Deciphering cholesterol treatment guidelines: a clinician's perspective

Prevention of Cardiovascular Disease

Cardiovascular disease remains the leading cause of death in the United States and worldwide. Prevention of cardiovascular disease is an achievable goal. A rigorous 2010 analysis by the World Health Organization suggests that reducing risk factors in young adults and maintaining an optimum risk profile through age 50 could prevent 90% of atherosclerotic cardiovascular disease events. Misinformation and poor implementation of proven preventive strategies, misplaced fears of medications, or incorrect understanding of ideal dietary and lifestyle choices all contribute to poor risk profiles. Every patient deserves an individualized prescription for cardiovascular disease prevention incorporating strategies to control modifiable cardiovascular risk factors.

Current Consensus and Controversies in Guidelines for Lipid and Hypertension Management in Diabetes

Despite major advances, many patients with diabetes are currently achieving suboptimal control of lipids and blood pressure. The new cholesterol guidelines by the ACC/AHA have reignited the emphasis on more intensive treatment with statins in the population at high risk of CVD, including those with diabetes. While these guidelines do not include specific lipid goals, several other guidelines have retained previously defined risk-based LDL-C and non-HDL-C goals. More recent data indicate potential benefits in CVD outcomes with non-statin therapy added to statin therapy. On-going long-term trials with PCSK-9 inhibitors may help answer the question of the benefits and safety of very low LDL-C. Regarding the blood pressure guidelines, there remains an inconsistency of evidence for targets to reduce CVD outcomes. The ACCORD trial weighted heavily in the recent meta-analyses, leading to currently recommended goal of <140/90 mmHg. Studies targeting blood pressure goals of <130 mmHg in younger patients with diabetes, including sub-populations of interest, may help solve the controversy. Until we have these data, perhaps it is time to shift our focus from a rigid blood pressure target to risk-based goals.

Determining optimal threshold for statins prescribing: individualization of statins treatment for primary prevention of cardiovascular disease

RATIONALE, AIMS AND OBJECTIVES

The American College of Cardiology and American Heart Association (ACC/AHA) statin guidelines recommend that people with risk of cardio-vascular disease (CVD) ≥7.5% over 10 years should be treated with statins. This recommendation ignores individual patient CVD risks and preferences. We compared the ACC/AHA guidelines to the following management strategies a) individualized statins treatment based on Framingham Risk Score (FRS), b) treat none, c) treat all.

METHODS

We employed regret-based decision curve analysis to evaluate the optimal treatment strategy. We used data on 5013 participants from the second generation of the Framingham Heart Study. We assessed regret of each treatment strategy [treat according to FRS vs. treat none vs. treat all] as a function of emotionally felt loss of treatment benefits and incurred treatment harms. We calculated the difference between regret associated with one strategy compared with the other and expressed it as Net Expected Regret Difference (NERD). Two strategies are identical if NERD = 0.

RESULTS

Treatment according to ACC/AHA guidelines represents the optimal strategy only if the patient values avoiding heart disease 12 times more than harms related to statins. For values of benefit/harms (B/H) <12, treatment according to FRS represents the optimal strategy. For B/H <3, 'treat none' represents equally acceptable strategy. Adopting a threshold of 10% recommended by other professional organizations would decrease over-treatment by more than 60% without significantly affecting under-treatment.

CONCLUSION

Under most realistic scenarios, individualizing statins treatment, or not recommending statins at all, represents the optimal strategy for primary prevention of heart disease.

Increasing trend of diabetes combined with hypertension or hypercholesterolemia: NHANES data analysis 1999-2012

In order to prevent cardiovascular endpoints, control of diabetes, hypertension and hypercholesterolemia is a necessity as those risk factors frequently occur in combination. Prevalence trends of concurrent diabetes, hypertension and hypercholesterolemia in 36,673 subjects were obtained from the National Health and Nutrition Examination Survey (NHANES) from 1999–2012. The prevalence of concurrent diabetes, hypertension and hypercholesterolemia increased from 3% in 1999–2000 to 6.3% in 2011–2012 (P < 0.001). The diabetes with concurrent hypertension or hypercholesterolemia incidences also increased significantly, while the occurrence of concurrent hypertension and hypercholesterolemia was stable over the study period. Overall medical drug treatments for concurrent diabetes, hypertension, hypercholesterolemia were improved from 69.8% in 1999–2006, to 82.4% in 2007–2012 (P = 0.002). Treatment cost coverage rates in any combinations with diabetes were 79–82.4% and 90.7% in the subgroup of concurrent hypertension and hypercholesterolemia. General treatment goal achievement rates were <25%, the lowest rate being 14.2% in the subject groups with three combined risk factors. The treatment goal achievement rates in two subgroups with concurrent diabetes were 20.1% (with hypertension) and 17% (with hypercholesterolemia) and 24.5% in the group without diabetes. Cost coverage improved in all combinations, but the general treatment goal achievement rates were low, especially in the groups with concurrent diabetes.

Statin-induced diabetes: incidence, mechanisms, and implications

Persuasive data from many randomized controlled trials and large, long-term observational studies indicate a modestly increased risk for the emergence of new diabetes after statin initiation. Several meta-analyses of many statin trials as well as longitudinal population-based studies suggest that the risk factors for diabetes in statin-treated persons include underlying risk for diabetes at baseline (specifically features of metabolic syndrome), the intensity of statin therapy, certain genetic traits independent of diabetes risk, and adherence to lifestyle factors. Limited data suggest statins modestly worsen hyperglycemia and A1c levels in those with pre-existing diabetes or glucose intolerance. The precise mechanism(s) of diabetogenesis with statin therapy are unclear, but impaired insulin sensitivity and compromised β cell function via enhanced intracellular cholesterol uptake due to inhibition of intracellular cholesterol synthesis by statins, as well as other mechanisms, may be involved. Furthermore, while statins are known to have anti-inflammatory effects, it is hypothesized that, under dysmetabolic conditions, they might have pro-inflammatory effects via induction of certain inflammasomes. This concept requires further elucidation in the human. Finally, it is clear that the risk–benefit ratio for cardiovascular disease events is strongly in favor of statin therapy in those at risk, despite the emergence of new diabetes. Adherence to lifestyle regimen is critical in the prevention of new diabetes on statins.