Cerebral and cerebellar diaschisis following carbamazepine therapy

Capillary microscopy and hemorheology in children during antiepileptic monotherapy with carbamazepine and valproate

The interactions of epilepsy and antiepileptic therapy an one hand and cardiovascular system on the other hand are multiple and complex. Antiepileptic drugs (AEDs) cause alterations of serum lipids and of the fatty acid composition of the membranes. Homocystein, known to induce vascular endothelial damage was found to be elevated in patients on valproate (VPA) and carbamazepine (CBZ) therapy. Marked coronary artherosclerosis and myocardial infarction may already occur in children treated with CBZ. Community based studies corroborated a higher incidence of myocardial infarction, peripheral vascular diseases hypercholesterinemia, left ventricle hypertrophy and stroke in patients with epilepsy. In this context, we wanted to elevate changes of microcirculation related to AEDs commonly prescribed such as VPA and CBZ. Capillary microscopy is a non-invasive technique for measuring the velocity of red blood cells and for determining nutritional blood flow in the capillaries of the skin. It can easily be performed in children. The aim of this study was to look for possible effects an antiepileptic monotherapy with carbamazepine or valproate has on the peripheral microcirculation in epileptic children. We were able to examine 14 children with CBZ and 24 children with VPA, recruited in our neuropediatric Unit. The results were compared to normative values, determined in former analyses of 207 healthy children. We found significant differences in capillary density, tortuous index of the capillaries, capillary diameter and flow rate of erythrocytes for both antiepileptic drugs. Additionally, there were changes in plasma viscosity and the aggregation of erythrocytes. These microcapillary effects could be of special interest in the relationship of a long-term antiepileptic therapy and the development of vascular diseases. We suggest that the influence of AEDs on microcirculation should also be considered in further studies on cardiovascular changes in patients with antiepileptic long-term medication.

Effects of topiramate in patients with cerebellar tremor

PURPOSE

To evaluate the safety and potential beneficial effect of topiramate (TPM) as monotherapy or adjunctive therapy to carbamazepine (CBZ) in patients with cerebellar tremor.

METHODS

Nine patients with cerebellar tremor participated a 4-week, open-label, prospective-controlled trial. TPM was given as monotherapy (n=7 cases), or in combination with CBZ (n=2 cases), at dosages ranging from 25 mg twice daily to 100 mg twice daily. The severity of tremor was assessed clinically on a 0-4 scale, by tremograms, by the Patients Global Impressions Scale, and by a "free writing" task at baseline and after 4 weeks.

RESULTS

TPM was discontinued in four patients due to adverse effects (sedation=2; cognitive impairment=2; increased aggressiveness=2; asthenia=1). During TPM, all patients improved. The mean tremor amplitude, compared with the baseline period, was reduced from 20% to 75%. After TPM, mean clinical scores of postural tremor and kinetic tremor decreased from 2.1+/-0.8 to 0.9+/-0.9 and from 2.1+/-1 to 1.4+/-1 (P<.05), respectively. All patients with head tremor improved. Writing, eating, and drawing were improved with TPM. Four patients chose to keep taking the drug.

CONCLUSIONS

Our study indicates that TPM may be useful for the management of cerebellar tremors. A prospective placebo-controlled trial of TPM in this kind of tremor is warranted. TPM dosages should be titrated slowly to avoid the potential side effects of the drug. The range and the frequency of adverse events might limit the clinical usefulness of TPM.