Lipoprotein metabolism is dependent on apolipoproteins, multifunctional proteins that serve as templates for the assembly of lipoprotein particles, maintain their structure and direct their metabolism through binding to membrane receptors and regulation of enzyme activity. The three principal functions of lipoproteins are contribution to interorgan fuel (triglyceride) distribution (by means of the fuel transport pathway), to the maintenance of the extracellular cholesterol pool (by means of the overflow pathway) and reverse cholesterol transport. The most important clinical application of apolipoprotein measurements in the plasma is in the assessment of cardiovascular risk. Concentrations of apolipoprotein B and apolipoprotein AI (and their ratio) seem to be better markers of cardiovascular risk than conventional markers such as total cholesterol and LDL-cholesterol. Apolipoprotein measurements are also better standardized than the conventional tests. We suggest that measurements of apolipoprotein AI and apolipoprotein B are included as a part of the specialist lipid profile. We also suggest that lipoprotein (a) should be measured as part of the initial assessment of dyslipidaemias because of its consistent association with cardiovascular risk. Genotyping of apolipoprotein E isoforms remains useful in the investigation of mixed dyslipidaemias. Lastly, the role of postprandial metabolism is increasingly recognized in the context of atherogenesis, obesity and diabetes. This requires better markers of chylomicrons, very-low-density lipoproteins and remnant particles. Measurements of apolipoprotein B48 and remnant lipoprotein cholesterol are currently the key tests in this emerging field.

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Summary:Purpose: Treatment with sodium valproate (VPA) may be associated with polycystic ovarian syndrome (PCOS) in some women with epilepsy. By comparing hormone profiles in young adults taking VPA or lamotrigine (LTG) as monotherapy, this study aimed to explore whether a pharmacologic effect of VPA could be responsible for this observation.Methods: Hormone profiles in men and women taking VPA (n ‫ס‬ 40) or LTG (n ‫ס‬ 36) monotherapy for epilepsy were compared. None of the women were receiving hormonal contraception or replacement. Patients gave details of seizure type and frequency, menstrual cycle, and medical and drug history. Body mass index was calculated, and fasting insulin, glucose, cholesterol, triglycerides (TG), high-and low-density lipoproteins, testosterone, dihydroepiandosterone (DHEA), androstenedione, sex hormone-binding globulin (SHBG), free androgen index (FAI), luteinising hormone (LH), folliclestimulating hormone (FSH), and antiepileptic drug (AED) concentrations were measured.Results: There were no differences between treatment groups for both sexes in age and seizure control. Only four obese VPA-treated women were hyperinsulinaemic (p ‫ס‬ 0.05); three with abnormal menstrual cycles; one with raised testosterone. Testosterone (p ‫ס‬ 0.02), FAI (p ‫ס‬ 0.03), and TG (p ‫ס‬ 0.02) levels were higher, however, in women taking the drug. Obese patients of both sexes (p ‫ס‬ 0.01) and VPA-treated men (p ‫ס‬ 0.03) had higher insulin concentrations.Conclusions: VPA therapy may be associated with subclinical elevation in fasting insulin levels. Testosterone and TG levels were higher in VPA-treated women compared with the levels in those taking LTG. However, only a minority of obese females exhibited biochemical characteristics suggestive of PCOS. Biochemical screening may allow women at risk of developing PCOS to avoid VPA. Key Words: Sodium valproate-Lamotrigine-Insulin-Testosterone-Lipids.Sodium valproate (VPA) is a broad-spectrum antiepileptic drug (AED) that has been in use as a first-line agent for >30 years (1). VPA is a branched-chain fatty acid that undergoes similar metabolism to endogenous fatty acids (2,3). Weight gain is a recognised side effect and may be a consequence of mitochondrial inhibition by oxidative metabolites (4-8). Treatment with VPA has been associated with polycystic ovarian syndrome (PCOS) (9-12). This is a heterogeneous condition for which the diagnostic criteria remain a subject of contention (13). It tends to be characterised by ovarian cysts, chronic anovulation, hyperandrogenism, hyperinsulinaemia, and dyslipidaemia (6,(10)(11)(12)(13)(14). Affected women can also have an elevated serum luteinising hormone (LH)/ follicle-stimulating hormone (FSH) ratio, but this is a less sensitive marker (12,15). Although these abnormalities are often linked with obesity, this is not always so.Recent results from studies in Finnish women suggested that ∼60% of patients taking VPA had biochemical and clinical changes associated with PCOS (9,10). As this was not our anecdotal experience...