. Using bivariate and logistic regression analyses, lifetime prevalence rates of PEs were estimated then compared before and after adjustment for socio-demographics, Arab ethnicity, psychological distress, and OBMT.
Prevalence of PEs was 27.9%. Visual hallucinations were most common (12.8%), followed by persecutory delusions (6.7%) and auditory hallucinations (6.9%). Ideas of reference (3.6%) were least prevalent. PEs were significantly higher in Arabs (34.7%) compared with non-Arabs (16.4%, p < 0.001) with the exception of ideas of reference and paranoid delusions. Female gender was associated with a higher prevalence of PEs in the Arab group only (p < 0.001). Prevalence of PEs was significantly higher among Arabs (48.8% v. 15.8%, p < 0.001) and non-Arabs (35.2% v. 7.3%, p < 0.001) with OBMT. Arab ethnicity (OR = 2.10, p = 0.015), psychological distress (OR = 2.29 p = 0.003), and OBMT (OR = 6.25, p < 0.001) were independently associated with PEs after adjustment for all variables.
Ethnicity, but not migration was independently associated with PEs. Evidence linking Arab ethnicity, female gender, and psychological distress to PEs through associations with OBMT was identified for future prospective investigations.
Bipolar disorder (BD) and obsessive compulsive disorder (OCD) are prevalent, comorbid, and disabling conditions, often characterized by early onset and chronic course. When comorbid, OCD and BD can determine a more pernicious course of illness, posing therapeutic challenges for clinicians. Available reports on prevalence and clinical characteristics of comorbidity between BD and OCD showed mixed results, likely depending on the primary diagnosis of analyzed samples.
We assessed prevalence and clinical characteristics of BD comorbidity in a large international sample of patients with primary OCD (n = 401), through the International College of Obsessive–Compulsive Spectrum Disorders (ICOCS) snapshot database, by comparing OCD subjects with vs without BD comorbidity.
Among primary OCD patients, 6.2% showed comorbidity with BD. OCD patients with vs without BD comorbidity more frequently had a previous hospitalization (p < 0.001) and current augmentation therapies (p < 0.001). They also showed greater severity of OCD (p < 0.001), as measured by the Yale–Brown Obsessive Compulsive Scale (Y-BOCS).
These findings from a large international sample indicate that approximately 1 out of 16 patients with primary OCD may additionally have BD comorbidity along with other specific clinical characteristics, including more frequent previous hospitalizations, more complex therapeutic regimens, and a greater severity of OCD. Prospective international studies are needed to confirm our findings.
Little information is available on the prevalence of Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 eating disorders in adolescence, and eating disorders remain unique in the DSM for not systematically including a criterion for clinical significance. This study aimed to provide the first prevalence report of the full suite of DSM-5 eating disorders in adolescence, and to examine the impact of applying a criterion for clinical significance.
In total, 5191 (participation rate: 70%) Australian adolescents completed a survey measuring 1-month prevalence of eating disorder symptoms for all criterial, ‘other specified’ and unspecified eating disorders, as well as health-related quality of life and psychological distress.
The point prevalence of any eating disorder was 22.2% (12.8% in boys, 32.9% in girls), and ‘other specified’ disorders (11.2%) were more common than full criterial disorders (6.2%). Probable bulimia nervosa and binge eating disorder, but not anorexia nervosa (AN), were more likely to be experienced by older adolescents. Most disorders were associated with an increased odds for being at a higher weight. The prevalence of eating disorders was reduced by 40% (to 13.6%) when a criterion for clinical significance was applied.
Eating disorders, particularly ‘other specified’ syndromes, are common in adolescence, and are experienced across age, weight, socioeconomic and migrant status. The merit of adding a criterion for clinical significance to the eating disorders, similar to other DSM-5 disorders, warrants consideration. At the least, screening tools should measure distress and impairment associated with eating disorder symptoms in order to capture adolescents in greatest need for intervention.
Although sleep apnea is an important disorder associated with cardiac events, data regarding its prevalence and risk factors in adult patients with congenital heart disease are limited.
In this study, patients underwent a sleep study in the hospital. Indications for admission were classified as heart failure, diagnostic catheterisation, interventional catheterisation, or arrhythmia. The prevalence, characteristics, and risk factors of sleep apnea using a type-3 portable overnight polygraph in adult patients with congenital heart disease were evaluated.
