Nuno Lunet

Differences in prevalence, awareness, treatment and control of hypertension between developing and developed countries.

Objective To systematically review quantitative differences in the prevalence, awareness, treatment and control of hypertension between developed and developing countries over the past 6 years. Methods We searched Medline [prevalence AND awareness AND treatment AND control AND (hypertension OR high blood pressure)] for population-based surveys. Prevalence, awareness, treatment and control of hypertension were compared between men and women, and between developing and developed countries, adjusting for age. The proportions of awareness, treatment and control were defined relative to the total number of hypertensive patients. Results We identified 248 articles, of which 204 did not fulfill inclusion criteria. The remaining articles reported data from 35 countries. Among men, the mean prevalence, awareness, treatment and control of hypertension were 32.2, 40.6, 29.2 and 9.8%, respectively, in developing countries and 40.8, 49.2, 29.1 and 10.8%, respectively, in developed countries. Among women, the mean prevalence, awareness, treatment and control of hypertension were 30.5, 52.7, 40.5, and 16.2%, respectively, in developing countries and 33.0, 61.7, 40.6 and 17.3%, respectively, in developed countries. After adjusting for age, the prevalence of hypertension among men was lower in developing than in developed countries (difference, −6.5%; 95% confidence interval, −11.3 to −1.8%). Conclusion There were no significant differences in mean prevalence, awareness, treatment and control of hypertension between developed and developing countries, except for a higher prevalence among men in developed countries. The prevalence, awareness, treatment and control of hypertension in developing countries are coming closer to those in developed countries.

Worldwide trends in gastric cancer mortality (1980-2011), with predictions to 2015, and incidence by subtype.

Gastric cancer incidence and mortality decreased substantially over the last decades in most countries worldwide, with differences in the trends and distribution of the main topographies across regions. To monitor recent mortality trends (1980-2011) and to compute short-term predictions (2015) of gastric cancer mortality in selected countries worldwide, we analysed mortality data provided by the World Health Organization. We also analysed incidence of cardia and non-cardia cancers using data from Cancer Incidence in Five Continents (2003-2007). The joinpoint regression over the most recent calendar periods gave estimated annual percent changes (EAPC) around -3% for the European Union (EU) and major European countries, as well as in Japan and Korea, and around -2% in North America and major Latin American countries. In the United States of America (USA), EU and other major countries worldwide, the EAPC, however, were lower than in previous years. The predictions for 2015 show that a levelling off of rates is expected in the USA and a few other countries. The relative contribution of cardia and non-cardia gastric cancers to the overall number of cases varies widely, with a generally higher proportion of cardia cancers in countries with lower gastric cancer incidence and mortality rates (e.g. the USA, Canada and Denmark). Despite the favourable mortality trends worldwide, in some countries the declines are becoming less marked. There still is the need to control Helicobacter pylori infection and other risk factors, as well as to improve diagnosis and management, to further reduce the burden of gastric cancer.

Hypertension Prevalence, Awareness, Treatment, and Control in Mozambique: Urban/Rural Gap During Epidemiological Transition

