Cumulative in-trial and post-trial effects of blood pressure and lipid lowering: systematic review and meta-analysis

Fatty liver index and cardiovascular outcomes in never-treated hypertensive patients: a prospective cohort

The prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing rapidly worldwide, affecting 25-30% of the population. Fatty liver index (FLI) is a validated marker of NAFLD and can be used as a screening tool for hepatic steatosis. The purpose of the study was to evaluate the relationship between FLI and the risk of major cardiovascular events in never treated hypertensive patients. We included 903 hypertensive patients without a history of cardiovascular disease (mean age 52.7 ± 11.4 years; men 55%; baseline clinic BP 149.8 ± 15.2/95.5 ± 10.1 mmHg). Participants were prospectively evaluated for a mean follow-up period of 5.2 ± 3.2 years with at least one annual visit. Patients were also categorized into two groups using an FLI of 60 units. The incidence of cardiovascular events during follow-up was 8.5% (n = 77). Patients with FLI < 60 (n = 625) had a better BP control compared to their counterparts with FLI ≥ 60 (n = 278) during follow up (43% vs 33%, p = 0.02). Cox-regression analysis indicated that FLI (Hazard Ratio [HR], 1.05; 95% Confidence Interval [CI], 1.03-1.07, p < 0.001), FLI z-scores (HR, 3.66; 95% CI, 2.22-6.04) and high-risk FLI (HR, 7.5; 95% CI, 3.12-18.04) were independent determinants of the outcome after adjustment for baseline and follow-up variables. Stratification by diabetes mellitus indicated that FLI predicted the outcome to a greater extent in those with than those without diabetes (P-interaction < 0.001). In conclusion, FLI has an independent prognostic value for the incidence of cardiovascular events in newly diagnosed, never-treated hypertensive patients. Therefore, FLI might identify higher-risk patients in the primary prevention of hypertension.

Compounding Benefits of Cholesterol-Lowering Therapy for the Reduction of Major Cardiovascular Events: Systematic Review and Meta-Analysis

BACKGROUND

Mendelian randomization studies use genetic variants as natural experiments to provide evidence about causal relations between modifiable risk factors and disease. Recent Mendelian randomization studies suggest each mmol/L reduction in low-density lipoprotein cholesterol (LDL-C) sustained over a lifetime can reduce the risk of cardiovascular disease by more than half. However, these findings have not been replicated in randomized clinical trials, and the effect of treatment duration on the magnitude of risk reduction remains uncertain. The aim of this article was to evaluate the relationship between lipid-lowering drug exposure time and relative risk reduction of major cardiovascular events in randomized clinical trials.

METHODS

We conducted a systematic review and meta-analysis of randomized clinical trials of statins, ezetimibe, and proprotein convertase subtilisin/kexin type 9 inhibitors that report LDL-C levels and effect sizes for each year of follow-up. The primary end point was major vascular events, defined as the composite of cardiovascular death, myocardial infarction, stroke, and coronary revascularization. Hazard ratios during each year of follow-up were meta-analyzed using random-effects models.

RESULTS

A total of 21 trials with 184 012 patients and an average mean follow-up of 4.4 years were included. Meta-regression showed there was greater relative risk reduction in major vascular events with increasing duration of treatment (P<0.001). For example, each mmol/L LDL-C lowered was associated with a relative risk reduction in major vascular events of 12% (95% CI, 8%-16%) for year 1, 20% (95% CI, 16%-24%) for year 3, 23% (95% CI, 18%-27%) for year 5, and 29% (95% CI, 14%-42%) for year 7.

CONCLUSIONS

The benefits of LDL-C lowering do not seem to be fixed but increase steadily with longer durations of treatment. The results from short-term randomized trials are compatible with the very strong associations between LDL-C and cardiovascular events seen in Mendelian randomization studies.

Lowering cholesterol, blood pressure, or both to prevent cardiovascular events: results of 8.7 years of follow-up of Heart Outcomes Evaluation Prevention (HOPE)-3 study participants

Aims

Rosuvastatin (10 mg per day) compared with placebo reduced major adverse cardiovascular (CV) events by 24% in 12 705 participants at intermediate CV risk after 5.6 years. There was no benefit of blood pressure (BP) lowering treatment in the overall group, but a reduction in events in the third of participants with elevated systolic BP. After cessation of all the trial medications, we examined whether the benefits observed during the active treatment phase were sustained, enhanced, or attenuated.

