Gauging the impact of statins using number needed to treat

Estimated 5-Year Number Needed to Treat to Prevent Cardiovascular Death or Heart Failure Hospitalization With Angiotensin Receptor-Neprilysin Inhibition vs Standard Therapy for Patients With Heart Failure With Reduced Ejection Fraction: An Analysis of Data From the PARADIGM-HF Trial

Importance

The addition of receptor-neprilysin inhibition to standard therapy, including a renin-angiotensin system blocker, has been demonstrated to improve outcomes in patients with heart failure with reduced ejection fraction (HFrEF) compared with standard therapy alone. The long-term absolute risk reduction from angiotensin receptor neprilysin inhibitor (ARNI) therapy, and whether it merits widespread use among diverse subpopulations, has not been well described.

Objective

To calculate estimated 5-year number needed to treat (NNT) values overall and for different subpopulations for the Prospective Comparison of ARNI with Angiotensin-Converting Enzyme Inhibitor (ACEI) to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) cohort.

Design, Setting, and Participants

Overall and subpopulation 5-year NNT values were estimated for different end points using data from PARADIGM-HF, a double-blind, randomized trial of sacubitril-valsartan vs enalapril. This multicenter, international study included 8399 men and women with HFrEF (ejection fraction, ≤40%). The study began in December 2009 and ended in March 2014. Analyses began in March 2018.

Interventions

Random assignment to sacubitril-valsartan or enalapril.

Main Outcomes and Measures

Cardiovascular death or HF hospitalization, cardiovascular death, and all-cause mortality.

Results

The final cohort of 8399 individuals included 1832 women (21.8%) and 5544 white individuals (66.0%), with a mean (SD) age of 63.8 (11.4) years. The 5-year estimated NNT for the primary outcome of cardiovascular death or HF hospitalization with ARNI therapy incremental to ACEI therapy in the overall cohort was 14. The 5-year estimated NNT values were calculated for different clinically relevant subpopulations and ranged from 12 to 19. The 5-year estimated NNT for all-cause mortality in the overall cohort with ARNI incremental to ACEI was 21, with values ranging from 16 to 31 among different subgroups. Compared with imputed placebo, the 5-year estimated NNT for all-cause mortality with ARNI was 11. The 5-year estimated NNT values were also calculated for other HFrEF therapies compared with controls from landmark trials for all-cause mortality and were found to be 18 for ACEI, 24 for angiotensin receptor blockers, 8 for β-blockers, 15 for mineralocorticoid antagonists, 14 for implantable cardioverter defibrillator, and 14 for cardiac resynchronization therapy.

Conclusions and Relevance

The 5-year estimated NNT with ARNI therapy incremental to ACEI therapy overall and for clinically relevant subpopulations of patients with HFrEF are comparable with those for well-established HF therapeutics. These data further support guideline recommendations for use of ARNI therapy among eligible patients with HFrEF.

Statin Discontinuation, Reinitiation, and Persistence Patterns Among Medicare Beneficiaries After Myocardial Infarction: A Cohort Study

BACKGROUND

Although the benefits of statins accrue over time, treatment discontinuation is common. Examining the patterns of statin discontinuation, reinitiation, and persistence after reinitiation among Medicare beneficiaries after hospital discharge for a myocardial infarction may help increase statin use in high-risk patients.

METHODS AND RESULTS

Medicare beneficiaries with a statin fill claim within 30 days after hospital discharge for myocardial infarction in 2007 to 2012 (n=158 795) were followed for 182 days post-discharge to identify discontinuation, defined as 60 continuous days without statins available. Reinitiation, defined by a statin fill, was identified in the 365 days post-discontinuation. High persistence was defined as proportion of days covered ≥80% with ≥1 day of statin supply 182 days after reinitiation. Follow-up ended on December 31, 2014. In the 182 days after myocardial infarction hospital discharge, 15.4% of beneficiaries discontinued statins. Of this group, 53.7% reinitiated statins. On reinitiation, 27.1% changed statin type, 6.9% up-titrated intensity, 14.4% down-titrated intensity, and 66.0% had the same statin and intensity. In the 182 days after reinitiation, 45.8% had high persistence. Moderate- and high- versus low-intensity statins were associated with a lower risk for statin discontinuation (moderate intensity: relative risk [RR], 0.93; 95% confidence interval [CI], 0.89-0.96; high-intensity: RR, 0.95; 95% CI, 0.91-0.99). High persistence was less common after reinitiating high- versus low-intensity statins (RR, 0.80; 95% CI, 0.75-0.86), but no association was present for those reinitiating a moderate- versus low-intensity statin (RR, 0.95; 95% CI, 0.90-1.01). Down-titrating versus reinitiating the same statin intensity (RR, 1.10; 95% CI, 1.05-1.16) and reinitiating a different versus the same statin (RR, 1.10; 95% CI, 1.06-1.14) were associated with high persistence after treatment reinitiation.

CONCLUSIONS

Although many people who discontinue a statin reinitiate treatment, statin persistence after reinitiation was low. Reinitiating therapy with moderate-intensity statins, down-titration, and using a different statin may promote persistence.

Healthcare Utilization and Statin Re-Initiation Among Medicare Beneficiaries With a History of Myocardial Infarction

Background

Contact with the healthcare system represents an opportunity for individuals who discontinue statins to re‐initiate treatment. To help identify opportunities for healthcare providers to emphasize the risk‐lowering benefits accrued through restarting statins, we determined the types of healthcare utilization associated with statin re‐initiation among patients with history of a myocardial infarction.

