Causal relationship between serum uric acid and abnormal blood pressure based on the panel model study: A 5-year cohort study.

BACKGROUND AND AIMS: To investigate the relationship between elevated serum uric acid (SUA) levels and blood pressure (BP). METHODS AND RESULTS: Based on the Beijing Health Management Cohort, 5276 health examination people were enrolled. Cross-lagged model was used to explore the relationship between SUA levels and blood pressure. The results showed: (1) increased SUA and increased systolic blood pressure (SBP): ① The path coefficients from baseline SUA to follow-up SBP were statistically significant in both the general population (ß = 0.034, P < 0.05) and men (ß = 0.048, P < 0.05). The path coefficients from baseline SBP to follow-up SUA were not statistically significant in either the general population (ß = 0.010, P > 0.05) or men (ß = 0.011, P > 0.05). ② The path coefficients from baseline SUA to follow-up SBP and from baseline SBP to follow-up SUA were not statistically significant in women with BMI ≥ 25 kg/m2 and BMI < 25 kg/m2. (2) Increased SUA and diastolic blood pressure (DBP): ① There was no statistical significance between the path coefficients from baseline DBP to follow-up SUA and the path coefficients from baseline SUA to follow-up DBP. ② In men and women, BMI ≥ 25 kg/m2 and BMI < 25 kg/m2, the path coefficients from baseline DBP to follow-up SUA and from baseline SUA to follow-up DBP were not statistically significant. CONCLUSIONS: SUA can increase blood pressure in the general male population; no reverse time sequence relationship was found. The temporal relationships between SUA levels and SBP abnormalities were different in the sex and BMI subgroups. No bidirectional causal temporal relationship was found between SUA elevation and DBP abnormality.

The imported infections among foreign travelers in China: an observational study.

BACKGROUND: In the past few decades, globalization has rendered more frequent and intensive population movement between countries, which has changed the original disease spectrum and brought a huge health impact on the global population including China. This study aims to describe the spectrum and epidemiological characteristics of imported infections among foreign travelers travelling to China. METHODS: The data on imported infections among foreign travelers were obtained from Custom Inbound Screening System (CISS) and the National Notifiable Infectious Disease Reporting System (NNIDRS). All the infections were classified into respiratory, gastrointestinal, vector-borne, blood/sex-transmitted and mucocutaneous diseases, of which case numbers and incidences were calculated and the proportions were compared among subgroups. RESULTS: In total, 17,189 travelers diagnosed with 58 imported infectious diseases were reported from 2014 to 2018, with an overall incidence of 122.59 per million. Respiratory infection (7,351 cases, mainly influenza) and blood/sex-transmitted diseases (6,114 cases mainly Hepatitis B and HIV infection) were the most frequently diagnosed diseases, followed by vector-borne infections (3,128 cases, mainly dengue fever and malaria). The highest case number was from Asia and Europe, while the highest incidence rate was from Africa (296.00 per million). When specific diagnosis was compared, both the highest absolute case number and incidence were observed for influenza. An obvious seasonal pattern was observed for vector-borne diseases, with the annual epidemic spanning from July to November. The origin-destination matrices disclosed the movement of imported infection followed specific routes. CONCLUSIONS: Our study provided a profile of infectious diseases among foreign travelers travelling to China and pinpointed the target regions, seasons and populations for prevention and control, to attain an informed control of imported infections in China.

Effect of Transcranial Alternating Current Stimulation for the Treatment of Chronic Insomnia: A Randomized, Double-Blind, Parallel-Group, Placebo-Controlled Clinical Trial.