Methods and results

After the randomized treatment period (5.6 years), participants were invited to participate in 3.1 further years of observation (total 8.7 years). The first co-primary outcome for the entire length of follow-up was the composite of myocardial infarction, stroke, or CV death [major adverse cardiovascular event (MACE)-1], and the second was MACE-1 plus resuscitated cardiac arrest, heart failure, or coronary revascularization (MACE-2). In total, 9326 (78%) of 11 994 surviving Heart Outcomes Prevention Evaluation (HOPE)-3 subjects consented to participate in extended follow-up. During 3.1 years of post-trial observation (total follow-up of 8.7 years), participants originally randomized to rosuvastatin compared with placebo had a 20% additional reduction in MACE-1 [95% confidence interval (CI), 0.64–0.99] and a 17% additional reduction in MACE-2 (95% CI 0.68–1.01). Therefore, over the 8.7 years of follow-up, there was a 21% reduction in MACE-1 (95% CI 0.69–0.90, P = 0.005) and 21% reduction in MACE-2 (95% CI 0.69–0.89, P = 0.002). There was no benefit of BP lowering in the overall study either during the active or post-trial observation period, however, a 24% reduction in MACE-1 was observed over 8.7 years.

Conclusion

The CV benefits of rosuvastatin, and BP lowering in those with elevated systolic BP, compared with placebo continue to accrue for at least 3 years after cessation of randomized treatment in individuals without cardiovascular disease indicating a legacy effect.

Trial Registration Number

NCT00468923

Monotherapy vs combination treatments of different complexity: a meta-analysis of blood pressure lowering randomized outcome trials

BACKGROUND

Use of drug combinations is recommended by hypertension guidelines for most patients because of the greater blood pressure (BP)-lowering effect compared with monotherapy. However, no evidence is available on outcome benefits of treatment strategies based on drug combinations vs. simpler treatment regimens, using data from randomized clinical trials (RCTs). We evaluated drug combination therapies of different complexity.

METHODS

Electronic databases were searched for BP-lowering RCTs that compared combination treatment or monotherapy vs. placebo, no-treatment or less-complex treatment. Combination treatment was considered as follows: background treatment continued during follow-up on top of the trial drug(s) of interest and drug(s) were added to the initial drug(s) of interest in the majority of the patients. Monotherapy was considered whenever pre-randomization treatment was withdrawn or absent and a single drug was administered at randomization. Complexity of treatment indicates the higher averaged number of daily medications used in the eligible RCTs.

RESULTS

We selected 93 trials (290 304 patients; follow-up, 3.9 years). The on-treatment mean number of drugs was 2.10 and 0.99 in the more and less actively treated patients, respectively. Compared with placebo, no-treatment or less-complex treatment, combination treatments of any complexity (mean number of drugs, 1.40 vs. 0.41, 2.32 vs. 0.48, 2.56 vs. 1.62 and 3.14 vs. 2.19) were associated with reduction of all or most fatal and nonfatal outcomes. There was also an increased rate of side effects leading to treatment discontinuation, although in absolute numbers the benefit usually prevailed.

CONCLUSION

These data provide randomized-based trial evidence that antihypertensive combination treatment up to three or more drugs is protective. The net benefit, however, may be attenuated when side effects are considered.

The Legacy Effect in the Prevention of Cardiovascular Disease

The "legacy effect" describes the long-term benefits that may persist for many years after the end of an intervention period, involving different biological processes. The legacy effect in cardiovascular disease (CVD) prevention has been evaluated by a limited number of studies, mostly based on pharmacological interventions, while few manuscripts on dietary interventions have been published. Most of these studies are focused on intensive treatment regimens, whose main goal is to achieve tight control of one or more cardiovascular risk factors. This review aims to summarise the legacy effect-related results obtained in those studies and to determine the existence of this effect in CVD prevention. There is sufficient data to suggest the existence of a legacy effect after intensive intervention on cardiovascular risk factors; however, this effect is not equivalent for all risk factors and could be influenced by patient characteristics, disease duration, and the type of intervention performed. Currently, available evidence suggests that the legacy effect is greater in subjects with moderately-high cardiovascular risk but without CVD, especially in those patients with recent-onset diabetes. However, preventive treatment for CVD should not be discontinued in high-risk subjects, as the level of existing evidence on the legacy effect is low to moderate.

