[Associations of body mass index and waist circumference with risk of chronic kidney disease in adults in China].

Objective: To examine the associations of BMI and waist circumference (WC) with the risk of chronic kidney disease (CKD) and its subtypes in adults in China. Methods: The data from the China Kadoorie Biobank were used. After excluding those with cancer, coronary heart disease, stroke, or CKD at baseline survey, 480 430 participants were included in this study. Their body height and weight, and WC were measured at baseline survey. Total CKD was defined as diabetic kidney disease (DKD), hypertensive nephropathy (HTN), glomerulonephritis (GN), chronic tubulointerstitial nephritis (CTIN), obstructive nephropathy (ON), CKD due to other causes, and chronic kidney failure. Cox proportional hazards regression model was used to estimate the associations between exposure factors and risks of outcomes. Results: During a follow-up period of (11.8±2.2) years, 5 486 cases of total CKD were identified, including 1 147 cases of DKD, 340 cases of HTN, 1 458 cases of GN, 460 cases of CTIN, 598 cases of ON, 418 cases of CKD due to other causes, and 1 065 cases of chronic kidney failure. After adjusting for socio-demographic factors, lifestyle factors, baseline prevalence of hypertension and diabetes, and WC and compared to participants with normal BMI (18.5-23.9 kg/m2), the hazard ratios (HRs) of total CKD for underweight (<18.5 kg/m2), overweight (24.0-27.9 kg/m2), and obese (≥28.0 kg/m2) were 1.42 (95%CI: 1.23-1.63), 1.00 (95%CI: 0.93-1.08) and 0.98 (95%CI: 0.87-1.10), respectively. Stratification analysis by WC showed that BMI was negatively associated with risk for total CKD in non-central obese participants (WC: <85.0 cm in men and <80.0 cm in women) (HR=0.97, 95%CI: 0.96-0.99), while the association was positive in central obese participants (≥90.0 cm in men and ≥85.0 cm in women) (HR=1.03, 95%CI: 1.01-1.05). The association between BMI and GN was similar to that of total CKD. BMI was associated with an increased risk for HTN, with a HR of 1.12 (95%CI: 1.06-1.18) per 1.0 kg/m2 higher BMI. After adjusting for potential confounders and BMI, compared to participants with non-central obesity, the HRs for pre-central obesity (WC: 85.0-89.9 cm in men and 80.0-84.9 in women) and central obesity were 1.26 (95%CI: 1.16-1.36) and 1.32 (95%CI: 1.20-1.45), respectively. With the exception of HTN and CTIN, WC was positively associated with risks for all CKD subtypes. Conclusions: BMI-defined underweight and central obesity were independent risk factors for total CKD, and BMI and WC had different associations with risks for disease subtypes.

[An observational and Mendelian randomization study of the associations of body mass index with plasma amino acids and acylcarnitines in Chinese adults].

Objective: To explore the relationship between BMI and levels of plasma amino acids and acylcarnitines in Chinese adults. Methods: Based on 2 182 individuals with targeted mass spectrometry metabolomic measurements from the first resurvey of the China Kadoorie Biobank, we assessed the linear and nonlinear associations between BMI and plasma levels of 20 amino acids and 40 acylcarnitines using linear regression models and restricted cubic spline models, and identified BMI-related metabolic pathways. We conducted one-sample Mendelian randomization (MR) with BMI genetic risk scores as the instrumental variable further to explore the potential causal relationships between BMI and 20 amino acids and 40 acylcarnitines, and tested for horizontal pleiotropy using the MR-Egger method. Results: Observational analyses found that BMI was associated with increased plasma levels of 3 branched-chain amino acids (isoleucine, leucine, and valine), 2 aromatic amino acids (phenylalanine and tyrosine), 3 other amino acids (cysteine, glutamate, lysine), and 7 acylcarnitines (C3, C4, C5, C10, C10:1, C14, and C16), and with decreased circulating levels of asparagine, serine, and glycine. Pathway analysis identified 7 BMI-related amino acids metabolic pathways (false discovery rate corrected all P<0.05), including branched-chain amino acids and aromatic amino acids biosynthesis, glutathione metabolism, etc. BMI showed a nonlinear relationship with leucine, valine, and threonine, and a linear relationship with other amino acids and acylcarnitines. One-sample MR analyses revealed that BMI was associated with elevated levels of tyrosine and 4 acylcarnitines [C5-DC(C6-OH), C5-M-DC, C12-DC, and C14], with tyrosine and acylcarnitine C14 positively correlated with BMI in both observational [the ß values (95%CIs) were 0.057 (0.044-0.070) and 0.018 (0.005-0.032), respectively] and One-sample MR analyses [the ß values (95%CIs) were 0.102 (0.035-0.169) and 0.104 (0.036-0.173), respectively]. The MR analyses of the current study satisfied the 3 core assumptions of instrumental variable. Conclusions: BMI was associated with circulating 11 amino acids and 7 acylcarnitines in Chinese adults, involving several pathways such as branched-chain amino acid and aromatic amino acid metabolism, fatty acid metabolism, and oxidative stress. There may be a causal relationship between BMI and tyrosine and acylcarnitine C14.

