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Michael H Alderman

Publications and source records attributed to Michael H Alderman.

45 records · Page 3Linked to original sources
PubMed2002

Impact of dietary sodium on cardiovascular disease morbidity and mortality.

Many public health agencies recommend universal restriction of dietary sodium to 100 mmol/L or less per day. This reflects the belief that because sodium restriction reduces blood pressure, it will therefore also reduce cardiovascular disease morbidity and mortality. Although large (100 mmol/L/24 h) reductions in sodium intake do produce a measurable decline in aggregate blood pressure, there is great heterogeneity in individual response, probably reflecting differing genetic, environmental, and behavioral characteristics. Moreover, sodium depletion has multiple other effects including activation of the renin-angiotensin system and the sympathetic nervous system, and increase in insulin resistance. Since the health effect will be the sum of these multiple good and bad effects of sodium reduction, outcome trials are needed to determine the benefit or harm of alteration in sodium intake. Unfortunately, no clinical trial has addressed the question of whether a lower sodium diet would improve or extend life. The best available data derives from six prospective cohort studies. In sum, the scant available observational data do not rule out the possibility of benefit for some and increased risk for others. Considerable experience--most recently the hormone replacement study--underscores the hazards of extrapolating clinical recommendations from observational data alone. In the absence of any evidence from randomized trials of morbidity and mortality outcomes, and in the face of inconsistent observational studies, a universal recommendation for sodium restriction is unwarranted and inconsistent with the principles of evidence-based medicine.

Blood Pressure↗
PubMed2002

Low sodium diet after DASH: has the situation changed? Dietary Approaches to Stop Hypertension.

The Dietary Approaches to Stop Hypertension (DASH) trial adds to the large body of evidence indicating a direct association of dietary sodium with blood pressure, and showing that rigorous reduction of dietary sodium can reduce blood pressure over a 30-day period by statistically significant amounts. DASH, however, neither addressed nor answered whether a reduction of dietary sodium reduces morbidity and mortality. Data linking baseline sodium to mortality and morbidity outcomes are sparse, with only six known studies. Of these, two showed no association, two showed an inverse association, and two showed a direct association only in obese subsets. No studies have examined outcomes after sodium reduction, and no studies have linked sodium to outcomes or even a blood pressure benefit among treated hypertensives. Universal recommendations for sodium reduction or dietary sodium goals should await evidence that such interventions are both safe and effective as measured by morbidity and mortality outcomes.

Blood Pressure↗
PubMed2002

Hypertension guidelines: criteria that might make them more clinically useful.

Cardiovascular disease prevention depends on reduction of risk factors, including hypertension. Guidelines designed to improve management of hypertension are widely available. Their purpose is to assemble the available data from basic biomedical science, epidemiology, and clinical science in an accessible form with which physicians and patients can make reasoned decisions for individual cases. However, guidelines have been neither widely accepted, nor effectively implemented. We recommend a strategy for guideline preparation designed to yield a product more user friendly, accessible, and effective. Guideline recommendations and the evidence used to make them should be based on an explicit grading system. Relevant clinical as well as nonclinical factors must be considered. Moreover, because the goal of antihypertensive therapy is to prevent cardiovascular events, and the likelihood of such events is determined by multifactor or absolute risk assessment, risk, rather than level of blood pressure (BP), should determine the need for therapy. Similarly, the benefit of therapy must be assessed by reduction in cardiovascular disease morbidity and mortality.

Humans↗
PubMed2002

Uric acid and cardiovascular risk.

Uric acid has long been associated with cardiovascular disease. Most epidemiological evidence suggests a significant, graded, independent and specific association between the level of serum uric acid and cardiovascular morbidity and mortality. This is particularly robust among persons at high cardiovascular risk, including those with hypertension, diabetes and congestive heart failure. Although several potential mechanisms have been identified to explain this association, as yet there is no evidence that uric acid bears a causal or reversible relationship to vascular disease.

Animals↗
PubMed2000

Debate: Does it matter how you lower blood pressure?

Whether it matters how pressure is lowered has been debated since antihypertensive drugs proved to prevent cardiovascular events. However, in clinical trials, while the stroke benefit predicted by a given difference in blood pressure was achieved, the results for myocardial infarction were roughly half that expected. This suggested that adverse drug effects of diuretics and beta-blockers might have detracted from their hypotensive effects. Trials with newer antihypertensive classes have revealed superior effects on outcomes associated with converting enzyme inhibitor use, and that alpha-blockers are less cardioprotective than diuretics. These studies establish that simple blood pressure reduction is an inadequate guide to therapy. The challenge now will be to determine the optimal therapy for each hypertensive patient.

