Israel Medical Association Journal

Despite the application of recommended guideline-driven therapies and optimal medical interventions, individuals with established cardiovascular disease remain susceptible to additional cardiovascular incidents, a phenomenon referred to as residual risk. Analyses of clinical trial data reveal significant residual cardiovascular risk in all treated patients, even in the setting of optimal LDL-C reduction, thus enforcing the need to revise the algorithms beyond focusing on LDL-C levels. We present a case that highlights the problem of residual risk upon well controlled LDL-C levels and provide insights for additional measures for residual risk reduction.

Background: Coronary heart disease (CHD) patients are considered high cardiovascular risks. Guidelines recommend low-density lipoprotein cholesterol (LDL-C) target levels below 55 mg/dl with > 50% reduction from baselines. These levels can be reached by a combination of statins, ezetimibe, and anti-protein convertase subtilisin/kexin type 9 (anti-PCSK9) agents. Our clinical impression was that CHD patients do not reach LDL-C target levels, despite the wide availability.

Objectives: To evaluate whether hospitalization would result in changes in lipid lowering regimens and short-term compliance.

Methods: We conducted a retrospective cohort study using data of CHD patients who were admitted to internal medicine wards at Clalit Health Services medical centers because of anginal syndrome during 2020–2022. The data were evaluated for demographic and clinical characteristics; LDL-C level at admission, 6 months previously, and 3 months and 6–9 months after discharge; rates of reaching LDL-C target levels; and lipid lowering treatment at admission, discharge, and 6–9 months after.

Results: The cohort included 10,540 patients. One-third and three-quarters did not have lipids level measurements up to 6 months before and during hospitalization, respectively. Only one-fifth of the patients reached LDL-C values before and during admission (median LDL-C 72 mg/dl; range 53–101). Approximately half were treated with high-dose potent statins. Only 10% were treated with ezetimibe. Hospitalization did not have a clinically significant effect on short-term lipid lowering treatment or LDL-C levels.

Conclusions: Gaps were noted between guidelines and clinical practice for reaching LDL-C target levels. Further education and strict policy are needed.

Background: The use of proprotein convertase subtilisin/kexin type 9 monoclonal antibodies (PCSK9 mAbs) is emerging for lowering low-density lipoprotein cholesterol (LDL-C). However, real-world data is lacking for their use among elderly patients.

Objective: To define the characteristics of elderly patients treated with PCSK9 mAbs and to evaluate the efficacy and tolerability compared with younger patients.

Methods: We conducted a retrospective cohort study of elderly patients (≥ 75 years at enrollment) treated with PCSK9 mAbs for primary and secondary cardiovascular prevention. Data were retrieved for demographic and clinical characteristics; indications for treatment; agents and dosages; concomitant lipid lowering treatment; LDL-C levels at baseline, 6, 12 months, and at the end of follow up. Data also included achieving LDL-C target levels and adverse effects.

Results: The cohort included 91 elderly patients and 92 younger patients, mean age 75.2 ± 3.76 and 58.9 ± 7.4 years (P < 0.0001). Most patients (82%, 80%) were in high/very high-risk categories. For almost all (98%, 99%), the indication was statin intolerance, with PCSK9 mAb monotherapy the most prevalent regimen. The average follow-up was 38.1 ± 20.5 and 30.9 ± 15.8 months (P = 0.0258). Within 6 months the LDL-C levels were reduced by 57% in the elderly group and by 59% in the control group (P = 0.2371). Only 53% and 57% reached their LDL-C target levels. No clinically significant side effects were documented.

Conclusion: PCSK9 mAbs have similar effects and are well tolerated among elderly patients as in younger patients.

Background: While earlier studies indicated that cholesterol levels decrease significantly after an acute myocardial infarction (MI), a more recent study refuted this observation. 

Objectives: To assess changes in plasma lipid levels after onset of acute MI, and determine important predictors of lipid dynamics.

Methods: We prospectively measured lipid levels of patients who presented with an acute MI. Blood samples were drawn on admission to the hospital (day 1), after fasting at least 12 hours overnight (day 2), and on the 4th day of hospitalization (day 4). 

