There have been mixed results regarding the relationship among short chain fatty acids (SCFAs), microbiota, and obesity in human studies. We selected studies that provided data on SCFA levels or fecal microbiota abundance in obese and nonobese individuals and then combined the published estimates using a random-effects meta-analysis. Obese individuals had significantly higher fecal concentrations of acetate (SMD (standardized mean differences) = 0.87, 95% CI (confidence interva) = 0.24–1.50, I² (I–squared) = 88.5), propionate (SMD = 0.86, 95% CI = 0.35–1.36, I² = 82.3%), and butyrate (SMD = 0.78, 95% CI = 0.29–1.27, I² = 81.7%) than nonobese controls. The subgroup analyses showed no evidence of heterogeneity among obese individuals with a BMI >30 kg/m² (I² = 0.0%). At the phylum level, the abundance of fecal microbiota was reduced in obese compared to nonobese individuals, but the difference was not statistically significant (Bacteroidetes phylum, SMD = −0.36, 95% CI = −0.73–0.01; Firmicutes phylum, SMD = −0.10, 95% CI = −0.31–0.10). The currently available human case-control studies show that obesity is associated with high levels of SCFA but not gut microbiota richness at the phylum level. Additional well-designed studies with a considerable sample size are needed to clarify whether this association is causal, but it is also necessary to identify additional contributors to SCFA production, absorption, and excretion in humans.

Older people are more likely to be excluded from the digital world, and this has been linked to poor health outcomes. The extent and direction of the influence of digital exclusion on functional dependency is, however, not well understood. We aimed to investigate the association between digital exclusion and functional dependency among older adults from high-income countries (HICs) and low- and middle-income countries (LMICs). In this multicohort study, we pooled individual-level data from five longitudinal cohort studies that included nationally representative samples of older adults across 23 countries, including the Health and Retirement Study (HRS), the English Longitudinal Study of Aging (ELSA), the Survey of Health, Ageing and Retirement in Europe (SHARE), the China Health and Retirement Longitudinal Study (CHARLS), and the Mexican Health and Aging Study (MHAS). The digital exclusion was recorded as an absence from internet use by self-reported. We assessed basic activities of daily living (BADL) and instrumental activities of daily living (IADL), and we used interval-of-need methods to categorize the functional dependency. We applied generalized estimating equations models fitting Poisson model to investigate the association of digital exclusion with difficulties in BADL or IADL and functional dependency, adjusting for the causal-directed-acyclic-graph (DAG) minimal sufficient adjustment set (MSAS), including gender, age level, labour force status, education, household wealth level, marital status, and co-residence with children. We included 108,621 participants recruited between 2010 and 2018 with a median follow-up of 3 phrases. Digital exclusion in older adults varied across countries, ranging from 23.8% in Denmark (SHARE) to 96.9% in China (CHARLS). According to the crude model, digital exclusion was significantly associated with functional dependency. In the MSAS-adjusted model, those associations remained statistically significant: HRS (incidence rate ratio [IRR] = 1.40, 95% confidence interval [CI] 1.34–1.48 for BADL; 1.71 [1.61–1.82] for IADL), ELSA (1.31 [1.22–1.40] in BADL and 1.37 [1.28–1.46] in IADL), SHARE (1.69 [1.61–1.78] in BADL and 1.70 [1.63–1.78] in IADL), CHARLS (2.15 [1.73–2.67] in BADL and 2.59 [2.06–3.25] in IADL), and MHAS (1.15 [1.09–1.21] in BADL and 1.17 [1.09–1.25] in IADL). In the subgroup analyses, the associations were more pronounced in the oldest-old (aged ≥ 80 years old). There is a substantial proportion of older adults who are excluded from the Internet, especially those in LMIC. Older people excluded from the Internet regardless of whether they live in HICs or LMICs are more likely to develop functional dependency. It should be made a priority to remove barriers to Internet access in order to assist older people in maintaining their independence and, consequently, to reduce the care burden associated with the ageing population worldwide. The National Natural Science Foundation of China (No. 71904004).