Methods and Results

Medicare beneficiaries with a statin pharmacy fill claim within 30 days of hospital discharge for a myocardial infarction in 2007 to 2012 (n=158 795) were followed for 182 days postdischarge to identify treatment discontinuation, defined as 60 continuous days without statins (n=24 461). Re‐initiation was defined as a statin fill within 365 days of the discontinuation date (n=13 136). Using a case‐crossover study design and each beneficiary as their own control, healthcare utilization during 0 to 14 days before statin re‐initiation (case period) was compared with healthcare utilization 30 to 44 days before statin re‐initiation (control period). The mean age of beneficiaries was 75.4 years; 52.8% were women and 81.9% were white. For routine healthcare utilization, the odds ratio (95% confidence interval) for statin re‐initiation associated with lipid panel testing was 2.65 (1.93–3.65), outpatient primary care was 1.31 (1.23–1.40), and outpatient cardiologist care was 1.38 (1.28–1.50). For acute healthcare utilization, the odds ratio (95% confidence interval) for statin re‐initiation associated with emergency department visits was 1.77 (1.31–2.40), coronary heart disease (CHD) hospitalizations was 3.16 (2.41–4.14) and non–coronary heart disease hospitalizations was 1.73 (1.49–2.01).

Conclusions

The weaker association of routine versus acute healthcare utilization with statin re‐initiation suggests missed opportunities to reinforce the importance of statin therapy for secondary prevention.

Early, intensive statin treatment reduces 'hard' cardiovascular outcomes after acute coronary syndrome

Background Early, intensive statin treatment is the standard of care after acute coronary syndrome (ACS). However, the benefit of this approach to prevent major adverse cardiovascular events has been demonstrated in only one randomised, placebo controlled trial. The Myocardial Ischemia Reduction with Aggressive Cholesterol Lowering (MIRACL) trial demonstrated that atorvastatin 80 mg daily, compared with placebo, reduced time to first occurrence of death, non-fatal myocardial infarction, resuscitated cardiac arrest, or hospitalisation for unstable angina (stroke not included) during the 16 week period following ACS. However, there were no significant effects on individual components of the composite endpoint except unstable angina. This led some to question whether early, intensive statin treatment reduces 'hard' events after ACS. Aim The burden of coronary heart disease after ACS, and therefore the efficacy of its treatment, depends not only on the occurrence of one ischaemic event, but rather on cumulative events experienced by patients. Accordingly, we conducted a post-hoc analysis of the MIRACL trial to examine the effect of atorvastatin on first as well as recurrent (i.e. total) hard cardiovascular events after ACS (death, myocardial infarction, stroke, and resuscitated cardiac arrest). Methods and Results In the 3086 patients who comprised the MIRACL trial, atorvastatin 80 mg did not reduce time to first hard event compared with placebo (hazard ratio 0.89, 95% confidence interval 0.72-1.10, P = 0.27). However, atorvastatin significantly reduced total hard events (hazard ratio 0.80, 95% confidence interval 0.66-0.97, P = 0.03). To prevent one hard event during the 16 weeks following ACS, only 11 patient-years of treatment with atorvastatin were required. Conclusion Early, intensive treatment with atorvastatin is an efficient intervention to reduce hard cardiovascular events after ACS.

Non-vitamin K Oral Anticoagulants Versus Warfarin for Patients with Atrial Fibrillation: Absolute Benefit and Harm Assessments Yield Novel Insights

BACKGROUND AND OBJECTIVES

Benefits and/or harms (including costs) of non-vitamin K oral anticoagulants (NOACs) versus warfarin therapy need appreciation in relative and absolute terms.

METHODS

Accordingly, we derived clinically relevant relative and absolute benefit/harm parameters for NOACs (apixaban, dabigatran, rivaroxaban, edoxaban) compared to warfarin from four clinical trials involving atrial fibrillation (AF) patients. For each trial, we tabulated patient numbers enduring four important outcomes and calculated unadjusted relative risk reduction (RRR) and number needed to treat (NNT)/year values (and 95% confidence intervals) for the NAOC compared to warfarin. These outcomes were as follows: stroke/systemic embolism (primary endpoint), hemorrhagic stroke, major bleeds, and death. We also addressed drug acquisition costs.

RESULTS

Each NOAC was noninferior to warfarin for primary-outcome prevention; RRRs were 12-33% and NNT/year values were 182-481, and all but one indicated statistically significant superiority. All the NOACs yielded statistically significant reductions in hemorrhagic stroke risk; RRRs were 42-74% and NNT/year values were 364-528. Major bleeding risk was comparable in both groups. Apixaban yielded a lower NNT/year for preventing death than for primary-outcome prevention. Compared to warfarin, NOAC acquisition costs were 70- to 140-fold greater.

CONCLUSIONS

For the primary outcome, the absolute benefits of NOACs were modest (NNT/year values being large). Reduced hemorrhagic stroke rates with NOACs could be due to superior embolic infarct prevention and fewer consequential hemorrhagic transformations. Among apixaban recipients, the absolute mortality benefit exceeded that for the primary outcome, indicating prevention of additional unrelated deaths. The substantially greater NOAC acquisition costs need viewing against probable greater safety and the avoidance of monitoring bleeding risks.

The Surgical Care Improvement Project Antibiotic Guidelines: Should We Expect More Than Good Intentions?

