Xiaohua Ye

Dose–Risk and Duration–Risk Relationships between Aspirin and Colorectal Cancer: A Meta-Analysis of Published Cohort Studies

Background In previous meta-analyses, aspirin use has been associated with reduced risk of colorectal cancer. However, uncertainty remains on the exact dose–risk and duration–risk relationships. Methods We identified studies by searching several English and Chinese electronic databases and reviewing relevant articles. The dose-response meta-analysis was performed by linear trend regression and restricted cubic spline regression. Subgroup analyses were conducted to explore possible heterogeneity among studies. Potential heterogeneity was calculated as Q statistic and I 2 value. Publication bias was evaluated using funnel plots and quantified by the Begg’s and Egger’s test. Results Twelve studies were included in this meta-analysis. An inverse association between aspirin use and colorectal cancer was observed in both the overall group (RR = 0.74, 95% CI 0.64–0.83 for aspirin dose; RR = 0.80, 95% CI 0.75–0.85 for frequency of aspirin use; RR = 0.75, 95% CI 0.68–0.81 for years of aspirin use) and subgroups stratified by sex and cancer site. The dose-response meta-analysis showed that there was a 20% statistically significant decreased risk of colorectal cancer for 325 mg aspirin per day increment, 18% decreased risk for 7 times aspirin per week increment and 18% decreased risk for 10 years aspirin increment. Conclusion Long-term (>5 years), low-dose (75–325 mg per day) and regular aspirin use (2–7 times per week) can effectively reduce the risk of colorectal cancer.

Comparison of Efficacy and Safety of Tenofovir and Entecavir in Chronic Hepatitis B Virus Infection: A Systematic Review and Meta-Analysis

Objective Tenofovir (TDF) and entecavir (ETV) are both potent antiviral agents for the treatment of chronic hepatitis B virus (HBV) infection. Multiple studies have compared efficacy and safety of these two agents, but yielded inconsistent results. Hence, we conducted a meta-analysis to discern comparative efficacy and safety. Methods Published data relevant to a comparison of TDF and ETV used in HBV were included. HBV DNA suppression rate, ALT normalization rate, and HBeAg seroconversion rate at 24 weeks and 48 weeks were reviewed. Drug safety profiles and resistance were also discussed. Results Seven articles met entry criteria. Four and six articles included data for 24 and 48-week HBV DNA suppression rates, respectively, and no significant differences for the rates between the two drugs were found in chronic HBV patients (TDF vs. ETV: relative risk [RR] = 1.10, 95% CI = 0.91–1.33 and RR = 1.07, 95% CI = 0.99–1.17 for 24 weeks and 48 weeks, respectively). For the ALT normalization rate (three studies for 24 weeks, four articles for 48 weeks) and HBeAg seroconversion rate (two and four studies for 24 weeks and 48 weeks, respectively), no difference was observed between TDF and ETV. Additionally, no significant distinction in short term safety was found for CHB patients. Conclusions TDF and ETV are similarly effective and safe in chronic HBV patients after 24 weeks and 48 weeks of anti-viral therapy. Nevertheless, the long-term efficacy and safety of TDF and ETV should be monitored in prolonged therapy.

Frequency-risk and duration-risk relationships between aspirin use and gastric cancer: a systematic review and meta-analysis.

