Ariel Bardach

Association between cigarette smoking prevalence and income level: a systematic review and meta-analysis.

Introduction Previous evidence linked low socioeconomic status with higher smoking prevalence. Our objective was to assess the strength of this association in the world population, updating a previous work. Methods Systematic review and meta-analysis of observational studies. Subgroup analyses included continents, WHO regions, country mortality levels, gender, age, risk of bias, and study publication date. Independent reviewers selected studies, assessed potential bias and extracted data. We searched MEDLINE, EMBASE, CENTRAL, SOCINDEX, AFRICAN INDEX MEDICUS, and LILACS, and other sources from 1989 to 2013 reporting direct measurements of income and current cigarette smoking. Results We retrieved 13,583 articles and included 93 for meta-analysis. Median smoking prevalence was 17.8% (range 3-70%). Lower income was consistently associated with higher smoking prevalence (odds ratio [OR]: 1.45; 95% confidence interval [CI]: 1.35-1.56). This association was statistically significant in the subgroup analysis by WHO regions for the Americas (OR: 1.54; 95% CI: 1.42-1.68), South East Asia (OR: 1.53; 95% CI: 1.10-2.00), Europe (OR: 1.45; 95% CI: 1.29-1.63), and Western Pacific (OR: 1.32; 95% CI: 1.02-1.72), and in studies conducted during 1990s (OR: 1.42; 95% CI: 1.24-1.62) and 2000s (OR: 1.48; 95%CI: 1.30-1.64). Likewise, it was noted in low-mortality countries (OR: 1.48; 95% CI: 1.37-1.60) and for both genders. Prevalence was highest in the lowest income levels compared to the middle (OR: 1.69; 95% CI: 1.49-1.92), followed by the middle level compared to the highest (OR: 1.31; 95% CI: 1.20-1.43). Conclusions Our results show that current cigarette smoking was significantly associated with lower income worldwide and across subgroups, suggesting a dose-response relationship. Implications This unique updated systematic review shows a consistent inverse dose-response relationship between cigarette smoking and income level, present among most geographical areas and country characteristics. Public health measures should take into account this potential inequity and consider special efforts directed to disadvantaged populations.

Prognosis of metastatic giant cell tumor of bone in the pre-denosumab era. A systematic review and a meta-analysis

Background Data on long-term prognosis of metastatic GCT (mGCT) is scant. The frequency of spontaneous regressions (SRs) is unknown. We aimed to estimate the prognosis of mGCT. Methods We searched electronic scientific literature databases and generic Internet from January 1980 to August 2017. After identifying eligible studies we performed descriptive analyses and meta-analyses to estimate overall survival (OS), disease specific survival (DSS) and frequency of SRs in the years before the widespread use of denosumab. We performed pre-specified subgroup analyses of studies published before and after 2000 and of those with more and less than 10 years of follow-up. Results After retrieving and combining data from 26 relevant retrospective case-series totaling 242 patients with a median follow-up of 6.9 years, the estimated pooled OS was 86.9% (95% CI 78.0-94.2). Pooled DSS was 88.0% (95% CI 79.7-94.7). SRs were observed in 4.5% of patients. In the subgroup of studies published after 2000 mGCT was the only cause of death of affected subjects. In case-series with a follow-up longer than 10 years pooled DSS was 69.7% (95% CI 25.5-99.8). Conclusions To our knowledge this is the first study to derive estimated pooled OS and DSS of mGCT based on a large dataset. SRs were not exceptional phenomena. In a long run the disease could impact in a significant way on the life expectancy of affected subjects.