Prevalence and Risk Factors for Frailty among Community-Dwelling Older People in China: A Systematic Review and Meta-Analysis

OBJECTIVE

To systematically assess the prevalence of frailty, including prefrailty, stratified prevalence according to frailty criteria, gender, age, and region, and the risk factors for frailty in China.

DESIGN

We conducted a systematic literature review and meta-analysis using articles available in 8 databases including PubMed, Cochrane Library, Web of Science, CINAHL Plus, China Knowledge Resource Integrated Database (CNKI), Wanfang Database, Chinese Biomedical Database (CBM), and Weipu Database (VIP).

SETTING

Cross-sectional and cohort data from Chinese community.

PARTICIPANTS

Community-dwelling adults aged 65 and older.

MEASUREMENTS

Two authors independently extracted data based upon predefined criteria. Where data were available we conducted a meta-analysis of frailty parameters using a random-effects model.

RESULTS

We screened 915 different articles, and 14 studies (81258 participants) were ultimately included in this analysis. The prevalence of frailty and prefrailty in individual studies varied from 5.9% to 17.4% and from 26.8% to 62.8%, respectively. The pooled prevalence of frailty and prefrailty were 10% (95% CI: 8% to 12%, I2 = 97.4%, P = 0.000) and 43% (95% CI: 37% to 50%, I2 = 98.0%, P = 0.000), respectively. The pooled frailty prevalence was 8% for the Fried frailty phenotype, 12% for the frail index, and 15% for the FRAIL scale. Age-stratified meta-analyses showed the pooled prevalence of frailty to be 6%, 15%, and 25% for those aged 65-74, 75-84, and ≥85 years old, respectively. The pooled prevalence of frailty was 8% for males and 11% for females. The pooled prevalence of frailty in Mainland China, Taiwan, and Hong Kong was 12%, 8%, and 14%, respectively. The pooled frailty prevalence was 10% in urban areas and 7% in rural areas. After controlling for confounding variables, increasing age (OR = 1.28, 95% CI: 1.2 to 1.36, I2 = 98.0%, P = 0.000), being female (OR = 1.29, 95% CI: 1.16 to 1.43, I2 =92.7%, P=0.000), activities of daily living (ADL) disability (OR = 1.72, 95% CI: 1.57 to 1.90, I2 = 99.7%, P = 0.000), and having three or more chronic diseases (OR = 1.97, 95% CI: 1.78 to 2.18, I2 = 97.5%, P = 0.000) were associated with frailty.

CONCLUSIONS

These findings of this review indicate an overall pooled prevalence of frailty among Chinese community-dwelling older people of 10%. Increasing age, being female, ADL disability, and having three or more chronic diseases were all risk factors for frailty. Further research will be needed to identify additional frailty risk factors in order to better treat and prevent frailty in the community.

Disrupted Coupling Between the Spontaneous Fluctuation and Functional Connectivity in Idiopathic Generalized Epilepsy

Purpose: The purpose of this study was to comprehensively evaluate alterations of resting-state spontaneous brain activity in patients with idiopathic generalized epilepsy (IGE) and its subgroups [juvenile myoclonic epilepsy (JME) and generalized tonic-clonic seizures (GTCS)]. Methods: Resting state functional magnetic resonance imaging (fMRI) data were acquired from 60 patients with IGE and 60 healthy controls (HCs). Amplitude of low frequency fluctuation (ALFF), global functional connectivity density (gFCD), local FCD (lFCD), and long range FCD (lrFCD) were used to evaluate spontaneous brain activity in the whole brain. Moreover, the coupling between ALFF and FCDs (gFCD, lFCD, and lrFCD) was analyzed on both voxel-wise and subject-wise levels. Two-sample t-tests were used to analyze the difference in ALFF, FCDs and coupling on a subject-wise level between the two groups. Nonparametric permutation tests were used to evaluate differences in coupling on a voxel-wise level. Key findings: Patients with IGE and its subgroups showed reduced ALFF, gFCD and lrFCD in posterior regions of the default mode network (DMN). In addition, decreased ALFF and increased coupling with FCD were found in the cerebellum, while decreased coupling was observed in the bilateral pre- and postcentral gyrus in IGE compared with the coupling in HCs. Similar findings were found in the analysis between each of the two subgroups of IGE (JME and GTCS) and HCs, and JME patients had increased coupling in the cerebellum and bilateral middle occipital gyrus compared with coupling in the GTCS patients. Significance: This study demonstrated a multifactor abnormality of the DMN in IGE and emphasized that the abnormality in the cerebellum was associated with dysfunctional motor symptoms during seizures and might participate in the regulation of GSWDs in IGE.