BACKGROUND: Not all adults with chronic insomnia respond to the recommended therapeutic options of cognitive behavioral therapy and approved hypnotic drugs. Transcranial alternating current stimulation (tACS) may offer a novel potential treatment modality for insomnia. OBJECTIVES: This study aimed to examine the efficacy and safety of tACS for treating adult patients with chronic insomnia. METHODS: Sixty-two participants with chronic primary insomnia received 20 daily 40-min, 77.5-Hz, 15-mA sessions of active or sham tACS targeting the forehead and both mastoid areas in the laboratory on weekdays for 4 consecutive weeks, followed by a 4-week follow-up period. The primary outcome was response rate measured by the Pittsburgh Sleep Quality Index (PSQI) at week 8. Secondary outcomes were remission rate, insomnia severity, sleep onset latency (SOL), total sleep time (TST), sleep efficiency, sleep quality, daily disturbances, and adverse events at the end of the 4-week intervention and at the 4-week follow-up. RESULTS: Of 62 randomized patients, 60 completed the trial. During the 4-week intervention, 1 subject per group withdrew due to loss of interest and time restriction, respectively. Based on PSQI, at 4-week follow-up, the active group had a higher response rate compared to the sham group (53.4% [16/30] vs. 16.7% [5/30], p = 0.009), but remission rates were not different between groups. At the end of the 4-week intervention, the active group had higher response and remission rates than the sham group (p < 0.001 and p = 0.026, respectively). During the trial, compared with the sham group, the active group showed a statistically significant decrease in PSQI total score, a shortened SOL, an increased TST, improved sleep efficiency, and improved sleep quality (p < 0.05 or p < 0.001). Post hoc analysis revealed that, in comparison with the sham group, the active group had improved symptoms, except for daily disturbances, at the end of the 4-week intervention, and significant improvements in all symptoms at the 4-week follow-up. No adverse events or serious adverse responses occurred during the study. CONCLUSION: The findings show that the tACS applied in the present study has potential as an effective and safe intervention for chronic insomnia within 8 weeks.

The changes of immunoglobulin G N-glycosylation in blood lipids and dyslipidaemia.

BACKGROUND: Alternative N-glycosylation has significant structural and functional consequences on immunoglobulin G (IgG) and can affect immune responses, acting as a switch between pro- and anti-inflammatory IgG functionality. Studies have demonstrated that IgG N-glycosylation is associated with ageing, body mass index, type 2 diabetes and hypertension. METHODS: Herein, we have demonstrated patterns of IgG glycosylation that are associated with blood lipids in a cross-sectional study including 598 Han Chinese aged 20-68 years. The IgG glycome composition was analysed by ultra-performance liquid chromatography. RESULTS: Blood lipids were positively correlated with glycan peak GP6, whereas they were negatively correlated with GP18 (P < 0.05/57). The canonical correlation analysis indicated that initial N-glycan structures, including GP4, GP6, GP9-12, GP14, GP17, GP18 and GP23, were significantly correlated with blood lipids, including total cholesterol, total triglycerides (TG) and low-density lipoprotein (r = 0.390, P < 0.001). IgG glycans patterns were able to distinguish patients with dyslipidaemia from the controls, with an area under the curve of 0.692 (95% confidence interval 0.644-0.740). CONCLUSIONS: Our findings indicated that a possible association between blood lipids and the observed loss of galactose and sialic acid, as well as the addition of bisecting GlcNAcs, which might be related to the chronic inflammation accompanying with the development and procession of dyslipidaemia.

Contourlet-based hippocampal magnetic resonance imaging texture features for multivariant classification and prediction of Alzheimer's disease.

The study is aimed to assess whether the addition of contourlet-based hippocampal magnetic resonance imaging (MRI) texture features to multivariant models improves the classification of Alzheimer's disease (AD) and the prediction of mild cognitive impairment (MCI) conversion, and to evaluate whether Gaussian process (GP) and partial least squares (PLS) are feasible in developing multivariant models in this context. Clinical and MRI data of 58 patients with probable AD, 147 with MCI, and 94 normal controls (NCs) were collected. Baseline contourlet-based hippocampal MRI texture features, medical histories, symptoms, neuropsychological tests, volume-based morphometric (VBM) parameters based on MRI, and regional CMgl measurement based on fluorine-18 fluorodeoxyglucose-positron emission tomography were included to develop GP and PLS models to classify different groups of subjects. GPR1 model, which incorporated MRI texture features and was based on GPG, performed better in classifying different groups of subjects than GPR2 model, which used the same algorithm and had the same data as GPR1 except that MRI texture features were excluded. PLS model, which included the same variables as GPR1 but was based on the PLS algorithm, performed best among the three models. GPR1 accurately predicted 82.2% (51/62) of MCI convertors confirmed during the 2-year follow-up period, while this figure was 53 (85.5%) for PLS model. GPR1 and PLS models accurately predicted 58 (79.5%) vs. 61 (83.6%) of 73 patients with stable MCI, respectively. For seven patients with MCI who converted to NCs, PLS model accurately predicted all cases (100%), while GPR1 predicted six (85.7%) cases. The addition of contourlet-based MRI texture features to multivariant models can effectively improve the classification of AD and the prediction of MCI conversion to AD. Both GPR and LPS models performed well in the classification and predictive process, with the latter having significantly higher classification and predictive accuracies. Advances in knowledge: We combined contourlet-based hippocampal MRI texture features, medical histories, symptoms, neuropsychological tests, volume-based morphometric (VBM) parameters, and regional CMgl measurement to develop models using GP and PLS algorithms to classify AD patients.

