Association between preoperative blood pressure and outcomes in cardiac surgery: results of a prospectively planned cohort study

BACKGROUND

It is unknown whether unwitnessed BP (UBP) measurement or ambulatory BP (ABP) monitoring improves the prediction of adverse events estimated by risk scores. We intended to study associations between preoperative BP measured through these two methods and the incidence of adverse outcomes in patients undergoing cardiac surgery.

METHODS

We included a cohort of 167 patients undergoing elective or urgent cardiac surgeries. Preoperative BP was measured by UBP and 24-hour ABP. Primary outcome was the combination of mortality from any cause, nonfatal myocardial infarction, nonfatal stroke, new hospital admission, and dialysis occurring within 30 days after surgery. The associations between preoperative BP and surgical outcomes were tested using the Chi-square test and Analysis of Variance. A generalized linear model with a logistic link function and a robust estimator was used to adjust for the EuroScore-II risk estimation.

RESULTS

The incidence of the primary outcome increased in parallel with the quartiles of the 24-hour ABP in participants submitted to CABG: 10% in the first quartile, 13% in the second, 37% in the third, and 53% in the fourth quartile (P for trend<0.01). Quartiles of overnight ABP were also significantly associated with postoperative complications in patients undergoing CABG (P=0.04). The risks in CABG patients were independent of the EuroScore-II. There was no association between BP and outcomes in patients submitted to other surgeries.

CONCLUSIONS

High preoperative BP measured by ABP monitoring is a risk factor for postoperative complications in patients submitted to CABG.

The Effect of Alcohol on Blood Pressure and Hypertension

PURPOSE

To examine the acute and chronic effects of alcohol on blood pressure (BP) and the incidence of hypertension. We discuss the most current understanding of the mechanisms underlining these effects and their associations with the putative cardioprotective effects of consumption of low-to-moderate amounts of alcoholic beverages.

RECENT FINDINGS

A recent meta-analysis confirmed findings of experimental studies, demonstrating an acute biphasic effect of ethanol on BP, decreasing up to 12 h of ingestion and increasing after that. This effect is mediated by vagal inhibition and sympathetic activation. A meta-analysis found that chronic consumption of alcoholic beverages was associated with a high incidence of hypertension in men and women; it also found that, in women, the risk begins at moderate alcohol consumption. The risks of alcohol consumption are higher in Blacks than in Asians or Caucasians. The mechanism underlying the chronic effects of alcohol on BP, and particularly the differential effect on Blacks, is still unknown. Short-term trials showed that alcohol withdrawal promotes BP reduction; however, the long-term effectiveness of interventions that aim to lower BP through the restriction of alcohol consumption has not been demonstrated. The harmful effects of alcohol on BP do not support the putative cardioprotective effect of low-to-moderate consumption of alcoholic beverages. The absence of a tangible mechanism of protection, and the possibility that this beneficial effect is biased by socioeconomic and other characteristics of drinkers and abstainers, calls into question the hypothesis that consuming low amounts of alcoholic beverages improves cardiovascular health. The evidence from investigations with various designs converge regarding the acute biphasic effect of ethanol on BP and the risk of chronic consumption on the incidence of hypertension, particularly for Blacks. These effects do not support the putative cardioprotective effect of consumption of low-to-moderate amounts of alcoholic beverages. Mechanisms of chronic BP increase and the demonstration of long-term benefits of reducing alcohol intake as a means to treat hypertension remain open questions.

Renin-Angiotensin-Aldosterone System Inhibitors in COVID-19: A Review

Among the multiple uncertainties surrounding the novel coronavirus disease (COVID-19) pandemic, a research letter published in The Lancet implicated drugs that antagonize the renin-angiotensin-aldosterone system (RAAS) in an unfavorable prognosis of COVID-19. This report prompted investigations to identify mechanisms by which blocking angiotensin-converting enzyme 2 (ACE2) could lead to serious consequences in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The possible association between RAAS inhibitors use and unfavorable prognosis in this disease may have been biased by the presence of underlying cardiovascular diseases. As the number of COVID-19 cases has increased worldwide, it has now become possible to investigate the association between RAAS inhibitors and unfavorable prognosis in larger cohorts. Observational studies and one randomized clinical trial failed to identify any consistent association between the use of these drugs and unfavorable prognosis in COVID-19. In view of the accumulated clinical evidence, several scientific societies recommend that treatment with RAAS inhibitors should not be discontinued in patients diagnosed with COVID-19 (unless contraindicated). This recommendation should be followed by clinicians and patients.

Early Manipulation of Arterial Blood Pressure in Acute Ischemic Stroke (MAPAS): Results of a Randomized Controlled Trial

INTRODUCTION

There is uncertainty over the optimal level of systolic blood pressure (SBP) in the setting of acute ischemic stroke (AIS). The aim of this study was to determine the efficacy of the early manipulation of SBP in non-thrombolised patients. The key hypothesis under investigation was that clinical outcomes vary across ranges of SBP in AIS.

METHODS

218 patients were randomized within 12 h of AIS to maintain the SBP during 24 h within three ranges: Group 1 140-160 mmHg, Group 2 161-180 mmHg or Group 3 181-200 mmHg. Vasoactive drugs and fluids were used to achieve these targets. Good outcome was defined as a modified Rankin score 0-2 at 90-days.

