Factors for the Primary Prevention of Breast Cancer: A Meta-Analysis of Prospective Cohort Studies.

BACKGROUND: This report provided the effect of 15 preventable factors on the risk of breast cancer incidence. STUDY DESIGN: A systematic review and meta-analysis. METHODS: A detailed research was conducted on PubMed, Web of Science, and Scopus databases in January 2020. Reference lists were also screened. Prospective cohort studies addressing the associations between breast cancer and 15 factors were analyzed. Between-study heterogeneity was investigated using the χ2, τ2, and I2 statistics. The probability of publication bias was explored using the Begg and Egger tests and trim-and-fill analysis. Effect sizes were expressed as risk ratios (RRs) with 95% confidence intervals (CIs) using a random-effects model. RESULTS: Based on the results, out of 147,083 identified studies, 197 were eligible, including 19,413,702 participants. The RRs (95% CI) of factors associated with breast cancer were as follows: cigarette smoking 1.07 (1.05, 1.09); alcohol drinking 1.10 (1.07, 1.12); sufficient physical activity 0.90 (0.86, 0.95); overweight/obesity in premenopausal 0.92 (0.82, 1.03) and postmenopausal 1.18 (1.13, 1.24); nulliparity 1.16 (1.03, 1.31); late pregnancy 1.37 (1.25, 1.50); breastfeeding 0.87 (0.81, 0.93); ever using oral contraceptive 1.00 (0.96, 1.05); ever using estrogen 1.13 (1.04, 1.23); ever using progesterone 1.02 (0.84, 1.24); ever using estrogen/progesterone 1.60 (1.42, 1.80); ever taking hormone replacement therapy 1.26 (1.20, 1.32); red meat consumption 1.05 (1.00, 1.11); fruit/vegetable consumption 0.87 (0.83, 0.90); and history of radiation therapy, based on single study 1.31 (0.87, 1.98). CONCLUSION: This meta-analysis provided a clear picture of several factors associated with the development of breast cancer. Moreover, the useful information in this study may be utilized for ranking and prioritizing preventable risk factors to implement effective prevention programs.

Geographical distribution of at fault drivers involved in fatal traffic collisions in Tehran, Iran.

OBJECTIVES: According to Traffic Police, about 35% of deaths and more than 50% of injuries caused by traffic collision in the roads of Tehran are among drivers and car occupants. This study was conducted to determine areas with the highest number of traffic collisions and perform spatial analysis of traffic collisions involving drivers in Tehran during April 2014 to March 2017. METHODS: The present study was a cross-sectional and descriptive-analytic research. In this study, all traffic collision that driver was accounted (100 percent or less) for crash occurrence which resulted in the death of at least one person (driver, pedestrian or passenger) were included in the analyses. Geographic information system software was used to show spatial distribution of events from zoning maps. Moran index was used in the mathematical analysis in order to determine the distribution pattern of the events from and Getis-Ord G statistics was applied to analyze the hot spots (high risk points). RESULTS: A total number of 519 traffic collisions were investigated in this study. Moreover, 283 cases (54.5%) of the incidents took place in direct routes and 236 cases (45.5%) occurred at intersections. The most frequent events were in the region 4 (57 cases) and the least frequent events were reported in the region 10 (6 cases). Moran statistics show that the distribution of the studied events significantly follows the cluster pattern (p<0.001). CONCLUSIONS: The northeastern and northwest margins of Tehran are the most prone areas for drivers involved with traffic collisions leading to death. Most traffic collisions leading to death take place at highways located at the entrance and exit points of Tehran and highways in regions 2 and 5.

Adverse events following immunization with pentavalent vaccine: experiences of newly introduced vaccine in Iran.

BACKGROUND: The most important factors that affect the incidence of vaccine-related complications are the constituent biological components of the vaccine, injection site reactions, age and sex. The aim of this study is to determine the incidence rate of adverse events following immunization with pentavalent vaccine (DTPw-Hep B-Hib (PRP-T) vaccine (pentavac) (adsorbed) is manufactured by Serum Institute of India ltd), which was introduced in Iran in November 2014. It is important to monitor vaccine-related adverse events because of the role of vaccine safety in immunization program success. METHODS: This study was a mixed cohort study that included 1119 children less than 1 year of age. In 2015, the children were referred to Hamadan health centers to receive pentavalent vaccine at 2, 4 and 6 months of age. The data were collected from the parents of the children using a questionnaire that was administered either face-to-face or by telephone. The cumulative incidence of side effects and risk ratio was reported with 95% confidence intervals (CI). Chi-squared tests and logistic regressions were used to investigate the association between the variables. RESULTS: The cumulative incidence rate of pentavalent-related adverse events during 48 h following immunization was estimated to be 15.8% for swelling, 10.9% for redness, 44.2% for pain, 12.6% for mild fever, 0.1% for high fever, 20.0% for drowsiness, 15.0% for loss of appetite, 32.9% for irritability, 4.6% for vomiting and 5.5% for persistent crying. There is no evidence for the occurrence of convulsion and encephalopathy among children who receive pentavalent vaccines. CONCLUSION: Further large studies with long time follow up are required to address rare events include convulsions, encephalopathy or persistent crying. However, Findings urge immunization programs to use pentavalent vaccinations and to continue implementing the current immunization program in children under 1 year of age.