[Distribution and influencing factors of lipoprotein (a) levels in non-arteriosclerotic cardiovascular disease population in China].

Objective: To describe the distribution of lipoprotein (a) [Lp(a)] levels in non-arteriosclerotic cardiovascular disease (ASCVD) population in China and explore its influencing factors. Methods: This study was based on a nested case-control study in the CKB study measured plasma biomarkers. Lp(a) levels was measured using a polyclonal antibody-based turbidimetric assay certified by the reference laboratory and ≥75.0 nmol/L defined as high Lp(a). Multiple logistic regression model was used to examine the factors related to Lp(a) levels. Results: Among the 5 870 non-ASCVD population included in the analysis, Lp(a) levels showed a right-skewed distribution, with a M (Q1, Q3) of 17.5 (8.8, 43.5) nmol/L. The multiple logistic regression analysis found that female was associated with high Lp(a) (OR=1.23, 95%CI: 1.05-1.43). The risk of increased Lp(a) levels in subjects with abdominal obesity was significantly reduced (OR=0.68, 95%CI: 0.52-0.89). As TC, LDL-C, apolipoprotein A1(Apo A1), and apolipoprotein B(Apo B) levels increased, the risk of high Lp(a) increased, with OR (95%CI) for each elevated group was 2.40 (1.76-3.24), 2.68 (1.36-4.93), 1.29 (1.03-1.61), and 1.65 (1.27-2.13), respectively. The risk of high Lp(a) was reduced in the HDL-C lowering group with an OR (95%CI) of 0.76 (0.61-0.94). In contrast, an increase in TG levels and the ratio of Apo A1/Apo B(Apo A1/B) was negatively correlated with the risk of high Lp(a), with OR (95%CI) of 0.73 (0.60-0.89) for elevated triglyceride group, and OR (95%CI) of 0.60 (0.50-0.72) for the Apo A1/B ratio increase group (linear trend test P≤0.001 except for Apo A1). However, no correlation was found between Lp(a) levels and lifestyle factors such as diet, smoking, and physical activity. Conclusions: Lp(a) levels were associated with sex and abdominal obesity, but less with lifestyle behaviors.

[Progress in research of relationship between marital status and cancer].

In recent 30 years, the global burden of cancer has become more serious, and one of social problem is population aging, plus declining birth rate, declining marriage rate and increasing divorce rate. Marriage is one of the most intimate and long-term social relations, and previous research had piecemeal reports of its impact on cancer morbidity and mortality without systematic review of evidence in high-quality population based epidemiological research. This paper summarizes the progress in research of the relationship between marital status and cancer to provide reference for future research and cancer prevention and control.

[Current status of tuberculosis burden in China].