Since 2006, the Surgical Care Improvement Project (SCIP) has promoted 3 perioperative antibiotic recommendations designed to reduce the incidence of surgical site infections. Despite good evidence for the efficacy of these recommendations, the efforts of SCIP have not measurably improved the rates of surgical site infections. We offer 3 arguments as to why SCIP has fallen short of expectations. We then suggest a reorientation of quality improvement efforts to focus less on reporting, and incentivizing adherence to imperfect metrics, and more on creating local and regional quality collaboratives to educate clinicians about how to improve practice. Ultimately, successful quality improvement projects are behavioral interventions that will only succeed to the degree that they motivate individual clinicians, practicing within a particular context, to do the difficult work of identifying failures and iteratively working toward excellence.

Duration of dual antiplatelet therapy after drug-eluting stent implantation: Meta-analysis of large randomised controlled trials

Patients receive dual antiplatelet therapy (DAPT) for 6–12 months after drug-eluting stents (DES) implantation. The efficacy and safety of prolonged DAPT has been questioned. Therefore, we performed a meta-analysis on randomised trials comparing different DAPT durations. Literature was searched on trials comparing different DAPT durations. For inclusion, reports must report frequency of cardiovascular and bleeding events. Ten trials were included. Compared to 12 months, DAPT beyond 12 months was associated with fewer myocardial infarctions (OR 0.58 95%CI: 0.40–0.84) and stent thrombosis (OR 0.35 95%CI: 0.20–0.62), but more major bleeds (OR 1.60 95%CI: 1.22–2.11) and all-cause (OR 1.30 95%CI: 1.02–1.66) mortality. There was no significant alteration in risk of stroke (OR 0.93 95%CI: 0.66–1.31) or cardiac (OR 1.12 95%CI: 0.73–1.71) mortality. Compared to less than 12 months DAPT, 12 months DAPT did not reduce risk of myocardial infarction, stent thrombosis, strokes, cardiac or all-cause mortality, but increased the risk of major bleeds (OR 1.60 95%CI: 1.22–2.11). DAPT beyond 12 months reduce risk of myocardial infarction and stent thrombosis, but there is substantial increase in major bleeding risk and all-cause mortality which need to be addressed. DAPT beyond 12 months does not appear to alter the risk of stroke.

High-sensitivity cardiac troponin I and B-type natriuretic Peptide as predictors of vascular events in primary prevention: impact of statin therapy

Supplemental Digital Content is available in the text.

Background—

Cardiac troponin and B-type natriuretic peptide (BNP) concentrations are associated with adverse cardiovascular outcome in primary prevention populations. Whether statin therapy modifies this association is poorly understood.

Methods and Results—

We measured high-sensitivity cardiac troponin I (hsTnI) in 12 956 and BNP in 11 076 participants without cardiovascular disease in the Justification for the Use of Statins in Prevention: An Intervention Trial Evaluating Rosuvastatin (JUPITER) trial before randomization to rosuvastatin 20 mg/d or placebo. Nearly 92% of participants had detectable circulating hsTnI, and 2.9% of men and 4.1% of women had levels above proposed sex-specific reference limits of 36 and 15 ng/L, respectively. hsTnI concentrations in the highest tertile were associated with a first major cardiovascular event (adjusted hazard ratio [aHR], 2.19; 95% confidence interval, 1.56–3.06; P for trend <0.001). BNP levels in the highest tertile were also associated a first cardiovascular event (aHR, 1.94; 95% confidence interval, 1.41–2.68; P for trend <0.001). The risk of all-cause mortality was elevated for the highest versus the lowest tertiles of hsTnI (aHR, 2.61; 95% confidence interval, 1.81–3.78; P for trend <0.001) and BNP (aHR, 1.45; 95% confidence interval, 1.03–2.04; P for trend 0.02). Rosuvastatin was equally effective in preventing a first cardiovascular event across categories of hsTnI (aHR range, 0.50–0.60) and BNP (aHR range, 0.42–0.67) with no statistically significant evidence of interaction (P for interaction=0.53 and 0.20, respectively).

Conclusions—

In a contemporary primary prevention population, baseline cardiac troponin I and BNP were associated with the risk of vascular events and all-cause mortality. The benefits of rosuvastatin were substantial and consistent regardless of baseline hsTnI or BNP concentrations.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00239681.

Putting the diabetes risk due to statins in perspective: a re-evaluation using the complementary outcome

AIMS

Statins are used extensively to treat dyslipidemia and have been associated with significant clinical benefit that increases with dose. However, recent studies have associated statins with an excess risk of developing diabetes mellitus, which may offset the clinical benefit to patients. Adverse events related to intensive-dose statin therapy were revisited in light of recent data regarding the use of relative risks.

DATA SYNTHESIS

A meta-analysis was replicated with the event of interest redefined as the complementary outcome (no-onset of diabetes). Five randomised controlled trials that compared the risk of intense-dose with moderate-dose of statin therapy for the onset of diabetes with a follow-up greater than 12 months were included in the analysis. A reduction in the risk for no-onset of diabetes was found when intensive-dose statin therapy was compared with moderate-dose statin therapy, revealing a relative risk of 0.9908 (95%CI: 0.9849-0.99679). Over two years, one more patient was harmed by diabetes onset for every 237 patients exposed to intensive-dose statin therapy (95%CI: 123-3847) compared with standard dose statin therapy.

CONCLUSIONS

Statins are associated with only a very small increase in risk of diabetes mellitus. Previous research selected the outcomes with the lower baseline risks and therefore the actual risk associated with statins has been largely over-estimated.

