Treatmant of Delirium with risperidone and olanzapine
ILIAS S., MANTZARIS M., ANTONATOS S., XILOURIS G., DOUBOU D.

Purpose: To examine the efficacy of risperidone and olanzapine in patients suffering from Delirium. Delirium occurs in 14% to 56% of elderly hospitalized patients and it is associated with high mortality rates (10%-65%), longer and costlier hospitalization and also increased non-hospitalized care and rehabilitation.

Methods: We studied 40 patients with Delirium. 20 of them received risperidone and 20 of them received olanzapine. Patients with a history of dementia or psychosis or alcohol withdrawal syndrome (Delirium Tremens) were excluded from the study. All subjects were monitored by means of the Delirium Rating Scale (DRS) and the Mini Mental State Examination (M.M.S.E.). All patients were evaluated before starting treatment and on the day of the maximal response to both antipsychotics.

All patients were monitored daily during the first days regarding the therapeutic result, their vital signs and possible adverse effects. The initial dose of risperidone was 0.5 mg twice daily on Day 1 with increase of daily dosage from 0.5 to 1 mg, if required to control their symptomatology. The initial dose of olanzapine was 5 mg once daily on Day 1 with increase of the daily dosage from 0.25 mg to 5 mg, if required. A statistical quality analysis with chi-square was performed.

Results: The group of patients treated with risperidone consisted of 11 males and 9 females ranging from 18 to 87 years of age. 14 (70%) of our sample were elderly patients >65 years old. The group of patients treated with olanzapine consisted of 12 males and 8 females from 22 to 85 years of age. 15 (75%) of our sample were elderly patients. No statistical significant difference was found between the 2 groups as far as the percentage of elderly patients is concerned. Premature discontinuation from the study in the group of risperidone due to adverse effects or lack of efficacy occurred in 4 patients (20%), 3 of them were elderly patients. In the group of olanzapine the rate of discontinuation was 5 patients (25%), 3 elderly patients.

Average pretreatment DRS scores in the group of risperidone were 18.25.6 and in the group of olanzapine 19.56.3. 14 (70%) patients from the group of risperidone and 13 (65%) patients from the group of olanzapine showed significant or moderate improvement. No statistical significant difference was found between the 2 antipsychotics in terms of their efficacy, p=0.736 chi-square. Moderate improvement was defined as 21% to 50% reduction of the DRS score and significant as a greater than 50% reduction of the pretreatment DRS score.

75% of the patients included in the group of risperidone responded to the dose of 1 mg to 2 mg daily. 73% of the patients included in the group of olanzapine were improved with 5 mg. The rest of the patients needed higher doses. The highest dose of risperidone was 4 mg daily divided into 2 doses and the highest dose of olanzapine was 10 mg once daily administered at night.

The average duration of risperidone treatment was 7.84.8 days (3 to 15 days) and the maximal response was seen at 6.55.4 days. The average duration of olanzapine treatment was 8.45.1 days (3 to 21 days) and the maximal response was seen at 7.55.2 days. 7 (35%) patients treated with risperidone and 6 (30%) patients treated with olanzapine developed at least one adverse effect. No statistical significant difference was found between the 2 groups in terms of adverse effects. The most common adverse effects in the patients of the risperidone treatment group were hypotension, sedation and EPS. The most common adverse effects in the patients of the olanzapine treatment group were sedation, somnolence and constipation. The guideline given by the National Organization for Medicines (EOF) in 2004 requiring special attention on prescribing risperidone and olanzapine to elderly patients with dementia still applies since controlled studies with placebo have shown adverse effects from the cerebral vessels (stroke, TIAs).

Conclusions: Risperidone and olanzapine are effective in treating Delirium. There are a few studies in the bibliography on this subject. More controlled studies are required in order to confirm their efficacy.

Key words: Delirium, risperidone, olanzapine, treatment.