Tuberculosis, caused by Mycobacterium tuberculosis, is an infectious disease that most often affects the lungs. China is still among the high-burden tuberculosis countries in the world. Although the estimated incidence of tuberculosis in China has declined in recent years, the declining rate is slow. It still faces major issues such as a slower rate of decline, a widening gap between estimated and notified incidence, higher risk among middle-aged and older adults, a high number of cases among agriculture and related workers, and a heavier disease burden in the country's western regions. In addition, latent tuberculosis infection, drug-resistant tuberculosis, tuberculosis coinfection with HIV, and extrapulmonary tuberculosis have also exacerbated the disease burden of tuberculosis to some extent. This paper reviewed the epidemic characteristics of tuberculosis, the epidemiological triad, three links and two factors in the transmission process, the disease burden, and other aspects to provide a reference for formulating prevention and control strategies on tuberculosis.

[Overview of the ten global conferences on health promotion and implications for future work].

Since 1986, the WHO has held ten global health promotion conferences covering various health promotion issues and sustainable development worldwide. These sessions have formed a series of consensus and actions that guide promoting health globally. This study analyzed the declarations, reports, and news materials from the ten conferences that studied health promotion action areas, focal topics, actor networks, partnership relationships, and other significant outcomes. It also explored how these conferences contributed to the construction and advancement of global health promotion consensus and actions. The first Global Conference on Health Promotion identified the concept of health promotion and five key action areas, laying the foundation for subsequent conferences and health promotion actions. Over the years, the ten conferences continuously expanded the essence of health promotion, developed partnership relationships, formulated public health promotion policies, and called for health promotion actions. This process culminated in the formation of global consensus and collective actions. The latter conferences have gained significant attention and influence. The conferences offer valuable insights for future global health promotion endeavors and provide global perspectives and pathways for the development of Healthy China.

[Physical activity and its influencing factors in patients with diabetes mellitus: a comparative study between China and the United Kingdom].

Objective: To compare the differences in low-level physical activity (PA) and related influencing factors in patients with diabetes mellitus in China and the United Kingdom (UK). Methods: Using baseline survey data from the China Kadoorie Biobank and the UK Biobank, we analyzed the association between diabetes mellitus and low-level PA using logistic regression, with the participants' self-reported whether they had diabetes mellitus as the independent variable, and low-level PA as the dependent variable. Results: We included 509 254 Chinese adults and 359 763 British adults in the analysis. After adjusting for multiple factors, we found that both Chinese and British patients with diabetes mellitus were at elevated risk for low-level PA, with corresponding ORs (95%CIs) of 1.15 (1.12-1.19) and 1.37 (1.32-1.41), respectively. Patients with diabetes mellitus with longer disease duration and poorer glycemic control were at greater risk of having low-level of PA. Female, rural-distributed, employed, never-smoking Chinese diabetics, and male, urban-distributed, retired/unemployed, quit-smoking British diabetics were more likely to have low-level PA. Conclusions: Chinese and British patients with diabetes mellitus were more likely to have low-level PA compared with the general population, but the risk of low-level PA for patients in both countries varied by population characteristics. Therefore, PA guidelines and intervention measures should be based on the characteristics of individuals in the target countries and regions, which could improve PA levels among patients with diabetes mellitus.

[Current major public health challenges].

After COVID-19 pandemic, there are still many public health challenges in the world. The double burden of communicable and non-communicable diseases is still heavy in many countries. Mental health and injury are crucial public health problems which are often neglected. Environmental health and food and drug safety are closely related to human health, to which further management and intervention are needed. These problems have different impacts on people at different life stages, resulting in health problems throughout the life course. The current status of public health is far from the requirements set by the Sustainable Development Goals of United Nations or the initiative of "Healthy China 2030". It is necessary for governments and related departments of all countries to consider public health in all policy development to tackle the major challenge to public health.

[Prevalence of urinary incontinence in middle-aged and elderly adults in 10 areas in China].