The JUPITER trial: myth or reality?

The JUPITER trial is widely hailed as a landmark trial that has the potential to dramatically change the landscape of primary prevention of cardiovascular disease. Like most trials, however, it is not without its limitations. We address some of the common myths and misunderstandings that are underscored by the JUPITER trial. First, by its intentional and ill-advised exclusion of patients with low levels of high-sensitivity C-reactive protein (hsCRP), it is not possible to assess whether baseline hsCRP modifies treatment response to statins or whether it identifies patients most likely to benefit from statin therapy. Second, by stopping the trial early, one cannot rule out the possibility that the treatment benefit was overestimated and risk was underestimated, thereby precluding a reliable estimate of benefit/risk. Finally, as a consequence of early stopping, it is not possible to reliably assess the cost-effectiveness of primary prevention with rosuvastatin. Given these limitations, the attendant societal health policy implications remain largely unknown.

Effect of Antihypertensive Therapy on Incident Stroke in Cohorts With Prehypertensive Blood Pressure Levels

Background and Purpose—

Compared with normotensive individuals, there is a higher incidence of stroke in patients with hypertensive, as well as prehypertensive, blood pressure levels (ie, 120–139/80–89 mm Hg). Although several studies have shown that blood pressure reduction in hypertensive patients reduces the incidence of cardiovascular events, including stroke, it is still unknown whether treatment of prehypertensive blood pressure levels has a similar effect. We sought to determine whether reduction in blood pressure in the prehypertensive range reduces the incidence of stroke by performing a meta-analysis of randomized trials comparing an antihypertensive drug against placebo in cohorts with prehypertensive baseline blood pressure levels.

Methods—

Randomized controlled trials performed with the 95 different antihypertensive agents available in the market were identified using MEDLINE, returning a total of 2852 results. Exclusion criteria included: average blood pressure of ≥140/90 mm Hg at baseline, crossover studies, and lack of a control group receiving placebo.

Results—

A total of 16 trials involving 70 664 patients were included. Patients randomized to the active treatment arm had a statistically significant 22% reduction in the risk of stroke compared with placebo, with little heterogeneity among the trials (I 2 , 18.0%; RR, 0.78 [95% CI, 0.71–0.86]; P <0.000001). To prevent 1 stroke, 169 patients had to be treated with a blood-pressure-lowering medication for an average of 4.3 years.

Conclusions—

The risk of stroke is significantly reduced with antihypertensive therapy in cohorts with prehypertensive blood pressure levels. These findings can have important clinical implications.

Managing cardiovascular risk factors: trial evidence in women

Cardiovascular disease remains by far the leading cause of death for women worldwide. Despite a large body of research identifying effective interventions to reduce cardiovascular risk, translation into practice has been slow. This review pinpoints areas in particular need of improvement and summarizes gender-specific analyses in recent randomized trials assessing the impact of risk factor modulation on cardiovascular events.

Number Needed to Treat With Rosuvastatin to Prevent First Cardiovascular Events and Death Among Men and Women With Low Low-Density Lipoprotein Cholesterol and Elevated High-Sensitivity C-Reactive Protein: Justification for the Use of statins in Prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER)

Background— As recently demonstrated, random allocation to rosuvastatin results in large relative risk reductions for first cardiovascular events among apparently healthy men and women with low levels of low-density lipoprotein cholesterol but elevated levels of high-sensitivity C-reactive protein. However, whether the absolute risk reduction among such individuals justifies wide application of statin therapy in primary prevention is a controversial issue with broad policy and public health implications.

Methods and Results— Absolute risk reductions and consequent number needed to treat (NNT) values were calculated across a range of end points, timeframes, and subgroups using data from Justification for the Use of statins in Prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER), a randomized evaluation of rosuvastatin 20 mg versus placebo conducted among 17 802 apparently healthy men and women with low-density lipoprotein cholesterol <130 mg/dL and high-sensitivity C-reactive protein ≥2 mg/L. Sensitivity analyses were also performed to address the potential impact that alternative statin regimens might have on a similar primary prevention population. For the end point of myocardial infarction, stroke, revascularization, or death, the 5-year NNT within JUPITER was 20 (95% CI, 14 to 34). All subgroups had 5-year NNT values for this end point below 50; as examples, 5-year NNT values were 17 for men and 31 for women, 21 for whites and 19 for nonwhites, 18 for those with body mass index ≤25 kg/m 2 and 21 for those with body mass index greater than 25 kg/m 2 , 9 and 26 for those with and without a family history of coronary disease, 19 and 22 for those with and without metabolic syndrome, and 14 and 37 for those with estimated Framingham risks greater or less than 10%. For the net vascular benefit end point that additionally included venous thromboembolism, the 5-year NNT was 18 (95% CI, 13 to 29). For the restricted “hard” end point of myocardial infarction, stroke, or death, the 5-year NNT was 29 (95% CI, 19 to 56). In sensitivity analyses addressing the theoretical utility of alternative agents, 5-year NNT values of 38 and 57 were estimated for statin regimens that deliver 75% and 50% of the relative benefit observed in JUPITER, respectively. All of these calculations compare favorably to 5-year NNT values previously reported in primary prevention for the use of statins among hyperlipidemic men (5-year NNT, 40 to 70), for antihypertensive therapy (5-year NNT, 80 to 160), or for aspirin (5-year NNT, >300).