The prediction of cardiovascular risk profile trends in low-income countries and timely action to modulate their transitions are among the greatest global health challenges. In 2005 we evaluated a nationally representative sample of the Mozambican population (n=3323; 25 to 64 years old) following the Stepwise Approach to Chronic Disease Risk Factor Surveillance. Prevalence of hypertension (systolic blood pressure ≥140 mm Hg and/or diastolic blood pressure ≥90 mm Hg and/or antihypertensive drug therapy), awareness (having been informed of the hypertensive status by a health professional in the previous year), treatment among the aware (use of antihypertensive medication in the previous fortnight), and control among those treated (blood pressure <140/90 mm Hg) were 33.1% (women: 31.2%; men: 35.7%), 14.8% (women: 18.4%; men: 10.6%), 51.9% (women: 61.1%; men: 33.3%), and 39.9% (women: 42.9%; men: 28.7%), respectively. Urban/rural comparisons are presented as age- and education-adjusted odds ratios (ORs) and 95% CIs. Among women, hypertension (OR: 2.0; 95% CI: 1.2 to 3.0) and awareness (OR: 4.3; 95% CI: 1.9 to 9.5) were more frequent in urban areas. No urban/rural differences were observed in men (hypertension: OR: 1.3, 95% CI: 0.9 to 2.0; awareness: OR: 1.5, 95% CI: 0.5 to 4.7). Treatment prevalence was not significantly different across urban/rural settings (women: OR: 1.4, 95% CI: 0.5 to 4.4; men: OR: 0.3, 95% CI: 0.1 to 1.4). Control was less frequent in urban women (OR: 0.2; 95% CI: 0.0 to 1.0) and more frequent in urban men (OR: 78.1; 95% CI: 2.2 to 2716.6). Our results illustrate the changing paradigms of “diseases of affluence” and the dynamic character of epidemiological transition. The urban/rural differences across sexes support a trend toward smaller differences, emphasizing the need for strategies to improve prevention, correct diagnosis, and access to effective treatment.

Dietary patterns and colorectal cancer: systematic review and meta-analysis.

Studies on the association between single foods or nutrients and colorectal cancer have provided inconsistent results. Previous reviews did not conduct a quantitative synthesis of the relation with dietary patterns. We conducted a systematic review and meta-analysis of studies addressing the association between dietary patterns and colorectal cancer. Studies quantifying the association between dietary patterns (defined a posteriori) and colorectal cancer were identified in PubMed (until 01.08.2010) and through backward and forward citation tracking (ISI Web of Science and Scopus). Summary relative risk (RR) estimates and 95% confidence intervals (95% CI) were computed for highest versus lowest levels of exposure, for colon cancer (CC) and rectal cancer (RC), and for proximal and distal CC, by random effects meta-analysis. Heterogeneity was quantified using the I2 statistic. Eight cohort and eight case–control studies defining patterns through principal components and factor analyses were included in the systematic review. Meta-analyses were conducted for three patterns: (i) ‘drinker,’ characterized by high alcohol consumption (CC: RRcombined=0.96, 95% CI: 0.82–1.12, I2=0.6%; RC: RRcombined=0.83, 95% CI: 0.47–1.45, I2=65.1%); (ii) ‘healthy,’ characterized by high fruit/vegetables consumption (CC: RRcombined=0.80, 95% CI: 0.70–0.90, I2=55.1%; RC: RRcombined=1.02, 95% CI: 0.89–1.17, I2=10.8%); (iii) ‘western,’ characterized by high red/processed meat consumption (CC: RRcombined=1.29, 95% CI: 1.13–1.48, I2=31.7%; RC: RRcombined=1.13, 95% CI: 0.92–1.39, I2=40.6%). Summary estimates for proximal and distal CC were similar. The risk of CC was increased with patterns characterized by high intake of red and processed meat and decreased with those labelled as ‘healthy.’ No significant associations were observed for RC.

Fruit and Vegetables Consumption and Gastric Cancer: A Systematic Review and Meta-Analysis of Cohort Studies

Abstract: Fruit and vegetable intake is widely recognized as protective for gastric cancer occurrence but prospective research challenged this belief. To evaluate the influence of design options in such results we did a meta-analysis of relevant published cohort studies identified from inception to 2004 in PubMed, EMBASE®, and LILACS. Random-effects meta-analysis, stratification, and meta-regression were used to pool effects and to analyze the association with type of outcome event and length of follow-up independent of other study characteristics. An inverse association was observed between fruit intake and gastric cancer incidence (relative risk, RR = 0.82; 95% confidence interval, CI = 0.73-0.93) and stronger for follow-up periods of ≥10 yr (RR = 0.66; 95% CI = 0.52-0.83) but not when the study outcome was death (RR = 1.08; 95% CI = 0.86-1.35). For vegetables, the RR was 0.88 (95% CI = 0.69-1.13) using all incidence studies and 0.71 (95% CI = 0.53-0.94) when considering only those with the longer follow-up. The association observed between vegetable intake and gastric cancer mortality was 1.05 (95% CI = 0.89-1.25). Other study characteristics assessed added no significant contribution to explain heterogeneity. This meta-analysis showed that design options might play a key role in the observed magnitude or the direction of the association between fruit and vegetable intake and gastric cancer.