Background Although previous meta-analyses have suggested an association between aspirin use and risk of gastric cancer, current evidence is inconsistent. Additionally, it remains unclear whether there are frequency-risk and duration-risk relationships and if a threshold of effect exists. Methods We identified studies by searching MEDLINE and PUBMED databases and reviewing relevant articles. We derived the summary risk estimates using fixed-effects or random-effects model based on homogeneity analysis. The dose-response meta-analysis was performed by linear trend regression and restricted cubic spline regression. Potential heterogeneity was tested using the Q statistic and quantified with the I 2 statistic. Subgroup analyses and Galbraith plots were used to explore the potential sources of heterogeneity. Publication bias was evaluated with funnel plots and quantified by the Beggs and Eggers test. Results Fifteen studies were included in this meta-analysis. There was an overall 29% reduced risk of gastric cancer corresponding to aspirin use (RR  = 0.71, 95% CI 0.60–0.82). We found there are nonlinear frequency-risk and linear duration-risk relations between aspirin use and gastric cancer. A monotonically decreasing relation was observed only for low-frequency (≤4.5 times/week) aspirin intake (10% decreased risk for once/week, 19% for twice/week and 29% for 4.5 times/week), and the frequency threshold of aspirin use is 4.5 times per week. Regarding those with duration of aspirin use, there was a tendency towards stronger risk reduction of gastric cancer for longer aspirin use (10% decreased risk for 4 years, 19% for 8 years and 28% for 12 years), and no duration threshold was observed. Conclusion Our findings suggest that long-term (≥4 years) and low-frequency (1–4.5 times per week) aspirin use is associated with a statistically significant, dose-dependent reduction in the risk of gastric cancer.

The Efficacy and Safety of Linezolid and Glycopeptides in the Treatment of Staphylococcus aureus Infections

To assess the effectiveness and safety of linezolid in comparison with glycopeptides (vancomycin and teicoplanin) for the treatment of Staphylococcus aureus infections, we conducted a meta-analysis of relevant randomized controlled trials. A thorough search of Pubmed and other databases was performed. Thirteen trials on 3863 clinically assessed patients were included. Linezolid was slightly more effective than glycopeptides in the intent-to-treat population (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.01–1.10), was more effective in clinically assessed patients (OR 95% CI: 1.38, 1.17–1.64) and in all microbiologically assessed patients (OR 95% CI: 1.38, 1.15–1.65). Linezolid was associated with better treatment in skin and soft-tissue infections (SSTIs) patients (OR 95% CI: 1.61, 1.22–2.12), but not in bacteraemia (OR 95% CI: 1.24, 0.78–1.97) or pneumonia (OR 95% CI: 1.25, 0.97–1.60) patients. No difference of mortality between linezolid and glycopeptides was seen in the pooled trials (OR 95% CI: 0.98, 0.83–1.15). While linezolid was associated with more haematological (OR 95% CI: 2.23, 1.07–4.65) and gastrointestinal events (OR 95% CI: 2.34, 1.53–3.59), a significantly fewer events of skin adverse effects (OR 95% CI: 0.27, 0.16–0.46) and nephrotoxicity (OR 95% CI: 0.45, 0.28–0.72) were recorded in linezolid. Based on the analysis of the pooled data of randomized control trials, linezolid should be a better choice for treatment of patients with S. aureus infections, especially in SSTIs patients than glycopeptides. However, when physicians choose to use linezolid, risk of haematological and gastrointestinal events should be taken into account according to the characteristics of the specific patient populations.

Healthcare Associated Infections of Methicillin-Resistant Staphylococcus aureus: A Case-Control-Control Study

Background Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most widespread and dangerous pathogens in healthcare settings. We carried out this case-control-control study at a tertiary care hospital in Guangzhou, China, to examine the antimicrobial susceptibility patterns, risk factors and clinical outcomes of MRSA infections. Methods A total of 57 MRSA patients, 116 methicillin-susceptible Staphylococcus aureus (MSSA) patients and 102 S. aureus negative patients were included in this study. We applied the disk diffusion method to compare the antimicrobial susceptibilities of 18 antibiotics between MRSA and MSSA isolates. Risk factors of MRSA infections were evaluated using univariate and multivariate logistic regression models. We used Cox proportional hazards models and logistic regression analysis to assess the hospital stay duration and fatality for patients with MRSA infections. Results The MRSA group had significantly higher resistance rates for most drugs tested compared with the MSSA group. Using MSSA patients as controls, the following independent risk factors of MRSA infections were identified: 3 or more prior hospitalizations (OR 2.8, 95% CI 1.3–5.8, P = 0.007), chronic obstructive pulmonary disease (OR 5.9, 95% CI 1.7–20.7, P = 0.006), and use of a respirator (OR 3.6, 95% CI 1.0–12.9, P = 0.046). With the S. aureus negative patients as controls, use of a respirator (OR 3.8, 95% CI 1.0–13.9, P = 0.047) and tracheal intubation (OR 8.2, 95% CI 1.5–45.1, P = 0.016) were significant risk factors for MRSA infections. MRSA patients had a longer hospital stay duration and higher fatality in comparison with those in the two control groups. Conclusions MRSA infections substantially increase hospital stay duration and fatality. Thus, MRSA infections are serious issues in this healthcare setting and should receive more attention from clinicians.

