The Association of PTEN Gene Mutations with the Breast Cancer Risk: A Systematic Review and Meta-analysis.

Breast cancer (BC) is the most common malignancy in women in western countries. A significant part of malignant cases is caused by genetic mutation. Mutations in the gene phosphatase and tensin homologue deleted on chromosome (PTEN) have been proven in various malignancies. The present study was conducted with the aim of investigating the prevalence of BC due to PTEN gene mutation, as well as estimating the chance of developing BC due to the occurrence of PTEN gene mutation. The present study was conducted using a systematic review method based on PRISMA 2020 statements. The search was done in PubMed, Web of Science (WOS), Scopus, and direct scientific databases. The search was performed using the keywords breast cancer, breast malignancy, PTEN, polymorphism, mutation, variant, and their equivalents. Statistical analysis was performed using the second version of Comprehensive Meta-Analysis Software. A total of 2138 articles were collected. After removing duplicate articles, checking the title and abstract, and then checking the full text of the documents, finally 64 articles were approved and entered the systematic review process. Analysis of these studies with a sample size of 231,179 showed the prevalence of breast cancer patients with PTEN mutations. The combined results of 64 studies showed that the prevalence of PTEN mutations has a 3.3 (95% CI 2.2-5) in BC patients, and an analysis of 6 studies showed that the odds ratio of developing BC due to PTEN mutation is 3.7 (95% CI 1.1-11.9). The results of this study show that mutation in the PTEN gene increases the chance of developing BC. However, it was found that a small part of patients gets BC due to the occurrence of mutation in this gene.

Global prevalence of constipation in older adults: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: Constipation is one of the most common functional disorders of the gastrointestinal tract in older adults. To date, no systematic review or previous meta-analysis has estimated the global prevalence of constipation in older adults. The prevalence of this disorder has been reported differently in different studies; therefore, this study aims to systematically review the publications and to perform a meta-analysis of the prevalence of constipation in older adults. METHODS: The electronic databases PubMed, Google Scholar, Scopus, Web of Science, and ScienceDirect were systematically searched for studies reporting the prevalence of constipation in older adults up to February 2022. To perform the analysis, the random effects model was used, and heterogeneity was assessed by Cochran's Q test and expressed as I2. RESULTS: Out of 5341 evaluated publications, 36 met the eligibility criteria. These studies included 58,405 older adults aged 60-93 years. The overall prevalence of constipation in older adults was 18.9% (95% confidence interval [95% CI]: 14.7-23.9%). The prevalence of constipation in older adults according to Rome II criteria was 16.2% (95% CI: 6.8-33.7), based on Rome III criteria was 19.2% (95% CI: 12.6-28.1), and based on Rome IV criteria was 10.3% (95% CI: 5.8-17.7). The highest prevalence of constipation was found in older adults in Africa at 32.3% (95% CI: 21.5-45.4), and the lowest in Asia at 13.6% (95% CI: 9.1-19.9). Concerning diagnostic tools, the highest prevalence of constipation was found if a self-reporting tool was applied with a value of 19.7% (95% CI: 15.8-24.3). CONCLUSION: The results suggest that health policymakers should pay more attention to the prevention of constipation in older adults, including raising public awareness to the importance of nutrition and diet and physical activity in older adults.

Global prevalence of hepatitis C in general population: A systematic review and meta-analysis.

BACKGROUND: According to published reports from the World Health Organization, it is estimated that more than 3% of the world's population is infected with HCV. Given the impact of various factors on the prevalence of HCV in the world's population and the lack of general statistics around the world, this study aims to review the studies conducted in this field and statistical analysis of the results of general statistical studies on the prevalence of HCV in the world population. METHODS: In this study, systematic review and meta-analysis of information of the studies related to the prevalence of HCV in the world using keywords including: Prevalence, HCV, Hepatitis C, Healthy Population, Healthy subjects, and General Population in SID, MagIran, IranMedex, IranDoc, ScienceDirect, Embase, Scopus, PubMed, Web of Science (WoS) databases and Google Scholar search engine were extracted without time limit until April 2020. In order to perform the analysis of qualified studies, the model of random effects was used, and the inconsistency of studies with I2 index was investigated. Data analysis was performed with Comprehensive Meta-Analysis (Version 2). RESULTS: In a study of 98 studies with a total sample size of 236,964 people in the world, the overall prevalence of HCV was 1.8% (95% CI: 1.4%-2.3%). Also, according to the subgroup analysis in different continents; the highest prevalence of HCV in the African continent was 7.1% (95% CI: 4.4-11.5%). CONCLUSION: The results of this study show that the prevalence of hepatitis C in the world's population, especially in Africa, is almost high. Therefore, the officials of the World Health Organization should design measures to prevent the spread of this infection.