RESULTS

The median SBP in the three groups in 24 h was: 153 mmHg, 163 mmHg, and 178 mmHg, respectively, P < 0.0001. Good clinical outcome did not differ among the different groups (51% vs 52% vs 39%, P = 0.27). Symptomatic intracranial hemorrhage (SICH) was more frequent in the higher SBP range (1% vs 2.7% vs 9.1%, P = 0.048) with similar mortality rates. No patient had acute neurological deterioration related to the SBP reduction in the first 24 h. In our logistic regression analysis, the odds of having good clinical outcome was higher in Group 2 (OR 2.83) after adjusting for important confounders. Regardless of the assigned group, the probability of good outcome was 47% in patients who were manipulated to increase the BP, 42% to decrease and 62% in non-manipulated (P = 0.1). Adverse effects were limited to Group 2 (4%) and Group 3 (7.6%) and were associated with the use of norepinephrine (P = 0.05).

CONCLUSIONS

Good outcome in 90 days was not significantly different among the 3 blood pressure ranges. After logistic regression analysis, the odds of having good outcome was greater in Group 2 (SBP 161-180 mmHg). SICH occurred more frequently in Group 3 (181-200 mmHg).

Efficacy of chlorthalidone and hydrochlorothiazide in combination with amiloride in multiple doses on blood pressure in patients with primary hypertension: a protocol for a factorial randomized controlled trial

BACKGROUND

Thiazide diuretics have demonstrated favorable blood pressure lowering efficacy, but the equivalent doses of their more common agents, chlorthalidone and hydrochlorothiazide, are still unclear. Further, concerns exist regarding adverse metabolic effects, which may be attenuated with the concomitant administration of a potassium-sparing diuretic, such as amiloride. This trial aims to investigate the efficacy of chlorthalidone and hydrochlorothiazide, in combination with amiloride at different doses, for initial management of patients with primary hypertension.

METHODS/DESIGN

This is a factorial (2 × 2) randomized double-blinded clinical trial comparing the association of a thiazide diuretic (chlorthalidone 25 mg/day or hydrochlorothiazide 50 mg/day) with a potassium-sparing diuretic (amiloride 10 mg/day or amiloride 20 mg/day) in patients with primary hypertension. The primary outcome will be the mean change from baseline in 24-h systolic and diastolic blood pressure measured by ambulatory blood pressure monitoring. The secondary outcomes will be the mean change from baseline in daytime and nighttime systolic and diastolic blood pressure measured by ambulatory blood pressure monitoring, mean change from baseline in systolic and diastolic blood pressure measured by office blood pressure, incidence of adverse events, variation of laboratory parameters, and proportion of patients who achieved blood pressure control. The follow-up will last 12 weeks. For a P alpha of 0.05, power of 80%, standard deviation of 9 mmHg, and absolute difference of 6 mmHg on systolic blood pressure on 24-h ambulatory blood pressure monitoring, it will be necessary to study a total of 76 patients. The sample size will be increased by 10% to compensate for losses, resulting in 84 patients being randomized.

DISCUSSION

Diuretics are pivotal drugs for the treatment of hypertension. Chlorthalidone and hydrochlorothiazide, in combination with amiloride in multiple doses, will be tested in terms of blood pressure lowering efficacy and safety. Since the intensity of blood pressure reduction is the major determinant of reduction in cardiovascular risk in hypertensive patients, this study will help to determine which combination of diuretics represents the most appropriate treatment for this population.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03928145. Registered on 25 April 2019. Last update on 29 April 2019.

Effect of metformin on blood pressure in patients with hypertension: a randomized clinical trial

OBJECTIVE

Part of the beneficial effects of metformin on the prevention of cardiovascular events in diabetes can be attributed to pleiotropic effects, including a blood pressure (BP)-lowering effect. In a double-blind parallel clinical trial (NCT02072382), the effect of metformin on BP evaluated by ambulatory blood pressure monitoring (ABPM) was measured.

METHODS

Ninety-seven patients with hypertension, but without diabetes mellitus, were randomized to receive 850-1700 mg of metformin (n = 48) or placebo (n = 49). Clinical, laboratory, and ABPM data were collected at the baseline and after 8 weeks of follow-up.

RESULTS

The sample consisted mainly of White overweight women. There was no difference in BP reduction measured by ABPM between both groups. There was no effect in BP measured in the different periods of ABP monitoring and office BP. Additionally, fasting plasma glucose, lipids, and C-reactive protein remained unchanged during the trial. There was a significant reduction in waist circumference with metformin (95.1 ± 10.4 to 89.3 ± 27.4 cm; p = 0.02).

CONCLUSION

In the present trial, metformin did not reduce BP, measured by ABP monitoring, in hypertensive patients without diabetes.

Diuretics are Similar to Losartan on Echocardiographic Target-Organ Damage in Stage I Hypertension. PREVER-Treatment Study

Blood pressure (BP)-lowering therapy improves left ventricular (LV) parameters of hypertensive target-organ damage in stage II hypertension, but whether there is a drug-class difference in echocardiographic parameters in stage I hypertension patients is less often studied. In the PREVER treatment study, where individuals with stage I hypertension were randomized for treatment with diuretics (chlorthalidone/amiloride) or losartan, 110 participants accepted to participate in a sub-study, where two-dimensional echocardiograms were performed at baseline and after 18 months of antihypertensive treatment. As in the general study, systolic BP reduction was similar with diuretics or with losartan. Echocardiographic parameters showed small but significant changes in both treatment groups, with a favorable LV remodeling with antihypertensive treatment for 18 months when target blood pressure was achieved either with chlorthalidone/amiloride or with losartan as the initial treatment strategy. In conclusion, even in stage I hypertension, blood pressure reduction is associated with improvement in echocardiographic parameters, either with diuretics or losartan as first-drug regimens.

