Epilepsy case study

The following case studies are of patients with Alzheimer s disease, Parkinson s disease, depression, bipolar disorder and epilepsy. 

A large number of epidemiology and case-control studies have examined the potential association between oral aluminum exposure and Alzheimer s disease. A number of these studies have been criticized for flawed patient selection, poor comparability of exposed and control groups, poor exposure assessment, poor assessment of health outcomes, and weak statistical correlations (Nieboer et al. 1995 Schupf et al. 1989). Studies conducted by Martyn et al. (1989), McLachlan et al. (1996), and Michel et al. (1990) have found an association between oral exposure to aluminum and an increased risk of Alzheimer s disease. In a survey study conducted by Martyn et al. (1989), the incidence of Alzheimer s disease in individuals under the age of 70 was estimated from computerized tomographic (CT) records. The 1,203 subjects lived in 88 county districts within England and Wales. Data on aluminum concentrations in the municipal water over a 10-year period were obtained from water authorities and water companies. The subjects were classified as having probable Alzheimer s disease, possible Alzheimer s disease, other causes of dementia, or epilepsy. The relative risks of Alzheimer s disease were elevated in the subjects living in districts with aluminum water concentrations of >0.01 mg/L. However, the relative risk exceeded unity only in the subjects with aluminum water concentrations of >0.11 mg/L (relative risk of 1.5, 95% confidence interval of 1.1-2.2). 

Viloxazine has previously been reported to lack epileptogenic properties (SEDA-10, 52). In a review of eight patients (six reported to the UK Committee on Safety of Medicines and two in Japan) it was concluded that there was a possible causal connection with seizures in only two cases, and that such an association was inconsistent with the results of animal studies and with a worldwide review of clinical trials (6). The reviewers concluded that if there is a risk of inducing epilepsy with viloxazine, it is probably only one-tenth that of tricyclic compounds. 

Epilepsy and osteoporosis are very common and frequently overlap. Nevertheless, the prevalence of low bone density appears to be disproportionately higher in patients with epilepsy, and patients with epilepsy have an excessive risk of fractures. A meta-analysis of 94 cohort studies and 72 case-control studies has shown that anticonvulsant treatment is highly associated with fractures (relative risk over 2) (117). Other risk factors were low body weight, weight loss, physical inactivity, consumption of corticosteroids, primary hjrperparathjroidism, type 1 diabetes melhtus, anorexia nervosa, gastrectomy, pernicious anemia, and age over 70 years. 

The effects on bone metabohsm of carbamazepine, valproate, or phenobarbital as monotherapy have been analysed in a case-control study in 118 ambulatory children with epilepsy and corresponding controls (120). Patients taking carbamazepine or phenobarbital had significantly raised alkaline phosphatase and bone and liver isoenzyme activities compared with controls. Although the authors concluded that children who take anticonvulsants may have their bone metabolism affected, this conclusion was based on abnormal values of a surrogate marker for bone disease. 

Nilsson L, Farahmand BY, Persson PG, Thiblin I, Tomson T. Risk factors for sudden unexpected death in epilepsy a case-control study. Lancet 1999 353(9156) 888-93. 

In a pooled analysis of safety data from double-bUnd, placebo-controUed add-on trials of levetiracetam (1-3 g/ day) in adults with refractory partial seizures, adverse events occurring in at least 3% of patients and with at least 3% higher incidence in the active treatment group were tiredness (14 versus 10%), somnolence (15 versus 10%), dizziness (9 versus 4%), and common cold or upper respiratory tract infections (13 versus 7%) (11). The proportions of patients requiring withdrawal of treatment or dosage reduction owing to adverse events were 15% with levetiracetam and 12% with placebo. The efficacy and tolerability of levetiracetam monotherapy in refractory partial seizures have been studied in a double-blind, pla-cebo-controUed study in 286 patients (12). Adverse events that were more common with levetiracetam and that occurred in more than 5% of cases included weakness, infection, and somnolence. Of 181 patients who took levetiracetam, 36 completed the study compared with only 10 of 105 who took placebo. The tolerability and efficacy of levetiracetam, 2 or 4 g/day, as add-on therapy have been studied in 119 patients with refractory epilepsy (13). Somnolence was the most common reason for withdrawal and occurred more often with levetiracetam than placebo, as did weakness. Somnolence was more common with the higher dose, which was not more effective than... 

The effects of stiripentol have been studied in 41 children with severe myoclonic epilepsy in infancy in a randomized, placebo-controlled, add-on trial (2). There were adverse effects in 21 patients taking stiripentol (drowsiness and loss of appetite) compared with five taking placebo, and the adverse effects disappeared when the doses of other antiepileptic drugs were reduced in 12 of the 21 cases. 

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