Adult attention-deficit hyperactivity disorder (ADHD) has recently attracted much attention, however, an up-to-date estimation on the prevalence of adult ADHD is lacking. In this study, we aimed to assess the global prevalence of adult ADHD in the general population through a systematic review and meta-analysis. PubMed, Medline, Embase and PsycINFO were searched to identify relevant articles published from January 2000 onwards. Population-based studies that were conducted in the general adult population and quantified the prevalence of adult ADHD were included. The prevalence of persistent adult ADHD (with a childhood onset) and symptomatic adult ADHD (regardless of a childhood onset) both decreased with advancing age. By adjusting for the global demographic structure in 2020, the prevalence of persistent adult ADHD was 2.58% and that of symptomatic adult ADHD was 6.76%, translating to 139.84 million and 366.33 million affected adults in 2020 globally. This study provides an up-to-date estimation of the global prevalence of both persistent and symptomatic adult ADHD. A well-defined strategy for diagnosing adult ADHD and large-scale investigations on the epidemiology of adult ADHD are needed.

Objective This study aimed to explore the global burden of early-onset cancer based on the Global Burden of Disease (GBD) 2019 study for 29 cancers worldwid. Methods and analysis Incidence, deaths, disability-adjusted life years (DALYs) and risk factors for 29 early-onset cancer groups were obtained from GBD. Results Global incidence of early-onset cancer increased by 79.1% and the number of early-onset cancer deaths increased by 27.7% between 1990 and 2019. Early-onset breast, tracheal, bronchus and lung, stomach and colorectal cancers showed the highest mortality and DALYs in 2019. Globally, the incidence rates of early-onset nasopharyngeal and prostate cancer showed the fastest increasing trend, whereas early-onset liver cancer showed the sharpest decrease. Early-onset colorectal cancers had high DALYs within the top five ranking for both men and women. High-middle and middle Sociodemographic Index (SDI) regions had the highest burden of early-onset cancer. The morbidity of early-onset cancer increased with the SDI, and the mortality rate decreased considerably when SDI increased from 0.7 to 1. The projections indicated that the global number of incidence and deaths of early-onset cancer would increase by 31% and 21% in 2030, respectively. Dietary risk factors (diet high in red meat, low in fruits, high in sodium and low in milk, etc), alcohol consumption and tobacco use are the main risk factors underlying early-onset cancers. Conclusion Early-onset cancer morbidity continues to increase worldwide with notable variances in mortality and DALYs between areas, countries, sex and cancer types. Encouraging a healthy lifestyle could reduce early-onset cancer disease burden.

Objective: To estimate the global and regional prevalence and cases of abdominal aortic aneurysms (AAAs) in 2019 and to evaluate major associated factors. Background: Understanding the global prevalence of AAA is essential for optimizing health services and reducing mortality from reputed AAA. Methods: PubMed, MEDLINE, and Embase were searched for articles published until October 11, 2021. Population-based studies that reported AAA prevalence in the general population, defined AAA as an aortic diameter of 30 mm or greater with ultrasonography or computed tomography. A multilevel mixed-effects meta-regression approach was used to establish the relation between age and AAA prevalence for high-demographic sociodemographic index and low-and middle-sociodemographic index countries. Odds ratios of AAA associated factors were pooled using a random-effects method. Results: We retained 54 articles across 19 countries. The global prevalence of AAA among persons aged 30 to 79 years was 0.92% (95% CI, 0.65–1.30), translating to a total of 35.12 million (95% CI, 24.94–49.80) AAA cases in 2019. Smoking, male sex, family history of AAA, advanced age, hypertension, hypercholesterolemia, obesity, cardiovascular disease, cerebrovascular disease, claudication, peripheral artery disease, pulmonary disease, and renal disease were associated with AAA. In 2019, the Western Pacific region had the highest AAA prevalence at 1.31% (95% CI, 0.94–1.85), whereas the African region had the lowest prevalence at 0.33% (95% CI, 0.23–0.48). Conclusions: A substantial proportion of people are affected by AAA. There is a need to optimize epidemiological studies to promptly respond to at-risk and identified cases to improve outcomes.