Objective: To describe the population and area distribution differences in the prevalence of urinary incontinence in middle-aged and elderly adults in 10 areas in China. Methods: A total of 24 913 participants aged 45-95 years who completed the third resurvey of China Kadoorie Biobank during 2020-2021 were included. The prevalence of urinary incontinence was assessed by an interviewer-administered questionnaire, and urinary incontinence was classified as only stress urinary incontinence, only urgency urinary incontinence and mixed urinary incontinence. The prevalence of urinary incontinence and its subtypes were reported by sex, age and area, and the severity of urinary incontinence and treatment were described. Results: The average age of the participants was (65.4±9.1) years. According to the seventh national census data in 2020, the age-standardized prevalence rates of urinary incontinence was 25.4% in women and 7.0% in men. The age-standardized prevalence rates of only stress, only urgency and mixed incontinence were 1.7%, 4.2% and 1.2% in men and 13.5%, 5.8% and 6.1% in women, respectively. The prevalence rates of urinary incontinence and all subtypes in men and the prevalence of urinary incontinence and all subtypes except only stress urinary incontinence in women all increased with age (P<0.001). After adjusting for age, the prevalence of urinary incontinence in both men and women were higher in rural area than in urban area (P<0.001). The treatment rates in men and women with urinary incontinence were 15.4% and 8.5%, respectively. Conclusions: The prevalence of urinary incontinence was high in middle-aged and elderly adults in China, and the prevalence rate was higher in women than in men, but the treatment rate of urinary incontinence was low.

[Progress and practice of objective measurement of physical behaviors in large-scale cohort research].

Due to the limited reliability of traditional self-completed questionnaire, the accuracy of measurement of physical behaviors (physical activity, sedentary behavior and sleep) is not high. With the development of technology, wearable devices (e.g. accelerometer) can be used for more accurate measurement of physical behaviors and have great application potential in large-scale research. However, the data of objective measurement of physical behaviors from large-scale cohort research in Asian populations is still limited. Between August 2020 and December 2021, the 3rd resurvey of China Kadoorie Biobank (CKB) project used Axivity AX3 wrist triaxial accelerometer to collect the data of participants' daily activity and sleep status. A total of 20 370 participants from 10 study areas were included in the study, in whom 65.2% were women, and the age was (65.4±9.1) years. The participants' physical activity level varied greatly in different study areas. The objective measurement of participants' physical behaviors in CKB project has provided valuable resources for the description of 24-hour patterns of physical behaviors and evaluation of the health effect of physical activity, sedentary behavior and sleep as well as their association with diseases in the elderly in China.

[Epidemiological characteristics of preserved vegetable intake in adults in 10 areas of China].

Objective: To describe the epidemiological characteristics of intakes of different types of preserved vegetables in participants from the China Kadoorie Biobank (CKB). Methods: The CKB project conducted baseline survey, the first resurvey, and the second resurvey during 2004-2008, 2008, and 2013-2014, respectively. According to the average intake levels of salted and sour pickled vegetables in the second resurvey, the 10 survey areas were classified as the area where people mainly consumed salted vegetables, the area where people mainly consumed sour pickled vegetables, and the area where people rarely consumed preserved vegetables. For the first two areas, logistic regression model was used to describe the temporal trends and population distribution of preserved vegetable intake and analyze the distribution of other dietary factors. Results: The area where people mainly consumed salted vegetables included Qingdao, Harbin, Suzhou, and Zhejiang (baseline participant number: 204 036), while the area where people mainly consumed sour pickled vegetables included Gansu and Sichuan (baseline participant number: 105 573). In the area where people mainly consumed salted vegetables, the average intake frequencies of preserved vegetables was 3.1, 3.3, and 1.8 days/week in the baseline survey, the first resurvey, and the second resurvey, respectively, showing a declining trend (P<0.001). Similarly, the average intake frequencies of preserved vegetables were 2.8, 2.7, and 1.6 days/week in the baseline survey, the first resurvey and the second resurvey in the area where people mainly consumed sour pickled vegetables (P<0.001). At baseline survey, the married and those had lower education level tended to have more preserved vegetable intakes in both areas (P<0.001). In the area where people mainly consumed salted vegetables, the elderly had higher frequency of preserved vegetable intake (P<0.001), which was converse in the area where people mainly consumed sour pickled vegetables. In the participants with higher frequency of preserved vegetable intake, more people consumed spicy food daily and preferred salty food (P<0.05). Conclusions: The area and population specific differences in the type and frequency of preserved vegetable intake were observed in adults in the CKB project in China. Besides, the average level of preserved vegetable intake showed a declining trend. Preserved vegetable intake might be associated with other dietary habits.