Effect of Consanguinity on Low Birth Weight: A Meta-Analysis.

BACKGROUND: Consanguinity (when couples share at least one common ancestor) is a public health issue with a variety of distributions and incidence rates worldwide. Several epidemiological studies have explored the association between consanguinity and low birth weight (LBW). However, the results are inconsistent. This meta-analysis aimed to explore the overall association between consanguineous marriage and LBW. METHODS: We searched PubMed, Web of Science, Scopus, ScienceDirect, and reference lists of articles up to May 2015. We included cohort, case-control, and cross-sectional studies addressing the association between consanguinity and LBW. We assessed heterogeneity using Q-test and I2 statistic. We explored publication bias using the Egger's and Begg's tests and the funnel plot. We meta-analyzed the data and reported the overall odds ratio (OR) and mean difference with 95% confidence intervals (CI) using the random-effects model. RESULTS: We included 24 out of 3941 retrieved studies, with 44,131 participants. We indicated that LBW was associated significantly with first-cousin marriages (OR = 1.36; 95% CI: 1.03, 1.69) and non-significantly with second-cousin marriages (OR = 1.20; 95% CI: 0.49, 1.91). Furthermore, first-cousin marriages can reduce the birth weight of siblings of consanguineous couples 144 g more compared to non-consanguineous marriages. CONCLUSIONS: This meta-analysis measured the association between consanguinity and LBW. Based on the current evidence, consanguineous marriage can increase the risk for LBW. However, further evidence based on large cohort studies conducted in different settings is required to make a robust conclusion regarding the effect of consanguinity on LBW.

How much excess weight loss can reduce the risk of hypertension?

Background: A 25% relative reduction in the prevalence of hypertension is a global target. This meta-analysis estimated the effect of excess weight loss on hypertension. Methods: We searched PubMed, Web of Science and Scopus until January 2016. We included prospective cohort studies addressing the association between overweight/obesity and hypertension. We expressed the strength of association using risk ratio and the excess risk using attributable risk fraction with 95% CI based on the random-effects model. Results: We found 7617 references and included 10 studies with 173 828 participants. Compared with normal weight, the risk ratio of hypertension was 1.52 (1.37, 1.67; 9 studies, I2 = 82.4%) for overweight and 2.17 (1.84, 2.50; 9 studies, I2 = 88.9%) for obesity. The excess risk of hypertension attributable to overweight was 32% (24%, 40%; 8 studies, I2 = 85.5%) and that attributable to obesity was 47% (40%, 54%; 8 studies, I2 = 88.2%). That means, excess weight loss may reduce the risk of hypertension by between 24% and 40% in people who are overweight and by between 40% and 54% in people who are obese. Conclusions: Excess weight loss is a vital strategy for controlling hypertension and is sufficient for achieving the global target, particularly if it is accompanied with other preventive measures.

Prevalence of Nasopharyngeal Carriage of Streptococcus pneumonia in Iran: A Meta-Analysis.

BACKGROUND: Streptococcus pneumoniae is a major cause of childhood morbidity and mortality worldwide. Several studies have explored the nasopharyngeal carriage of S. pneumonia in Iran. This meta-analysis is aimed at exploring the overall prevalence of nasopharyngeal carriage of S. pneumoniae among healthy children and its resistance to antibiotics. METHODS: We have systematically reviewed published studies from international databases (PubMed, Web of Science, and Scopus) and national databases (Iranmedex, Magiran, Medlib, SID and Irandoc) and reference lists of articles published up to May 2015. Only cross-sectional studies supported with sensitivity test on samples collected from nasopharyngeal area were included and heterogeneity was assessed using Q-test and I2 test statistic. Publication bias was explored using the Egger's and Begg's tests and the funnel plot. The overall prevalence of analyzed data were reported with 95% confidence intervals (CI) using the random-effects model. RESULTS: A total of 16 studies were included in the final analysis. The pooled prevalence of S. pneumoniae nasopharyngeal carriage was 18% (95% CI: 14% - 23%). Antibiotic resistance rates were 26% (95% CI: 15% - 37%) to penicillin, 30% (95% CI: 10% - 49%) to erythromycin and 34% (95% CI: 10% - 57%) to tetracycline respectively. CONCLUSION: This study could be able effectively estimate the overall prevalence of nasopharyngeal carriage of S. pneumoniae and its antibiotics resistance rate among healthy children in Iran. In addition, the findings evidenced the role of pneumococcal vaccination in reducing the prevalence of S. pneumoniae carriage among healthy children in Iran.