Conclusions— Absolute risk reductions and consequent NNT values associated with statin therapy among those with elevated high-sensitivity C-reactive protein and low low-density lipoprotein cholesterol are comparable if not superior to published NNT values for several widely accepted interventions for primary cardiovascular prevention, including the use of statin therapy among those with overt hyperlipidemia.

Clinical Trial Registration— clinicaltrials.gov. Identifier NCT00239681.

Moving toward new statin guidelines in a post-JUPITER world: principles to consider

The recently completed study Justification for the Use of Statins in Prevention: An Intervention Trial Evaluating Rosuvastatin (JUPITER) demonstrates that statin therapy reduces vascular events in apparently healthy men and women with low levels of low-density lipoprotein cholesterol (mean, 104 mg/dL) who are at elevated risk due to high-sensitivity C-reactive protein levels greater than 2 mg/L. Among 17,802 trial participants, rosuvastatin resulted in a 44% reduction in the primary end point of all vascular events (P < 0.00001), a 54% reduction in myocardial infarction (P = 0.0002), a 48% reduction in stroke (P = 0.002), a 46% reduction in need for arterial revascularization (P < 0.001), and a 20% reduction in all-cause mortality (P = 0.02). All subgroups with elevated high-sensitivity C-reactive protein benefited, including those traditionally considered to be at low risk, such as women, nonsmokers, and those with Framingham risk scores less than 10%. Absolute risk reductions within JUPITER result in a number needed to treat at 5 years of 25, a value comparable or superior to that of other interventions routinely used in primary prevention, including statin therapy among those with hyperlipidemia. Although lifestyle interventions remain critical, the screening and treatment strategy tested in JUPITER is likely to impact on new guidelines for cardiovascular disease prevention.

Testing the inflammatory hypothesis of atherothrombosis: scientific rationale for the cardiovascular inflammation reduction trial (CIRT)

While inflammation is a crucial component of atherothrombosis and patients with elevated inflammatory biomarkers such as high sensitivity C-reactive protein (hsCRP) are at increased vascular risk, it remains unknown whether inhibition of inflammation per se will lower vascular event rates. The recently completed JUPITER (N Engl J Med 2008, 359, 2195) trial demonstrates that statins reduce myocardial infarction, stroke, and all-cause mortality among healthy individuals with low cholesterol and elevated hsCRP. However, a direct test of the inflammatory hypothesis of atherothrombosis requires an agent that inhibits inflammation without impacting other components of the atherothrombotic process, and has an acceptable safety profile for a trial setting. On this basis, the cardiovascular inflammation reduction trial (CIRT) proposes to allocate 7000 stable coronary artery disease patients with persistent elevations of hsCRP to placebo or very-low-dose-methotrexate (VLDM, 10 mg weekly), a proven anti-inflammatory regimen that reduces TNFalpha, IL-6, and CRP levels and is in wide use among rheumatoid arthritis patients. If successful, CIRT would both confirm the inflammatory hypothesis of atherothrombosis and open novel approaches to the treatment and prevention of cardiovascular disorders.

Does Treating Subclinical Hypothyroidism Improve Markers of Cardiovascular Risk?

Subclinical hypothyroidism is defined as an elevated serum thyroid-stimulating hormone (TSH) level in the face of normal free thyroid hormone values. The overall prevalence of subclinical hypothyroidism is 4-10% in the general population and up to 20% in women aged >60 years. The potential benefits and risks of therapy for subclinical hypothyroidism have been debated for 2 decades, and a consensus is still lacking. Besides avoiding the progression to overt hypothyroidism, the decision to treat patients with subclinical hypothyroidism relies mainly on the risk of metabolic and cardiovascular alterations. Subclinical hypothyroidism causes changes in cardiovascular function similar to, but less marked than, those occurring in patients with overt hypothyroidism. Diastolic dysfunction both at rest and upon effort is the most consistent cardiac abnormality in patients with subclinical hypothyroidism, and also in those with slightly elevated TSH levels (>6 mIU/L). Moreover, mild thyroid failure may increase diastolic blood pressure as a result of increased systemic vascular resistance. Restoration of euthyroidism by levothyroxine replacement is generally able to improve all these abnormalities. Early clinical and autopsy studies had suggested an association between subclinical hypothyroidism and coronary heart disease, which has been subsequently confirmed by some, but not all, large cross-sectional and prospective studies. Altered coagulation parameters, elevated lipoprotein (a) levels, and low-grade chronic inflammation are regarded to coalesce with the hypercholesterolemia of untreated patients with subclinical hypothyroidism to enhance the ischemic cardiovascular risk. Although a consensus is still lacking, the strongest evidence for a beneficial effect of levothyroxine replacement on markers of cardiovascular risk is the substantial demonstration that restoration of euthyroidism can lower both total and low-density lipoprotein-cholesterol levels in most patients with subclinical hypothyroidism. However, the actual effectiveness of thyroid hormone substitution in reducing the risk of cardiovascular events remains to be elucidated. In conclusion, the multiplicity and the possible reversibility of subclinical hypothyroidism-associated cardiovascular abnormalities suggest that the decision to treat a patient should depend on the presence of risk factors, rather than on a TSH threshold. On the other hand, levothyroxine replacement therapy can always be discontinued if there is no apparent benefit. Levothyroxine replacement therapy is usually safe providing that excessive administration is avoided by monitoring serum TSH levels. However, the possibility that restoring euthyroidism may be harmful in the oldest of the elderly population of hypothyroid patients has been recently raised, and should be taken into account in making the decision to treat patients with subclinical hypothyroidism who are aged >85 years.

