Drug Therapy of Dyslipidemia in the Elderly

Effect of statin treatment on mortality in elderly patients with type 2 diabetes mellitus patients: a retrospective cohort study

BACKGROUND

The effects of statins on the reduction of mortality in individuals aged 75 years or older remain controversial. We conducted this study to investigate whether there is an association between statin therapy and mortality in patients with type 2 diabetes mellitus (T2DM) who are over the age of 75 years.

METHODS

The present study used data from the Staged Diabetes Targeting Management Study, which began in 2005. A total of 518 T2DM patients older than 75 years were included. Cox regression analyses were used to evaluate the association between statins and specific causes of death in patients with T2DM.

RESULTS

After a follow-up period of 6.09 years (interquartile range 3.94-8.81 years), 111 out of 518 patients died. The results of Cox regression analyses showed that there was no significant association between statin use and all-cause mortality (HR 0.75; 95% CI 0.47, 1.19) after adjustment for all potential confounders. Subgroup analysis indicated that statins had no association with the risk of all-cause mortality or deaths caused by ischemic cardiovascular diseases in T2DM patients with or without coronary heart disease.

CONCLUSIONS

Our study found no significant association between all-cause mortality and statin use in T2DM patients over the age of 75 years. More evidence is needed to support the use of statins in the elderly T2DM patients.

Metformin Impedes Oxidation of LDL In Vitro

Metformin is the most commonly prescribed glucose-lowering drug for the treatment of type 2 diabetes. The aim of this study was to investigate whether metformin is capable of impeding the oxidation of LDL, a crucial step in the development of endothelial dysfunction and atherosclerosis. LDL was oxidized by addition of CuCl2 in the presence of increasing concentrations of metformin. The extent of LDL oxidation was assessed by measuring lipid hydroperoxide and malondialdehyde concentrations, relative electrophoretic mobilities, and oxidation-specific immune epitopes. Cytotoxicity of oxLDL in the vascular endothelial cell line EA.hy926 was assessed using the alamarBlue viability test. Quantum chemical calculations were performed to determine free energies of reactions between metformin and radicals typical for lipid oxidation. Metformin concentration-dependently impeded the formation of lipid hydroperoxides, malondialdehyde, and oxidation-specific immune epitopes when oxidation of LDL was initiated by addition of Cu2+. The cytotoxicity of oxLDL was reduced when it was obtained under increasing concentrations of metformin. The quantum chemical calculations revealed that only the reaction of metformin with hydroxyl radicals is exergonic, whereas the reactions with hydroperoxyl radicals or superoxide radical anions are endergonic. Metformin, beside its glucose-lowering effect, might be a suitable agent to impede the development of atherosclerosis and associated CVD. This is due to its capability to impede LDL oxidation, most likely by scavenging hydroxyl radicals.

Potentially Inappropriate Medications Use among Older Adults with Dyslipidaemia

BACKGROUND

Since older patients with dyslipidemia frequently receive many prescriptions, medication errors are typical and expected in this population. This risk has increased by using potentially inappropriate medications. The 2019 Beers criteria were used in this study to investigate potentially inappropriate medication use among older individuals with dyslipidemia.

METHODS

A cross-sectional retrospective analysis used data from electronic medical records from an ambulatory-care environment. Patients with dyslipidemia who were older adults (>65 years old) were included. To describe and find potential determinants of potentially inappropriate medication usage, descriptive statistics and logistic regression were employed.

RESULTS

This study included 2209 older adults (age ≥ 65) with dyslipidemia. The mean age was 72.1 ± 6.0 years, and the majority of the study sample had hypertension (83.7%) and diabetes (61.7%), and around 80.0% were using polypharmacy. The prevalence of potentially inappropriate medications to be avoided among older adults with dyslipidemia was 48.6%. A high risk of potentially inappropriate medication usage was found in older patients with dyslipidemia who had polypharmacy and comorbid diabetes, ischemic heart disease, and anxiety.

CONCLUSIONS

This study showed that the number of medications prescribed and the presence of concurrent chronic health conditions are important indicators of the risk of potentially inappropriate medications in ambulatory older patients with dyslipidemia.