Stroke remains a significant global health challenge, with persistent disparities in burden across different countries and regions. This study aimed to assess the temporal trends in cross-country inequalities of stroke and its subtypes burden from 1990 to 2021. We conducted a secondary analysis of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021. The age-standardised disability-adjusted life years (DALYs) rate (ASDR) was used to assess the burden of stroke and its subtypes (ischemic stroke, intracerebral haemorrhage, and subarachnoid haemorrhage) across 21 GBD regions and 204 countries. The slope index of inequality (SII) and the concentration index were calculated to quantify the absolute and relative cross-country inequalities in the burden of stroke and its subtypes, with negative values indicating a higher burden in lower socio-demographic index (SDI) countries, and positive values indicating a higher burden in higher SDI countries. Estimated annual percentage change (EAPC) was used to illustrate temporal trends at global and regional levels from 1990 to 2021. The inequality changing patterns from 1990 to 2021 were classified as worsening, improving, and shifting to higher burdens among higher or lower SDI countries. From 1990 to 2021, the ASDR of total stroke decreased from 3078.95 (95% uncertainty interval [UI]: 2893.58, 3237.34) to 1886.20 (95% UI: 1738.99, 2017.90) per 100,000 population globally. While both absolute and relative inequalities increased, with a disproportionately higher burden shouldered by countries with lower SDI. The SII of total stroke exhibited a worsening inequality among lower SDI countries, increasing by 286.97 units from −2329.47 (95% confidence interval [CI]: −2857.50, −1801.43) in 1990 to −2616.44 (95% CI: −2987.33, −2245.56) in 2021. Similarly, the concentration index of total stroke increased by 0.03 from −0.0819 (95% CI: −0.1143, −0.0495) in 1990 to −0.1119 (95% CI: −0.1478, −0.0759) in 2021. The changing patterns from 1990 to 2021 were diverse across regions, yet most regions exhibited a worsening inequality among lower SDI countries in both SII and concentration index. Southern Sub-Saharan Africa showed the largest worsening inequality in SII (EAPC: −2.15, 95% CI: −2.71, −1.57) while Central Europe showed the largest worsening inequality in concentration index (EAPC: −0.51, 95% CI: −0.58, −0.44). In 2021, the highest negative SII was observed in Oceania and the highest negative concentration index was in the Caribbean. In terms of subtypes, ischemic stroke reported a worsening inequality among lower SDI countries in SII (EAPC: −2.13, 95% CI: −2.20, −2.05) while intracerebral haemorrhage showed an improving inequality in SII (EAPC: 0.44, 95% CI: 0.40, 0.47). SII in subarachnoid haemorrhage (EAPC: −0.18, 95% CI: −0.19, −0.17) and concentration index in ischemic stroke (EAPC: −0.25, 95% CI: −0.27, −0.23) presented a shift to higher burden among lower SDI countries from 1990 to 2021. Although the burden of stroke and its subtypes decreased from 1990 to 2021, inequalities have persisted and even widened in some regions. Timely and effective prevention and management strategies for stroke and its subtypes are needed in specific areas to reduce the stroke burden and achieve equity in health outcomes. None.

Trimethylamine-N-oxide (TMAO) is a gut microbiota–derived metabolite produced from dietary nutrients. Many studies have discovered that circulating TMAO concentrations are linked to a wide range of health outcomes. This study aimed to summarize health outcomes related to circulating TMAO concentrations. We searched the Embase, Medline, Web of Science, and Scopus databases from inception to 15 February, 2022 to identify and update meta-analyses examining the associations between TMAO and multiple health outcomes. For each health outcome, we estimated the summary effect size, 95% prediction CI, between-study heterogeneity, evidence of small-study effects, and evidence of excess-significance bias. These metrics were used to evaluate the evidence credibility of the identified associations. This umbrella review identified 24 meta-analyses that investigated the association between circulating TMAO concentrations and health outcomes including all-cause mortality, cardiovascular diseases (CVDs), diabetes mellitus (DM), cancer, and renal function. We updated these meta-analyses by including a total of 82 individual studies on 18 unique health outcomes. Among them, 14 associations were nominally significant. After evidence credibility assessment, we found 6 (33%) associations (i.e., all-cause mortality, CVD mortality, major adverse cardiovascular events, hypertension, DM, and glomerular filtration rate) to present highly suggestive evidence. TMAO might be a novel biomarker related to human health conditions including all-cause mortality, hypertension, CVD, DM, cancer, and kidney function. Further studies are needed to investigate whether circulating TMAO concentrations could be an intervention target for chronic disease. This review was registered at www.crd.york.ac.uk/prospero/ as CRD42021284730.