Partial anomalous pulmonary venous connection in a 72-year-old woman: A case report

Partial Anomalous Pulmonary Venous Connection is a congenital abnormality characterized by drainage of one or more, but not all, pulmonary veins to the right atrium or to one of the systemic veins. This pathology has low prevalence, although it probably is underestimated and is rarely diagnosed in adults. This report describes a case of a 72-year-old woman with long-term worsening shortness of breath and elevated pulmonary artery systolic pressure in which Partial Anomalous Pulmonary Venous Connection was occasionally diagnosed through imaging methods.

Disrupted day-night pattern of cardiovascular death in obstructive sleep apnea

BACKGROUND

Obstructive sleep apnea (OSA) patients who suffer sudden cardiac death die predominantly during the night. We aimed to investigate whether all cardiovascular-related deaths display the same night-time peak as sudden cardiac death.

METHODS

Data from a large cohort of adults who underwent full-night polysomnography between 1985 and 2015 in a university-affiliated sleep clinic were analyzed. Time and cause of death of these patients and of persons from the general population were identified in death certificates from the State Health Secretariat. The day-night pattern of cardiovascular death was compared among groups of non-OSA, OSA (apnea-hypopnea index, AHI ≥5), CPAP users, and persons from the general population.

RESULTS

Among 619 certificates, 160 cardiovascular-related deaths were identified. The time of death of the 142 persons with OSA was uniformly distributed over 24 h, with neither an identifiable peak nor a circadian pattern (Rayleigh test; P = 0.8); the same flat distribution was seen in those with purported CPAP use (n = 49). Non-OSA individuals presented a morning peak and a night nadir of deaths, clearer when analyzed in eight-hour intervals. The same pattern was observed in 92 836 certificates from the State general population, with cardiovascular deaths showing the expected morning peak, night nadir, and a significant circadian pattern (Rayleigh test; P < 0.001).

CONCLUSIONS

In OSA patients, the distribution of cardiovascular-related deaths throughout the 24-h period is virtually flat, in contrast with the described nighttime peak of sudden cardiac death. OSA-related phenomena during nighttime might be blunting the mechanisms, arrhythmic or not, behind the morning peak of cardiovascular-related deaths.

Blood pressure variability in controlled and uncontrolled blood pressure and its association with left ventricular hypertrophy and diastolic function

High systolic blood pressure (SBP) variability has been associated with higher risk for target-organ damage. In a cross-sectional study done in a tertiary outpatient hypertension clinic, we compared short-term SBP variability among controlled and uncontrolled hypertensive patients and evaluated the association between higher levels of SBP variability and diastolic function and left ventricular hypertrophy (LVH). Patients were evaluated by 24-h ambulatory blood pressure monitoring and transthoracic Doppler echocardiogram. Blood pressure (BP) variability was evaluated by the time-rate index and high variability corresponded to index values in the top quartile of distribution. Echocardiographic parameters were compared in patients with and without higher BP variability within controlled and uncontrolled office BP (⩽140/90 mm Hg). The analyses included 447 patients with 58±12 years of age, 67% were women, 68% white, 43% current or previous smokers and 32% with diabetes mellitus. Among the whole sample, 137 patients had controlled and 310 uncontrolled BP. The 75th percentile cutoff points for the time-rate index were 0.502 mm Hg min(-1) and 0.576 mm Hg min(-1) for participants with controlled and uncontrolled BP, respectively. After adjustment for confounders, the time-rate index did not differ between controlled and uncontrolled patients. BP variability was not associated with LVH or diastolic function in controlled and uncontrolled BP after adjustment for 24-h SBP and age. Patients with controlled and uncontrolled BP had similar SBP variability assessed by time-rate index, which was not associated with LVH or diastolic function. These findings should be confirmed in studies with larger sample size.

Preventing the progression of prehypertension to hypertension: role of antihypertensives

Recent guidelines for the diagnosis and management of hypertension reversed the historical trend to recommend lower blood pressure (BP) thresholds to diagnose hypertension in high-risk individuals, such as patients with diabetes and elderly patients. The decision to raise the BP thresholds for diagnosis of hypertension in patients with diabetes was mostly based on the findings of the ACCORD trial. Nonetheless, the results of the ACCORD trial are within the predicted benefit to prevent coronary artery disease and stroke by meta-analysis of randomized controlled trials (RCT), particularly in regard to the prevention of stroke. The Eighth Joint National Committee (JNC 8) did not address prehypertension. There are many RCT done in individuals with prehypertension and concomitant cardiovascular disease showing the benefit of treatment of these patients. Trials exploring the efficacy of interventions to prevent cardiovascular disease in individuals with prehypertension free of cardiovascular disease would be hardly feasible in face of the low absolute risk of these individuals. Considering the risks of prehypertension for cardiovascular disease and the fast progression to hypertension of a large proportion of individuals with prehypertension, it is worth to consider drug treatment for individuals with prehypertension. RCT showed that the progression to hypertension can be partially halted by BP-lowering agents. These and ongoing clinical trials are herein revised. Prehypertension may be a window of opportunity to prevent hypertension and its cardiovascular consequences.

Angiotensin receptor blockers for prevention of cardiovascular disease: where does the evidence stand?