Lipids and stroke: the opportunity of lipid-lowering treatment

Dyslipemia is a clear risk factor (RF) for ischemic heart disease and peripheral artery disease, but its relation with ischemic stroke (IS) is not so clear. HMG-CoA reductase inhibitor drugs or statins (simvastatin, atorvastatin, pravastatin) reduce the relative risk of IS by between 18 and 51% in patients with IHD, in patients with high vascular disease risk and in hypertensive patients with other RFs, acute coronary syndrome, and type 2 diabetes mellitus. According to the guidelines for use, statins are indicated in the majority of patients with IS since the risk is equivalent to that of IHD or high vascular disease risk. In view of the existing clinical evidence of benefit, it would not seem unreasonable to proceed with treatment of patients using statins while awaiting specific studies justifying their use. The non-lipid-lowering mechanisms of the statins and results of studies, such as the Heart Protection Study, provide evidence for widening the indications of statins beyond the prevention of dyslipemia, as a new therapeutic approach in the prevention of IS in patients with plasma levels of total cholesterol or low density lipoproteins currently considered within the normal distribution. The neuroprotective role, which these drugs may play in the acute phase of cerebral ischemia, remains to be clarified, but very recent evidence suggests that such patients may also benefit.

Rhythm vs. rate control of atrial fibrillation meta-analysed by number needed to treat

BACKGROUND

Whenever feasible, rhythm control of atrial fibrillation (AF) was generally preferred over rate control, in the belief that it offered better symptomatic relief and quality of life, and eliminated the need for anticoagulation. However, recent trials appear to challenge these assumptions.

AIMS

To explore the desirability of rhythm vs. rate control of AF by systematic review of pertinent, published, randomized controlled trials (RCTs) and a meta-analysis by number needed to treat (NNT) year(-1), with respect to diverse clinically important outcomes.

METHODS

RCTs of outcome primarily comparing rate vs. rhythm control in patients with spontaneous AF were identified. For each outcome and assuming rhythm control to be the active treatment, relative risk reduction (RRR) and NNT year(-1) were derived for individual trials together with an NNT year(-1) for all trials combined; corresponding 95% confidence intervals (CI) were also calculated. Adverse drug reaction (ADR) and quality of life reporting were also assessed.

RESULTS

In all, data from five suitable RCTs (entailing 5239 patients) were analysed. For hospitalization, available RRRs and NNT year(-1) values were all clinically and statistically significant. Overall, one additional patient was hospitalized for every 35 assigned to rhythm control (95% CI 27, 48). For the endpoints of death, 'ischaemic' stroke and 'non-CNS' bleeding, there was no significant difference. ADRs were significantly more common in rhythm control patients, whereas quality of life assessments revealed no difference. Thromboembolism was associated with cessation of or subtherapeutic anticoagulation, irrespective of treatment assignment.

CONCLUSION

Reduced risk of hospitalization and non-inferiority for other endpoints all favour rate control, the less costly strategy. If symptoms of AF are not a problem, treatment should target optimizing rate control and more widespread and effective prophylactic anticoagulation.

Suboptimal statin adherence and discontinuation in primary and secondary prevention populations

OBJECTIVES

To compare statin nonadherence and discontinuation rates of primary and secondary prevention populations and to identify factors that may affect those suboptimal medication-taking behaviors.

DESIGN

Retrospective cohort utilizing pharmacy claims and administrative databases.

SETTING

A midwestern U.S. university-affiliated hospital and managed care organization (MCO).

PATIENTS

Non-Medicaid MCO enrollees, 18 years old and older, who filled 2 or more statin prescriptions from January 1998 to November 2001; 2258 secondary and 2544 primary prevention patients were identified.

MEASUREMENTS

Nonadherence was assessed by the percent of days without medication (gap) over days of active statin use, a measurement known as cumulative multiple refill-interval gap (CMG). Discontinuation was identified by cessation of statin refills prior to the end of available pharmacy claims data.

RESULTS

On average, the primary and secondary groups went without medication 20.4% and 21.5% of the time, respectively (P=.149). Primary prevention patients were more likely to discontinue statin therapy relative to the secondary prevention cohort (relative risk [RR], 1.24; 95% confidence interval [CI], 1.08 to 1.43). Several factors influenced nonadherence and discontinuation. Fifty percent of patients whose average monthly statin copayment was < US dollars 10 discontinued by the end of follow-up (3.9 years), whereas 50% of those who paid >US dollars 10 but <or=US dollars 20 and >US dollars 20 discontinued by 2.2 and 1.0 years, respectively (RR, 1.39 and 4.30 relative to <US dollars 10 copay, respectively).

CONCLUSIONS

Statin nonadherence and discontinuation was suboptimal and similar across prevention categories. Incremental efforts, including those that decrease out-of-pocket pharmaceutical expenditures, should focus on improving adherence in high-risk populations most likely to benefit from statin use.

Meta-analysis of large randomized controlled trials to evaluate the impact of statins on cardiovascular outcomes

AIMS

Since 2002, there have been five major outcome trials of statins reporting findings from more than 47,000 subjects. As individual trial results differed, we performed a meta-analysis to ascertain the effectiveness and safety of statins overall and in subgroups. The aim of the study was to estimate the effect of statins on major coronary events and strokes, all-cause mortality and noncardiovascular mortality, and in different subgroups.