Evaluation of androgen assay results using a curated Hershberger database

A set of 39 reference chemicals with reproducible androgen pathway effects in vivo, identified in the companion manuscript [1], were used to interrogate the performance of the ToxCast/Tox 21 androgen receptor (AR) model based on 11 high throughput assays. Cytotoxicity data and specificity confirmation assays were used to distinguish assay loss-of-function from true antagonistic signaling suppression. Overall agreement was 66% (19/29), with ten additional inconclusive chemicals. Most discrepancies were explained using in vitro to in vivo extrapolation to estimate equivalent administered doses. The AR model had 100% positive predictive value for the in vivo response, i.e. there were no false positives, and chemicals with conclusive AR model results (agonist or antagonist) were consistently positive in vivo. Considering the lack of reproducibility of the in vivo Hershberger assay, the in vitro AR model may better predict specific AR interaction and can rapidly and cost-effectively screen thousands of chemicals without using animals.

[Analysis of blood flow energy characteristics of pulsatile and non-pulsatile flow during extracorporeal circulation]

Objective: To analyze the magnitude of blood flow energy and characteristics of frequency domain between pulsatile flow and nonpulsatile flow during cardiopulmonary bypass and physiological flow. Methods: From January 2017 to December 2017, 60 cases of patients with mitral valve disease scheduled for mitral valve replacement or repair at Department of Cardiasurgery, Shanghai Chest Hospital, Shanghai Jiaotong University were randomly divided into 2 groups: pulsatile perfusion (PP) and non-pulsatile perfusion (NP). The magnitude of blood flow energy during pulsatile and non-pulsatile was calculated using energy equivalent pressure (EEP) and surplus hemodynamic energy (SHE) while fast Fourier transformation (FFT) was used to perform power spectral density analysis to identify the frequency domain characteristics between artificial and physiological flow (prior to CPB). The data was analyzed by analysis of variance or t test. Results: At the different time-points after occlusion, the EEP and SHE in PP group were respectively 1.52 to 1.62 and 2.03 to 2.22 times higher than NP at the distal of artery filter. The power density analysis revealed that the blood flow energy of physiological pulsatile flow patterns was within 40 Hz and the ratio of low frequency energy was more than 90% before clamp. The spectral energy ratio of low frequency decreased in both group compared with physiological flow was more obvious in NP group at the radial artery. The ratio of estimated value of power density of PP and NP groups analysis showed the corresponding 0 to 5 Hz, 0 to 10 Hz, 0 to 40 Hz frequency range values measured at the radial artery and filter were 9.51, 4.68, 3.59 and 3.87, 2.69, 2.38 respectively after occulusion. In each frequency range, the energy of PP is higher than that of NP, and the lower the frequency, the greater the difference. The ratio of estimated value of power density of PP and NP groups for the three frequencies measured at the radial artery before and after occlusion were 2.86, 2.83, 2.75 and 14.70, 12.74, 9.85 respectively, and decreased significantly in NP group and low frequency energy. The ratio of estimated value of power density of PP and NP groups under the three different frequencies measured at the radial artery and filter were 26.35, 33.15, 37.36 and 37.41, 54.18, 56.64 respectively, in the conduction process from filter to radial artery, energy exhaustion is significant, especially in group NP. Conclusions: The PP provides significantly more energy than the NP whereby the PP is closer to the physiological pulsatile on the energy frequency structure and attenuation characteristics, with mainly low frequency energy of 0 to 5 Hz and weak energy attenuation. The energy loss of non-pulsatile flow is obvious, especially the low frequency energy.

