Cadmium exposure and risk of breast cancer: A meta-analysis.

BACKGROUND: Cadmium is a heavy metal with carcinogenic properties, highly prevalent in industrialized areas worldwide. Prior reviews evaluating whether cadmium influences breast cancer have been inconclusive and not reflected several recent studies. OBJECTIVE: To evaluate the association between cadmium exposure and female breast cancer incidence, with an emphasis on separately estimating dietary vs. airborne vs. biomarker measures of cadmium and studies published until October 2022. METHODS: We evaluated risk of bias using set criteria and excluded one study judged to have high risk based on self-report of breast cancer and insufficient adjustment. We conducted a random effects meta-analysis of epidemiological studies, including subgroups by exposure route and by menopausal status. RESULTS: A total of 17 studies were eligible for our meta-analysis. Only 2 studies addressed airborne cadmium directly. Breast cancer risk was elevated in women exposed to higher levels of cadmium across all studies - pooled odds ratio: 1.13 (95% confidence interval: 1.00, 1.28), with notable heterogeneity between studies (I2 = 77%). When examining separately by exposure route, dietary cadmium was not linked with an elevated risk - (OR: 1.05; 95%CI: 0.91, 1.21; I2 = 69%), consistent with prior reviews, but biomarker-based studies showed an elevated but non-significant pooled measure (OR: 1.37; 95%CI: 0.96, 1.94; I2 = 84%). We did not observe any clear patterns of different risk by menopausal status. CONCLUSION: Findings from our meta-analysis suggest that exposure to higher cadmium increases the risk of breast cancer in women, but with remaining questions about whether non-dietary exposure may be more risky or whether residual confounding by constituents of tobacco smoke may be at play.

The relationship between chronic stress, hair cortisol and hypertension.

Inconsistencies in studies of chronic psychosocial stress and hypertension may be explained by the use of stress markers greatly influenced by circadian rhythm and transient stressors. We assessed whether hair cortisol, a marker that captures systemic cortisol over months, was independently associated with hypertension. We measured hair cortisol and blood pressure in 75 consecutive participants in the Survey of the Health of Wisconsin, using an ELISA test. Individuals with values â€‹≥ â€‹median (78.1 â€‹pg/mg) were considered exposed. We used approximate Bayesian logistic regression, with a prior odds ratio of 1.0-4.0, to quantify the multivariate-adjusted hair cortisol-hypertension association. Participants' average age was 46.9 years; 37.3% were male; and 25.3% were hypertensive. Hypertension prevalence was 2.23 times higher in exposed (95% CI: 1.69-3.03). This finding was unlikely explained by differential measurement errors, since we conducted blinded measurements of exposure and outcome. Sensitivity analyses showed the association was unlikely explained by an unmeasured confounder, survival bias, or reverse causality bias. Findings suggest elevated hair cortisol is a risk factor for hypertension. Although feasible, the clinical value of hair cortisol as a tool for hypertension risk stratification or for monitoring the effect of chronic psychosocial stress management interventions is still uncertain.

Factors associated with false-positive self-reported adherence to antihypertensive drugs.

Self-reported medication adherence is known to overestimate true adherence. However, little is known about patient factors that may contribute to the upward bias in self-reported medication adherence. The objective of this study is to examine whether demographic, behavioral, medication and mood factors are associated with being a false-positive self-reported adherer (FPA) to antihypertensive drug treatment. We studied 175 patients (mean age: 50 years; 57% men) from primary-care clinics starting antihypertensive drug treatment. Self-reported adherence (SRA) was measured with the Medication Adherence Report Scale (MARS) and by the number of drug doses missed in the previous week/month, and compared with pill count adherence ratio (PCAR) as gold standard. Data on adherence, demographic, behavioral, medication and mood factors were collected at baseline and every 3 months up to 1 year. FPA was defined as being a non-adherer by PCAR and an adherer by self-report. Mixed effect logistic regression was used for the analysis. Twenty percent of participants were FPA. Anxiety increased (odds ratio (OR): 3.00; P=0.01), whereas smoking (OR: 0.40; P=0.03) and drug side effects (OR: 0.46, P=0.03) decreased the probability for FPA by MARS. Education below high-school completion increased the probability of being an FPA as measured by missing doses in the last month (OR: 1.66; P=0.04) and last week (OR: 1.88; P=0.02). The validity of SRA varies significantly according to drug side effects, behavioral factors and patient's mood. Careful consideration should be given to the use of self-reported measures of adherence among patients likely to be false-positive adherers.