BMI and BMI Changes to All-cause Mortality among the Elderly in Beijing: a 20-year Cohort Study.

OBJECTIVE: To explore the association between body mass index (BMI) and all-cause mortality among the elderly in Beijing. METHODS: This analysis was based on the Beijing multidimensional longitudinal study of aging (BLSA), which included 2,090 subjects over 55 years old and was followed-up from 1992 to 2012. BMI-mortality curves were drawn to find the optimal BMI range with the lowest mortality. Cox proportional hazard models were used to obtain the hazard ratios (HRs) for BMI and BMI changes in the overall population and in specific stratified populations. RESULTS: During follow-up, 1,164 deaths were recorded; BMI-mortality curve was U-shaped, with the lowest mortality at a BMI of approximately 25 kg/m2. After adjusting for gender, age, smoking, drinking and some pre-existing diseases, HRs for underweight, overweight and obesity compared with normal weight were 1.372 (95% CI: 1.154-1.631), 0.767 (95% CI: 0.666-0.884) and 0.871 (95% CI: 0.830-1.246), respectively. HR for BMI drop was 3.245 (95% CI: 0.824-12.772) in the underweight group and 1.892 (95% CI: 0.830-1.246) in the normal weight group, HR for BMI rise was 1.795 (95% CI: 1.243-2.591) in normal weight group and 1.962 (95% CI: 1.202-3.203) in the overweight group. CONCLUSION: Keeping BMI in an overweight status and stable is related to a reduced mortality.

Longitudinal Associations between Triglycerides and Metabolic Syndrome Components in a Beijing Adult Population, 2007-2012.

BACKGROUND: Longitudinal associations between triglycerides (TG) and other metabolic syndrome (MetS) components have rarely been reported. The purpose was to investigate the longitudinal association between TG and other MetS components with time. METHODS: The longitudinal study was established in 2007 on individuals who attended health check-ups at Beijing Tongren Hospital and Beijing Xiaotangshan Hospital. Data used in this study was based on 7489 participants who had at least three health check-ups over a period of 5-year follow up. Joint model was used to explore longitudinal associations between TG and other MetS components after adjusted for age. RESULTS: There were positive correlations between TG and other MetS components except for high density lipoprotein (HDL), and the correlations increased with time. A negative correlation was displayed between TG and HDL, and the correlation also increased with time. Among all five pairs of TG and other MetS components, the marginal correlation between TG and body mass index (BMI) was the largest for both men and women. The marginal correlation between TG and fasting plasma glucose was the smallest for men, while the marginal correlation between TG and diastolic blood pressure was the smallest for women. CONCLUSIONS: The longitudinal association between TG and other MetS components increased with time. Among five pairs of TG and other MetS components, the longitudinal correlation between TG and BMI was the largest. It is important to closely monitor subjects with high levels of TG and BMI in health check-up population especially for women, because these two components are closely associated with development of hypertension, diabetes, cardiovascular disease and other metabolic diseases.

Risk Factors of Myopic Shift among Primary School Children in Beijing, China: A Prospective Study.