[A prospective cohort study of factors associated with longevity in older adults in 10 areas of China].

Objective: To evaluate the associations of sociodemographic characteristics and lifestyle factors with longevity status in older adults in China. Methods: After excluding those born after 31st December 1938, a total of 51 870 older adults from the China Kadoorie Biobank (CKB) were included. The attained age was defined according to the survival age or age on 31st December 2018. According to the attained age, the old persons were categorized into non-longevity (died before age 80 years) and longevity (attained age ≥80 years). The longevity group was further divided into two groups: longevity with death occurring before 2019, and longevity and survival to 2019. The information about socio-demographic characteristics and lifestyles was collected at the 2004-2008 baseline survey. Multinomial logistic regression models were used to analyze the associations between exposure factors and outcomes by taking the non-longevity group as the reference group. Results: A total of 51 870 older adults aged 65-79 years in the baseline survey were included for analysis. During a follow-up for (10.2±3.5) years, 38 841 participants were longevity, and 30 354 participants still survived at the end of 2018. Compared to men, rural populations, non-married individuals, those with an annual household income of less than 10 000 yuan, and those with education levels of primary school or below, the adjusted ORs(95%CI) for longevity and survival to 2019 in women, urban residents, married individuals, those with annual household incomes ≥20 000 yuan, and those with education levels of college or university were 1.68 (1.58-1.78), 1.69 (1.61-1.78), 1.15 (1.10-1.21), 1.44 (1.36-1.53), and 1.32 (1.19-1.48), respectively. The OR (95%CI) for longevity and survival to 2019 was 1.09 (1.08-1.10) for those with an increase of 4 MET-hour/day in total physical activity level. With those who never or almost never smoked, had no alcohol drinking every week, had normal weight (BMI: 18.5-23.9 kg/m2), and WC <85 cm (man)/<80 cm (woman) as the reference groups, the ORs(95%CI) of longevity and survival to 2019 were 0.64 (0.60-0.69) for those smoking ≥20 cigarettes per day, 1.29 (1.14-1.46) for those with alcohol drinking every week, 1.13 (1.01-1.26) for those with pure alcohol drinking <30 g per day, 0.56 (0.52-0.61) for those being underweight, 1.27 (1.19-1.36) for those being overweight, 1.23 (1.11-1.36) for those with obesity, and 0.86 (0.79-0.93) for those with central obesity. Further stratified analysis by WC was performed. In the older adults with WC <85 cm (man)/<80 cm (woman), the ORs (95%CI) of longevity and survival was 1.80 (1.69-1.92) for those with each 5 kg/m2 increase in BMI and 1.02 (0.96-1.08) for those with WC ≥85 cm (man)/≥80 cm (woman). There was a statistically significant difference in the association between BMI and longevity between the two WC groups (interaction test P<0.001). Conclusion: This study showed that women, the married, those with higher socioeconomic status and education level, and those with healthy lifestyles were more likely to achieve longevity.

[Epidemiological distribution of mosaic loss of chromosome Y in adult men in 10 areas in China and its prospective association with lung cancer].