Background: The Pittsburgh Sleep Quality Index (PSQI) is a widely used self-report questionnaire that measures general sleep quality in general populations. However, its psychometric properties have yet to be thoroughly examined in longevous persons. Objectives: This study aimed to explore the reliability, validity and factor structure of the Chinese-language version of the PSQI in community-dwelling centenarians. Methods: A total of 958 centenarians (mean age = 102.8 years; 81.8% females) recruited from 18 regions in Hainan, China, completed the PSQI scale. Cronbach’s alpha coefficient was used to measure the internal consistency. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were performed to explore the validity and factor structure of the PSQI in this sample. Correlations between the global PSQI score and physical function, depression symptoms, self-reported health status and subjective well-being were used to assess divergent validity. Results: The Cronbach’s α coefficient of the PSQI was 0.68, and it increased to 0.78 after two components (medication use and daytime dysfunction) were removed. The Spearman correlation coefficients of the PSQI score with each component were statistically significant (P<0.01). EFA yielded a two-factor structure model of the original PSQI-7 and a one-factor structure model of the simplified PSQI-5. The one-factor model with five components (χ²/df =1.59, CFI=0.99, RMSEA=0.03) fit the data well and had good configural invariance across demographic characteristics (0.53<_Δχ²0.05). Conclusions: The original PSQI showed acceptable applicability in Chinese community-dwelling centenarians, and its psychometric characteristics moderately improved after sleeping medication and daytime dysfunction were removed. Further validation studies on PSQI are needed among centenarians from varied backgrounds.

Due to the continued high incidence and mortality rate worldwide, there is still a need to develop new strategies for the prevention, diagnosis and treatment of cardiovascular diseases (CVDs). Proper cardiovascular function depends on the coordinated interplay and communication between cardiomyocytes and noncardiomyocytes. Extracellular vesicles (EVs) are enclosed in a lipid bilayer and represent a significant mechanism for intracellular communication. By containing and transporting various bioactive molecules, such as micro-ribonucleic acids (miRs) and proteins, to target cells, EVs impart favourable, neutral or detrimental effects on recipient cells, such as modulating gene expression, influencing cell phenotype, affecting molecular pathways and mediating biological behaviours. EVs can be released by cardiovascular system-related cells, such as cardiomyocytes, endotheliocytes, fibroblasts, platelets, smooth muscle cells, leucocytes, monocytes and macrophages. EVs containing miRs and proteins regulate a multitude of diverse functions in target cells, maintaining cardiovascular balance and health or inducing pathological changes in CVDs. On the one hand, miRs and proteins transferred by EVs play biological roles in maintaining normal cardiac structure and function under physiological conditions. On the other hand, EVs change the composition of their miR and protein cargoes under pathological conditions, which gives rise to the development of CVDs. Therefore, EVs hold tremendous potential to prevent, diagnose and treat CVDs. The current article reviews the specific functions of EVs in different CVDs.

Objectives The oldest old population has become the fastest growing segment with excess need of care and social support, it is crucial to improve the health-related quality of life (HRQoL) of these populations. This study seeks to evaluate the health status and to investigate modifiable factors associated with health-related quality of life for oldest old adults in China. Design A cross-sectional population-based study. Setting Hainan Province in the south of China. Participants 1,278 adults aged 80 years or older. Methods HRQoL was assessed by three-level EuroQol-5D scale (EQ-5D-3L) and a visual analogue scale (VAS). Demographic and health-related variables were analysed by estimating mean values and standard deviations for continuous variables, percentages and standard deviations for categorical variables. Tobit regressions, ordinary least Squared (OLS) regressions and ordered probit regressions were adopted to determine the associated factors for overall HRQoL and for each health dimension. Results Anxiety/depression was the least reported problem while mobility was the most frequently reported with problem. Female respondents had lower EQ-5D score (0.76 vs. 0.86) and VAS score (66.55 vs. 69.84) than male respondents. Better health-related quality of life was significantly associated with higher BMI, no drinking habit, more leisure activities, living with family members, good sleeping quality, closer social and family connections, fewer numbers of drugs consumed per day, without having hearing or visual impairment, and fewer chronic conditions, after controlling for potential confounders. Conclusion Findings from this study suggested that quality of life was not only associated with age-related diseases, but also correlated with a range of health-related lifestyles, and factors indicating social and family support.

The proportion of the world population aged 60 years or over is expected to increase from 12% in 2013 to 21% in 2050. This increase will represent more than 2 billion elderly individuals, including 400 million people aged 80 years or older and 3.4 million centenarians in 2050.¹ The population of individuals of advanced ages, including near-centenarians and centenarians, has become the fastest-growing segment of the population.² This growth has led to considerable concern about the social and economic burden of disease and disability in this age group, for the oldest old are vulnerable to multiple age-related chronic conditions and disabilities and are at a high risk of...