OBJECTIVE: To evaluate factors associated with myopic shift among primary school children. METHODS: In a one-year prospective school-based study, 5052 children from ten schools were enrolled using a multi-stage random cluster approach. The baseline examination included non-cycloplegic auto-refractometry and questionnaire interview. Measurements were repeated at the follow-up. RESULTS: Among 5052 students at baseline investigated, 4292 students (85.0%) returned for the follow-up examination. The mean refractive error (-1.13±1.57 diopters) had changed -0.52±0.73 diopters from the baseline to the follow-up examination. 2170 (51.0%) had a rate of significant myopic shift (significant myopic shift is defined as the change of spherical equivalent of the refraction ≤ -0.50D between the follow-up and baseline measures). We confirmed that common associated factors (older age, parental myopia, lower refractive status at baseline, shorter reading distance and lower frequency of outdoor activities during class recesses) were associated with greater shift towards myopia. After controlling for age, sex, region of habitation, parental myopia and refractive status at baseline, greater shift towards myopia was independently associated with distance from near-work (OR=1.48 , 95% CI=1.26-1.74, P<0.001) and longer time outdoors for leisure (OR=0.87, 95% CI=0.78-0.97, P<0.013). CONCLUSION: Greater shift towards myopia was independently associated with modifiable factors (distance from near-work and longer time outdoors for leisure) might suggest that encouraging children to go outside for outdoor activities during class recess and after school may be a promising and feasible intervention against myopia development.

Epidemiology of imported infectious diseases, China, 2014-18.

BACKGROUND: The frequent movement of population between countries brings an increasing number of travel-related infections. This study aims to define the spectrum and dynamics of imported infections observed from international travel in the Chinese mainland. METHODS: Sick travellers were screened by inbound sentinel surveillance and post-travel clinic visits from 2014 to 18. The infections were classified as respiratory, gastrointestinal, vector-borne, blood/sexually transmitted and mucocutaneous. The analysed variables included the place of origin of the travellers (Chinese or foreign) and the time when travel-related infection was present (at the time of return, during travel and post-travel visits to the clinic). RESULTS: In total, 58 677 cases were identified amongst 1 409 265 253 travellers, with an incidence of 41.64/million, comprising during-travel incidence of 27.44/million and a post-travel incidence of 14.20/million. Respiratory infections constituted the highest proportion of illnesses during travel (81.19%, 31 393 of 38 667), which mainly came from Asian countries and tourists; with influenza virus and rhinovirus infections being mainly diagnosed. Vector-borne diseases constituted the highest proportion of post-travel illnesses (98.14%, 19 638 of 20 010), which were mainly diagnosed from African countries and labourers; with malaria and dengue fever being mainly diagnosed. The differential infection spectrum varied in terms of the traveller's demography, travel destination and travel purpose. As such, a higher proportion of foreign travellers had blood/sexually transmitted diseases (89.85%, 2832 of 3152), while Chinese citizens had a higher prevalence of vector-borne diseases (85.98%, 19 247 of 22 387) and gastrointestinal diseases (79.36%, 1115 of 1405). The highest incidence rate was observed amongst travellers arriving from Africa, while the lowest was observed amongst travellers arriving from Europe. CONCLUSIONS: The findings might help in preparing recommendations for travellers and also aid in primary care or other clinics that prepare travellers before trips abroad. The findings will also help to identify locations and the associated types of infections that might require attention.

Combination patterns of cardiovascular risks and sequelae at different stage of hypertension in natural hypertensive population in Beijing.

To investigate combination patterns of cardiovascular risks and sequelae at different stages of hypertension, all 6176 newly or previously diagnosed hypertensives were selected from a randomized sampling surveillance data to perform a multiple correspondence analysis. Short duration hypertensives are characterized by relatively young age, less physical exercise, normal fruits and vegetable intakes, high salt diet, and nearly normal blood lipid and glucose. Middle duration hypertensives begin to pursue more physical exercise and less salt, although increasing physiological disorders are found. Severe sequelae such as stroke and myocardial infraction mainly occurred in long duration hypertensives. Results imply that great efforts should be taken in health education and lifestyle interventions on prehypertensive and early stage hypertensive patients.

Spatial and temporal clustering analysis of tuberculosis in the mainland of China at the prefecture level, 2005-2015.