Results: Of 67 acute MI patients, 30 were admitted for ST elevation MI (STEMI) and 37 for non-STEMI. Both total cholesterol and low density lipoprotein cholesterol (LDL-C) levels decreased significantly (by 9%) in the 24 hours after admission and by 13% and 17% respectively on day 4. High density lipoprotein cholesterol (HDL-C) levels as well as triglycerides did not change significantly. Independent predictors of LDL-C decrease were the presence of diabetes mellitus [odds ratio (OR) 6.73, P = 0.01), and elevated cardiac troponin T (cTnT) levels (OR 1.81, P < 0.04).

Conclusions: LDL-C levels decrease significantly after an acute MI. The reduction is correlated with cTnT levels. Diabetes is a strong independent predictor of LDL-C decrease. In acute MI patients only measurements taken within 24 hours of onset should be used to guide selection of lipid-lowering medication.

 

Background: The introduction of more potent statins such as atorvastatin and rosuvastatin in Israel was accompanied by massive advertising about their superiority.

Objectives: To assess the need for switching therapy from older statins to more potent ones among diabetic patients with uncontrolled hypercholesterolemia.

Methods: Data on all diabetic patients over 30 years old attending two urban clinics were extracted and analyzed. For each patient we checked the last low density lipoprotein-cholesterol measurements for the year 2006, the brand and the dose of cholesterol-lowering medications, prescriptions and actual purchasing over a 4 month period prior to the last LDL-C[1] measurement, and whether treatment changes were necessary to achieve the LDL-C target (100 mg/dl or 70 mg/dl).

Results: The study population comprised 630 patients, age 66.7 ± 12.6 years, of whom 338 (53.6%) were women. Of the 533 (84.6%) patients whose LDL-C was measured in 2006, 45 (8.1%) had levels < 70 mg/dl and 184 (33.3%) had levels of 70 mg/dl < LDL-C < 100 m/dl.  The reasons for LDL-C > 100 mg/dl were patients not prescribed cholesterol-lowering drugs (38.3%), partial compliance (27.2%), and under-dosage of statins (15.4%); only 7.7% needed to switch to a more potent statin. Reasons for LDL-C > 70 mg/dl were patients not prescribed cholesterol-lowering drugs (34.3%), partial compliance (22.0%), and under-dosage of statins (26.6%); only 8.7% needed to switch to a more potent statin.

Conclusions: Only a small minority of diabetic patients with uncontrolled hypercholesterolemia need one of the potent statins as the next treatment step. More emphasis on compliance and dose adjustment is needed to achieve the target LDL-C level.

Background: Hyperlipidemia is a major risk factor for coronary heart disease. Reducing low density lipoprotein-cholesterol can significantly reduce the risk of CHD[1], but many patients fail to reach the target LDL-C[2] goals due to low doses of statins or low compliance.

Objectives: To treat high risk patients with atorvastatin in order to reach LDL-C goals (either primary or secondary prevention) of the Israel Atherosclerosis Society.

Methods: In this open-label study of 3,276 patients (1,698 of whom were males, 52%), atorvastatin 10 mg was given as a first dose, with follow-up and adjustment of the dose every 6 weeks. While 1,670 patients did not receive prior hypolipidemic treatment, 1,606 were treated with other statins, fibrates or the combination of both.

Results: After 6 weeks of treatment, 70% of the patients who did not receive prior hypolipidemic medications and who needed primary prevention reached target LDL-C levels. Interestingly, a similar number of patients on prior hypolipidemic treatment reached the LDL-C goals for primary prevention. The patients treated with other statins, fibrates or both did not reach the LDL-C treatment goals. Only 34% of all patients who needed secondary prevention reached the ISA[3] LDL-C target of 100 mg/dl. Atorvastatin proved to be completely safe; only two patients had creatine kinase elevation above 500 U/L, and another six had mild CK[4] elevation (<500 U/L). None of the patients had clinical myopathy, and only one had to be withdrawn from the study.

Conclusion: Atorvastatin is a safe and effective drug that enables most patients requiring primary prevention to reach LDL-C goal levels, even with a low dose of 10 mg. Patients in need of secondary prevention usually require higher doses of statins.

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