Patterns and predictors of personal exposure to indoor air pollution from biomass combustion among women and children in rural China.

UNLABELLED: Indoor air pollution (IAP) from domestic biomass combustion is an important health risk factor, yet direct measurements of personal IAP exposure are scarce. We measured 24-h integrated gravimetric exposure to particles < 2.5 µm in aerodynamic diameter (particulate matter, PM2.5) in 280 adult women and 240 children in rural Yunnan, China. We also measured indoor PM2.5 concentrations in a random sample of 44 kitchens. The geometric mean winter PM2.5 exposure among adult women was twice that of summer exposure [117 µg/m³ (95% CI: 107, 128) vs. 55 µg/m³ (95% CI: 49, 62)]. Children's geometric mean exposure in summer was 53 µg/m³ (95% CI: 46, 61). Indoor PM2.5 concentrations were moderately correlated with women's personal exposure (r=0.58), but not for children. Ventilation during cooking, cookstove maintenance, and kitchen structure were significant predictors of personal PM2.5 exposure among women primarily cooking with biomass. These findings can be used to develop exposure assessment models for future epidemiologic research and inform interventions and policies aimed at reducing IAP exposure. PRACTICAL IMPLICATIONS: Our results suggest that reducing overall PM pollution exposure in this population may be best achieved by reducing winter exposure. Behavioral interventions such as increasing ventilation during cooking or encouraging stove cleaning and maintenance may help achieve these reductions.

The Latin American Consortium of Studies in Obesity (LASO).

Current, high-quality data are needed to evaluate the health impact of the epidemic of obesity in Latin America. The Latin American Consortium of Studies of Obesity (LASO) has been established, with the objectives of (i) Accurately estimating the prevalence of obesity and its distribution by sociodemographic characteristics; (ii) Identifying ethnic, socioeconomic and behavioural determinants of obesity; (iii) Estimating the association between various anthropometric indicators or obesity and major cardiovascular risk factors and (iv) Quantifying the validity of standard definitions of the various indexes of obesity in Latin American population. To achieve these objectives, LASO makes use of individual data from existing studies. To date, the LASO consortium includes data from 11 studies from eight countries (Argentina, Chile, Colombia, Costa Rica, Dominican Republic, Peru, Puerto Rico and Venezuela), including a total of 32,462 subjects. This article describes the overall organization of LASO, the individual studies involved and the overall strategy for data analysis. LASO will foster the development of collaborative obesity research among Latin American investigators. More important, results from LASO will be instrumental to inform health policies aiming to curtail the epidemic of obesity in the region.

Interethnic differences in the accuracy of anthropometric indicators of obesity in screening for high risk of coronary heart disease.

BACKGROUND: Cut points for defining obesity have been derived from mortality data among Whites from Europe and the United States and their accuracy to screen for high risk of coronary heart disease (CHD) in other ethnic groups has been questioned. OBJECTIVE: To compare the accuracy and to define ethnic and gender-specific optimal cut points for body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) when they are used in screening for high risk of CHD in the Latin-American and the US populations. METHODS: We estimated the accuracy and optimal cut points for BMI, WC and WHR to screen for CHD risk in Latin Americans (n=18 976), non-Hispanic Whites (Whites; n=8956), non-Hispanic Blacks (Blacks; n=5205) and Hispanics (n=5803). High risk of CHD was defined as a 10-year risk > or =20% (Framingham equation). The area under the receiver operator characteristic curve (AUC) and the misclassification-cost term were used to assess accuracy and to identify optimal cut points. RESULTS: WHR had the highest AUC in all ethnic groups (from 0.75 to 0.82) and BMI had the lowest (from 0.50 to 0.59). Optimal cut point for BMI was similar across ethnic/gender groups (27 kg/m(2)). In women, cut points for WC (94 cm) and WHR (0.91) were consistent by ethnicity. In men, cut points for WC and WHR varied significantly with ethnicity: from 91 cm in Latin Americans to 102 cm in Whites, and from 0.94 in Latin Americans to 0.99 in Hispanics, respectively. CONCLUSION: WHR is the most accurate anthropometric indicator to screen for high risk of CHD, whereas BMI is almost uninformative. The same BMI cut point should be used in all men and women. Unique cut points for WC and WHR should be used in all women, but ethnic-specific cut points seem warranted among men.