Caffeine Exposure and the Risk of Parkinson's Disease: A Systematic Review and Meta-Analysis of Observational Studiess

Several studies conducted worldwide report an inverse association between caffeine/coffee consumption and the risk of developing Parkinsons disease (PD). However, heterogeneity and conflicting results between studies preclude a correct estimation of the strength of this association. We conducted a systematic review and meta-analysis of published epidemiological studies to better estimate the effect of caffeine exposure on the incidence of PD. Data sources searched included Medline, LILACS, Scopus, Web of Science and reference lists, up to September 2009. Cohort, case-control and cross-sectional studies were included. Three independent reviewers selected the studies and extracted the data on to standardized forms. Twenty-six studies were included: 7 cohort, 2 nested case-control, 16 case-control, and 1 cross-sectional study. Quantitative data synthesis of the most precise estimates from each study was accomplished through random effects meta-analysis. Heterogeneity was quantified using the I2 statistic. The summary RR for the association between caffeine intake and PD was 0.75 [[95% Confidence Interval (95%CI): 0.68-0.82], with low to moderate heterogeneity (I2= 28.8%). Publication bias for case-control/cross-sectional studies may exist (Eggers test, p=0.053). When considering only the cohort studies, the RR was 0.80 (95%CI: 0.71-90; I2=8.1%). The negative association was weaker when only women were considered (RR=0.86, 95%CI: 0.73-1.02; I2=12.9%). A linear relation was observed between levels of exposure to caffeine and the RR estimates: RR of 0.76 (95%CI: 0.72-0.80; I2= 35.1%) per 300 mg increase in caffeine intake. This study confirm an inverse association between caffeine intake and the risk of PD, which can hardly by explained by bias or uncontrolled confounding.

Erratum to: Prevalence of Helicobacter pylori Infection Worldwide: A Systematic Review of Studies with National Coverage

The systematic assessment of large population-based surveys addressing the prevalence of Helicobacter pylori infection may provide robust evidence for understanding the trends in the exposure to this major risk factor across settings with distinct patterns of gastric cancer variation. Our aim was to describe the prevalence of H. pylori infection in different countries and periods, through systematic review of the literature. We searched PubMed from inception up to September 2013 to identify original studies reporting on the prevalence of H. pylori, and only those evaluating samples with national coverage were included. We identified 37 eligible studies including data for 22 countries. The prevalences were higher in Central/South America and Asia, and at least two-fold higher in countries with high gastric cancer incidence. In most countries presenting data for different time periods, the prevalences were usually lower in the most recent surveys. However, there was little variation in settings where prevalences were already low. Among countries with high prevalence of H. pylori infection there is an ample scope for reducing its burden in the next decades, whereas further declines in settings with already low prevalences will require more intensive efforts.

Caffeine Intake and Dementia: Systematic Review and Meta-Analysis

A recent meta-analysis of 4 studies published up to January 2004 suggests a negative association between coffee consumption and Alzheimers disease, despite important heterogeneity in methods and results. Several epidemiological studies on this issue have been published since then, warranting an update of the insights on this topic. We conducted a systematic review and meta-analysis of published studies quantifying the relation between caffeine intake and cognitive decline or dementia. Data sources searched included Medline, LILACS, Scopus, Web of Science and reference lists, up to September 2009. Cohort and case-control studies were included. Three independent reviewers selected the studies and extracted the data on to standardized forms. Nine cohort and two case-control studies were included. Quantitative data synthesis of the most precise estimates from each study was accomplished through random effects meta-analysis. Heterogeneity was quantified using the I2 statistic. The outcomes of the studies considered for meta-analysis were Alzheimers disease in four studies, dementia or cognitive impairment in two studies, and cognitive decline in three studies. The summary relative risk (RR) for the association between caffeine intake and different measures of cognitive impairment/decline was 0.84 [95% Confidence Interval (95% CI): 0.72-0.99; I2=42.6%]. When considering only the cohort studies, the summary RR was 0.93 (95% CI: 0.83-1.04, I2= 0.0%), and 0.77 (95% CI: 0.63-0.95, I2= 34.7%), if the most influential study was excluded. This systematic review and meta-analysis found a trend towards a protective effect of caffeine, but the large methodological heterogeneity across a still limited number of epidemiological studies precludes robust and definite statements on this topic. and definite statements on this topic.

