Zixing Wang

Detection and size measurements of pulmonary nodules in ultra-low-dose CT with iterative reconstruction compared to low dose CT.

BACKGROUND In this study, the accuracy of ultra-low-dose computed tomography (CT) with iterative reconstruction (IR) for detection and measurement of pulmonary nodules was evaluated. METHODS Eighty-four individuals referred for lung cancer screening (mean age: 54.5±10.8 years) underwent low-dose computed tomography (LDCT) and ultra-low-dose CT. CT examinations were performed with attenuation-based tube current modulation. Reference tube voltage and current were set to 120kV/25mÅs for LDCT and 80kV/4mÅs for ultra-low-dose CT. CT images were reconstructed with filtered back projection (FBP) for LDCT, and with FBP and IR for ultra-low-dose CT datasets. A reference standard was established by a consensus panel of 2 different radiologists on LDCT. Volume and diameter of the solid nodules were measured on LDCT with FBP and ultra-low dose CT with FBP and IR. Interobserver and interscan variability were analyzed and compared by the Bland-Altman method. RESULTS A total of 127 nodules were identified, including 105 solid nodules, 15 part solid nodules, 7 ground glass nodules. On ultra-low-dose CT scans, the effective radiation dose was 0.13±0.11mSv. A total of 113 (88.9%) and 110 (86.6%) true-positive nodules with FBP versus 117 (92.1%) and 118(92.9%) with IR were detected by two observers, respectively. The volume and size of the 105 solid nodules were measured, with mean volume/diameter of 46.5±46.6 mm(3)/5.1±1.6mm. There was no significant difference in nodule volume or diameter measurements between ultra-low-dose CT and LDCT protocols for solid nodules. CONCLUSIONS Ultra-low-dose CT with iterative reconstruction has high sensitivity for lung nodule detection without significant difference in nodule size and volume measurement compared to LDCT.

Influence of Salt Intake on Association of Blood Uric Acid with Hypertension and Related Cardiovascular Risk.

Background A relationship of blood uric acid (UA) with hypertension and cardiovascular risk is under debate thus salt intake is hypothesized to contribute to such associations. Methods In this cross-sectional study, stratified cluster random sampling elicited a sample of 1805 Kazakhs with 92.4% compliance. Hypertension and moderate-or-high total cardiovascular risk (mTCR) were defined according to guidelines. Sodium intake was assessed by urinary sodium excretion. Prevalence ratios (PRs) were used to express associations of UA with hypertension and mTCR. Results In the highest tertile of sodium intake in women, the adjusted PRs (95% confidence intervals) of low to high quartiles compared with the lowest quartile of UA, were 1.22(0.78–1.91), 1.18(0.75–1.85), and 1.65(1.09–2.51) for hypertension and 1.19(0.74–1.90), 1.39(0.91–2.11), and 1.65(1.10–2.47) for mTCR (P for trend <0.05). However, these findings were not shown for other sodium intake levels. There were similar results in men. PRs markedly increased with a concomitant increase in UA and sodium intake and there was a significant interaction (P = 0.010) for mTCR with PRs of 1.69(1.10–2.60) for men and 3.70(2.09–6.52) for women in those with the highest compared with the lowest quartile of UA and tertile of sodium intake. Similar findings were shown for hypertension. Conclusions This study implied that a high salt intake may enhance the associations of UA with hypertension and cardiovascular risk.

Prevalence of conventional cardiovascular disease risk factors among Chinese Kazakh individuals of diverse occupational backgrounds in Xinjiang China.

Kazakh is a typical transnational ethnic group with the Eurasian lineage. It is the main ethnic group in Kazakhstan, and one of the ethnic minorities in China, Russia, Turkeymore than 40 other countries and regions. There are an approximately 1.25 million Kazak populations in China, of which 96.4% is located in northern Xinjiang [1]. For thousands of years, Chinas Kazakh people are mainly active in raising livestock on the prairie grasslands.With the development of the urbanization, Kazak people naturally formed three different subgroups with different occupation backgrounds (i.e., nomads, farmers, and urban residents). When cardiovascular disease (CVD) risk factors are more prevalent in urban China, little is known about the prevalence about this ethnic group. To investigate the prevalence of CVD conventional risk factors among Kazakh individuals of different occupational backgrounds the baseline data of The Xinjiang Altay Kazakh Heart Study (XAKHS) was used.