Abnormal brain activation during threatening face processing in schizophrenia: A meta-analysis of functional neuroimaging studies

Impairment of face perception in schizophrenia is a core aspect of social cognitive dysfunction. This impairment is particularly marked in threatening face processing. Identifying reliable neural correlates of the impairment of threatening face processing is crucial for targeting more effective treatments. However, neuroimaging studies have not yet obtained robust conclusions. Through comprehensive literature search, twenty-one whole brain datasets were included in this meta-analysis. Using seed-based d-Mapping, in this voxel-based meta-analysis, we aimed to: 1) establish the most consistent brain dysfunctions related to threating face processing in schizophrenia; 2) address task-type heterogeneity in this impairment; 3) explore the effect of potential demographic or clinical moderator variables on this impairment. Main meta-analysis indicated that patients with chronic schizophrenia demonstrated attenuated activations in limbic emotional system along with compensatory over-activation in medial prefrontal cortex (MPFC) during threatening faces processing. Sub-task analyses revealed under-activations in right amygdala and left fusiform gyrus in both implicit and explicit tasks. The remaining clusters were found to be differently involved in different types of tasks. Moreover, meta-regression analyses showed brain abnormalities in schizophrenia were partly modulated by age, gender, medication and severity of symptoms. Our results highlighted breakdowns in limbic-MPFC circuit in schizophrenia, suggesting general inability to coordinate and contextualize salient threat stimuli. These findings provide potential targets for neurotherapeutic and pharmacological interventions for schizophrenia.

Genetic and clinical findings in a Chinese cohort of patients with collagen VI-related myopathies

Collagen VI-related myopathy, caused by pathogenic variants in the genes encoding collagen VI, represents a clinical continuum from Ullrich congenital muscular dystrophy (UCMD) to Bethlem myopathy (BM). Clinical data of 60 probands and their family members were collected and muscle biopsies of 26 patients were analyzed. COL6A1, COL6A2 and COL6A3 exons were analyzed by direct sequencing or next generation sequencing (NGS). Sixty patients were characterized by delayed motor milestones, muscle weakness, skin and joint changes with 40 UCMD and 20 BM. Muscle with biopsies revealed dystrophic changes and showed completely deficiency of collagen VI or sarcolemma specific collagen VI deficiency. We identified 62 different pathogenic variants in these 60 patients, with 34 were first reported while 28 were previously known; 72 allelic pathogenic variants in COL6A1 (25/72, 34.7%), COL6A2 (33/72, 45.8%) and COL6A3 (14/72, 19.4%). We also found somatic mosaic variant in the parent of 1 proband by personal genome machine amplicon deep sequencing for mosaicism. Here we provide clinical, histological and genetic evidence of collagen VI-related myopathy in 60 Chinese patients. NGS is a valuable approach for diagnosis and accurate diagnosis provides useful information for genetic counseling of related families.

Dysfunction of Large-Scale Brain Networks in Schizophrenia: A Meta-analysis of Resting-State Functional Connectivity

Schizophrenia is a complex mental disorder with disorganized communication among large-scale brain networks, as demonstrated by impaired resting-state functional connectivity (rsFC). Individual rsFC studies, however, vary greatly in their methods and findings. We searched for consistent patterns of network dysfunction in schizophrenia by using a coordinate-based meta-analysis. Fifty-six seed-based voxel-wise rsFC datasets from 52 publications (2115 patients and 2297 healthy controls) were included in this meta-analysis. Then, coordinates of seed regions of interest (ROI) and between-group effects were extracted and coded. Seed ROIs were categorized into seed networks by their location within an a priori template. Multilevel kernel density analysis was used to identify brain networks in which schizophrenia was linked to hyper-connectivity or hypo-connectivity with each a priori network. Our results showed that schizophrenia was characterized by hypo-connectivity within the default network (DN, self-related thought), affective network (AN, emotion processing), ventral attention network (VAN, processing of salience), thalamus network (TN, gating information) and somatosensory network (SS, involved in sensory and auditory perception). Additionally, hypo-connectivity between the VAN and TN, VAN and DN, VAN and frontoparietal network (FN, external goal-directed regulation), FN and TN, and FN and DN were found in schizophrenia. Finally, the only instance of hyper-connectivity in schizophrenia was observed between the AN and VAN. Our meta-analysis motivates an empirical foundation for a disconnected large-scale brain networks model of schizophrenia in which the salience processing network (VAN) plays the core role, and its imbalanced communication with other functional networks may underlie the core difficulty of patients to differentiate self-representation (inner world) and environmental salience processing (outside world).