Independent association between inflammatory markers (C-reactive protein, interleukin-6, and TNF-alpha) and essential hypertension.

High blood pressure (HBP) has been associated with elevated C-reactive protein (CRP), a marker of chronic mild inflammation. However, the association between HBP and other inflammatory markers, particularly interleukin 6 (IL-6) and tumour necrosis alpha (TNF-alpha), has not been evaluated in well-controlled studies. We examined the cross-sectional relationship between IL-6, TNF-alpha, and CRP and HBP in a random sample of 196 healthy subjects. All markers were measured in duplicate with high-sensitivity ELISA tests. Three blood pressure (BP) measurments were averaged for the analysis, and subjects with systolic BP >or=140 and/or diastolic BP >or=90 mmHg were considered hypertensive. Log binomial regression was used to estimate multivariate-adjusted prevalence ratios (PR) of HBP. Of the subjects, 40% (79) were hypertensive (mean age: 44 years; range 30-64). After adjustment for age, sex, body mass index, family history of HBP, and the level of the other inflammatory markers, subjects in the second (PR: 3.10, P=0.003), third (PR: 2.32; P=0.031), and fourth quartiles (PR: 2.30; P=0.036) of IL-6 were more than twice as likely to be hypertensive than those in the first quartile. Corresponding PR estimates for TNF-alpha levels were 1.41 (P=0.014) for the second; 1.59 (P=0.001) for the third; and 1.61 (P=0.025) for the fourth quartile. The CRP-HBP association was not statistically significant. Our results suggest that TNF-alpha and IL-6 could be independent risk factors for HBP in apparently healthy subjects. Nevertheless, the temporal relationship between elevated inflammation markers and HBP should be ascertained in prospective cohort studies.

Inflammation, endothelial dysfunction, and the risk of high blood pressure: epidemiologic and biological evidence.

In spite of its high impact on cardiovascular and renal disease, knowledge on risk factors for the development of high blood pressure (HBP) is limited. Mild chronic inflammation may play a significant role in the incidence of HBP. A persistent low-grade inflammation state could be associated with high but within the 'normal range' cytokine plasma concentration. By impairing the capacity of the endothelium to generate vasodilating factors, particularly nitric oxide (NO), elevated cytokines may lead to the development of endothelial dysfunction, chronic impaired vasodilation, and HBP. These alterations in the L-arginine : NO pathway may play a major role in the development of HBP in young subjects, with inflammation-related alterations in the production of cyclo-oxygenase-derived vasoconstrictors becoming more prominent with advanced age. Cross-sectional independent associations between HBP and plasma levels of C-reactive protein, interleukin-6, and tissue necrosis factor alpha have been reported, but no prospective evidence of these associations is currently available.

[Neuroepidemiology in the eastern region of Colombia]. / Neuroepidemiologia en el Oriente colombiano.

