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David F Blackburn

Publications and source records attributed to David F Blackburn.

5 recordsLinked to original sources
PubMed2006

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in hypertension due to primary aldosteronism: a case for exclusion.

Aldosterone antagonists are the mainstay of therapy in patients with hypertension due to primary aldosteronism. However, in our experience, these patients are sometimes placed on angiotensin-converting enzyme (ACE) inhibitors in accordance with guidelines applying to the general hypertensive population. We believe this practice is inappropriate because of the inability of ACE inhibitors to lower blood pressure in patients with low renin levels. Furthermore, pleiotropic effects of ACE inhibitors are unlikely to provide significant benefits in the absence of blood pressure reduction. Therefore, ACE inhibitors should be discouraged for the majority of patients with primary aldosteronism, even in the face of renal or cardiac disease.

Angiotensin Receptor Antagonists↗
PubMed2006

Antihypertensive medications and blood sugar: theories and implications.

Increased rates of diabetes have been reported with thiazide diuretics and beta-blockers, but not with angiotensin-converting enzyme inhibitors, angiotensin receptor blockers or calcium channel blockers. These observations are important because significant glycemic effects of drugs may be a source of accelerated cardiovascular risk that is not detectable during restricted clinical trial follow-up periods. The extent to which diabetes is affected by these medications remains unclear, as is the precise mechanism by which diabetes is promoted. However, several plausible theories are presented herein. Although drug-induced diabetes has been a concern for several years, not enough information is available to influence prescribing for the majority of patients. The number one priority should be controlling blood pressure in a timely manner.

Adrenergic beta-Antagonists↗
PubMed2005

Adherence to statins, beta-blockers and angiotensin-converting enzyme inhibitors following a first cardiovascular event: a retrospective cohort study.

BACKGROUND: Population studies of statin adherence are generally restricted to one to two years of follow-up and do not analyze adherence to other drugs. OBJECTIVES: To report long-term adherence rates for statins, angiotensin-converting enzyme (ACE) inhibitors and beta-blockers in patients who recently experienced a first cardiovascular event. METHODS: Linked administrative databases in the province of Saskatchewan were used in this retrospective cohort study. Eligible patients received a new statin prescription within one year of their first cardiovascular event between 1994 and 2001. Adherence to statins, beta-blockers and ACE inhibitors was assessed from the first statin prescription to a subsequent cardiovascular event. RESULTS: Of 1221 eligible patients, the proportion of patients adherent to statin medications dropped to 60.3% at one year and 48.8% at five years. The decline in the proportion of adherent patients was most notable during the first two years (100% to 53.7%). Several factors were associated with statin adherence, including age (P = 0.012), number of physician service days (P = 0.037), chronic disease score (P = 0.032), beta-blocker adherence (P < 0.001) and ACE inhibitor adherence (P < 0.001). Adherence to beta-blockers and ACE inhibitors was very similar to adherence to statin medications at each year of follow-up. CONCLUSIONS: Patients who exhibit optimal adherence over one to two years after their initial cardiovascular event generally remain adherent over subsequent years. Also, adherence to beta-blockers and ACE inhibitors is significantly associated with statin adherence in a subset of patients; however, overall adherence to all three drugs was similarly poor.

Adrenergic beta-Antagonists↗
PubMed2005

Cardiovascular morbidity associated with nonadherence to statin therapy.

STUDY OBJECTIVE: To measure the extent of cardiovascular morbidity associated with nonadherence to 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (statin) therapy. DESIGN: Retrospective cohort study. DATA SOURCE: Linked administrative health databases in Saskatchewan, Canada. PATIENTS: A total of 1221 patients aged 30-70 years who received a new prescription for a statin drug between 1994 and 2001, within 1 year of their first cardiovascular event (i.e., myocardial infarction, unstable angina, ischemic stroke, percutaneous transluminal coronary angioplasty [PTCA], or coronary artery bypass graft [CABG]). MEASUREMENTS AND MAIN RESULTS: Adherence was measured by the fill frequency (number of prescriptions filled during the observation period divided by months of observation). Patients with a fill frequency of 80% or greater were classified as adherent (661 patients); those with a fill frequency of 60% or less were classified as nonadherent (395 patients). The remaining 165 patients who had adherence rates of 61-79% were excluded from the analysis. The primary end point included a composite of myocardial infarction, unstable angina, PTCA, CABG, and death. Among 1056 patients, adherence was not associated with a reduction of the primary end point. However, patients in the adherent group were half as likely to experience a subsequent myocardial infarction as the patients in the nonadherent group (hazard ratio [HR] 0.45, 95% confidence interval [CI] 0.20-0.99, p=0.047). In patients younger than 65 years (both adherent and not), the associated reduction in myocardial infarction was even more profound (HR 0.14, 95% CI 0.04-0.46, p=0.001) and was accompanied by a trend for a lower frequency of unstable angina (HR 0.37, 95% CI 0.13-1.03, p=0.06). In patients 65 years or older (301 patients), adherence was not associated with significant changes in cardiovascular end points. CONCLUSION: A detectable excess of cardiovascular morbidity appears to be associated with nonadherence to statin therapy. Our analysis suggests that many occurrences of myocardial infarction could be prevented with improvements in adherence. Larger studies are necessary to determine the association between adherence and other cardiovascular end points.

Adult↗