The Risks of Overweight, Obesity and Abdominal Obesity in Middle Age after Exposure to Famine in Early Life: Evidence from the China's 1959-1961 Famine

OBJECTIVE

Several studies have revealed that exposure to famine in early life was associated with higher body mass index(BMI) and waist circumference, and most of them used data from cross-sectional studies and defined those born before or after the famine period as non-exposed participants, which ignored the effects caused by age. Our objective was to study the effects of undernutrition in early life on overweight, obesity and abdominal obesity in those aged 54-56.

METHODS

This was a retrospective cohort study with the status at age of 54-56 as outcomes. 1092 participants born between 1959 and 1961 from 2015 wave of China Health and Retirement Longitudinal Study (CHARLS) were defined as exposed and 1616 born between 1955 and 1957 from 2011 wave of CHARLS were defined as control. We used the prevalence odds ratios(ORs) to estimate the risks of overweight, obesity, abdominal obesity, and stratified by famine severity and sex separately for comparisons.

RESULTS

Exposed group had higher risks of overweight (OR 1.357, 95%CI 1.067,1.727) and obesity (OR 1.356, 95%CI 1.001,1.836) in women, not in men. Participants in exposed group were more likely to have abdominal obesity (OR 1.362, 95%CI 1.139,1.629), regardless of famine severity and gender.

CONCLUSION

Undernutrition in early life increased the risks of overweight and obesity in women not in men. And the risk of abdominal obesity was increased with the experience of undernutrition at early age both in men and women.

TXNDC5 contributes to rheumatoid arthritis by down-regulating IGFBP1 expression

The thioredoxin domain-containing 5 (TXNDC5) gene is associated with susceptibility to rheumatoid arthritis (RA) and exhibits increased expression in the synovial tissues. TXNDC5 is also associated strongly with diabetes, a metabolic disease characterized by interrupted insulin signalling. This study investigated whether TXNDC5 contributes to RA via the insulin signalling pathway. In this study, RA synovial fibroblast-like cells (RASFs) transfected with an anti-TXNDC5 small interfering RNA (siRNA) were analysed with an insulin signaling pathway RT² profiler polymerase chain reaction (PCR) array and an insulin resistance RT² profiler PCR array. The PCR arrays detected significantly increased expression of insulin-like growth factor binding protein 1 (IGFBP1) in RASFs with suppressed TXNDC5 expression. The result was verified using real-time PCR and Western blot analyses. Significantly elevated IGFBP1 expression and decreased interleukin (IL)-6 secretion were also detected in culture medium of transfected RASFs. Furthermore, decreased IGFBP1 mRNA and protein expression levels were detected in RA synovial tissues. Additionally, significantly increased apoptosis and decreased cell proliferation and cell migration were observed in RASFs transfected with the anti-TXNDC5 siRNA, whereas transfection with the anti-IGFBP1 siRNA or a mixture of the anti-IGFBP1 and anti-TXNDC5 siRNAs restored normal cell proliferation, migration and IL-6 level in RASFs. Insulin-like growth factor (IGF) has potent prosurvival and anti-apoptotic functions, and IGFBP1 can suppress IGF activity. Based on the results of the present study, we suggest that TXNDC5 contributes to abnormal RASF proliferation, migration and IL-6 production by inhibiting IGFBP1 expression.