Observational analyses from ADVANCE and ADVANCE-ON

AIMS

To explain, and document, the epidemiological work associated with the action in diabetes and vascular disease: preterax and diamicron-modified release controlled evaluation (ADVANCE) clinical trial.

MATERIALS AND METHODS

ADVANCE was designed as a randomized controlled multicentre factorial trial in high-risk patients with diabetes. The two interventions were blood pressure lowering medications versus placebo, and intensive glucose control versus standard glucose control. Following termination of the trial, an observational study of surviving participants, able to join, was mounted: the ADVANCE - observational study (ADVANCE-ON). Other epidemiological analyses that were undertaken treated the trial as a cohort study, including using biomarkers from the blood samples taken from ADVANCE subjects as risk exposures.

RESULTS

More than 50 publications have reported epidemiological results from ADVANCE. The main results from ADVANCE-ON suggested attenuated benefits of ADVANCE's blood pressure lowering treatment on all-cause and cardiovascular death, but no such long-term benefits for intensive glucose control, although this did give persistent benefit for end-stage renal disease. The other epidemiological studies found, amongst other things, strong effects of NT-terminal pro-B-type natriuretic peptide and high-sensitivity cardiac troponin T on macrovascular events, microvascular events and all-cause death.

CONCLUSIONS

Embedding post-randomization and epidemiological analyses into clinical trials is worthwhile and can be highly productive in advancing scientific knowledge.

Strategies to alter the trajectory of atherosclerotic cardiovascular disease

PURPOSE OF REVIEW

Cardiovascular disease prevention trials of lipid lowering with statins have shown unexpected long-term benefits after the formal randomized treatment stopped. This finding needs further exploration because it raises the possibility that the trajectory of the disease can be modified.

RECENT FINDINGS

Extended follow up data are now available from further major primary prevention studies and from meta-analyses of the legacy effect of statin trials. New outcome studies have been proposed and launched to test the ability of early intervention to slow or regress atherosclerosis.

SUMMARY

Legacy effects are apparent in trials of LDL lowering in hypercholesterolemic and hypertensive patient cohorts. Over follow up periods of decades, both cardiovascular mortality and all-cause mortality are reduced in individuals who received 3 to 5 years of statin therapy. The phenomenon is observed also in studies of intensive glycemic control suggesting that it is possible to impact plaque development with long-term beneficial consequences. Novel strategies for primary prevention are being devised that include the early use of both prolonged-moderate and short-term aggressive LDL lowering.

Lack of a significant legacy effect of baseline blood pressure 'treatment naivety' on all-cause and cardiovascular mortality in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial

OBJECTIVES

To investigate legacy effects at 14-year follow-up of all-cause and cardiovascular disease (CVD) mortality in 'treatment-naive' or 'previous treatment' groups based on blood pressure (BP)-lowering treatment status at baseline.

METHODS

A post-hoc observational study of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial. We excluded participants with a previous history of CVD events. Cox proportional hazard model and 95% confidence interval were used to estimate the effects of treatment naive on mortality outcomes. Moreover, a subgroup analysis by estimated 10-year Framingham risk score was performed.

RESULTS

In multivariable models adjusting for baseline and in-trial characteristics (BP values and number of BP medications as time-dependent variables), there was no statistically significant difference in 5 and 14-year all-cause mortality with a hazard ratio of 0.93 (95% confidence interval 0.80-1.09) and hazard ratio 0.95 (0.88-1.03) and in 5 and 14-year CVD mortality hazard ratio 0.94 (0.72-1.23) and hazard ratio 0.93 (0.80-1.08). In subgroup by absolute CVD risk, no heterogeneity of the association between treatment naive and short-term or long-term all-cause or CVD mortality were found. All comparisons are between the treatment-naive and previous treatment groups.