Cholesterol metabolism in aging simultaneously altered in liver and nervous system

In humans, aging, triggers increased plasma concentrations of triglycerides, cholesterol, low-density lipoproteins and lower capacity of high-density lipoproteins to remove cellular cholesterol. Studies in rodents showed that aging led to cholesterol accumulation in the liver and decrease in the brain with reduced cholesterol synthesis and increased levels of cholesterol 24-hydroxylase, an enzyme responsible for removing cholesterol from the brain. Liver diseases are also related to brain aging, inducing changes in cholesterol metabolism in the brain and liver of rats. It has been suggested that late onset Alzheimer's disease is associated with metabolic syndrome. Non-alcoholic fatty liver is associated with lower total brain volume in the Framingham Heart Study offspring cohort study. Furthermore, disorders of cholesterol homeostasis in the adult brain are associated with neurological diseases such as Niemann-Pick, Alzheimer, Parkinson, Huntington and epilepsy. Apolipoprotein E (apoE) is important in transporting cholesterol from astrocytes to neurons in the etiology of sporadic Alzheimer's disease, an aging-related dementia. Desmosterol and 24S-hydroxycholesterol are reduced in ApoE KO hypercholesterolemic mice. ApoE KO mice have synaptic loss, cognitive dysfunction, and elevated plasma lipid levels that can affect brain function. In contrast to cholesterol itself, there is a continuous uptake of 27- hydroxycholesterol in the brain as it crosses the blood-brain barrier and this flow can be an important link between intra- and extracerebral cholesterol homeostasis. Not surprisingly, changes in cholesterol metabolism occur simultaneously in the liver and nervous tissues and may be considered possible biomarkers of the liver and nervous system aging.

Features and implications of higher systolic central than peripheral blood pressure in patients at very high risk of atherosclerotic cardiovascular disease

Peripheral blood pressure (PBP) is usually higher than central blood pressure (CBP) due to pulse amplification; however, it is not well understood why cuff-measured PBP can be lower than CBP estimated by the late systolic pressure of radial pulse waves. We explored the implications of systolic PBP-CBP (P-CBP) differences for cardiovascular (CV) prognosis. In total, 335 patients at very high risk of atherosclerotic cardiovascular disease (ASCVD) underwent automated applanation tonometry and brachial-ankle pulse wave velocity (baPWV), and they were classified into groups according to positive or negative systolic P-CBP differences. Between-group characteristics and clinical outcomes (the composite of coronary revascularization, stroke, heart failure hospitalization, and CV death) were evaluated. Patients with negative differences had significantly higher frequency of hypertension, coronary artery disease, higher ASCVD risk burden, and elevated N-terminal pro b-type natriuretic peptide. They had higher left atrial volume index (LAVI) and lower systolic mitral septal tissue velocity (TVI-s') than those with a positive difference. These patients showed higher systolic PBP and CBP, and a higher baPWV. Multivariable analysis indicated that TVI-s', LAVI, and ASCVD risk burden were independent determinants of such systolic P-CBP differences. During a median follow-up of 12.6 months, clinical outcomes were significantly related to a negative difference (11.5% vs. 3.4%, p = 0.014), and a systolic P-CBP difference ≤ -8 mmHg was associated with a threefold higher likelihood of poor prognosis. In patients at very high risk of ASCVD, systolic P-CBP difference was associated with cardiac dysfunction and ASCVD risk burden, allowing further risk stratification.

Effect of onion on blood lipid profile: A meta-analysis of randomized controlled trials

BACKGROUND

Studies indicate that onion supplementation may be effective in the treatment of dyslipidemia; however, the results remain controversial. This meta-analysis was conducted to evaluate potential benefits of onion on lipid profile.

METHODS

Up to 12 October 2020, PubMed, Cochrane Library, Web of Science, and Scopus were searched for randomized controlled trials evaluating the effects of onion on lipid profile. Mean differences (MD) and 95% confidence intervals (CI) were calculated. Meta-analysis was conducted using the fixed-effects model.

RESULTS

Ten trials with 446 participants in total were included in the meta-analysis. The pooled findings of 10 studies suggested that onion supplementation significantly improved high-density lipoprotein cholesterol (HDL) (MD: 2.29 mg/dl; 95% CI: 0.87, 3.72; I 2 = 0%) and low-density lipoprotein cholesterol (LDL) (MD: -6.64 mg/dl; 95% CI: -10.91, -2.36; I 2 = 32%),while onion supplementation did not significantly lower triglycerides (TG) (MD: -6.55 mg/dl; 95% CI: -15.64, 2.53; I 2 = 45%). Analysis of nine trials showed a significant reduction in total cholesterol (TC) (MD: -5.39 mg/dl; 95% CI: -10.68, -0.09; I 2 = 49%) in patients with onion supplementation compared to the control group.