Can CT Screening Give Rise to a Beneficial Stage Shift in Lung Cancer Patients? Systematic Review and Meta-Analysis.

Objectives To portray the stage characteristics of lung cancers detected in CT screenings, and explore whether there’s universal stage superiority over other methods for various pathological types using available data worldwide in a meta-analysis approach. Materials and Methods EMBASE and MEDLINE were searched for studies on lung cancer CT screening in natural populations through July 2015 without language or other filters. Twenty-four studies (8 trials and 16 cohorts) involving 1875 CT-detected lung cancer patients were enrolled and assessed by QUADAS-2. Pathology-confirmed stage information was carefully extracted by two reviewers. Stage I or limited stage proportions were pooled by random effect model with Freeman-Tukey double arcsine transformation. Results Pooled stage I cancer proportion in CT screenings was 73.2% (95% confidence interval: 68.6%, 77.5%), with a significant rising trend (Ptrend<0.05) from baseline (64.7%) to ≥5 repeat rounds (87.1%). Relative to chest radiograph and usual care, the increased stage I proportions in CT were 12.2% (P>0.05), and 46.5% (P<0.05), respectively. Pathology-specifically, adenocarcinomas (66%) and squamous cell lung cancers (17%) composed the majority of CT-detected lung cancers, and had significantly higher stage I proportions relative to chest radiograph (bronchioloalveolar adenocarcinomas, 80.9% vs 51.4%; other adenocarcinomas, 58.8% vs 38.3%; squamous cell lung cancers, 52.3% vs 38.3%; all P<0.05). However, the percentage of small cell lung cancer was lower using CT than other detection routes, and no significant difference in limited stage proportion was observed (6.8% vs 10.8%, P>0.05). Conclusion CT screening can detect more early stage non-small cell lung cancers, but not all of them could be beneficial as there are a considerable number of indolent ones such as bronchioloalveolar adenocarcinomas. Still, current evidence is lacking regarding small cell lung cancers.