OBJECTIVE: To determine the presence of eight neurological disorders (migraine, cerebrovascular disease, disorders of movement, peripheral neuropathy, mental retardation, epilepsy, dementia and the sequelas of head injuries) in the eastern region of Colombia. PATIENTS AND METHODS: Using the neuro epidemiological protocol of the World Health Organization (WHO), modified by our group, together with a questionnaire to determine the sequelas of head injuries and the abbreviated mental test (Mini mental), we interviewed people in the municipalities of Bucaramanga, Piedecuesta and Aratoca. The persons suspected of having neurological disorders, who were over 12 years old, were evaluated by neurologists and those under 12 years old by a neuropaediatrician. RESULTS: In the eastern region, 1,454 persons altogether were interviewed. Neurological conditions were suspected in 454 of these (31.2%), and confirmed in 437 (30.1%). The specific results for these neurological disorders and their respective confidence intervals (in brackets) were: migraine 198.8 (178.7 220.4); peripheral neuropathy: 26.8 (19.4 36.9); epilepsy: 22.7 (15.9 32.1); dementia: 17.9 (11.9 26.5); cerebrovascular disease: 17.2 (11.4 25.7); mental retardation and delayed nervous system development: 15.1 (9.7 23.2); extrapyramidal disorders: 8.3 (4.5 14.8); sequelas of head injuries: 6.9 (3.5 13.1). RESULTS: These results, obtained using a modified version of a WHO protocol, together with dementia and the sequelas of head injuries, will permit the development of health policies and programmes for the control and treatment of neurological disorders prevalent in this region of Colombia

Effects of palm oil and dietary cholesterol on plasma lipoproteins: results from a dietary crossover trial in free-living subjects.

OBJECTIVE: To study the effects of palm oil (PO) and egg consumption (E) on plasma lipoproteins. DESIGN: Randomized crossover trial. SETTING: Free-living subjects. SUBJECTS: Twenty-eight healthy male students aged 20-34 y. INTERVENTIONS: Four typical Colombian diets (10 878 kJ/day; 57% energy in carbohydrates, 12% energy in proteins and 31% energy in fats) were consumed for 4 weeks. The HPOLC diet was high in PO (8.8% energy as palmitic acid, PA) and low in eggs (181.2 mg/kJ of dietary cholesterol, DC); the HPOHC diet was high in PO and high in eggs (866.1 mg/kJ of DC); the MPOMC diet was moderate in PO (6.3% energy as PA) and moderate in eggs (581.6 mg/kJ of DC); and the LOPOMC diet had no PO and was moderate in eggs (543.9 mg/kJ of DC). MAIN OUTCOME: Total (TC), low density (LDL-c), and high density lipoprotein cholesterol (HDL-c), and triacylglycerols (TAG) were measured on a pool of three fasting blood samples collected in consecutive days the last week of each diet. RESULTS: Comparison of the HPOHC and HPOLC diets showed increases in TC and LDL-c of 0.21 (P=0.01), and 0.16 mmol/l (P=0.05). Comparison of LOPOMC and MPOMC diets showed increases in TC and LDL-c of 0.39 (P<0.001), and 0.38 mmol/l (P<0.001), respectively. No significant changes in HDL-c or TAG were observed. CONCLUSIONS: Our findings suggest that non-extreme short-term changes in PO and DC consumption lead to significant elevations in plasma TC and LDL-c. SPONSORSHIP: CENIPALMA, Fundación Cardiovascular del Oriente Colombiano, Universidad Industrial de Santander.

Is C-reactive protein an independent risk factor for essential hypertension?

CONTEXT: C-reactive protein (CRP), predicts coronary heart disease incidence in healthy subjects and has been associated with decreased endothelium-dependent relaxation, a potential risk factor for hypertension. However, the relationship between CRP and hypertension has not been studied. OBJECTIVE: To assess whether circulating levels of CRP are independently related to essential hypertension. DESIGN: Cross-sectional population survey. We measured circulating levels of CRP, blood pressure and cardiovascular risk factors among participants. Binomial regression was used to calculate the adjusted effect of CRP on the prevalence of hypertension. SETTING: General community of Bucaramanga, Colombia. PARTICIPANTS: A random sample of 300 subjects > or = 30 years old. MAIN OUTCOME MEASURE: Arterial blood pressure. RESULTS: Overall hypertension prevalence was 46.0%. The unadjusted prevalence of hypertension was 58.7% in the highest quartile of CRP, but only 34.7% in the lowest quartile. After adjustment for age, sex, body mass index, family history of hypertension, fasting glycemia, sedentary behaviour, and alcohol consumption, the prevalence of hypertension was 1.14 [95% confidence interval (CI), 0.82, 1.58; P= 0.442], 1.36 (95% CI, 0.99, 1.87; P= 0.057) and 1.56 (95% CI, 1.14, 2.13; P = 0.005) times higher in subjects in the second, third and fourth quartiles of CRP, as compared to subjects in the first quartile. CONCLUSIONS: Our results suggest, for the first time, that CRP level may be an independent risk factor for the development of hypertension. However, because of the cross-sectional nature of our study, this finding should be confirmed in prospective cohort studies, aimed at elucidating the role of CRP in the prediction, diagnosis and management of hypertension.