Angiotensin receptor blockers (ARBs) are the most commonly used among blood pressure-lowering drugs worldwide, despite the absence of sound evidence of effectiveness in large and unbiased clinical trials. Meta-analyses published in recent years and reviewed here have not given support to this preference, suggesting that ARBs may be ineffective in the prevention of all cause mortality and major cardiovascular events (particularly myocardial infarction). There is evidence that ARB can be harmful for the kidney, particularly in patients with diabetes and in the elderly. It may be time to call for a moratorium on the preference for ARB in the management of hypertension and in patients with high cardiovascular risk.

Seasonal variation in food intake and the interaction effects of sex and age among adults in southern Brazil

BACKGROUND/OBJECTIVES

Because studies have evidenced variations in nutrient intake, further investigation of the interaction between demographic characteristics and the seasons is necessary. We aimed to test the differences in food intake throughout the seasons and the interaction between the seasons and sex and age.

SUBJECTS/METHODS

This study included 273 individuals. Food intake was evaluated with 24-hour dietary recalls, and the reported food items were sorted into food groups. We performed the test on the differences in intake of food groups throughout the seasons with repeated measures and on the interaction effect by using the Generalized Estimate Equation.

RESULTS

Intake of fruits and natural fruit juices and sweetened beverages was lower, whereas that of grains and derivatives was higher in the winter. The intake of leafy vegetables and fish and seafood was lower in the autumn. The consumption of coffee and eggs was higher in the spring. Intake of chocolate powder and sugar, salt and lean poultry was higher in the winter. The variation in consumption of grains and derivatives, eggs, fatty poultry and processed meat over the seasons was more likely to be modified by sex. Age interacted with the seasons for leafy vegetables, beans and lentils, lean beef, lean poultry, low fat milk and light yogurt, vegetable oil and unsalted margarine, chocolate powder and sugar and processed meat.

CONCLUSIONS

This study shows that food intake may change seasonally and that seasonal variation depends on sex and age, which might aggregate a specific co-variation component.

The effect of antihypertensive agents on sleep apnea: protocol for a randomized controlled trial

BACKGROUND

Obstructive sleep apnea (OSA) and hypertension are well-known cardiovascular risk factors. Their control could reduce the burden of heart disease across populations. Several drugs are used to control hypertension, but the only consistently effective treatment of OSA is continuous positive airway pressure. The identification of a drug capable of improving OSA and hypertension simultaneously would provide a novel approach in the treatment of both diseases.

METHODS/DESIGN

This is a randomized double-blind clinical trial, comparing the use of chlorthalidone with amiloride versus amlodipine as a first drug option in patients older than 40 years of age with stage I hypertension (140 to 159/90 to 99 mmHg) and moderate OSA (15 to 30 apneas/hour of sleep). The primary outcomes are the variation of the number of apneas per hour and blood pressure measured by ambulatory blood pressure monitoring. The secondary outcomes are adverse events, somnolence scale (Epworth), ventilatory parameters and C reactive protein levels. The follow-up will last 8 weeks. There will be 29 participants per group. The project has been approved by the ethics committee of our institution.

DISCUSSION

The role of fluid retention in OSA has been known for several decades. The use of diuretics are well established in treating hypertension but have never been appropriately tested for sleep apnea. As well as testing the efficacy of these drugs, this study will help to understand the mechanisms that link hypertension and sleep apnea and their treatment.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01896661.

Blood pressure targets in the treatment of high blood pressure: a reappraisal of the J-shaped phenomenon

The risk that lowering blood pressure (BP) excessively increases the incidence of cardiovascular disease-the J-shaped phenomenon-has been a matter of concern endorsed by many experts, particularly in patients with coronary heart disease and diabetes. The results of the Action to Control Cardiovascular Risk in Type 2 Diabetes (ACCORD) trial strengthened the idea that it may be futile to lower BP more intensively in patients with diabetes. Nevertheless, there seems to be no direct J-shaped relation between BP-lowering treatment and outcome. Patients with normal or low BP and high or very high cardiovascular risk could have their BP reduced further by treatment. Placebo-controlled clinical trials of BP-lowering agents in patients with BP within normal values and concomitant cardiovascular disease demonstrated consistent reduction of recurrent and newer cardiovascular events. The use of BP agents in such conditions, as in patients with coronary artery disease, heart failure, diabetes and in patients recovered from a stroke has been endorsed by guidelines. Although is likely that there is a J-shaped relationship of BP with outcomes in cohort studies, clinical trials that tested more intensive versus standard goals and clinical trials done with patients with low BP demonstrated that the J-shaped phenomenon should not be a concern in the treatment of high BP.

Population-attributable risks for ischemic stroke in a community in South Brazil: a case-control study

Background

Risk factors for ischemic stroke are mostly known, but it is still unclear in most countries, what are their combined population-attributable risk percent (PAR%). In a case-control study the individual odds ratios (ORs) and the individual and combined PAR%, including risk factors not addressed in previous studies were estimated.

Methods

Cases and controls were selected from patients attending to an emergency department. Cases were patients aged with 45 years or more with the first episode of ischemic stroke, characterized by a focal neurological deficit or change in the mental status occurring during the previous 24 hours. Controls, matched to cases by age and gender, were selected from patients without neurological complaints.