CONCLUSION

In summary, supplementation of onion was beneficial to control dyslipidemia, including improving levels of HDL, LDL, and TC, but could not reduce TG level. The therapeutic benefits of onion for dyslipidemia need to be treated with caution considering that some of the results are not robust.

An update on PCSK9 inhibitors- pharmacokinetics, drug interactions, and toxicity

INTRODUCTION

While atherosclerotic cardiovascular disease is affecting growing numbers of patients, lipid-lowering therapies have been continuously improving to achieve prevention of cardiovascular events. Thus, the appearance of a novel therapeutic class, PCSK9 inhibitors, has raised both high expectations as well as concern over possible adverse effects.

AREAS COVERED

This current review aims to analyze adverse events of special interest linked to PCSK9 inhibitors and give recommendations regarding further conduct when dealing with patients on this therapy. The most stringent adverse effect, neurocognitive impairment has been investigated in several studies, concluding that PCSK9 inhibitors neither improved nor worsened cognitive function. While new onset diabetes mellitus has also been a cause of concern due to its possible association with lipid lowering therapies, studies conducted so far have dispelled this possibility by showing that PCSK9 inhibitors do not increase this risk. Also, statin-associated muscle symptoms have not been proven to arise after the use of PCSK9 inhibitors, even in statin-intolerant patients.

EXPERT OPINION

In conclusion, it can be safely stated that so far, no compelling evidence links PCSK9 inhibitors to these adverse events; however, long-term trials are always welcome to further assess potential adverse effects.

Review of the Protective Effects of Statins on Cognition

Elevated cholesterol is a major risk factor in the development of cardiovascular disease. Statins have proven to be effective in lowering low-density lipoprotein cholesterol as well as the incidence of cardiovascular events. As a result, statins are widely prescribed in the United States, with an estimated 35 million patients on statins. Many of these patients are older than age 65 and suffer from various comorbidities, including mild to severe cognitive impairment. Early studies looking at the effects of statins on cognition have shown that statin use may lead to mild reversible cognitive decline, although long-term studies have shown inconclusive findings. In recent years, studies have shown that the use of statins in certain groups of patients may lead to a reduction in the rate of cognitive decline. One hypothesis for this finding is that statin use can reduce the risk of cerebrovascular disease which may, in turn, reduce the risk of mild cognitive decline and dementia. With numerous patients currently prescribed statins and the likelihood that more patients will be prescribed the medication in the coming years, it is important to review the current literature to determine the association between statin use and cognitive decline, as well as determine how statins may be beneficial in preventing cognitive decline.

Statins and Higher Diabetes Mellitus Risk: Incidence, Proposed Mechanisms, and Clinical Implications

3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors are ubiquitously prescribed for cardiovascular disease (CVD) prevention and treatment. However, the use of statins has been linked to the development of new-onset diabetes mellitus (NODM), which could possibly increase future CVD risk. This phenomenon necessitates a clear discussion of the possible etiologies of this relationship and its broader clinical consequences. We discuss the reported incidence of NODM in statin users through a rigorous review of data from metaanalyses of randomized control trials examining this association. We also highlight the various possible mechanisms responsible for the development of statin-induced diabetes mellitus. Finally, we examine the clinical implications of this effect on future CVD risk and identify specific patient factors that can be used for risk-stratification strategies. Data from 14 randomized control trials metaanalyses suggest a 9-33% higher risk of NODM with statin use. Several cellular, molecular, and genetic mechanisms, as well as lifestyle habits, have been identified as potential underlying factors responsible for this elevated risk. The principle mode of the diabetogenic action of statins is still unclear, though it is likely the result of a complex interplay of pancreatic and extrapancreatic effects. It is understood that patient populations with a greater predisposition to diabetes mellitus, and those with thicker epicardial adiposity are more at risk for the development of statin-induced NODM. Despite these observations, robust data from a variety of investigations suggest that the CVD preventative benefits of statin treatment significantly outweigh the risks associated with the development of NODM. Nevertheless, further study must better identify the causative mechanisms involved in this process, its natural history, and the unique factors that will help clinicians risk stratify and appropriately monitor patients on statin therapy.

Association between Statins Prescribed for Primary and Secondary Prevention and Major Adverse Cardiac Events among Older Adults with Frailty: A Systematic Review

BACKGROUND

Statins reduce the risk of major adverse cardiovascular events (MACE), however their clinical benefit for primary and secondary prevention among older adults with frailty is uncertain. This systematic review investigates whether statins prescribed for primary and secondary prevention are associated with reduced MACE among adults aged ≥ 65 years with frailty.