There were 104 patients [median age: 36 (interquartile range: 28–48) years] who were admitted for heart failure 34% (n = 36), diagnostic catheterisation 26% (n = 27), interventional catheterisation 18% (n = 19), or arrhythmia 22% (n = 23). The prevalence of sleep apnea, defined as a respiratory disturbance index ≥5, was 63% (n = 63), with a distribution of 37%, 16%, and 10% for mild (5≤ respiratory disturbance index <15), moderate (15≤ respiratory disturbance index <30), and severe (respiratory disturbance index ≥30) sleep apnea, respectively. A large majority of the sleep apnea cases were categorised as obstructive sleep apnea (92%, n = 58). The respiratory disturbance index ≥15 group had a significantly higher proportion of male patients and higher body mass index, noradrenaline level, and aortic blood pressure than the group without sleep apnea (respiratory disturbance index <5). Multivariable analysis showed that New York Heart Association class ≥II (OR, 4.36; 95% CI, 1.09–20.87) and body mass index ≥25 (OR, 4.29; 95% CI, 1.32–15.23) were independent risk factors for a respiratory disturbance index ≥15.
Our results showed a high prevalence of sleep apnea in adult patients with congenital heart disease. Its unique haemodynamics may be associated with a high prevalence of sleep apnea. Congestive heart failure and being overweight are important risk factors for sleep apnea. Management of heart failure and general lifestyle improvements will be important for controlling sleep apnea symptoms in these patients.
Research indicates that anti-depressant prescribing is higher in Northern Ireland (NI) than in the rest of the UK, and that socio-economic and area-level factors may contribute to this. The current study provides comprehensive population-based estimates of the prevalence of anti-depressant prescription prescribing in NI from 2011 to 2015, and examined the associations between socio-demographic, socio-economic, self-reported health and area-level factors and anti-depressant prescription.
Data were derived from the 2011 NI Census (N = 1 588 355) and the Enhanced Prescribing Database. Data linkage techniques were utilised through the Administrative Data Research Centre in NI. Prevalence rates were calculated and binary logistic analysis assessed the associations between contextual factors and anti-depressant prescription.
From 2011 to 2015, the percentages of the population in NI aged 16 or more receiving anti-depressant prescriptions were 12.3%, 12.9%, 13.4%, 13.9% and 14.3%, respectively, and over the 5-year period was 24.3%. The strongest predictors of anti-depressant prescription in the multivariate model specified were ‘very bad’ (OR = 4.02) or ‘Bad’ general health (OR = 3.98), and self-reported mental health problems (OR = 3.57). Other significant predictors included social renting (OR = 1.67) and unemployment (OR = 1.25). Protective factors included Catholic religious beliefs, other faith/philosophic beliefs and no faith/philosophic beliefs in comparison to reporting Protestant/other Christian religious beliefs (ORs = 0.78–0.91).
The prevalence of anti-depressant prescription in NI appears to be higher than the prevalence of depressive disorders, although this may not necessarily be attributable to over-prescribing as anti-depressants are also prescribed for conditions other than depression. Anti-depressant prescription was linked to several factors that represent socio-economic disadvantage.
Climate and weather conditions may have substantial effects on the ecology of both parasites and hosts in natural populations. The strength and shape of the effects of weather on parasites and hosts are likely to change as global warming affects local climate. These changes may in turn alter fundamental elements of parasite–host dynamics. We explored the influence of temperature and precipitation on parasite prevalence in a metapopulation of avian hosts in northern Norway. We also investigated if annual change in parasite prevalence was related to winter climate, as described by the North Atlantic Oscillation (NAO). We found that parasite prevalence increased with temperature within-years and decreased slightly with increasing precipitation. We also found that a mild winter (positive winter NAO index) was associated with higher mean parasite prevalence the following year. Our results indicate that both local and large scale weather conditions may affect the proportion of hosts that become infected by parasites in natural populations. Understanding the effect of climate and weather on parasite–host relationships in natural populations is vital in order to predict the full consequence of global warming.