Multicentre evaluation of perioperative red blood cells transfusions in China

Multicentre evaluation of perioperative red blood cells transfusions in China Editor—China is facing a blood shortage. Approximately 60% of blood products are being transfused during clinical surgery. We aimed to assess the appropriateness of perioperative red blood cells (RBCs) transfusion in public tertiary general hospitals in China. This study was designed as a retrospective (January 2006– December 2009) multicentre survey involving three typical sample hospitals [The Peking Union Medical College Hospital (PUMC Hospital), the Second Affiliated Hospital of Zhejiang University School of Medicine (SAZU Hospital), and the Northern Jiangsu People’s Hospital (NJP Hospital)]. Using a yearstratified random sampling with a sampling proportion of 20% for every stratum, 6384 patients who had a history of RBCs transfusion were selected from three hospitals. Of them, 1274 patients, who had complete records of objective indication, were included in the appropriateness evaluation. A structural survey form was used to extract data from the medical records, which included the patients’ general information, surgical information, objective transfusion indication, and blood infusion information. The appropriateness evaluation consisted of two steps. First, a reasonableness evaluation was done by a composite criterion that was mainly based on Chinese blood transfusion guidance. – 6 Then, over-transfusion was further assessed among patients who were identified as reasonable transfusion based on the first step. During the study periods, the whole blood transfusion was almost replaced by blood component transfusion after the year 2007. The proportion of blood component transfusion increased from 92.3% in 2006 to 99.6% in 2009. Overall, the unreasonable RBCs transfusion rate significantly decreased from 41.5% [95% confidence interval (CI): 35.2– 47.9] to 30.2% (25.9–34.7) during the study periods. The downtrends were consistent in all subgroups (38.7–28.8%, 45.2–23.5%, and 41.9–38.9% at the PUMC, the SAZU, and the NJP Hospital, respectively, all P,0.05). Table 1 shows the distribution characteristics of patients who have undergone unreasonable RBCs transfusions. The unreasonable rate in thoracic surgery patients was highest [56.8% (46.3–67.0)], followed by heart/blood vessel surgery patients [47.7% (39.7–55.9)]. Patients without anaemia on admission had more than twice the unreasonable rate as did anaemia patients, especially at the SAZU (64.7% vs 17.9%, P,0.0001) and the NJP Hospital (68.7% vs 24.2%, P,0.0001). In fact, when surgical acute blood loss was replaced by crystalloid or colloid fluids to maintain normovolaemia, in most stable hospitalized patients with adequate preoperative haemoglobin, the loss could often be well tolerated due to normal compensatory responses that are invoked before a blood transfusion becomes necessary. 5 Overall, the over-transfusion rate was 10.1%. Nearly, half of the over-transfusion episodesoccurred inabdominal operations (consistently in three hospitals). Abdominal surgery accounted for the highest proportion ofall surgeries (37.6%)and consumed the largest number of RBCs transfusions (38.4%). Improved transfusion practices during abdomen surgery might conserve scarce blood resources largely because of its substantial operation quantity. After controlling for the hospital, the overtransfusion rate in patients without anaemia on admission was significantly higher than that in anaemic patients (16.9% vs 6.8%, P,0.0001). This study suggests that perioperative blood transfusion is gradually being standardized in China. However, rational blood usage still requires improvements. The low proportion of patients who have complete indication records indicated that an objective indication-guided blood transfusion needs to be further strengthened. Patients who had undergone thoracic, abdominal surgery, or without anaemia on admission were considered as potential populations for blood conservation. Our resultsare unlikely to beconclusive because of the typical sampling design. Nevertheless, these data have sounded alarm bells for perioperative blood conservation in China.

Prevalence, Awareness, Treatment, and Control of Hypertension among Kazakhs with high Salt Intake in Xinjiang, China: A Community-based Cross-sectional Study

Hypertension is a leading cause of death worldwide; data on hypertension among ethnic minorities in China are sparse. This study aimed to estimate hypertension prevalence, awareness, treatment, and control in a Kazakh population, and to assess the association between salt intake and the above measures. A cross-sectional survey was conducted among Kazakh adults (≥30 years old) in the town of Hongdun, Altay, Xinjiang. Survey procedures included a questionnaire, physical measurement, and laboratory tests. Of 1805 eligible individuals, 1668 (92.4%) were included in the analysis. After adjustment for gender, age, and occupation, prevalence of hypertension was 45.5%. The proportions with awareness, treatment, control, or medication-control were 61.0%, 28.8%, 2.9% and 10.1%, respectively. Higher prevalence was seen among nomads and farmers (50.7% and 44.6%, respectively). However, the proportions with treatment or control were lower than seen among urban citizens. Hypertension prevalence was higher in those with higher salt intake (p = 0.0008). In contrast, the proportions with awareness (p = 0.0389), treatment (p = 0.0010), control (p = 0.0503), and medication-control (p = 0.2012) reduced as salt intake increased. In conclusion, hypertension prevalence is high in this population, but the proportions with awareness, treatment, or control are sub-optimal. Public health interventions that improve hypertension prevention and control, particularly among nomads, is needed.

Passive smoking and stroke in men and women: a national population-based case-control study in China

An association between passive smoking and stroke is unclear in China, particularly the association with hemorrhagic stroke. This study included 16205 deaths due to stroke aged ≥30 years and 16205 non-stroke controls randomly selected and frequency-matched to cases on gender and age. Smoking of spouses, defined as ≥1 cigarette per day for up to 1 year, was taken as a measure of exposure to passive smoking of subjects that was retrospectively ascertained by interviewing surviving spouses. After adjustment for variables, passive smoking increased the risk of death by 10% (odds ratio (OR), 1.10; 95% confidence interval (CI), 1.05–1.16) for all strokes, by 10% (OR, 1.10; 95% CI, 1.04–1.16) for hemorrhagic stroke, and by 12% (OR, 1.12; 95% CI, 1.03–1.23) for ischemic stroke, compared with non-exposure. This finding was highly consistent in men or women and in smokers or non-smokers, and was generally consistent among zones of China despite geographic diversity. The risk significantly increased with exposure-years and quantity of cigarettes smoked daily by spouses. This study indicated that passive smoking is associated with deaths from all-type strokes. It is highly advisable for the government to promote strong tobacco prevention and cessation programs and smoke-free environments.