Objective: To detect the prevalence of mosaic loss of chromosome Y in adult men in ten study areas in China, describe the epidemiological distribution of mosaic loss of chromosome Y (mLOY) carriers and assess its prospective association with lung cancer. Methods: Based on the data from baseline survey, genetic analysis and follow-up (as of December 31, 2018) from China Kadoorie Biobank, we used Mosaic Chromosomal Alterations pipeline to detect mLOY carriers in 10 areas in China and described the epidemiological characteristics of mLOY carriers in adult men, including age, area distribution, lifestyle and disease history. We used multivariate logistic regression model to identify the potential relevant factor of mLOY. Cox proportional hazard regression model was fitted to assess the prospective association of mLOY with lung cancer. Stratification analysis were conducted to evaluate the potential modification effects of smoking and age. We also conducted mediation analysis to assess the mediating effect of mLOY in the association between smoking and lung cancer. Results: A total of 42 859 adult men were included in our analysis, in whom 2 458 mLOY carriers were detected (5.7%). The detection rate increased with age (P<0.05). The detection rate was higher in urban area (7.3%±0.2%) than that in rural area (4.7%±0.1%). The results of logistic regression analysis indicated that smoking might be a risk factor for the detection of mLOY (OR=1.49, 95%CI:1.36-1.64). After follow-up for average 11.1 years, 1 041 lung cancer cases were observed. The prospective analysis showed that mLOY carriers had an increased risk for lung cancer by 24% compared with non-mLOY carriers (HR=1.24, 95%CI:1.01-1.52) and expanded mLOY carriers (mLOY cell proportion ≥10%) had an increased risk for lung cancer by 50% (HR=1.50, 95%CI:1.13-2.00). Stratification analysis showed no modification effects of smoking and age in the association between mLOY and lung cancer (interaction P>0.05). Mediation analysis showed that mLOY could be a mediating factor in the association between smoking and lung cancer, the estimated effect was 0.09 (0.01-0.17). Conclusions: There were significant differences in the detection rate of mLOY in adult men with different social-economic characteristics and lifestyles in ten areas in China. Besides, mLOY carriers, especially expanded mLOY carriers, had increased risk for lung cancer and mLOY might be a mediating factor in the association between smoking and lung cancer.

[Comparative study on physical activity and its influencing factors in patients with chronic pulmonary obstructive disease between China and the United Kingdom].

Objective: To compare physical activity and its influencing factors in patients with chronic obstructive pulmonary disease (COPD) between China and the United Kingdom. Methods: We analyzed baseline data from China Kadoorie Biobank and the United Kingdom Biobank among COPD patients who were diagnosed with a one-second rate (FEV1/FVC) less than 70%. Physical activity level was calculated as metabolic equivalent (MET) and divided into three levels: low, medium, and high, according to tertiles stratified by gender and age. Multiple logistic regression was used to estimate ORs and 95%CIs for COPD and Global Initiative for Chronic Obstructive Lung Disease (GOLD) grade about physical activity level, and subgroup analysis was conducted. Results: A total of 506 073 Chinese adults and 231 884 British adults were included. After adjusting for potential confounders, COPD was associated with lower physical activity levels in both Chinese and British COPD patients, with OR (95%CI) of 1.07(1.03-1.10) and 1.03(1.01-1.06) compared with non COPD patients, respectively. The GOLD grade was inversely correlated with physical activity level, particularly in a dose-response manner in the CKB population (trend test P<0.001). The negative relationship was stronger among the elderly, people with less education and lower economic status, and those with a smoking or chronic disease history. Chinese rural COPD patients were at high risk of decline of physical activity. Conclusions: Physical activity is inversely related to COPD, with a dose-response connection to GOLD grade. Therefore, physical activity maintenance and improvement should be encouraged and promoted in COPD patients, especially in high-risk groups.

Modeling functional network topology following stroke through graph theory: functional reorganization and motor recovery prediction

The study of functional reorganization following stroke has been steadily growing supported by advances in neuroimaging techniques, such as functional magnetic resonance imaging (fMRI). Concomitantly, graph theory has been increasingly employed in neuroscience to model the brain's functional connectivity (FC) and to investigate it in a variety of contexts. The aims of this study were: 1) to investigate the reorganization of network topology in the ipsilesional (IL) and contralesional (CL) hemispheres of stroke patients with (motor stroke group) and without (control stroke group) motor impairment, and 2) to predict motor recovery through the relationship between local topological variations of the functional network and increased motor function. We modeled the brain's FC as a graph using fMRI data, and we characterized its interactions with the following graph metrics: degree, clustering coefficient, characteristic path length, and betweenness centrality (BC). For both patient groups, BC yielded the largest variations between the two analyzed time points, especially in the motor stroke group. This group presented significant correlations (P<0.05) between average BC changes and the improvements in upper-extremity Fugl-Meyer (UE-FM) scores at the primary sensorimotor cortex and the supplementary motor area for the CL hemisphere. These regions participate in processes related to the selection, planning, and execution of movement. Generally, higher increases in average BC over these areas were related to larger improvements in UE-FM assessment. Although the sample was small, these results suggest the possibility of using BC as an indication of brain plasticity mechanisms following stroke.