White Matter Connectivity Pattern Associate with Characteristics of Scalp EEG Signals

The rhythm of electroencephalogram (EEG) depends on the neuroanatomical-based parameters such as white matter (WM) connectivity. However, the impacts of these parameters on the specific characteristics of EEG have not been clearly understood. Previous studies demonstrated that, these parameters contribute the inter-subject differences of EEG during performance of specific task such as motor imagery (MI). Though researchers have worked on this phenomenon, the idea is yet to be understood in terms of the mechanism that underlies such differences. Here, to tackle this issue, we began our investigations by first examining the structural features related to scalp EEG characteristics, which are event-related desynchronizations (ERDs), during MI using diffusion MRI. Twenty-four right-handed subjects were recruited to accomplish MI tasks and MRI scans. Based on the high spatial resolution of the structural and diffusion images, the motor-related WM links, such as basal ganglia (BG)-primary somatosensory cortex (SM1) pathway and supplementary motor area (SMA)-SM1 connection, were reconstructed by using probabilistic white matter tractography. Subsequently, the relationships of WM characteristics with EEG signals were investigated. These analyses demonstrated that WM pathway characteristics, including the connectivity strength and the positional characteristics of WM connectivity on SM1 (defined by the gyrus-sulcus ratio of connectivity, GSR), have a significant impact on ERDs when doing MI. Interestingly, the high GSR of WM connections between SM1 and BG were linked to the better ERDs. These results therefore, indicated that the connectivity in the gyrus of SM1 interacted with MI network which played the critical role for the scalp EEG signal extraction of MI to a great extent. The study provided the coupling mechanism between structural and dynamic physiological features of human brain, which would also contribute to understanding individual differences of EEG in MI-brain computer interface.

RNA-seq analysis of amygdala tissue reveals characteristic expression profiles in schizophrenia

The amygdala brain region has been implicated in the pathophysiology of schizophrenia through emotion processing. However, transcriptome messages in the amygdala of schizophrenia patients have not been well studied. We used RNA sequencing to investigate gene-expression profiling in the amygdala tissues, and identified 569 upregulated and 192 downregulated genes from 22 schizophrenia patients and 24 non-psychiatric controls. Gene functional enrichment analysis demonstrated that the downregulated genes were enriched in pathways such as 'synaptic transmission' and 'behavior', whereas the upregulated genes were significantly over-represented in gene ontology pathways such as 'immune response' and 'blood vessel development'. Co-expression-based gene network analysis identified seven modules including four modules significantly associated with 'synaptic transmission', 'blood vessel development' or 'immune responses'. Taken together, our study provides novel insights into the molecular mechanism of schizophrenia, suggesting that precision-tailored therapeutic approaches aimed at normalizing the expression/function of specific gene networks could be a promising option in schizophrenia.

Shared abnormality of white matter integrity in schizophrenia and bipolar disorder: A comparative voxel-based meta-analysis

Patients with schizophrenia and bipolar disorder (BD) shared a significant overlap in genetic susceptibility, pharmacological treatment responses, neuropsychological deficits, and epidemiological features. However, it remains unknown whether these clinical overlaps are mediated by shared or disorder-specific abnormalities of white matter integrity. In this voxel-based meta-analytic comparison of whole-brain white matter integrity, we aimed to identify the shared or disorder-specific structural abnormalities between schizophrenia and BD. A comprehensive literature search was conducted up to February 2016 to identify studies that compared between patients and healthy controls (HC) by using whole-brain diffusion approach (schizophrenia: 24 datasets with 754 patients vs. 775 HC; BD: 23 datasets with 705 patients vs. 679 HC). Voxel-wise meta-analyses were conducted and restricted to unified template using seed-based d-Mapping. Abnormal white matter integrity was calculated within each condition and a direct comparison of effect size was performed of alterations between two conditions. Two regions with significant reductions of fractional anisotropy (FA) characterized abnormal water diffusion in both disorders: the genu of the corpus callosum (CC) and posterior cingulum fibers. There was no significant difference found between the two disorders. Our results highlighted shared impairments of FA at genu of the CC and left posterior cingulum fibers, which suggests that, phenotypic overlap between schizophrenia and BD could be related to common brain circuit dysfunction.