A Review of the Use of Angiotensin Receptor Blockers for the Prevention of Cardiovascular Events in Patients with Essential Hypertension Without Compelling Indications

Safety and cardiovascular effectiveness of olmesartan in combination therapy for advanced hypertension: an electronic health record-based cohort study

OBJECTIVE

Compared with placebo, olmesartan has been linked to numerical imbalances in cardiovascular mortality. There is a paucity of contemporary real-world evidence on this agent for different study populations. This study investigated the clinical outcomes of olmesartan and other antihypertensives in patients with advanced hypertension.

METHODS

This multicenter retrospective study used data from the Korea University Medical Center database, built from electronic health records. Patients prescribed at least two antihypertensive medications as a combined therapy were followed-up for 3 years. The primary outcome was a composite of all-cause mortality, myocardial infarction (MI), stroke, and hospitalization for heart failure. Adjusted outcomes were compared using propensity score (PS) matching.

RESULTS

Among 24 806 patients, 4050 (16.3%) were olmesartan users between January 2017 and December 2018. The average patient age was 64 years, 45% were women, and 41% had diabetes. Olmesartan users were younger and less likely to have diabetes mellitus or chronic kidney disease. In PS-matched cohort, the 3-year cumulative incidences of the primary outcome were similar between the two groups ( P  = 0.91). The cumulative incidence of MI at 3 years was 1.4% in olmesartan users (4.8 per 1000 person-years) and 1.5% in active comparators (5.2 per 1000 person-years; P  = 0.74). Olmesartan also showed similar safety profiles, including acute kidney injury and newly started dialysis.

CONCLUSIONS

In real-world practice, olmesartan use in combination therapy resulted in similar cardiovascular outcomes when compared with those of active comparators, and our findings did not show any conclusive evidence that olmesartan is harmful in patients with hypertension.

Acetylsalicylic Acid Daily vs Acetylsalicylic Acid Every 3 Days in Healthy Volunteers: Effect on Platelet Aggregation, Gastric Mucosa, and Prostaglandin E2 Synthesis

Substantial platelet inhibition was observed 3 days after a single administration of acetylsalicylic acid 81 mg to healthy volunteers. Here we investigate prostaglandin E2 (PGE2 ) antrum concentrations and gastrointestinal symptoms in two treatment groups: one receiving losartan and acetylsalicylic acid every day and the other receiving losartan every day and acetylsalicylic acid every 3 days. Twenty-eight healthy volunteers from both sexes received either 50 mg losartan and acetylsalicylic acid 81 mg daily or 50 mg losartan and acetylsalicylic acid 81 every 3 days with placebo on the other days. Therapy was delivered for 30 days for both groups. Gastric endoscopy was performed before and after treatment period. Biopsies were collected for PGE2 quantification. Platelet function tests were carried out before and during treatment and TXB2 release on platelet rich plasma was measured. The every 3 day low-dose acetylsalicylic acid regimen produced complete inhibition of platelet aggregation compared to the daily treatment. Thromboxane B2 release was substantially abolished for both groups during treatment. There was no significant difference on the endoscopic score of both treatment groups after the 30-day treatment (P = .215). There was over 50% suppression of antrum PGE2 content on volunteers receiving acetylsalicylic acid daily (P = .0016), while for the every 3 day dose regimen there was no significant difference between pre and post-treatment antrum PGE2 dosages (P = .4193). Since PGE2 is involved in gastric healing, we understand that this new approach could be safer and as efficient as the standard daily therapy on a long-term basis.

Comparative Effectiveness of Olmesartan and Other Angiotensin Receptor Blockers in Diabetes Mellitus

Olmesartan has been linked with increased risk of cardiovascular mortality and sprue-like enteropathy. We compared outcomes between olmesartan and other angiotensin receptor blockers in a large clinical registry of patients with diabetes mellitus. A retrospective cohort analysis using nationwide US-integrated insurance and laboratory claims was performed in 45 185 incident diabetic angiotensin receptor blocker users, including 10 370 (23%) olmesartan users. Hazard ratios were computed using time-dependant Cox models adjusted for sociodemographic characteristics, comorbidities, laboratory data, drug use, healthcare utilization, and the propensity to receive olmesartan. Blood pressure data were unavailable. Subjects were followed up for 116 721 patient-years. The primary end point was all-cause hospitalization or all-cause mortality and occurred in 10 915 (24%) patients. Average age was 54.3±9.6 years, 52% were men, 17% had cardiovascular disease, and 10% chronic kidney disease. Compared with other angiotensin receptor blockers, the adjusted hazard for olmesartan was 0.99 (95% confidence interval, 0.94–1.05) for all-cause hospitalization and mortality; 0.90 (0.62–1.30) for all-cause mortality; 0.99 (0.94–1.05) for all-cause hospital admission; 0.88 (0.78–1.00) for cardiovascular disease–related admission, and 1.09 (0.98–1.20) for gastrointestinal disease–related hospitalization in the overall cohort. Olmesartan use was associated with an adjusted hazard for the primary outcome of 1.11 (0.99–1.24) in subjects with history of cardiovascular disease and 1.21 (1.04–1.41) in subjects with chronic kidney disease. In conclusion, there is no robust signal for harm with olmesartan use. Risk may be increased in kidney disease; thus, given the widespread availability of alternate agents, olmesartan should be used with caution in this subgroup pending further study.