Expression of FOXA1 and GATA-3 in breast cancer: the prognostic significance in hormone receptor-negative tumours

IntroductionThe expression of additional genes, other than oestrogen receptor (ER), may be important to the hormone-responsive phenotype of breast cancer. Microarray analyses have revealed that forkhead box A1 (FOXA1) and GATA binding protein 3 (GATA-3) are expressed in close association with ERα, both encoding for transcription factors with a potential involvement in the ERα-mediated action in breast cancer. The purpose of this study was to explore if the expression of FOXA1 and GATA-3 may provide an opportunity to stratify subsets of patients that could have better outcome, among the ERα-negative/poor prognosis breast cancer group.MethodsWe evaluate FOXA1 and GATA-3 expression in 249 breast carcinomas by immunohistochemistry, associating it with breast cancer molecular markers, clinicopathological features and patients survival. The clinicopathological features and immunohistochemical markers of the tumours were compared using the chi-square test and ANOVA. Disease-free survival was analysed through Kaplan–Meier survival curves and Cox regression.ResultsFOXA1 expression was demonstrated in 42% of invasive carcinomas, while GATA-3 was detected in 48% of the cases. FOXA1 expression was inversely associated with tumour size, Nottingham Prognostic Index, histological grade, lymph vascular invasion, lymph node stage and human epidermal growth factor receptor-2 (HER-2) overexpression, while GATA-3 expression showed inverse association with histological grade and HER-2. Both FOXA1 and GATA-3 were directly associated with ERα and progesterone receptor. Among FOXA1-positive tumours, 83.1% are comprised in the luminal A subtype, similar to GATA-3 where 87.7% of positive tumours were classified within this molecular subtype. In the subset of ERα-negative patients, those who were FOXA1-negative had a 3.61-fold increased risk of breast cancer recurrence when compared with the FOXA1-positive.ConclusionsFOXA1 was a significant predictor of good outcome in breast cancer, whereas GATA-3 was an important luminal marker. The expression of FOXA1 may be used for risk stratification among ERα-negative patients.

Helicobacter pylori infection and gastric cancer: Facing the enigmas

At an individual level Helicobacter pylori was associated with the occurrence of gastric cancer but in some African and Asian countries its prevalence runs with low gastric cancer rates, the so‐called African and Asian enigmas. We assessed whether the association between gastric cancer and H. pylori prevalence at an area level is modified by the level of exposure to fruits and vegetables, alcohol or tobacco. Regression models were fitted to data from 58 countries using as dependent variable log transformed gastric cancer rates and as independent covariables the H. pylori prevalence, fruits and vegetables consumption, cigarette smoking, alcohol intake and interaction terms. The levels of alcohol consumption or cigarette smoking modified the association between gastric cancer and H. pylori infection. Models including H. pylori prevalence, alcohol consumption, cigarette smoking and the interaction terms H. pylori × alcohol or H. pylori × tobacco were used to compute gastric cancer incidence multiplying regression coefficients by a H. pylori prevalence of 85% (the approximate median in African countries) and the median figures observed in each continent for alcohol and tobacco availability. The expected gastric cancer incidence per 100,000 would be 5.7 assuming the alcohol and tobacco availability in African countries, 7.0 in Asia and Oceania, 16.0 in America and 26.0 in Europe. The interaction between H. pylori and cigarette or alcohol consumption may contribute to further explain the international variation in gastric cancer and the so‐called African and Asian enigmas.