BACKGROUND: Tuberculosis (TB) is still one of the most serious infectious diseases in the mainland of China. So it was urgent for the formulation of more effective measures to prevent and control it. METHODS: The data of reported TB cases in 340 prefectures from the mainland of China were extracted from the China Information System for Disease Control and Prevention (CISDCP) during January 2005 to December 2015. The Kulldorff's retrospective space-time scan statistics was used to identify the temporal, spatial and spatio-temporal clusters of reported TB in the mainland of China by using the discrete Poisson probability model. Spatio-temporal clusters of sputum smear-positive (SS+) reported TB and sputum smear-negative (SS-) reported TB were also detected at the prefecture level. RESULTS: A total of 10 200 528 reported TB cases were collected from 2005 to 2015 in 340 prefectures, including 5 283 983 SS- TB cases and 4 631 734 SS + TB cases with specific sputum smear results, 284 811 cases without sputum smear test. Significantly TB clustering patterns in spatial, temporal and spatio-temporal were observed in this research. Results of the Kulldorff's scan found twelve significant space-time clusters of reported TB. The most likely spatio-temporal cluster (RR = 3.27, P <  0.001) was mainly located in Xinjiang Uygur Autonomous Region of western China, covering five prefectures and clustering in the time frame from September 2012 to November 2015. The spatio-temporal clustering results of SS+ TB and SS- TB also showed the most likely clusters distributed in the western China. However, the clustering time of SS+ TB was concentrated before 2010 while SS- TB was mainly concentrated after 2010. CONCLUSIONS: This study identified the time and region of TB, SS+ TB and SS- TB clustered easily in 340 prefectures in the mainland of China, which is helpful in prioritizing resource assignment in high-risk periods and high-risk areas, and to formulate powerful strategy to prevention and control TB.

[Efficacy and safety of sildenafil therapy in pulmonary artery hypertension: a meta-analysis].

OBJECTIVE: To evaluate the short-term efficacy and safety of sildenafil in treatment of pulmonary artery hypertension (PAH). METHODS: Literatures in regard to sildenafil treatment of PAH were searched in PubMed (from 01/01/1968 to 01/05/2006), Embase (from 1980 to 2006) and China National Knowledge Infrastructure (CNKI) (from 1994 to 2006). Randomized-controlled trials (RCTs) of sildenafil versus placebo in the treatment of PAH were conducted. The quality of the included trials was evaluated by two reviewers independently. Meta-analysis was done by using the Cochrane Collaboration's RevMan 4.2.8. RESULTS: Ten literatures were retrieved. Four RCTs, including 328 patients, were included and were graded in terms of the quality of randomization, allocation, concealment and blinding. One study was graded as level A and the other three were graded as level B. The meta-analysis showed that compared with placebo treatment, sildenafil therapy can (1) improve the exercise capacity of the PAH patients measured as distance covered in a 6 minute walk test with an increase of 55.76 meters on average in 6 minutes' walk (95% confidence interval, 41.26 to 70.25; P < 0.01), (2) increase the exercise time of the PAH patients by 221.13s on average (95% confidence interval, 146.13 to 296.14; P < 0.01), (3) decrease the pulmonary artery systolic pressure by 11.51 mmHg on average (95% confidence interval, 1.41 to 21.60, P = 0.03), and (4) alleviate the exacerbation of clinical conditions with a total odds ratio (OR) of 0.36 (95% confidence interval, 0.16 to 0.78, P = 0.01); however, it failed to alleviate the headache and hypotension in comparison with the placebo group. No sexual disturbance was seen in the patients treated with sildenafil. CONCLUSION: Sildenafil therapy improves the clinical symptoms and exercise capacity, and decreases the pulmonary artery systolic pressure of the PAH patients; and causes no serious side effects.

Association of Waist Circumference Gain and Incident Prediabetes Defined by Fasting Glucose: A Seven-Year Longitudinal Study in Beijing, China.

The risk of incident prediabetes with gain in waist circumference (WC) has not been addressed among Chinese adults. A total of 7951 participants who underwent health check-ups at the Beijing Physical Examination Center and Beijing Xiaotangshan hospital were recruited in 2009 and followed up in 2016. Participants were classified into four groups according to categories of percent WC gain: ≤-2.5%, -2.5-2.5%, 2.5-5%, and >5%. The effect of WC gain on prediabetes was evaluated using modified Poisson regression models. Over seven years of follow-up, we identified 1034 prediabetes cases (413 women). Compared with a WC gain of ≤-2.5%, participants with a WC gain of >5% have a higher risk of prediabetes, be they male (non-abdominal obesity at baseline group: RR = 1.57, 95% CI: 1.10-2.24, abdominal obesity at baseline group: RR = 1.66, 95% CI: 1.20-2.30) or female (non-abdominal obesity at baseline group: RR = 1.74, 95% CI: 1.14-2.64, abdominal obesity at baseline group: RR = 2.47, 95% CI: 1.43-4.28). In conclusion, the risk of prediabetes increased significantly with increasing WC for both genders in the Chinese population. Lifestyle interventions aiming at preventing abdominal obesity are urgently needed to reduce the increasing burden of prediabetes, diabetes, and its complications.