METHODS

We conducted a systematic review of studies published between 1 January 1952 and 1 January 2019 in the MEDLINE, EMBASE, Scopus, Web of Science, Cochrane Library and International Pharmaceutical Abstracts databases. Studies that investigated the effect of statins on MACE among adults ≥ 65 years of age with a validated frailty assessment were included. Data were extracted from the papers as per a prepublished protocol, PROSPERO: CRD42019127486. Risk of bias was assessed using the Cochrane Risk of Bias in Non-Randomised Studies of Interventions tool.

RESULTS

Six cohort studies fulfilled the inclusion criteria; there were no randomised clinical trials. Among studies evaluating the association between statins for primary and secondary prevention and mortality, one study found statins were associated with reduced mortality (hazard ratio [HR] 0.58, 95% confidence interval [CI] 0.37-0.93), while another study found they were not (HR 0.81, 95% CI 0.61-1.08). Furthermore, one study of statins used for secondary prevention found they were associated with reduced mortality (HR 0.28, 95% CI 0.21-0.39). No studies investigated the effect of statins for primary prevention or the effect of statins on the frequency of MACE.

CONCLUSION

This review identified only observational evidence that among older people with frailty, statins are associated with reduced mortality when prescribed for secondary prevention, and an absence of evidence evaluating statin therapy for primary prevention. Randomised trial data are needed to better inform the use of statins among older adults living with frailty.

Factors Associated with Reinitiation of Statin Treatment in Older Patients with Peripheral Arterial Disease

BACKGROUND

Long-term persistence represents a basic precondition of successful statin treatment in patients with peripheral arterial disease (PAD).

OBJECTIVES

The aims of our study were evaluation of reinitiation in older PAD patients who were non-persistent with statin treatment, and identification of patient-related characteristics associated with the patient's probability of reinitiation.

METHODS

Our study cohort included 2977 older patients (≥ 65 years) who were non-persistent with statin treatment in whom PAD was newly diagnosed in 2012. Reinitiation was defined as the first statin prescription recorded after discontinuation. To analyze factors associated with the patient´s probability of reinitiation, Cox regression with time-dependent covariates was applied.

RESULTS

After post-discontinuation follow-up of a mean of 27 months, reinitiation of statin treatment was recorded for 1244 (41.8%) patients. Increasing age, Parkinson's disease, being a new statin user (patient in whom statin treatment was initiated in association with PAD diagnosis), general practitioner as the index prescriber who prescribed a statin for the first time after diagnosis of PAD, coadministration of loop diuretics, and longer persistence before discontinuation decreased the patient's likelihood of reinitiation, whereas myocardial infarction during non-persistence, high-intensity statin treatment, and increasing number of medications increased the patient's probability of reinitiation.

CONCLUSIONS

In patients with characteristics associated with a lower probability of reinitiation, more concentrated outreach and further evaluation of these groups to identify interventions that might be helpful to encourage reinitiation are needed.

Patient-Associated Characteristics Influencing the Risk for Non-Persistence with Statins in Older Patients with Peripheral Arterial Disease

BACKGROUND AND OBJECTIVES

Secondary prevention of peripheral arterial disease includes administration of statins regardless of the patient's serum cholesterol level. Our study aimed to identify patient-associated risk factors for statin non-persistence and comparison of the explanatory power of models based on clusters of patient-associated characteristics.

METHODS

Our study cohort (n = 8330) was assembled from the database of the largest health insurance provider in the Slovak Republic. Statin users aged ≥ 65 years in whom peripheral arterial disease was diagnosed during 2012 were included. Patients were followed for 5 years; those with a treatment gap period of at least 6 months without statin prescription were classified as "non-persistent". The risk factors for non-persistence were identified within six models (sociodemographic, cardiovascular events, comorbid conditions, statin-related characteristics, cardiovascular co-medication and full model) using Cox regression. The explanatory power of models was assessed using Harrell's C-index.

RESULTS

At the end of the follow-up, 35.7% of patients were found to be non-persistent. The full model had the highest explanatory power (C = 0.632). Female sex, atorvastatin and rosuvastatin as initially administered statins, being a new statin user and an increasing co-payment were associated with an increased risk for non-persistence. Increasing age, history of ischaemic stroke, diabetes mellitus, general practitioner as index prescriber, increasing overall number of medications and co-administration of certain cardiovascular co-medications were associated with a lower likelihood for non-persistence.