Results

133 cases and 272 controls were studied. Odds ratios for ischemic stroke were: atrial fibrillation (27.3; CI 95% 7.5–99.9), left ventricular hypertrophy (20.3; CI 95% 8.8–46.4), history of hypertension (11.2; CI 95% 5.4–23.3), physical inactivity (6.6; CI 95% 3.3–13.1), low levels of HDL-cholesterol (5.0; CI 95%2.8–8.9), heavy smoking (2.8; CI 95% 1.5–5.0), carotid bruit (2.5; CI 95% 1.3–4.6), diabetes (2.4; CI 95% 1.4–4.0) and alcohol abuse (2.1; CI 95% 1.1–4.0), The combination of these risk factors accounted for 98.9% (95% CI; 96.4%–99.7%) of the PAR% for all stroke.

Conclusions

Nine risk factors, easily identified, explain almost 100% of the population attributable risk for ischemic stroke.

Prehypertension: the rationale for early drug therapy

Blood pressure within prehypertensive levels confers higher cardiovascular risk by two means. At first, these levels are associated with higher risk for cardiovascular events, starting at BP values as low as 115/75 mmHg, and doubling at each 20 mmHg for systolic or 10 mmHg for diastolic BP. Prehypertension is also an intermediate stage for full hypertension, which develops in an annual rate of 7 out 100 individuals with 40-50 years of age. The precocious drug intervention in patients with prehypertension is therefore appealing. In individuals with previous cardiovascular disease or diabetes the use of BP-lowering agents is compulsory, since the 18-42% reduction of major cardiovascular events demonstrated in randomized clinical trials translates in palpable clinical benefit. In the absence of higher baseline risk, the absolute benefit of treatment is presumably small and was not demonstrated to date. These individuals could be candidate to treatment with the aim to prevent the development of full hypertension. The long-lasting effectiveness of non-drug therapies is low outside the controlled conditions of randomized clinical trials, and there are evidences that the use of BP-lowering drugs reduces the incidence of hypertension in individuals with prehypertension by more than 60%. Clinical trials testing the efficacy and safety of BP agents to prevent hypertension in a population-based perspective are required. In the meantime, it is worthy to present the option to start low doses of BP agents for individuals with prehypertension without co-morbidities who do not respond to the prescription of lifestyle modification.

Risk factors for cardiovascular disease in the very elderly: results of a cohort study in a city in southern Brazil

BACKGROUND

Risk factors for cardiovascular mortality have barely been investigated in very elderly persons and there may be differences compared with younger individuals.

METHODS

This is a cohort study of all inhabitants over 80 years of age in the city of Veranópolis, Brazil. The association of demographic, anthropometric, physical, and medical characteristics with mortality by any cause and by cardiovascular disease (CVD) was investigated by means of Cox regression models.

RESULTS

The mean age of the participants was 83.6 ± 3.3 years. Vital status and cause of death was ascertained in 96.9% of the participants after a mean follow-up of 8.7 ± 3.8 years. Systolic and diastolic blood pressure showed a U-shape relationship with cardiovascular and total mortality. Blood pressure lower than 140/90 mmHg was associated with a higher risk for cardiovascular mortality (HR 4.76, 95% CI 1.56-14.28, p = 0.006). Duration of sleep was inversely associated with the risk of cardiovascular death (HR 0.83, 95% CI 0.73-0.95, p = 0.007), while apoA-I was inversely associated only with the risk of all-cause mortality (HR 0.99, 95% CI 0.98-1.00, p = 0.041). Anthropometric indexes, smoking, cholesterol, LDL-cholesterol, HDL-cholesterol, and other traditional risk factors were not associated with cardiovascular mortality.

CONCLUSION

Many traditional risk factors are not associated with cardiovascular mortality in the very elderly. Longer sleep duration is associated with lower cardiovascular mortality of very elderly individuals, while low blood pressure identifies very elderly individuals at higher risk of dying from cardiovascular causes.

Shift work is not associated with high blood pressure or prevalence of hypertension

Background

Working mostly at night has been suggested to be associated with upset of chronobiological rhythms and high blood pressure, but the evidence from epidemiological studies is weak.

Methods

In a cross-sectional survey, we evaluated the association between shift work and blood pressure, pre-hypertension and hypertension. In total, 493 nurses, nurse technicians and assistants, were selected at random in a large general hospital setting. Hypertension was diagnosed by the mean of four automatic blood pressure readings ≥140/90 mmHg or use of blood pressure lowering agents, and pre-hypertension by systolic blood pressure ≥120–139 or diastolic blood pressure ≥80–89 mmHg. Risk factors for hypertension were evaluated by a standardized questionnaire and anthropometric measurements. The association between the shift of work and blood pressure, pre-hypertension and hypertension was explored using univariate and multivariate analyses that controlled for risk factors for hypertension by covariance analysis and modified Poisson regression.

Results

The mean age of the participants was 34.3±9.4 years and 88.2% were women. Night shift workers were older, more frequently married or divorced, and less educated. The prevalence of hypertension in the whole sample was 16%, and 28% had pre-hypertension. Blood pressure (after adjustment for confounding) was not different in day and night shift workers. The prevalence of hypertension and pre-hypertension by shift work was not different in the univariate analysis and after adjustment for confounding (all risk ratios  = 1.0).

Conclusion

Night shift work did not increase blood pressure and was not associated with hypertension or pre-hypertension in nursing personnel working in a large general hospital.

Does the blood pressure-lowering effect of statins contribute to their beneficial cardiovascular effects?