METHODS

PubMed was searched for trials published in English. Randomized placebo-controlled statin trials with an average follow up of at least 3 years and at least 100 major coronary events were included. For each trial, the statin used, number and type of subjects, proportion of women, mean age and follow up, baseline and change in lipid profile, cardiovascular and non-cardiovascular outcomes were recorded.

RESULTS

Ten trials involving 79,494 subjects were included in the meta-analysis. Due to heterogeneity, ALLHAT-LLT was excluded from some analyses. Statin therapy reduced major coronary events by 27% (95%CI 23, 30%), stroke by 18% (95%CI 10, 25%) and all-cause mortality by 15% (95%CI 8, 21%). There was a 4% (95%CI -10, 3%) nonsignificant reduction in noncardiovascular mortality. The reduction in major coronary events is independent of gender and presence of hypertension or diabetes. The risk reduction was greater in smokers (P < 0.05). Coronary events were reduced by 23% (95%CI 18, 29%) in pravastatin trials and 29% (95%CI 25, 33%) in five trials using other statins. Pravastatin reduced strokes by 12% (95%CI 1, 21%) whilst other statins reduced strokes by 24% (95%CI 16, 32%) (P = 0.04).

CONCLUSIONS

Statins reduce coronary events, strokes and all-cause mortality without increasing noncoronary mortality. The benefits accrue in men and women, hypertensives and normotensives, diabetics and nondiabetics, and particularly in smokers. Pravastatin appears to have less impact on strokes.

Efficacy and safety of fluvastatin therapy for hypercholesterolemia after heart transplantation

BACKGROUND

Hypercholesterolemia is frequent after heart transplantation. Statins can reduce cholesterol levels but their use in heart transplant patients is complicated by pharmacokinetic interactions with cyclosporin and the risk of serious adverse effects including rhabdomyolysis. Fluvastatin has been used safely to treat hypercholesterolemia in renal transplant patients but there are few data relating to its use after heart transplantation. Therefore, we conducted a randomised blinded placebo controlled trial.

METHODS AND RESULTS

Seventy-nine patients, 3 months to 12 years after heart transplantation with a low density lipoprotein (LDL) cholesterol between 3.5 and 8.0 mmol/l were randomly assigned, in a 2:1 ratio, to receive either fluvastatin 40 mg od (n=52) or matching placebo (n=27). Changes in total cholesterol (TC) in the fluvastatin and placebo groups were -17.0% and +4.5%, respectively, (p<0.001); the corresponding changes in LDL were -20.5% and +4.8% (P<0.001) and in triglycerides -14.5% and +7.1% (p=0.012) at the end of the 1-year study period. Withdrawals were more frequent in the fluvastatin group (23% vs. 11% p=0.24). Two deaths occurred during the study (the rate expected from International Society of Heart Lung Transplantation registry) and appeared to be unrelated to the study medication. There were no episodes of rhabdomyolysis or other serious drug-related side effects.

CONCLUSIONS

Fluvastatin (40 mg/day) was both an effective and a safe treatment for hypercholesterolemia in patients who had undergone heart transplantation more than 3 months previously.

Evidence-Based Endocrinology

Evidence-based medicine is the judicious, conscientious, and explicit use of the best available evidence from clinical research in making clinical decisions. This definition recognizes a hierarchy of evidence that arranges study designs by their susceptibility to bias. The top of the hierarchy includes n-of-1 trials, systematic reviews of randomized trials, and single randomized trials reporting patient-important outcomes. The bottom of the hierarchy includes physiologic studies and unsystematic clinical observations. The definition posits that evidence alone is never enough to guide clinical decisions. In addition to evidence from clinical research, decision making requires careful and expert assessment of the patient's circumstances and elicitation of the patient's values and preferences. The latter should drive decisions, particularly when the trade-offs (of benefit and risk) are close or unclear. The evidence-based medicine process involves: (i) asking an answerable question; (ii) acquiring the best available evidence; (iii) appraising the evidence to judge the strength of inference of its results; and (iv) applying the results to the individual patient. Evidence-based endocrinology is hindered by limited high-level evidence assessing patient-important outcomes, limited systematic summaries of this evidence, lack of time, and lack of systematic training of endocrinologists in evidence-based medicine. Current endocrine practice may require a redesign to enhance the role of endocrinologists as information brokers for colleagues and patients. In the last 10 years, evidence-based medicine has matured as a philosophy of clinical care and medical education. An appraisal of its role in endocrinology awaits the pervasion of its principles into all of endocrine practice.

Screening Coronary Arteriography in the Primary Prevention of Coronary Artery Disease

Recent studies indicate an expansion of the population eligible for primary prevention of coronary artery disease with lipid-lowering therapy. This change has led to the unnecessary treatment of many individuals and an overall decreased effectiveness of medication with potentially significant side effects. If instead, the asymptomatic population is screened for the presence of early coronary artery disease (CAD), lipid lowering can be targeted to those who can truly benefit. The prevalence of asymptomatic CAD in men older than 50 years of age approaches 20% and arteriography is currently the best available test to identify these men. The approximate complication rate of arteriography in such a population (1 or 2 per 10,000) approaches that of other screening tests. Although insufficient data exists for formal cost analysis, approximations indicate significant savings for arteriographically targeted treatment of at-risk asymptomatic individuals. The authors show that coronary arteriography is a potentially safe and cost-effective method of screening an asymptomatic adult population for presence of early CAD, allowing for the targeting of lipid lowering to those who can benefit most from this therapy.