Dental care associated with an outbreak of HIV infection among dialysis patients.

An outbreak of 14 cases of human immunodeficiency virus (HIV) infection was discovered by chance in May 1993 among hemodialysis patients at a university hospital in Bucaramanga, Colombia. The outbreak occurred in 1992. Stored sera were used to establish the probable period of infection (PPI) for 10 of the 14 cases. A nested case-control study was carried out to evaluate possible transmission mechanisms. The health care experience of each HIV-positive patient during that patient's PPI was compared to the experience of time-matched controls. Only invasive dental procedures were significantly associated with the risk of infection. Patients upon whom invasive dental procedures were performed during their PPIs had an average risk of HIV infection 8.15 times greater than comparable controls (P = 0.006), and seven out of nine cases of HIV infection with known PPIs in 1992 had an invasive dental procedure performed one to six months before seroconversion. None of the dental care personnel were found to be infected. Based on the available evidence, it seems most likely that the infection was transmitted from patient to patient by contaminated dental instruments.

[Factors associated with the initiation of breast feeding by women in the Dominican Republic]. / Factores associados al inicio de la lactancia materna en mujeres dominicanas.

The determinants of initiating breast-feeding vary among different populations, but knowledge of them is of fundamental importance for guiding programs to promote breast-feeding. Data from the Demographic and Health Survey of 1991 in the Dominican Republic were used to identify factors associated with the initiation of breast-feeding in a random sample of women of reproductive age. Approximately 93% of 2,714 mothers reported having begun to breast-feed their last live-born child who was currently under 5 years of age, and that percentage had not changed substantially in the past 5 years. A logistic regression analysis was done in which odd ratios (psi) were calculated as measures of association. Women who had suffered some type of illness during pregnancy (psi = 2.3), those whose child had a low birthweight (psi = 2.9), primiparas (psi = 1.9), and those with medium (psi = 1.6) or high (psi = 2.1) income levels showed a significantly higher risk of not starting to breast-feed. These women should be considered priority groups by breast-feeding promotion programs.

[Duration of breast-feeding in the Dominican Republic]. / Duracíon de la lactancia materna en la República Dominicana.

The present study reanalyzed data from the Dominican Republic National Health Survey, conducted in 1991, in order to identify the socioeconomic characteristics and the factors related to medical care, the pregnancy, and the child which influenced the total duration of breast-feeding (TDBF). A representative sample of 1984 mother-infant pairs was studied. Of the children of each mother, only the last one who was breast-fed and was less than three years old at the time of the survey was included. Data on TDBF and the factors studied were collected by interviewing the mothers. The risk of having been weaned at various ages was calculated by means of a life table, and the independent effect of each variable of interest was estimated using Cox's regression model. The median TDBF was 7 months and the relative weaning rate (RWR) was higher among weaned children (RWR = 8.56; 95%CI: 4.25-17.20), those whose mothers had a university education (RWR = 1.48; 95%CI: 1.24-1.77), those who began to suckle late (RWR = 1.25; 95%CI: 1.11-1.40), those who were born in public institutions (RWR = 1.62; 95%CI: 1.24-2.11) and private institutions (RWR = 2.19; 95%CI: 1.65-2.91), and those born to first-time mothers of a low socioeconomic level (RWR = 1.80; 95%CI: 1.45-2.24). Among the strategies of programs to promote breast-feeding, the importance of delayed weaning should be underscored, since this factor has the greatest influence on duration of breast-feeding.