CONCLUSION

Physicians are concerned about 'legacy effects' of not treating individuals with a BP of 140 mmHg or over and low absolute risk. When treatment intensification was taken into consideration in the primary prevention population in this study, no adverse legacy effect as a result of baseline BP 'treatment naivety' was evident in 14 years of follow-up. The nonsignificant associations were consistent across the CVD risk subgroups. However, the results may be biased due to unobserved residual confounding and therefore should be interpreted with caution.

Legacy effects of statins on cardiovascular and all-cause mortality: a meta-analysis

OBJECTIVES

To assess evidence for 'legacy' (post-trial) effects on cardiovascular disease (CVD) mortality and all-cause mortality among adult participants of placebo-controlled randomised controlled trials (RCTs) of statins.

DESIGN

Meta-analysis of aggregate data.

SETTING/PARTICIPANTS

Placebo-controlled statin RCTS for primary and secondary CVD prevention.

METHODS

Data sources: PubMed, Embase from inception and forward citations of Cholesterol Treatment Trialists' Collaborators RCTs to 16 June 2016.

STUDY SELECTION

Two independent reviewers identified all statin RCT follow-up reports including ≥1000 participants, and cardiovascular and all-cause mortality.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

MAIN OUTCOMES

Post-trial CVD and all-cause mortality.

RESULTS

We included eight trials, with mean post-trial follow-up ranging from 1.6 to 15.1 years, and including 13 781 post-trial deaths (6685 CVD). Direct effects of statins within trials were greater than legacy effects post-trials. The pooled data from all eight studies showed no evidence overall of legacy effects on CVD mortality, but some evidence of legacy effects on all-cause mortality (p=0.01). Exploratory subgroup analysis found possible differences in legacy effect for primary prevention trials compared with secondary prevention trials for both CVD mortality (p=0.15) and all-cause mortality (p=0.02). Pooled post-trial HR for the three primary prevention studies demonstrated possible post-trial legacy effects on CVD mortality (HR=0.87; 95% CI 0.79 to 0.95) and on all-cause mortality (HR=0.90; 95% CI 0.85 to 0.96).

CONCLUSIONS

Possible post-trial statin legacy effects on all-cause mortality appear to be driven by the primary prevention studies. Although these relative benefits were smaller than those observed within the trial, the absolute benefits may be similar for the two time periods. Analysis of individual patient data from follow-up studies after placebo-controlled statin RCTs in lower-risk populations may provide more definitive evidence on whether early treatment of subclinical atherosclerosis is likely to be beneficial.

Vascular legacy beyond blood pressure control: benefits of perindopril/indapamide combination in hypertensive patients with diabetes

OBJECTIVES

Much of the chronic care of patients with type 2 diabetes mellitus and hypertension involves the prevention of diabetic complications. Renin-angiotensin system inhibitors are recommended as first-line therapies because of their nephroprotective properties. Their combination with metabolically neutral diuretics is recommended to reduce blood pressure, morbidity and mortality. Our objective was to review the mechanisms by which the combination of the angiotensin-converting enzyme inhibitor, perindopril, and metabolically neutral thiazide-like diuretic, indapamide, targets the pathways involved in microvascular and macrovascular diabetic complications.

METHODS

For this narrative review, extensive literature searches were performed using PubMed/Medline. Articles published in English describing clinical trials and mechanism of action studies that were relevant to the treatment of patients with perindopril and/or indapamide were included.

RESULTS

Perindopril/indapamide treatment has been shown to reduce blood pressure and to have significant beneficial effects on arterial distensibility, kidney structure and function, and endothelial function. Recent data also suggests that perindopril may reduce the deleterious accumulation of advanced glycation end products in diabetic tissue. In the Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation diabetes trial, perindopril/indapamide treatment significantly reduced the relative risk of microvascular and macrovascular events by 9%, cardiovascular mortality by 18%, and all-cause mortality by 14%. Interestingly, 6 years after the end of the double-blind period, follow-up data showed that the beneficial effects on mortality continued to be significant even though differences in blood pressure and glycated hemoglobin levels had not been significant for several years. Together this data suggests that treatment with perindopril/indapamide has microvascular and macrovascular effects that extend beyond blood pressure lowering and that this treatment might confer a long-lasting beneficial vascular legacy.

CONCLUSION

Moving forward, understanding the pathophysiological bases of the effects that extend beyond those of blood pressure control will help us differentiate between anti-hypertensive choices.