NAA and NAAG variation in neuronal activation during visual stimulation

N-acetyl-aspartyl-glutamate (NAAG) and its hydrolysis product N-acetyl-L-aspartate (NAA) are among the most important brain metabolites. NAA is a marker of neuron integrity and viability, while NAAG modulates glutamate release and may have a role in neuroprotection and synaptic plasticity. Investigating on a quantitative basis the role of these metabolites in brain metabolism in vivo by magnetic resonance spectroscopy (MRS) is a major challenge since the main signals of NAA and NAAG largely overlap. This is a preliminary study in which we evaluated NAA and NAAG changes during a visual stimulation experiment using functional MRS. The paradigm used consisted of a rest period (5 min and 20 s), followed by a stimulation period (10 min and 40 s) and another rest period (10 min and 40 s). MRS from 17 healthy subjects were acquired at 3T with TR/TE = 2000/288 ms. Spectra were averaged over subjects and quantified with LCModel. The main outcomes were that NAA concentration decreased by about 20% with the stimulus, while the concentration of NAAG concomitantly increased by about 200%. Such variations fall into models for the energy metabolism underlying neuronal activation that point to NAAG as being responsible for the hyperemic vascular response that causes the BOLD signal. They also agree with the fact that NAAG and NAA are present in the brain at a ratio of about 1:10, and with the fact that the only known metabolic pathway for NAAG synthesis is from NAA and glutamate.

Depression and anxiety in a community sample with epilepsy in Brazil / Depressão e ansiedade na epilepsia: uma amostra da comunidade no Brasil

OBJECTIVE: To estimate the frequency of depression/anxiety and to establish the social, epilepsy and psychiatric characteristics in individuals with epilepsy. METHOD: A cross-sectional study was employed to evaluate 153 subjects with epilepsy who were identified in a previous community-based survey. First, a structured interview was conducted, followed by a psychiatric evaluation. Subjects with depression were compared to those without, and subjects with anxiety were compared to those without. RESULTS: The prevalence of anxiety and depression was 39.4 and 24.4 percent, respectively. Both were associated with low schooling (OR 3.8, 95 percent CI 1.6 to 9.0 and OR 2.8, 95 percent CI 1.2 to 6.5 for depression and anxiety, respectively), lifetime suicidal thoughts (OR 4.4, 95 percent CI 1.9 to 10.3 and OR 3.6, 95 percent CI 1.7 to 7.7) and lifetime suicide attempts (OR 9.3, 95 percent CI 2.6 to 32.8 and OR 6.9, 95 percent CI 1.8 to 26.4). CONCLUSION: The high rates of depression and anxiety reinforced the need for recognition and treatment of mental disorders in epilepsy.

OBJETIVO: Estimar a frequência de depressão/ansiedade em pessoas com epilepsia e estabelecer as características sociais, da epilepsia e psiquiátricas associadas. MÉTODO: Foi feito um estudo transversal para avaliar 153 sujeitos com epilepsia identificados em um levantamento prévio feito na comunidade. Primeiramente foi realizada uma entrevista estruturada, seguida de uma avaliação psiquiátrica. Os sujeitos deprimidos foram comparados com aqueles sem depressão e os sujeitos com ansiedade foram comparados com aqueles sem ela. RESULTADOS: A prevalência de ansiedade e depressão foi de 39,4 por cento e 24,4 por cento, respectivamente. Ambas foram associadas a baixa escolaridade (OR 3,8; IC95 por cento 1,6-9,0 e OR 2,8, IC95 por cento 1,2- 6,5 para depressão e ansiedade, respectivamente), ideação suicida (OR 4,4; IC95 por cento 1,9-10,3 e OR 3,6; IC95 por cento 1,7-7,7) e tentativa de suicídio (OR 9,3; IC95 por cento 2,6-32,8 e OR 6,9; IC95 por cento 1,8-26,4). CONCLUSÃO: As altas taxas de depressão e ansiedade reforçam a necessidade de reconhecimento e tratamento dos transtornos mentais na epilepsia.