Education-Related Parameters in High Myopia: Adults versus School Children.

PURPOSE: Since high myopia in the younger generation may differ etiologically from high myopia in older generations, we examined whether education-related parameters differ between high myopia in today´s school children and high pathological myopia in today´s elderly generation. METHODS: The investigation included the adult populations of the population-based Beijing Eye Study (BES) (3468 adults;mean age:64.6±9.8years;range:50-93years) and Central India Eye and Medical Study (CIEMS) (4711 adults;age:49.±13.2years;range:30-100years), and the children and teenager populations of the Shandong Children Eye Study (SCES) (6026 children;age:9.7±3.3years;range:4-18years;cycloplegic refractometry), Gobi Desert Children Eye Study (1565;age:11.9±3.5years;range:6-21 years;cycloplegic refractometry), Beijing Pediatric Eye Study (681 children;age:7.7±1.6years;range:5-13 years;non-cycloplegic refractometry,calculation of axial length to corneal curvature radius ratio), Beijing Children Eye Study (15066 children;age:13.2±3.4years;range:7-18years;non-cycloplegic refractometry), Beijing High School Teenager Eye Study (4677 children;age:16.9±0.7years;range:16-18years;non-cycloplegic refractometry). RESULTS: In the BES and CIEMS, educational level did not differ significantly between, or was significantly lower in the highly myopic group (myopic refractive error ≥6 diopters) than in the non-highly myopic group. In all non-adult study populations, higher prevalence of high myopia was significantly associated with higher degree of education related parameters such as attendance of high-level schools, and more time spent for indoors near work versus time spent outdoors. CONCLUSIONS: Comparing associations of old or genetic high myopia in adults with new or acquired high myopia in school children revealed that education-related parameters did not show a clear association with old or genetic high myopia, while in contrast, new high myopia showed strong associations with education. It confirms previous studies that the two forms of high myopia not only differed in age of onset, but also in associations with education as well. The data support the notion of two types of high myopia. Future studies may assess whether the risk of pathologic myopic maculopathy and high myopia associated open-angle glaucoma differs between both types of high myopia.

Relationship between dietary behaviors and risk of noncommunicablediseases among adults in Beijing / 预防医学

Objective@#To evaluate the effects of dietary behaviors on the risk of hypertension, diabetes and cardiovascular diseases.@*Methods@#A total of 12 208 subjects aged 18-60 years old were investigated by questionnaires to collect demographic data, dietary behaviors and lifestyle information, when they did health examination in a tertiary hospital in Beijing from 2014 to 2019. During the observation period of five year, the incidence of hypertension, diabetes and cardiovascular diseases were collected through health examination files every year. The multivariate logistic regression model was employed to analyze the associations of dietary behaviors with hypertension, diabetes and cardiovascular diseases. @*Results@#The study included 6 218 ( 50.93% ) males and 5 990 ( 49.07% ) females. The cumulative incidence rates of hypertension, diabetes and cardiovascular diseases were 7.75%, 2.72% and 3.49%, respectively. The multivariate logistic regression analysis indicated that the high-sodium diet ( OR=1.422, 95%CI: 1.191-1.697 ) , eating fast ( OR=1.457, 95%CI: 1.102-1.974 ), eating more refined grain ( OR=1.251, 95%CI: 1.050-1.490 ) and drinking milk less than once a week ( OR=1.316, 95%CI: 1.022-1.697 ) were risk factors for hypertension. The high-sodium diet ( OR=1.344, 95%CI: 1.048-1.725 ), eating fast ( OR=1.733, 95%CI: 1.046-2.871 ), eating more meat ( OR=1.651,95%CI: 1.263-2.158 ) were risk factors for diabetes. High-sodium diet ( OR=1.501, 95%CI: 1.192-1.889 ) was risk factors for cardiovascular disease. @*Conclusion@#The diet with high sodium, more meat and refined grain as well as eating fast can increase the risk of hypertension, diabetes and cardiovascular diseases.

