Angiotensin Receptor Blockers and the Risk of Cancer: Insights from Clinical Trials and Recent Drug Recalls

Chronic mitochondrial dynamic-targeted therapy alleviates left ventricular dysfunction by reducing multiple programmed cell death in post-myocardial infarction rats

Mitochondrial dysfunction and the activation of multiple programmed cell death (PCD) have been shown to aggravate the severity and mortality associated with the progression of myocardial infarction (MI). Although pharmacological modulation of mitochondrial dynamics, including treatment with the fusion promoter (M1) and the fission inhibitor (Mdivi-1), exerted cardioprotection against several cardiac complications, their roles in the post-MI model have never been investigated. Using a MI rat model instigated by permanent left-anterior descending (LAD) coronary artery occlusion, post-MI rats were randomly assigned to receive one of 4 treatments (n = 10/group): vehicle (DMSO 3%V/V), enalapril (10 mg/kg), Mdivi-1 (1.2 mg/kg) and M1 (2 mg/kg), while a control group of sham operated rats underwent surgery without LAD occlusion (n = 10). After 32-day treatment, cardiac and mitochondrial function, and histopathological morphology were investigated and molecular analysis was performed. Treatment with enalapril, Mdivi-1, and M1 significantly mitigated cardiac pathological remodeling, reduced myocardial injury, and improved left ventricular (LV) function in post-MI rats. Importantly, all interventions also attenuated mitochondrial dynamic imbalance and mitigated activation of apoptosis, necroptosis, and pyroptosis after MI. This investigation demonstrated for the first time that chronic mitochondrial dynamic-targeted therapy mitigated mitochondrial dysfunction and activation of PCD, leading to improved LV function in post-MI rats.

Concentrations of Transition Metal Ions in Rat Lungs after Tobacco Smoke Exposure and Treatment with His-Leu Dipeptide

Tobacco smoking is deleterious to the lungs because it exposes them to many toxic substances. These include transition metal ions, such as cadmium. However, there is a lack of information about the influence of endogenous metal-binding peptides, such as His-Leu (HL), on the lung distribution of transition metals in smokers. To address this, we administered HL subcutaneously to rats exposed to tobacco smoke for six weeks, then we measured the concentrations of transition metal ions in the lungs. We found that exposure to tobacco smoke elevates the concentrations of Cd(II) and Cu(II). Administration of the HL peptide, whose elevation is a consequence of angiotensin receptor blocker anti-hypertension therapy, increases the concentration of Fe in the lungs of rats exposed to smoke. These findings suggest that smoking is a risk factor for patients receiving angiotensin receptor blockers to treat hypertension.

Cancer Risk of Angiotensin II Receptor Blocker Valsartan: A Population-based Study

ABSTRACT

Nitrosamine contamination of generic valsartan was found in 2018. This study aimed to investigate whether long-term use of valsartan increases cancer risk. Patients prescribed valsartan or amlodipine (control group) from 1 January 1, 2003, to June 30, 2010, were identified using the Clinical Data Analysis and Reporting System of the Hong Kong Hospital Authority, a territory-wide database in Hong Kong. Patients previously diagnosed with cancer, prescribed both medications, taking the medication, or followed up for <1 year were excluded. Cancer incidence, adjusted for age, sex, and Charlson Comorbidity Index, was the primary outcome and was estimated using Poisson regression in R version 3.6.1. Among 5023 valsartan users and 3692 amlodipine users, 887 and 740 were diagnosed with cancers during median follow-up periods of 10.97 and 12.12 years, respectively. The adjusted incidence of cancer in valsartan and amlodipine users was 165.29 (95% confidence interval 154.76-175.53) and 180.12 (167.35-193.67) per 10,000 person-years, respectively. The cancer incidence rate ratio of valsartan relative to amlodipine was 0.94 (0.88-1.01). Adjusted incidence rate ratios of valsartan relative to amlodipine were significant for breast cancer (0.63, 0.46-0.86) only. Our findings do not suggest an increase in incidence of cancer with long-term valsartan use. The duration of follow-up of more than 10 years of the study provides the reassurance that an increase in cancer risk is unlikely. Further studies are needed to elucidate the long-term effect of valsartan use on the risk of specific types of cancer.

The Relationship Between Anti-Hypertensive Drugs and Cancer: Anxiety to be Resolved in Urgent

Hypertension is the prevailing independent risk factor for cardiovascular disease worldwide. Anti-hypertensive drugs are the common and effective cure for lowering blood pressure in patients with hypertension. However, some large-scale clinical studies have pointed out that long-term ingestion of some oral anti-hypertensive drugs was associated with risks of incident cancer and the survival time. In contrast, other studies argue that anti-hypertensive drugs are not related to the occurrence of cancer, even as a complementary therapy of tumor treatment. To resolve the dispute, numerous recent mechanistic studies using animal models have tried to find the causal link between cancer and different anti-hypertensive drugs. However, the results were often contradictory. Such uncertainties have taken a toll on hypertensive patients. In this review, we will summarize advances of longitudinal studies in the association between anti-hypertensive drugs and related tumor risks that have helped to move the field forward from associative to causative conclusions, in hope of providing a reference for more rigorous and evidence-based clinical research on the topic to guide the clinical decision making.

Impact of angiotensin receptor blocker product recalls on antihypertensive prescribing in Germany

In Germany, ~8 million patients take angiotensin receptor blockers (ARBs) and 2.25 million of them valsartan. In 2018, contamination of generic ARBs with probable carcinogenic nitrosamines resulted in more than 30 recalls. The impact of such a huge recall has never been explored in Europe. We analyzed the utilization of valsartan, all ARBs, and other alternative antihypertensive drugs in Germany. We used our database of anonymized dispensing data from >80% of community pharmacies at the expense of the statutory health insurance (SHI) funds from January 2017 to December 2019. We analyzed 290.8 million prescriptions, including all oral mono- and fixed-dose combinations of ARBs and plausible alternatives, i.e. ACE inhibitors (ACEi), beta-blockers (BB), and calcium channel blockers (CCB). Utilization was calculated by defined daily doses per 1000 SHI-insured persons per day (DID). Valsartan use decreased substantially after the recalls in July 2018 from 39.0 to 14.2 DID (−64%) in the second quarter of 2019 and to 16.9 DID (−57%) in the fourth quarter of 2019. Simultaneously, the use of alternative ARBs increased from 77.7 DID in the second quarter of 2018 to 121.9 DID (+57%) in the fourth quarter of 2019, mainly due to an increase of candesartan dispensing to 99.8 DID (+73%). There were no changes in the utilization of ACEi, BB, or CCB. The majority of recalled generic valsartan products were replaced by other ARBs, predominantly candesartan, despite documented drug shortages. In contrast to previous safety warnings/recalls, our data do not suggest an under-prescription of antihypertensives during this period.