Not all cardiovascular protection provided by statins is explained by their beneficial effects on lipoproteins. Old (e.g., clofibrate) and new (e.g., torcetrapib and ezetimibe) agents, with similar or more intense beneficial effect over lipoproteins, do not reproduce the beneficial effects of statins. Besides their anti-inflammatory and other pleiotropic effects, a blood pressure-lowering effect could be an additional mechanism of cardiovascular protection of statins. Large trials of statins in the primary and secondary prevention of cardiovascular disease did not report an effect on blood pressure, but the use of blood pressure-lowering agents was left to the discretion of physicians during the trial. Post hoc analyses of small trials and a meta-analysis of some of them have suggested that statins could lower systolic blood pressure by approximately 4 mmHg, particularly in patients with high blood pressure. Most studies, however, had small samples and were not blinded. Others had a cross-over or observational design. The overall view of these studies rules out a substantial blood pressure-lowering effect of statins. An effect restricted to subjects with high blood pressure could ultimately derive from the anti-inflammatory effect of statins, since higher levels of C-reactive protein are associated with higher blood pressure. An unequivocal demonstration of an antihypertensive effect of statins, however, is still lacking, and a randomized trial with enough power to evaluate blood pressure variation in a large range of blood pressure values is required to demonstrate whether statins definitely have an antihypertensive effect.

The corporate bias and the molding of prescription practices: the case of hypertension

Drug management of hypertension has been a noticeable example of the influence of the pharmaceutical industry on prescription practices. The worldwide leading brands of blood pressure-lowering agents are angiotensin receptor-blocking agents, although they are considered to be simply substitutes of angiotensin-converting enzyme (ACE) inhibitors. Commercial strategies have been based on the results of clinical trials sponsored by drug companies. Most of them presented distortions in their planning, presentation or interpretation that favored the drugs from the sponsor, i.e., corporate bias. Atenolol, an ineffective blood pressure agent in elderly individuals, was the comparator drug in several trials. In a re-analysis of the INSIGHT trial, deaths appeared to have been counted twice. The LIFE trial appears in the title of more than 120 reproductions of the main and flawed trial, as a massive strategy of scientific marketing. Most guidelines have incorporated the corporate bias from the original studies, and the evidence from better designed studies, such as the ALLHAT trial, have been largely ignored. In trials published recently corporate influences have touched on ethical limits. In the ADVANCE trial, elderly patients with type 2 diabetes and cardiovascular disease or risk factors, allocated to placebo, were not allowed to use diuretic and full doses of an ACE inhibitor, despite the sound evidence of benefit demonstrated in previous trials. As a consequence, they had a 14% higher mortality rate than the participants allocated to the active treatment arm. This reality should be modified immediately, and a greater independence of the academy from the pharmaceutical industry is necessary.

Diuretics: still essential drugs for the management of hypertension

According to most current international guidelines for hypertension, diuretics are indicated for elderly and black patients, unless they have any of a long list of other preferential indications. These recommendations are mostly based on the results of corporate-sponsored and biased trials, which have unsuccessfully tried to demonstrate the existence of pleiotropic effects of newer agents. Metaregression analyses have shown that the benefits of treatments are directly proportional to the difference in blood pressure between trial arms. New analyses of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack (ALLHAT) trial demonstrated the superiority of chlorthalidone over other agents in the prevention of end-stage renal disease in diabetics and of cardiovascular events in newer cases of diabetes. Despite this evidence, patients continue to withdraw from effective therapies in recent trials. The use of diuretics has also been challenged by the results of the Avoiding Cardiovascular Events in Combination Therapy in Patients Living with Systolic Hypertension (ACCOMPLISH) trial, which employed hydrochlorothiazide, a diuretic with lower potency and duration of action than chlorthalidone. Diuretics are still essential drugs for hypertension management, but diuretics with higher potency and duration of action, such as chlorthalidone, should be preferred.

Diagnosis of obstructive sleep apnea syndrome and its outcomes with home portable monitoring

BACKGROUND

The use of portable respiratory monitoring (PM) has been proposed for the diagnosis of obstructive sleep apnea syndrome (OSAS), but most studies that validate PM accuracy have not followed the best standards for diagnostic test validation. The objective of the present study was to evaluate the accuracy of PM performed at home to diagnose OSAS and its outcomes after first validating PM in the laboratory setting by comparing it to polysomnography (PSG).

METHODS

Patients with suspected OSAS were submitted, in random order, to PM at the sleep laboratory concurrently with PSG (lab-PM) or at home-PM. The diagnostic performance was assessed by sensitivity, specificity, positive and negative predictive values, positive likelihood ratio (+LR), negative likelihood ratio (-LR), intraclass correlation coefficients, kappa statistic, and Bland-Altman plot.

RESULTS

One hundred fifty-seven subjects (73% men, mean age +/- SD, 45 +/- 12 yr) with an apnea-hypopnea index (AHI) of 31 (SD +/- 29) events/h were studied. Excluding inadequate recordings, 149 valid comparisons with lab-PM and 121 with unattended home-PM were obtained. Compared to PSG for detecting AHI > 5, the lab-PM demonstrated sensitivity of 95.3%, specificity of 75%, +LR of 3.8, and -LR of 0.11; the home-PM exhibited sensitivity of 96%, specificity of 64%, +LR of 2.7, and -LR of 0.05. Kappa statistics indicated substantial correlation between PSG and PM results. Bland-Altman plot showed smaller dispersion for lab-PM than for home-PM. Pearson product moment correlation coefficients among the three AHIs and clinical outcomes were similar, denoting comparable diagnostic ability.