[Autoimmune thyroiditis. Treatment with thyroid gland hormones in subclinical hypothyroidism or already in euthyroid state?]

In patients with subclinical hypothyroidism thyroid hormone therapy should be recommended more often with respect to analysis of effectiveness and risks. There is no cost-difference between treated patients and those who undergo thyroid hormone controls only, but thyroid hormone therapy probably induces improvement of clinical and laboratory parameters and reduction of cardiovascular risk factors. These therapeutic effects have to be elucidated in clinical prospective studies. Thyroid hormone therapy of patients with autoimmune thyroiditis and still euthyroid function obviously inhibits the autoimmune process and development of hypothyroidism. A final recommendation, however, can be given after the data of clinical studies with larger populations are available.

Stratifying the risk of NSAID-related upper gastrointestinal clinical events: results of a double-blind outcomes study in patients with rheumatoid arthritis

BACKGROUND & AIMS

Epidemiologic data indicate that the risk of nonsteroidal anti-inflammatory drug (NSAID)-related gastrointestinal (GI) clinical events varies based on patients' clinical characteristics. The authors determined risk factors for NSAID-related clinical upper GI events and the event rates, absolute risk reductions, and numbers needed to treat for individual risk factors for a nonselective NSAID and a selective cyclooxygenase 2 inhibitor in a double-blind outcomes trial.

METHODS

Eight thousand seventy-six rheumatoid arthritis patients aged >or=50 years (or >or=40 on corticosteroid therapy) were randomly assigned to rofecoxib 50 mg daily or naproxen 500 mg twice daily for a median of 9 months. The development of clinical upper GI events (bleeding, perforation, obstruction, and symptomatic ulcer identified on clinically indicated work-up) was assessed.

RESULTS

Significant risk factors included prior upper GI events, age >or=65, and severe rheumatoid arthritis (RR, 2.3-3.9). Patients administered naproxen who had prior upper GI complications or who were aged >or=75 years had 18.84 or 14.46 events per 100 patient-years, and the risk of events remained constant over time. The reduction in events with rofecoxib was similar in high- and low-risk subgroups (RR, 0.31-0.68). The number needed to treat with rofecoxib instead of naproxen to avert 1 GI event was 10-12 in highest risk patients (prior event, age >or=75 years, or severe rheumatoid arthritis), 17-33 in patients with other risk factors, and 42-106 in low-risk patients.

CONCLUSIONS

NSAID-related GI events increase dramatically with risk factors such as prior events or older age. Ten to twelve high-risk patients need to be treated with a protective strategy such as the selective cyclooxygenase 2 inhibitor, rofecoxib, to avert a clinical GI event.

Gastrointestinal safety of coxibs and outcomes studies: what's the verdict?

Although nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used, their main limitation is gastrointestinal (GI) injury. Two double-blind, randomized, outcomes trials were conducted to determine the incidence of clinical GI events with the coxibs, rofecoxib and celecoxib, compared with nonselective NSAIDs. The VIGOR study (VIOXX Gastrointestinal Outcomes Research) compared rofecoxib with naproxen, and the CLASS study (Celecoxib Long-term Arthritis Safety Study) compared celecoxib with ibuprofen and diclofenac. The VIGOR trial revealed a relative risk reduction for clinical upper GI events of 50% with rofecoxib, and a 60% reduction in complicated events. In the CLASS study, the 23% reduction in complicated ulcers with celecoxib did not reach statistical significance (P = 0.45), although when all clinical events were examined, the 34% reduction was significant (P = 0.04). However, low-dose aspirin use, which was allowed in the CLASS study, may have influenced the results. A subgroup analysis in the patients who did not take aspirin revealed a nonsignificant 45% reduction in complicated events with celecoxib (P = 0.19), and a 47% reduction in complicated and symptomatic ulcers (P = 0.02).

Treatment of hypertension to prevent stroke: translating evidence into clinical practice

Although programs such as the National High Blood Pressure Education Project emphasize that all patients with hypertension should be treated, it is perhaps natural for physicians to question the usefulness of aggressively treating those patients who have modestly elevated blood pressure levels but are otherwise healthy, asymptomatic individuals. Using the example of stroke, this review summarizes the clinical trial data demonstrating the efficacy of antihypertensive therapy in patients with severe and nonsevere forms of hypertension. Suggestions are made that will help practitioners to apply results from the published literature in clinical practice. The evidence suggests that treating patients with nonsevere hypertension would prevent a larger proportion of the population-wide burden of stroke than treating only those with more severe hypertension. Helping physicians to understand and apply this evidence will bring us closer to the goal of population-wide treatment and control of high blood pressure.

Number needed to treat: caveat emptor

Number needed to treat (NNT)-the inverse of the absolute risk reduction resulting from an intervention-was introduced as a yardstick to describe the harm as well as the benefit of therapeutic maneuvers. Analysis using NNT works well when comparing two or more interventions that have their impact over the same period of time in similar populations or patients. Under other conditions, however, analysis based on NNT can produce results that diverge widely from the impact that the interventions can be expected to have on risk of death. This can happen either for entire populations or for an individual when comparing NNTs for interventions which have their effects on different subsets of the population or when comparing interventions which have their effects over different periods of time. We demonstrate how this can occur by comparing the NNTs and effect of intervention on deaths in a population for automatic implantable cardioverter defibrillators (AICDs), heart transplantation, and cholesterol lowering through nutritional intervention with plant stanol ester.