Smoking and adult glioma: a population-based case-control study in China

BACKGROUND Smoking increases the risk of numerous cancers; however, an association of smoking with adult gliomas has not been found in a population. METHODS This case-control study included 4556 glioma cases (ICD-9 code 191.0-191.9) aged ≥ 30 years and 9112 controls from a national survey of smoking and mortality in China in 1989-1991. Controls from 325 255 surviving spouses of all-cause deaths were randomly assigned to cases in each of 103 areas according to sex and age groups at a ratio of 2:1. Smoking information was ascertained retrospectively by interviewing surviving spouses. RESULTS After adjustment for confounders, smoking increased the risk of glioma deaths by 11% (odds ratio [OR] = 1.11; 95% confidence interval [CI]: 1.03-1.21). Compared with non-smokers; the increased risk was 9% (OR = 1.09; 95% CI: 0.99-1.20) in men and 16% (OR = 1.16; 95% CI: 1.00-1.36) in women. The risk increased with age and doses. For individuals aged ≥ 50 years, smoking was associated with higher risk of glioma death by 25% (OR = 1.25; 95% CI: 1.15-1.38); this increased risk for smokers who smoked ≥ 20 cigarettes daily for ≥ 30 years was 53% (OR = 1.53; 95% CI: 1.34-1.74). There were similar findings in both men and women and with either pathology-based or non-pathology-based comparisons. CONCLUSIONS This study indicates that smoking is associated with glioma deaths in the Chinese population. Long-term heavy smoking could be a factor for risk stratification in individuals attending brain tumor clinics.

Quantitative assessment of Pulmonary Alveolar Proteinosis (PAP) with ultra-dose CT and correlation with Pulmonary Function Tests (PFTs)

Background The purpose of this study was to investigate whether ultra-low-dose chest computed tomography (CT) can be used for visual assessment of CT features in patients with pulmonary alveolar proteinosis (PAP) and to evaluate the relationship between the quantitative analysis of the ultra-low-dose CT scans and the pulmonary function tests (PFTs). Methods Thirty-eight patients (mean [SD] age, 44.47 [12.28] years; 29 males, 9 females) with PAP were enrolled and subjected to two scans each with low-dose CT (reference parameters: 120 kV and 50 mAs) and ultra-low-dose CT (reference parameters, 80 kV, 25 mAs). Images were reconstructed via filtered back projection (FBP) for low-dose CT and iterative reconstruction (IR) for ultra-low-dose CT. All patients underwent PFT. The Visual analysis for ground glass opacity (GGO) is performed. The quantitative CT and PFT results were analyzed by canonical correlations. Results The mean body mass index (BMI) was 25.37±3.26 kg/m2. The effective radiation doses were 2.30±0.46 and 0.24±0.05 mSv for low-dose and ultra-low-dose CT, respectively. The size-specific dose estimates were 5.81±0.81 and 0.62±0.09 mSv for low-dose and ultra-low-dose CT. GGOs and interlobular septal thickening were observed bilaterally in all patients. The average visual GGO score was lower in the upper field (2.67±1.24) but higher in the middle and lower fields (3.08±1.32 and 3.08±0.97, respectively). The average score for the whole lung was 2.94±1.19. There is a significant correlation between PFTs and quantitative of ultra-low-dose CT (canonical loading = 0.78). Conclusions Ultra-low-dose CT has the potential to quantify the lung parenchyma changes of PAP. This technique could provide a sensitive and objective assessment of PAP and has good relation with PFTs. In addition, the radiation dose of ultra-low-dose CT was very low.