The second Singapore Mental Health Study (SMHS) – a nationwide, cross-sectional, epidemiological survey - was initiated in 2016 with the intent of tracking the state of mental health of the general population in Singapore. The study employed the same methodology as the first survey initiated in 2010. The SMHS 2016 aimed to (i) establish the 12-month and lifetime prevalence and correlates of major depressive disorder (MDD), dysthymia, bipolar disorder, generalised anxiety disorder (GAD), obsessive compulsive disorder (OCD) and alcohol use disorder (AUD) (which included alcohol abuse and dependence) and (ii) compare the prevalence of these disorders with reference to data from the SMHS 2010.
Door-to-door household surveys were conducted with adult Singapore residents aged 18 years and above from 2016 to 2018 (n = 6126) which yielded a response rate of 69.0%. The subjects were randomly selected using a disproportionate stratified sampling method and assessed using World Health Organization Composite International Diagnostic Interview version 3.0 (WHO-CIDI 3.0). The diagnoses of lifetime and 12-month selected mental disorders including MDD, dysthymia, bipolar disorder, GAD, OCD, and AUD (alcohol abuse and alcohol dependence), were based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria.
The lifetime prevalence of at least one mood, anxiety or alcohol use disorder was 13.9% in the adult population. MDD had the highest lifetime prevalence (6.3%) followed by alcohol abuse (4.1%). The 12-month prevalence of any DSM-IV mental disorders was 6.5%. OCD had the highest 12-month prevalence (2.9%) followed by MDD (2.3%). Lifetime and 12-month prevalence of mental disorders assessed in SMHS 2016 (13.8% and 6.4%) was significantly higher than that in SMHS 2010 (12.0% and 4.4%). A significant increase was observed in the prevalence of lifetime GAD (0.9% to 1.6%) and alcohol abuse (3.1% to 4.1%). The 12-month prevalence of GAD (0.8% vs. 0.4%) and OCD (2.9% vs. 1.1%) was significantly higher in SMHS 2016 as compared to SMHS 2010.
The high prevalence of OCD and the increase across the two surveys needs to be tackled at a population level both in terms of creating awareness of the disorder and the need for early treatment. Youth emerge as a vulnerable group who are more likely to be associated with mental disorders and thus targeted interventions in this group with a focus on youth friendly and accessible care centres may lead to earlier detection and treatment of mental disorders.
Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are usually asymptomatic for decades, thus targeted screening can prevent liver disease by timely diagnosis and linkage to care. More robust estimates of chronic HBV and HCV infections in the general population and risk groups are needed. Using a modified workbook method, the total number of ever chronically infected individuals in the Netherlands in 2016 was determined using population size and prevalence estimates from studies in the general and high-risk population. The estimated 2016 chronic HBV infection prevalence is 0.34% (low 0.22%, high 0.47%), corresponding to approximately 49 000 (low 31 000, high 66 000) HBV-infected individuals aged 15 years and older. The estimated ever-chronic HCV infection prevalence is 0.16% (low 0.06%, high 0.27%), corresponding to approximately 23 000 (low 8000, high 38 000) ever-chronic HCV-infected individuals. The prevalence of chronic HBV and HCV infections in the Netherlands is low. First-generation migrants account for most infections with 81% and 60% of chronic HBV and HCV infections, respectively. However, about one-fifth of HCV infections is found in the general population at low risk. This method can serve as an example for countries in need of more accurate prevalence estimates, to help the design and evaluation of prevention and control policies.
Clozapine treatment increases the risk of agranulocytosis, but findings on the epidemiology of agranulocytosis have been inconsistent. This meta-analysis examined the prevalence of agranulocytosis and related death in clozapine-treated patients.
A literature search in the international (PubMed, PsycINFO, and EMBASE) and Chinese (WanFang, Chinese National Knowledge Infrastructure, and Sinomed) databases was conducted. Prevalence estimates of agranulocytosis and related death in clozapine-treated patients were synthesized with the Comprehensive Meta-Analysis program using the random-effects model.
Thirty-six studies with 260 948 clozapine-treated patients published between 1984 and 2018 were included in the meta-analysis. The overall prevalence of agranulocytosis and death caused by agranulocytosis were 0.4% (95% CI 0.3–0.6%) and 0.05% (95% CI 0.03–0.09%), respectively. The prevalence of agranulocytosis was moderated by sample size, study quality, year of publication, and that of data collection.
The prevalence of clozapine-associated agranulocytosis is low. Agranulocytosis-related death appears rare.