Cognitive effects of anticonvulsant monotherapy in elderly patients: a placebo-controlled study.

Old age is recognized to be the commonest time in life to develop epilepsy. There is a perception that older patients are more sensitive to the deleterious cognitive effects of antiepileptic drugs (AEDs). Elderly patients (median age 70 years, range 60-88 years) taking anticonvulsant monotherapy (10 carbamazepine [CBZ], 8 sodium valproate [VPA], 5 phenytoin [PHT]) took an extra dose of their usual medication (200mg CBZ, 500mg VPA, 100mg PHT) and matched placebo each for a month in random order. The concentrations of AEDs were higher after 7 and 28 days of active treatment compared with placebo (7 days: CBZ 9.5 vs. 7.8 mg L(-1), p < 0.05; VPA 97 vs. 64 mg L(-1), p < 0.05; PHT 13 vs. 11 mg L(-1), p < 0.05; 28 days: CBZ 9.4 vs. 7.7 mg L(-1); p < 0.01, VPA 85 vs. 60 mg L(-1), p < 0.05; PHT 16 vs. 13 mg L(-1), p < 0.05). Despite these increases in concentration, there were no significant changes in attention, reaction time, finger tapping, memory, side-effect scale or sedation scoring during the active phases compared with placebo phases for the three drugs analysed together and separately. Elderly patients taking standard AEDs as monotherapy did not develop cognitive impairment when the dose was modestly increased within the target range for each drug.

How common is catamenial epilepsy?

Forty women of childbearing age with refractory epilepsy were asked to record their seizures, the first and last days of their menstrual periods, and symptoms of premenstrual tension for 3 consecutive months. By defining catamenial epilepsy as the occurrence of at least 75% of seizures each month in the 10-day time frame, which included the 4 days preceding menstruation and the 6 days after its onset, only 5 women (12.5%) were identified who fulfilled the criterion. Nevertheless, after the study was completed, 31 (78%) of these patients claimed that most of their seizures occurred near the time of and were exacerbated by menstruation. The patients with catamenial epilepsy reported no more symptoms of premenstrual tension than did the rest of the group. Clustering outside the menstrual cycle was noted in 4 other patients. Catamenial epilepsy is an uncommon condition. Patient claims about frequency of seizures in relation to menstruation are not always accurate. A standard definition should be adopted because the diagnosis has implications for management.