Livestock-associated methicillin and multidrug resistant S. aureus in humans is associated with occupational pig contact, not pet contact.

This study aimed to explore the association of livestock-associated S. aureus with occupational pig contact and pet contact. In this cross-sectional study, 1,422 participants (including 244 pig workers, 200 pet-owning workers and 978 control workers) responded to a questionnaire and provided a nasal swab for S. aureus analysis. Resulting isolates were tested for antibiotic susceptibility, the immune evasion cluster (IEC) genes, and multilocus sequence type. Compared with controls, the pig workers demonstrated a greater prevalence of multidrug-resistant S. aureus (MDRSA) [prevalence ratio (PR) = 3.38; 95% CI: 2.07–5.53] and methicillin-resistant S. aureus (MRSA) (PR = 7.42; 95% CI: 3.71–14.83), but the prevalence of MDRSA and MRSA was similar in pet-owning workers and controls. There was a positive relation of frequency of pig contact with prevalence of MDRSA and MRSA carriage. Only pig workers carried MDRSA CC9 (16 isolates) and MRSA CC9 (16 isolates), and all of these isolates were tetracycline resistant and absent of IEC genes. These findings suggest that livestock-associated MRSA and MDRSA(CC9, IEC-negative, tetracycline-resistant) in humans is associated with occupational pig contact, not pet contact, and support growing concern about antibiotics use in pig farms and raising questions about the potential for occupational exposure to opportunistic S. aureus.

Second-hand smoke exposure in different types of venues: before and after the implementation of smoke-free legislation in Guangzhou, China

Objectives Smoke-free legislation was implemented in Guangzhou on 1 September 2010. However, the smoke-free policy did not cover all indoor areas and smoking rooms can be set in some public places. This study aimed to assess changes in self-reported second-hand smoke (SHS) exposure in different types of venues and in homes, in order to evaluate the effectiveness of smoke-free legislation. Methods/design A repeated cross-sectional survey of representative participants was conducted in Guangzhou before and after the smoke-free legislation. Logistic regression models were used to examine the effectiveness of smoke-free legislation. Main outcome measures Self-reported exposure to SHS,antitobacco advertisements and tobacco advertisements. Participants A total of 4900 participants before the ban and 5135 participants after the ban were selected using a multistage stratified design. Results In full smoking ban places, overall self-reported SHS exposure has declined significantly from 58.8% to 50.3% (p<0.05) with greater drops in cultural venues, government offices and commercial venues. The smoke-free policy did not alter SHS exposure in smokers’ homes (39.6% in 2009 vs 40.0% in 2011; p=0.454). Although a slight decrease in SHS exposure was observed in smoking rooms in hotels, workplaces, restaurants, cafes/bars/nightclubs and amusement parks, SHS continued to be high in those areas. The implementation of smoke-free legislation was accompanied by an increase in antitobacco advertisements. Conclusions SHS exposure declines more significantly in full smoking ban places than in partial smoking ban places. The smoke-free policy in public places does not lead to more SHS exposure in homes. Therefore, it is recommended that Guangzhou should implement a 100% smoke-free policy in all public places and workplaces in the future.