Prevalence and associated factors of myopia in high-school students in Beijing.

PURPOSE: To evaluate prevalence and associated factors for myopia in high school students in Beijing. METHODS: Grade 10 and 11 high school students were randomly selected from nine randomly selected districts of Beijing. The students underwent non-cylcoplegic auto-refractometry and an interview. RESULTS: Out of 4798 eligible students, 4677 (93.4%) students (mean age:16.9±0.7years;range:16-18 years) participated. Mean refractive error of right eyes and left eyes was -2.78±2.29 diopters and -2.59±2.50 diopters, respectively. Prevalence of myopia (defined as ≤ -1.00 diopters in the worse eye) was 80.7% (95% Confidence Interval (CI): 79.6-81.8%). Out of 3773 students with myopia, 1525 (40.4%) wore glasses daily. In multiple logistic regression analysis, a higher prevalence of myopia was associated with female sex (odds ratio (OR) = 1.31;95%CI:1.11-1.55), Han ethnicity (OR = 1.64;95%CI:1.28-2.11), attending key schools (OR = 1.48;95%CI:1.24,1.77), higher family income (OR = 1.37;95%CI:1.09-1.71), longer time spent for near work (OR = 1.43;95%CI:1.06-1.93), shorter near work distance (OR = 1.87;95%CI:1.55-2.26), lower frequency of active rest during studying (OR = 1.40;95%CI:1.16-1.70), and parental myopia (OR = 2.28;95%CI:1.80-2.87). The interaction between distance from near work and time spent for near work was statistically (P = 0.03) significant. In multiple logistic regression analysis, higher prevalence of high myopia (≤-6.0 diopters) was associated with studying in key schools (OR = 1.38;95%CI:1.05,1.81), lower frequency of active rest during studying (OR = 1.40;95%CI:1.09,1.79), and a higher number of myopic parents (OR = 2.66;95%CI:2.08,3.40). CONCLUSIONS: A prevalence of about 80% for myopia and a prevalence of about 10% for high myopia in students aged 16 to 18 years and attending classes of grade 10 and 11 in a Chinese metropolitan region is another example of the high prevalence of moderate and high myopia in metropolitan areas of China. With this young myopic generation getting older, myopia as cause for visual impairment and blindness may further increase in importance. Future studies may address whether active rests during studying with looking into the distance are preventive against myopia development or progression.

Association of hematological parameters with metabolic syndrome in Beijing adult population: a longitudinal study.

The purposes of the study were to estimate the incidence of metabolic syndrome (MetS) and to systematically evaluate the relationship between hematological parameters and MetS in a 5-year follow-up of Beijing adult population. The longitudinal study included 3,180 adults, aged 20-65 years, who attended health check-ups in Beijing Tongren Hospital in 2007 and 2012. Multivariate logistic regression was conducted to explore the associations between hematological parameters and MetS. The 5-year cumulative incidence of MetS in this sample was 10.82 % (14.22 % for males and 7.59 % for females). Among all the hematological parameters, white blood cell count (WBC) was positively associated with MetS for 20-35-year-old (male OR 1.482, 95 % CI 1.169-2.974; female OR 1.398, 95 % CI 1.145-3.011), and 36-50-year-old (male OR 2.012, 95 % CI 1.290-4.010; female OR 3.400, 95 % CI 1.818-4.528) male and female subjects. Alanine aminotransferase (ALT) was significantly associated with the incidence of MetS for males (20-35-year-old OR 2.080, 95 % CI 1.371-3.159; 36-50-year-old OR 2.421, 95 % CI 1.335-3.412; 51-65-year-old OR 4.267, 95 % CI 1.161-6.781). Low-density lipoprotein cholesterol (LDL-C) was positively associated with MetS for 51-65-year-old (male OR 3.078, 95 % CI 2.468-5.131; female OR 2.140, 95 % CI 1.524-4.359) for male and female subjects. WBC is positively associated with MetS for young adults, while LDL-C is positively associated with MetS for elderly people. ALT is positively associated with MetS for males. Our findings provide further evidence in support of using hematological markers for early detection of individuals at risk for MetS.