Texture analysis of computed tomography images of acute ischemic stroke patients

Computed tomography (CT) images are routinely used to assess ischemic brain stroke in the acute phase. They can provide important clues about whether to treat the patient by thrombolysis with tissue plasminogen activator. However, in the acute phase, the lesions may be difficult to detect in the images using standard visual analysis. The objective of the present study was to determine if texture analysis techniques applied to CT images of stroke patients could differentiate between normal tissue and affected areas that usually go unperceived under visual analysis. We performed a pilot study in which texture analysis, based on the gray level co-occurrence matrix, was applied to the CT brain images of 5 patients and of 5 control subjects and the results were compared by discriminant analysis. Thirteen regions of interest, regarding areas that may be potentially affected by ischemic stroke, were selected for calculation of texture parameters. All regions of interest for all subjects were classified as lesional or non-lesional tissue by an expert neuroradiologist. Visual assessment of the discriminant analysis graphs showed differences in the values of texture parameters between patients and controls, and also between texture parameters for lesional and non-lesional tissue of the patients. This suggests that texture analysis can indeed be a useful tool to help neurologists in the early assessment of ischemic stroke and quantification of the extent of the affected areas.

Striatal and extrastriatal atrophy in Huntington's disease and its relationship with length of the CAG repeat

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder that affects the striatum most severely. However, except for juvenile forms, relative preservation of the cerebellum has been reported. The objective of the present study was to perform MRI measurements of caudate, putamen, cerebral, and cerebellar volumes and correlate these findings with the length of the CAG repeat and clinical parameters. We evaluated 50 consecutive patients with HD using MRI volumetric measurements and compared them to normal controls. Age at onset of the disease ranged from 4 to 73 years (mean: 43.1 years). The length of the CAG repeat ranged from 40 to 69 (mean: 47.2 CAG). HD patients presented marked atrophy of the caudate and putamen, as well as reduced cerebellar and cerebral volumes. There was a significant correlation between age at onset of HD and length of the CAG repeat, as well as clinical disability and age at onset. The degree of basal ganglia atrophy correlated with the length of the CAG repeat. There was no correlation between cerebellar or cerebral volume and length of the CAG repeat. However, there was a tendency to a positive correlation between duration of disease and cerebellar atrophy. While there was a negative correlation of length of the CAG repeat with age at disease onset and with striatal degeneration, its influence on extrastriatal atrophy, including the cerebellum, was not clear. Extrastriatal atrophy occurs later in HD and may be related to disease duration.

The importance of accurate anatomic assessment for the volumetric analysis of the amygdala

There is a wide range of values reported in volumetric studies of the amygdala. The use of single plane thick magnetic resonance imaging (MRI) may prevent the correct visualization of anatomic landmarks and yield imprecise results. To assess whether there is a difference between volumetric analysis of the amygdala performed with single plane MRI 3-mm slices and with multiplanar analysis of MRI 1-mm slices, we studied healthy subjects and patients with temporal lobe epilepsy. We performed manual delineation of the amygdala on T1-weighted inversion recovery, 3-mm coronal slices and manual delineation of the amygdala on three-dimensional volumetric T1-weighted images with 1-mm slice thickness. The data were compared using a dependent t-test. There was a significant difference between the volumes obtained by the coronal plane-based measurements and the volumes obtained by three-dimensional analysis (P < 0.001). An incorrect estimate of the amygdala volume may preclude a correct analysis of the biological effects of alterations in amygdala volume. Three-dimensional analysis is preferred because it is based on more extensive anatomical assessment and the results are similar to those obtained in post-mortem studies.