Lina María Vera

Independent association between inflammatory markers (C-reactive protein, interleukin-6, and TNF-α) 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-α), has not been evaluated in well-controlled studies. We examined the cross-sectional relationship between IL-6, TNF-α, 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 ⩾140 and/or diastolic BP ⩾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-α 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-α 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.

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 ⩾ 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.

Prevalence and impact of cardiovascular risk factors in Bucaramanga, Colombia: results from the Countrywide Integrated Noncommunicable Disease Intervention Programme (CINDI/CARMEN) baseline survey

Background Although cardiovascular diseases are the main cause of death in the region, there are few data on the prevalence of cardiovascular risk factors in Latin American. We studied the distribution and impact of cardiovascular risk factors in Bucaramanga, Colombia. Methods We conducted a cross-sectional study in a random sample of 2989 subjects 15–64 years old. Population attributable risks were estimated from Framingham risk scores. Results Smoking prevalence was 16.2% (men 26.3%; women 10.5%). Hypertension prevalence was 9.9% in women and 8.8% in men, but reached 50% in those 60–64 years old. After adjustment for body mass index, men were more likely to be hypertensive, but only if under 40 years old. Obesity was more frequent in women (15.7%) than in men (8.7%), even after age-adjustment. About 46% of the participants were overweight or obese. Women also had higher prevalence of high total cholesterol (19.7 versus 15.7%) and high low-density lipoprotein-cholesterol (23.9 versus 19.5%), but lower prevalence of low high-density lipoprotein (HDL)-cholesterol (22.2 versus 37.6%). Only low-HDL prevalence was significantly different after body mass index and age-adjustment. The prevalence of diabetes was similar in men and women (4%), but age and body mass index-adjusted impaired fasting glucose prevalence was 60% higher in women. Population attributable risks were larger and similar for high total cholesterol, hypertension, and large waist-to-hip ratio (19%). Conclusions Women had higher prevalence of all risk factors with the exception of smoking and low-HDL. Reduction in cholesterol levels, blood pressure and obesity is a priority to control the ongoing epidemic of cardiovascular diseases in this population.

Ontogeny of the Circadian System During Embryogenesis in Rainbow Trout (Oncorhynchus mykyss) and the Effect of Prolonged Exposure to Continuous Illumination on Daily Rhythms of per1, clock, and aanat2 Expression

It is widely held that the development of the circadian system during embryogenesis is important for future survival of an organism. Work in teleosts has been, to date, limited to zebrafish, which provides little insight into the diversity of this system within such a large vertebrate class. In this study, the authors analyzed the diel expression of per1, clock, and aanat2 in unfertilized rainbow trout oocytes and embryos maintained under either a 12:12-h light:dark (LD) cycle or continuous illumination (LL) from fertilization. 24-h profiles in expression were measured at fertilization as well as 8, 21 42, and 57 days postfertilization (dpf). Both per1 and clock were expressed in unfertilized oocytes and all embryonic stages, whereas aanat2 expression was only measureable from 8 dpf. A reduction in both per1 and clock mean expression levels between unfertilized oocytes/0–1 dpf embryos and 8–9 dpf embryos was suggestive of a transition from maternal RNA to endogenous mRNA expression. Although aanat2 expression was not clearly associated with photic conditions, photoperiod treatment did alter the expression of per1 and clock expression/rhythmicity from as early as 8 dpf (per1), which could suggest the presence and functionality of an as yet unidentified “photoreceptor.” As a whole, this work demonstrates that clock systems are present and functional during embryonic development in rainbow trout. Further studies of their expression and regulation will help understand how the environment interacts with embryonic development in the species. (Author correspondence: andrew.davie@stir.ac.uk)

Antihypertensive Effects of Aspirin: What is the Evidence?

Nonsteroidal anti-inflammatory drugs are known to increase blood pressure and blunt the effect of antihypertensive drugs. Surprisingly, it has been suggested recently that aspirin lowers blood pressure and could be used for preventing hypertension. This review summarizes published data on the effects of aspirin on blood pressure. Trials suggesting that aspirin administered at bedtime lowers blood pressure are uncontrolled, unmasked, and potentially biased. They also conflict with cohort studies showing an 18% increase in the risk of hypertension among aspirin users. Fortunately, short-term use of aspirin does not seem to interfere with antihypertensive drugs. Regardless of its effect on blood pressure, low-dose aspirin effectively prevents cardiovascular events in patients with and without hypertension, but its benefits should be carefully weighed against a potential increase in the risk of adverse effects such as gastric bleeding and hemorrhagic stroke, as well as a small increase in the risk of hypertension.

Environmental and occupational health research and training needs in Colombia: A Delphi study

INTRODUCTION Environmental factors contribute with 16% of the burden of disease in Colombia. A main obstacle in implementing national and regional environmental and occupational health policies is the limited knowledge on the local ability to study and control the impact of harmful exposures on health. OBJECTIVE To identify needs for research and training in environmental and occupational health in Colombia. MATERIALS AND METHODS We conducted a three-round hybrid Delphi study. A group of environmental and occupational health Colombian experts (n=16) from government agencies, universities, and research centers was recruited to participate in the study. Expert´s opinions on research and training needs were gathered through online questionnaires, followed by an in-person meeting. The percentage of agreement and the coefficient of variation were used to measure consensus. RESULTS Air pollution and chemical products were considered the most important environmental and occupational exposures, due to their significant impact on chronic non-communicable diseases, such as respiratory diseases, cardiovascular diseases, and cancer. Research on the effects of outdoor air pollution on cardiovascular and respiratory diseases was considered of the greatest importance. Priority training areas included environmental and occupational health risk assessment, exposure modeling, advanced statistical methods, urban planning, occupational safety and hygiene, and epidemiology and toxicology. CONCLUSIONS These findings provide a valuable input for the definition and implementation of national environmental and occupational health policies and for the development of a regional hub aimed at strengthening the capacity for research and training in Colombia.