Journal Article↗
PubMedDate not supplied

JNC 7: brief summary and critique.

It is the season for guidelines. During the past month, both the European Society of Hypertension/European Society of Cardiology, and the National High Blood Pressure Education Program (NHBPEP) of the National Heart, Lung, and Blood Institute have published updated consensus recommendations for the prevention and treatment of hypertension (2003 European Society of Hypertension-European Society of Cardiology Guidelines for the Management of Arterial Hypertension. J Hypertens 2003; 221:1011-1053; Chobanian AV, Bakris GL, Black HR, Cushman WC, Green LA, Green LA, Izzo JL Jr, Jones DW, et al. The seventh of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. JAMA 2003; 289:2560-2572). These guidelines seek to meet the needs and aspirations of millions of patients, 100 s of thousands of physicians, as well as health policy and governmental authorities. Confronted by incomplete evidence, conflicting interpretations, and strong professional opinion, writing groups must nevertheless produce a written document within a severely constricted timeframe. It is an ambitious and daunting undertaking. What follows is a selective summary and critique of JNC 7. Criticisms are easy, and will be freely made here, based upon the assumption that the authors suggestion that "the responsible physician's judgment is paramount in managing his or her patients" invites dialogue about the document itself. JNC 7 continues a tradition initiated in 1973 and gets high marks for speed and timeliness, having been created and published in 5 months by a writing group of 10 with review by 33 other "hypertension authorities." The writing group revealed potential financial conflicts, widely reviewed current literature, established and followed defined rules of rating evidence, and functioned entirely without commercial support. Simplicity and brevity were important objectives. The Report was presented at a Press Conference timed to coincide with publication in JAMA. A more detailed supporting document will follow, as will a fold-over card bearing the therapeutic algorithm.

Antihypertensive Agents↗
PubMedDate not supplied

Success and predictors of blood pressure control in diverse North American settings: the antihypertensive and lipid-lowering treatment to prevent heart attack trial (ALLHAT).

CONTEXT: Blood pressure control (<140/90 mm Hg) rates for hypertension fall far short of the US national goal of 50% or more. Achievable control rates in varied practice settings and geographic regions and factors that predict improved blood pressure control are not well identified. OBJECTIVE: To determine the success and predictors of blood pressure control in a large hypertension trial involving a multiethnic population in diverse practice settings. DESIGN: The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial is a randomized, double-blind, active-controlled clinical trial with a mean follow-up of 4.9 years. Participant enrollment began in February 1994 and follow-up was completed in March 2002. SETTING: A total of 623 centers in the United States, Canada, and the Caribbean. PARTICIPANTS: A total of 33,357 participants (aged > or =55 years) with hypertension and at least one other coronary heart disease risk factor. INTERVENTIONS: Participants were randomly assigned to receive (double-blind) chlorthalidone, 12.5-25 mg/d (n=15,255), amlodipine 2.5-10 mg/d (n=9048), or lisinopril 10-40 mg/d (n=9054) after other medication was discontinued. Doses were increased within these ranges and additional drugs from other classes were added as needed to achieve blood pressure control (<140/90 mm Hg). MAIN OUTCOME MEASURES: The outcome measures for this report are systolic and diastolic blood pressure, the proportion of participants achieving blood pressure control (<140/90 mm Hg), and the number of drugs required to achieve control in all three groups combined. RESULTS: Mean age was 67 years, 47% were women, 35% black, 36% diabetic; 90% were on antihypertensive drug treatment at entry. At the first of two pre-randomization visits, blood pressure was <140/90 mm Hg in only 27.4% of participants. After 5 years of follow-up, the percent controlled improved to 66%. Systolic blood pressure was <140 mm Hg in 67% of participants, diastolic blood pressure was <90 mm Hg in 92%, the mean number of drugs prescribed was 2.0+/-1.0, and the percent on > or =2 drugs was 63%. Blood pressure control varied by geographic regions, practice settings, and demographic and clinical characteristics of participants. CONCLUSIONS: These data demonstrate that blood pressure may be controlled in two thirds of a multiethnic hypertensive population in diverse practice settings. Systolic blood pressure is more difficult to control than diastolic blood pressure, and at least two antihypertensive medications are required for most patients to achieve blood pressure control. It is likely that the majority of people with hypertension could achieve a blood pressure <140/90 mm Hg with the antihypertensive medications available today.

Aged↗