Alarming regional differences in prevalence and antimicrobial susceptibility of group B streptococci in pregnant women: A systematic review and meta-analysis

Group B streptococcus (GBS) is a leading cause of morbidity and mortality in infants. This study aimed to estimate the prevalence, antimicrobial susceptibility and serotype distribution of GBS isolates in pregnant women worldwide. Studies were identified by searching several English and Chinese electronic databases and reviewing relevant articles. Effect estimates were pooled using fixed- or random-effects models. Twenty-eight studies were included in this systematic review. The pooled prevalence of GBS carriage in pregnant women was 10%, being significantly lower in Asia (7%) compared with non-Asian countries (19%). Most of the GBS isolates were susceptible to penicillin, ampicillin and vancomycin. The pooled rates of resistance to erythromycin and clindamycin were 25% and 27%, respectively, and were notably higher in Asia compared with non-Asian countries. The pooled rate of resistance to tetracycline was 73%, with similar high levels in Asia and non-Asian countries. The most prevalent serotypes of GBS isolates were serotypes III, V and Ia. These findings suggest that penicillin is still the first choice for intrapartum prophylaxis of GBS diseases and support growing concern about antibiotic use (especially erythromycin and clindamycin) in Asia.

Variants in the 5′-upstream region of GPC5 confer risk of lung cancer in never smokers

BACKGROUND A recent genome-wide study (GWAS) has identified GPC5 as a promising susceptibility gene for Lung cancer in never smokers (LCINS). However, the most significant single nucleotide polymorphism (SNP) in this GWAS, rs2352028, has yielded controversial results. The aim of this study was to clarify the relationship between rs2352028 and LCINS. Considering that rs2352028 might be largely marker-SNP correlated to causative variants, two predicted functional SNPs, rs3759452 and rs7322083, were additionally investigated in this study. METHODS A hospital based case-control study including 298 cases and 599 controls in a never-smoking Chinese Han population was conducted, and then a meta-analysis combining our data and published data was performed to verify the findings. RESULTS The SNP rs3759452, predicted to potentially change transcription factor binding site of GPC5, was significantly associated with LCINS risk (odds ratio for dominant model=1.55, 95% confidence interval=1.14-2.12). Nevertheless, no significant evidence was showed for rs2352028, both in our case-control study and the meta-analysis including 13 studies of 2342 LCINS cases and 13,398 never-smoking controls. Further subgroup meta-analysis according to population ethnicity and cancer histology also reported no significant association of rs2352028. CONCLUSIONS The association conferring rs3759452 further supports the value of GPC5 in susceptibility to LCINS. Nevertheless, comprehensive analyses are warranted to dissect the functional mechanism underpinning rs3759452.

Dose–response relations between second-hand smoke exposure and depressive symptoms among middle-aged women

A growing body of evidence indicates a strong association between smoking and depression. However, little is known about the possible effects of second-hand smoke (SHS) exposure on depression. This study aimed to examine the potential dose-response relation between SHS exposure and depressive symptoms among non-smoking middle-aged women. A cross-sectional survey was conducted using a stratified three-stage sampling method. Depressive symptoms were measured by the Center for Epidemiologic Studies Depression Scale with a cut-off point of 16. Self-reported SHS exposure was defined as non-smokers׳ inhalation of the smoke exhaled from smokers on at least one day a week. The multivariable logistic regression analysis was completed with adjustment for potential confounders. Among 1280 middle-aged women, 19.4% were classified as having depressive symptoms. There was a 104% increased odds of depressive symptoms corresponding to SHS exposure in general (OR=2.04, 95% CI 1.48-2.79) using no exposure as reference. There were significant positive relations between SHS exposure in general and depressive symptoms in a dose-response manner. These significant trends were observed consistently whether SHS exposure occurred in homes or workplaces. Our findings suggest that long-term and regular SHS exposure is associated with a significant, dose-dependent increase in risk of depressive symptoms.