CONCLUSIONS

This study used all available comparison methods to demonstrate accuracy of PM in-home recordings similar to that of repeated PSGs. PM increases the possibility of correctly diagnosing and effectively treating OSAS in populations worldwide.

Association between pregnancy-related hypertension and severity of hypertension

Hypertension in pregnancy is an emerging sex-specific risk factor for cardiovascular disease and may lead to more severe hypertension after pregnancy. The objectives of this study were to investigate the frequency of pregnancy-related hypertension among patients referred to a hypertension clinic and its association with the severity of hypertension and evidence of end-organ damage. In this cross-sectional study, women with hypertension were submitted to a systematic clinical evaluation. The occurrence of pregnancy-related hypertension was investigated by questionnaire. The association between pregnancy-related hypertension and severity of hypertension (stage 2 according to Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VII)) and end-organ damage was assessed in a logistic regression model. The mean age, systolic and diastolic blood pressure and body mass index (BMI) of the 768 women examined were 51.6+/-12.7 years, 158.2+/-26.6 mm Hg, 93.8+/-14.3 mm Hg and 29.4+/-5.6 kg/m(2), respectively. The proportion of women with pregnancy-related hypertension was 32.9%. It was significantly associated with hypertension at stage 2 (OR: 1.60, 95% CI: 1.14-2.24; P=0.01) after controlling for confounders. The occurrence of a pregnancy-related hypertension was not associated with evidence of optic fundi abnormalities, left ventricular hypertrophy or abnormalities in kidney function. In conclusion, pregnancy-related hypertension is frequent in women referred to a hypertension clinic, and is associated with severe hypertension but not with evidence of end-organ damage.

Does psychosocial stress cause hypertension? A systematic review of observational studies

Acute stress promotes transient elevation of blood pressure, but there is no consistent evidence that this effect results in hypertension. In this systematic review of cohort and case-control studies that investigated the association between psychosocial stress and hypertension, we conducted a complete search up to February 2007 in MEDLINE, EMBASE, PSYCINFO and LILACS, through a search strategy that included eight terms to describe the exposure, six related to the design of the studies and one term for outcome. The quality was assessed by the Newcastle-Ottawa Quality Assessment Scale. The selection was done in duplicate by two teams of independent reviewers. Among 82 studies selected in the second phase, only 14 (10 cohort studies and 4 case-control studies), totalling 52,049 individuals, fulfilled the selection criteria. The average quality of the studies was 6.6+/-1.3 in a 9-point scale. Acute life events were associated with hypertension in one and were not associated in two studies. Five out of seven studies found a significant and positive association between measures of chronic stress and hypertension, with risk ratios ranging from 0.8 to 11.1. Three out of five studies reported high and significant risks of affective response to stress for hypertension, one a significant risk close to a unit and one reported absence of risk. Acute stress is probably not a risk factor for hypertension. Chronic stress and particularly the non-adaptive response to stress are more likely causes of sustained elevation of blood pressure. Studies with better quality are warranted.

Risk factors for hepatitis C virus infection in individuals infected with the HIV

BACKGROUND

Except for injecting drug use, other routes of transmission for hepatitis C virus among HIV-AIDS patients have not been consistently described, and risk estimates are often not adjusted for confounding factors.

AIMS

To evaluate characteristics associated with hepatitis C virus infection in individuals infected with the HIV.

PATIENTS

Cases were patients co-infected by HIV and hepatitis C virus, and controls were infected only by HIV.

METHODS

Cases and controls were consecutively enrolled at a public health care outpatient HIV-AIDS reference centre in Porto Alegre, Southern Brazil.

RESULTS

A total of 227 cases (63% men; 40.3+/-8.7 years) and 370 controls (44.6% men; 38.9+/-9.8 years) were enrolled in the study. In a multiple logistic regression model, male gender (odds ratio 1.9; 95% confidence interval 1.3-2.7), age between 30 and 49 years (odds ratio 2.1; 95% confidence interval 1.2-3.7), elementary school education (odds ratio 4.2; 95% confidence interval 1.9-9.6), lower family income (odds ratio 1.7; 95% confidence interval 1.1-2.7), sharing personal hygiene objects (odds ratio 2.0; 95% confidence interval 1.3-3.3), using injected drugs (odds ratio 21.6; 95% confidence interval 10.8-43.0) and crack cocaine (odds ratio 2.8; 95% confidence interval 1.1-6.9) were independently associated with co-infection by hepatitis C virus.

CONCLUSION

These results confirm the risk profile for hepatitis C virus-HIV infection and suggest that sharing personal hygiene objects might explain the transmission of virus C to those not infected by the usual routes, which may be of relevance for developing preventive strategies.

Obstructive sleep apnea and resistant hypertension: a case-control study

BACKGROUND

Obstructive sleep apnea syndrome (OSAS) has been linked to resistant hypertension, but the magnitude of this association and its independence of confounding have not been established.

METHODS

Case patients were 63 patients with resistant hypertension (BP >or= 140/90 mm Hg using at least three BP-lowering drugs, including a diuretic), and control subjects were 63 patients with controlled BP receiving drug treatment. The primary outcome was the frequency of OSAS (apnea-hypopnea index [AHI] >or= 10 episodes per hour) determined with a portable home monitor. The comparison of AHI episodes in patients truly normotensive, truly hypertensive, and in patients with white coat or masked hypertension, based on BP determined at office and by ambulatory BP monitoring (ABPM) was a secondary outcome.

