Statin use in Australian children: a retrospective audit of four pediatric hospitals

Promoting cardiovascular health post-transplant through early diagnosis and adequate management of hypertension and dyslipidemia

Despite correction of underlying solid organ failure by transplantation, pediatric transplant recipients still have increased mortality rates compared to the general pediatric population, in part due to increased cardiovascular risk. In particular, pediatric kidney and non-kidney transplant recipients with chronic kidney disease have significant cardiovascular risk that worsens with declining kidney function. Biomarkers associated with future cardiovascular risk such as casual and ambulatory hypertension, dyslipidemia, vascular stiffness and calcification, and left ventricular hypertrophy can be detected throughout the post-transplant period and in patients with stable kidney function. Among these, hypertension and dyslipidemia are two potentially modifiable cardiovascular risk factors that are highly prevalent in kidney and non-kidney pediatric transplant recipients. Standardized approaches to appropriate BP measurement and lipid monitoring are needed to detect and address these risk factors in a timely fashion. To achieve sustained improvement in cardiovascular health, clinicians should partner with patients and their caregivers to address these and other risk factors with a combined approach that integrates pharmacologic with non-pharmacologic approaches. This review outlines the scope and impact of hypertension and dyslipidemia in pediatric transplant recipients, with a particular focus on pediatric kidney transplantation given the high burden of chronic kidney disease-associated cardiovascular risk. We also review the current published guidelines for monitoring and managing abnormalities in blood pressure and lipids, highlighting the important role of therapeutic lifestyle changes in concert with antihypertensive and lipid-lowering medications.

Effectiveness and Safety of Statin Therapy in Children: A Real-World Clinical Practice Experience

BACKGROUND

Statin use for hypercholesterolemia in children is predominantly reported from short-term clinical trials. In this study, we assess the efficacy and safety of statin treatment in clinical pediatric practice.

METHODS

Records of all patients who began statin treatment at age <18 years and remained on statins for >6 months from 5 pediatric lipid clinics were reviewed. Information at baseline and from all clinic evaluations after statin initiation was recorded, including lipid measurements, statin drug/dose, safety measures (anthropometry, hepatic enzymes, creatine kinase levels), and symptoms. Lipid changes on statin therapy were assessed from baseline to 6 ± 3 months and from 6 ± 3 months to last follow-up with a mixed-effects model, using piecewise linear splines to describe temporal changes, controlling for repeated measures, sex, and age.

RESULTS

There were 289 patients with median low-density lipoprotein cholesterol (LDL-C) of 5.3 mmol/L (interquartile range [IQR]:4.5-6.5) and mean age of 12.4 ± 2.9 years at statin initiation. Median duration of therapy was 2.7 years (IQR: 1.6-4.5) with 95% on statins at last evaluation. There were significant decreases in total cholesterol, LDL-C, and non-high-density lipoprotein cholesterol (non-HDL-C) from baseline to 6 ± 3 months (P < 0.001) and from 6 ±3 months to last follow-up (P < 0.001). Triglycerides and HDL-C were unchanged but the triglyceride to HDL-C ratio decreased significantly by late follow-up. At final evaluation, median LDL-C had decreased to 3.4 mmol/L (IQR:2.8-4.2). No patient had statins discontinued for safety measures or symptoms.

CONCLUSIONS

In real-world clinical practice, intermediate-term statin treatment is effective and safe in children and adolescents with severe LDL-C elevation.

Review of referral criteria to lipid clinics and outcomes of treatment in four UK centres

BACKGROUND

Little data exist on the referral patterns and effectiveness of lipid clinics.

METHODS

An audit was conducted in four clinics of 100 consecutive referrals each. Data were recorded on referral criteria, cardiovascular disease (CVD) risk factors, drug history, investigations, diagnoses, therapies, results and referrals.

RESULTS

Patients were aged 56 ± 14 years, 47% were male and 87% were primary prevention. Risk factors included smoking (16%), type 2 diabetes (13%) and hypertension (13%). Referrals were made for hypercholesterolaemia (68%), diagnosis of FH (31%), statin intolerance (23%) and hypertriglyceridaemia (23%). Initial total cholesterol (TC) was 7.65 ± 2.64 mmol/L, triglycerides (TG) 2.17 (0.41-76.9 mmol/L) mmol/L, HDL-C 1.53 ± 0.71 mmol/L, LDL-C 4.57 ± 1.66 mmol/L with non-HDL-C 5.90 ± 2.09 mmol/L. Criteria for FH were met in 21% with genetic testing in 13% and lipid cascade testing in 30% of index cases. Triglycerides >20 mmol/L were present in 4%. The diagnosis was changed in 21%: hypercholesterolaemia (7%), mixed hyperlipidaemia (7%) and hypertriglyceridaemia (7%). Hepatic steatosis was identified in 14.5%. Lipoprotein(a) levels >125 nmol/L occurred in 41% in one clinic. Therapy changes included altered statins (40%), addition of a fibrate (11%) or ezetimibe (8%). These reduced TC by 1.92 mmol/L (19%; P = 0.0001), LDL-C 1.07 mmol/L (15%; P = 0.02), non-HDL-C 1.50 mmol/L (16%; P < 0.001), and TG 2.3 (-4 to 38) mmol/L (16%; P < 0.001) with 11% extra achieving TG <5 mmol/L while HDL-C increased by 7% (P = 0.37).

CONCLUSIONS

Lipid clinics have diverse functions including diagnosis of FH, managing severe hypercholesterolaemia, mixed hyperlipidaemia and statin intolerance. Effectiveness criteria of average reductions of 1.5 mmol/L in TC or non-HDL-C, 1 mmol/L in LDL-C and 2 mmol/L in TG would be reasonable for newly referred patients.

Assessment of simvastatin niosomes for pediatric transdermal drug delivery

The prevalence of childhood dyslipidemia increases and is considered as an important risk factor for the incidence of cardiovascular disease in the adulthood. To improve dosing accuracy and facilitate the determination of dosing regimens in function of the body weight, the proposed study aims at preparing transdermal niosomal gels of simvastatin as possible transdermal drug delivery system for pediatric applications. Twelve formulations were prepared to screen the influence of formulation and processing variables on critical niosomal characteristics. Nano-sized niosomes with 0.31 μm number-weighted size displayed highest simvastatin release rate with 8.5% entrapment capacity. The niosomal surface coverage by negative charges was calculated according to Langmuir isotherm with n = 0.42 to suggest that the surface association was site-independent, probably producing surface rearrangements. Hypolipidemic activities after transdermal administration of niosomal gels to rats showed significant reduction in cholesterol and triglyceride levels while increasing plasma high-density lipoproteins concentration. Bioavailability estimation in rats revealed an augmentation in simvastatin bioavailability by 3.35 and 2.9 folds from formulation F3 and F10, respectively, compared with oral drug suspension. Hence, this transdermal simvastatin niosomes not only exhibited remarkable potential to enhance its bioavailability and hypolipidemic activity but also considered a promising pediatric antihyperlipidemic formulation.