Prevalence of myopia in school children in greater Beijing: the Beijing Childhood Eye Study.

PURPOSE: To determine the prevalence of myopia in school children in Greater Beijing. METHODS: The Beijing Childhood Eye Study was a school-based cross-sectional study. One school of each level (primary, junior high, senior high) was randomly selected from nine randomly selected districts of Greater Beijing. The children underwent non-cycloplegic refractometry and their parents an interview. RESULTS: Of 16 771 eligible students, 15 066 (89.8%) children with a mean age of 13.2 ± 3.4 years (range: 7-18 years) participated. Prevalence of myopia defined as refractive error of ≤-0.50 diopters (D), ≤-1.00 D, ≤-6.00 D and ≤-8.00 D in the right eye was 64.9 ± 0.4%, 53.0 ± 0.4%, 4.3 ± 0.2% and 1.0 ± 0.1% respectively. In multivariate analysis, prevalence of myopia was significantly (p < 0.001) associated with higher age, female gender, urban region and school type. Prevalence of myopia of ≤-1.00 D and of ≤-8.0 D increased from 9.7% and 0% in 7 year olds, respectively, to 74.2% and 1.8% in 17- or 18 year olds respectively. The latter figure was already similar (p = 0.39) to the prevalence of high myopia in the elderly Beijing Eye Study population (1.6%). In a subset of 1082 children undergoing cycloplegia, difference in refractive error between prior to and after cycloplegia was 0.31 ± 0.47 diopters. CONCLUSIONS: On the basis of previous investigations from China, our study indicated an ongoing myopic shift in the young generation. Since the prevalence of high myopia in children aged 17 or 18 years was already similar to the one in the elderly Beijing population, the data prognosticate an increase in vision threatening high myopia in the future adult population.

Risk profiles for metabolic syndrome and its transition patterns for the elderly in Beijing, 1992-2009.

There have been few reports on the development of metabolic disorders, especially when they are considered as a cluster. The purpose of this study was to describe risk profiles for metabolic syndrome (MetS) in elderly dwellers in Beijing, and to find their transition patterns over time. Data were derived from Beijing longitudinal study of aging, a community-based cohort study hosted by Xuanwu hospital. There were 3,257 elderly people aged 55 years or over recruited in 1992. MetS was assessed for the years 1992, 2000, and 2009. Finally, 363 subjects with complete information for components of MetS in the three years were included in the study. The criteria of MetS recommended by the joint interim statement criteria were adopted. Latent transition analysis was used to calculate the transition probabilities between adjacent visits. A risk typology consisting of four time-invariant groups was detected based on the components of MetS for all subjects. Low MetS risk group, BP risk group, BP-HDL risk group, and BP-FPG-TG risk group were found. The probability of staying at the same status was higher at the two intervals across 18 years. Four latent groups were extracted based on three assessments for the components of MetS, together with their transition patterns. Findings suggested various trajectories for MetS components. Different combinations of intervention strategy might be needed for MetS risk groups.

Prediction models for solitary pulmonary nodules based on curvelet textural features and clinical parameters.

Lung cancer, one of the leading causes of cancer-related deaths, usually appears as solitary pulmonary nodules (SPNs) which are hard to diagnose using the naked eye. In this paper, curvelet-based textural features and clinical parameters are used with three prediction models [a multilevel model, a least absolute shrinkage and selection operator (LASSO) regression method, and a support vector machine (SVM)] to improve the diagnosis of benign and malignant SPNs. Dimensionality reduction of the original curvelet-based textural features was achieved using principal component analysis. In addition, non-conditional logistical regression was used to find clinical predictors among demographic parameters and morphological features. The results showed that, combined with 11 clinical predictors, the accuracy rates using 12 principal components were higher than those using the original curvelet-based textural features. To evaluate the models, 10-fold cross validation and back substitution were applied. The results obtained, respectively, were 0.8549 and 0.9221 for the LASSO method, 0.9443 and 0.9831 for SVM, and 0.8722 and 0.9722 for the multilevel model. All in all, it was found that using curvelet-based textural features after dimensionality reduction and using clinical predictors, the highest accuracy rate was achieved with SVM. The method may be used as an auxiliary tool to differentiate between benign and malignant SPNs in CT images.