CONCLUSIONS

Patients identified as high risk for non-persistence require special attention aimed at the improvement of their persistence with statin treatment.

Statins and the potential for higher diabetes mellitus risk

Introduction: 3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) are widely used for cardiovascular disease (CVD) prevention. Long-term use of statins has been linked to the development of diabetes mellitus (DM) which increases CVD risk. Areas covered: We discussed the reported incidence of DM in statin users, various possible mechanisms responsible for the development of DM and the clinical implications of this association on CVD risk. Relevant supporting literature was identified using MEDLINE/EMBASE search. Expert opinion: Data from available RCTs and observational studies suggest a 10-45% higher risk of new-onset DM with statin use compared to nonusers. Several cellular, molecular, and genetic mechanisms, and lifestyle changes have been studied and discussed as potential underlying mechanisms responsible for this elevated DM risk with statin therapy. The mode of the diabetogenic action of statins is still unclear and an interplay of pancreatic and peripheral effects in the pathogenesis of DM is a possibility. Despite these observations, the CVD preventative benefit of statin treatment outweighs the CVD risk associated with of development of new DM. There is a need for further research to identify the exact mechanisms involved so as to specifically target causative factors and individualize treatment.

Keep recycling going: New approaches to reduce LDL-C

Hypercholesterolemia represents a leading cause in the development of atherosclerotic plaques, increasing the risk for ACVS. It actually counts as a major cause of cardiovascular disease etiopathogenesis. The causes of hypercholesterolemia are multifactorial, spanning from genetic constitution, age, sex, to sedentary lifestyle and diets rich in sugars and lipids. Although dietary restriction in saturated fats, increased exercise, and other modification in lifestyle represent a first-line approach to treat very initial stages in hypercholesterolemia, most patients will require the addition of pharmacological agents. Pharmacological approaches include inhibition of cholesterol synthesis, decreased fat absorption from the GI tract, and increased degradation of FA. These strategies present a series of side effects, low therapeutic efficiency in some patients, and reduced tolerability. One of the major goals in treatment for hypercholesterolemia is to decrease the levels of low density lipoproteins (LDL), while maintaining those of high density lipoproteins (HDL). LDL particles contain about 80% of lipids, most of it cholesterol and cholesteryl esters, and 20% of the ApoB-100 protein. LDL carries cholesterol to the tissues, to be incorporated to biological membranes, or to be transformed to steroids. Excess of LDL translates into increased levels of circulating cholesterol particles and accumulation in certain tissues, especially vascular tissue, initiating a fatty streak, which may evolve to an atheroma, causing a series of cardiovascular problems, including impaired circulation, high blood pressure, increased cardiac workload, and coronary artery disease. It is essential to prevent LDL accumulation into the bloodstream to avoid the formation of these fatty streaks and the initiation of a cascade that will lead to the development of atherosclerosis. In healthy individuals. Under physiological conditions, LDL is effectively removed from circulation through receptor-mediated endocytosis. LDL clearance involves binding to its receptor, LDLR, which enables the internalization of the LDL particle and drives its degradation in lysosomes. Once the LDL particle is degraded, the free receptor recycles to the plasma membrane, and captures new LDL particles. Adequate levels of LDLR are essential to remove the excess of cholesterol-laden LDL. Proprotein convertase, subtilysin kexin type 9 (PCSK-9), expressed in liver and intestine, binds to LDLR, and internalized. Once inside the cell, PCSK-9 catalyzes the proteolysis of LDLR, preventing its recycling to the cell surface, and effectively decreasing the number of LDLR, notoriously decreasing the ability to clear LDL from circulation. Levels of PCSK-9 varies with age, gender, and levels of insulin, glucose, and triglycerides. Loss-of-function mutations in PCSK-9 gene invariably translates into lower levels of LDL, and decreased risk of developing coronary artery disease. Conversely, increased activity or expression of this enzyme leads to hypercholesterolemia. Inhibition of PCSK9 has proven to be successful in decreasing LDL levels and risk of the development of hypercholesterolemia with its associated higher risk for ASCVD. Patient with gain-of-function mutations in the PCSK9 undoubtedly benefit from therapies based on PCSK-9 inhibitors. However, millions of patients show statin intolerance, or cannot be efficiently controlled by statins alone- the most prevalent therapy for hypeprcholesterolemia. This commentary will evaluate the possibilities, caveats and future directions in the treatment of hypercholesterolemia, and therapies with combination of drugs.