RESULTS

Case patients and control subjects were well matched for confounding factors. OSAS was present in 45 case patients (71%) and in 24 control subjects (38%) [p < 0.001]. In a logistic regression model, OSAS was strongly and independently associated with resistant hypertension (odds ratio, 4.8; 95% confidence interval, 2.0 to 11.7). The AHI of case patients with normal BP in ABPM (white coat hypertension) and control subjects with abnormal BP in ABPM (masked hypertension) was intermediate between the AHI of individuals with normal and abnormal BP measures in both settings (p < 0.001).

CONCLUSIONS

The magnitude and independence of the risk of OSAS for resistant hypertension strengthen the concept that OSAS is a risk factor for resistant hypertension. Comorbid OSAS should be considered in patients with resistant hypertension.

Clustering of risk factors for cardiovascular disease among women in Southern Brazil: a population-based study

The association between clustering of risk factors and self-reported cardiovascular disease among women was investigated in a cross-sectional study using a multistage population-based sample. Participants were interviewed at home about diabetes mellitus, physical activity, and diet pattern. Hypertension was defined as blood pressure > 140/90mmHg or use of anti-hypertensive medication. Cardiovascular disease included self-reported myocardial infarction, heart failure, coronary artery bypass surgery, and stroke. A sample of 1,007 women from Porto Alegre, Southern Brazil, mostly white (73%), 44.8 ± 0.8 years old, and with 9.3 ± 0.3 years of schooling was investigated. Hypertension, diabetes mellitus, obesity, low fruit and vegetable intake, and lack of vigorous or moderate physical activity were clustered into a combination of risk factors, which were independently associated with self-reported cardiovascular disease. The main cluster included hypertension and diabetes, accounting for an independent risk ratio of 8.5 (95%CI: 3.0-24.5). Clustering of cardiovascular risk factors is strongly associated with self-reported cardiovascular disease among women.

The efficacy of the combination of sertraline with buspirone for smoking cessation. A randomized clinical trial in nondepressed smokers

In a double-blind placebo-controlled trial, we evaluated the efficacy of the combination of sertraline and buspirone plus cognitive-behavioral treatment to promote tobacco abstinence in individuals referred to a chemical dependency clinic. Ninety eight individuals 18-65 years of age were randomized to placebo or sertraline 25 mg/day for 2 days, followed by 50 mg from day 3 to 90, and buspirone 5 mg three times a day for 7 days, and 10 mg from day 8 to 90. The rate of continuous abstinence at the 26th week of follow-up, informed by the patient, was 43.5% in the active treatment group and 17.3% in the control group (p = 0.01). The odds ratio for continuous abstinence for the intervention group was 4.74 (95% CI 1.50-14.55) (adjusted for smoker households and number of cognitive sessions). Nicotine withdrawal symptoms were common in both groups (98.7% vs. 95.5% p = 0.37). The combination of sertraline and buspirone with cognitive-behavioral therapy was more effective than placebo and cognitive-behavioral therapy to promote smoking cessation.

Development and validity of a method for the evaluation of printed education material

Objectives

To develop and study the validity of an instrument for evaluation of Printed Education Materials (PEM); to evaluate the use of acceptability indices; to identify possible influences of professional aspects.

Methods

An instrument for PEM evaluation was developed which included tree steps: domain identification, item generation and instrument design. A reading to easy PEM was developed for education of patient with systemic hypertension and its treatment with hydrochlorothiazide. Construct validity was measured based on previously established errors purposively introduced into the PEM, which served as extreme groups. An acceptability index was applied taking into account the rate of professionals who should approve each item. Participants were 10 physicians (9 men) and 5 nurses (all women).

Results

Many professionals identified intentional errors of crude character. Few participants identified errors that needed more careful evaluation, and no one detected the intentional error that required literature analysis. Physicians considered as acceptable 95.8% of the items of the PEM, and nurses 29.2%. The differences between the scoring were statistically significant in 27% of the items. In the overall evaluation, 66.6% were considered as acceptable. The analysis of each item revealed a behavioral pattern for each professional group.

Conclusions

The use of instruments for evaluation of printed education materials is required and may improve the quality of the PEM available for the patients. Not always are the acceptability indices totally correct or represent high quality of information. The professional experience, the practice pattern, and perhaps the gendre of the reviewers may influence their evaluation. An analysis of the PEM by professionals in communication, in drug information, and patients should be carried out to improve the quality of the proposed material.

The efficacy of herbal medicines in clinical models: the case of jambolan

A large proportion of drugs employed in clinical practice come from plants. The development of new medical agents is a lengthy and time-consuming process, with the identification of extracts with putative therapeutic effects, the isolation of active ingredients and pre-clinical studies to investigate their pharmacological profile. We propose a shortcut in this sequence of procedures, testing first if the extracts, in the way they are used by patients, have efficacy in clinical models. On the one hand, this allows to screen plants with higher chances to identify novel drug candidates; this method may result in information with immediate interest for patients who take these traditional preparations, informing them about efficacy, inertia and risks of the product. In this commentary, we describe our own experience applying this approach to investigate the potential antihyperglycemic effect of tea and extracts prepared from leaves of jambolan (Syzygium cumini and Syzygium jambos). The experiments with normal rats, rats with streptozotocin-induced diabetes, normal volunteers and patients with diabetes were all negative in regard to an antihyperglycemic effect of this plant. In view of the pharmacological inertia of jambolan in the clinical model, patients and physicians should not rely on its putative antihyperglycemic effect. This approach may also be applicable to other popular medicines employed in the management of diabetes and other diseases.