CATIE Study

Question 1

Phase I

Answer 1

Phase I compared old and new antipsychotics.

CATIE compared four of the newer medications to one another, and to an older medication. Participants in CATIE were followed for 18 months so that investigators could evaluate longer-term patient outcomes. There were more than 1400 participants in the study. CATIE was conducted at many different treatment sites, broadly representative of the real life settings where patients receive their care (pragmatic study). The results from CATIE will be applicable to the wide range of people with schizophrenia in the United States.

In the first phase of CATIE, patients were randomly assigned to one of four newer, “atypical” antipsychotics:

olanzapine
quetiapine
risperidone
ziprasidone

or to the older, “typical” medication:

perphenazine

Overall, the medications were comparably effective but were associated with high rates of discontinuation due to intolerable side effects or failure to adequately control symptoms. One new medication, olanzapine, was slightly better than the other drugs but also was associated with significant weight-gain as a side-effect. Surprisingly, the older, less expensive medication (perphenazine) used in the study generally performed as well as the four newer medications.

Contrary to expectations, movement side effects (rigidity, stiff movements, tremor, and muscle restlessness) primarily associated with the older medications were not seen more frequently with perphenazine than with the newer drugs.

Question 2

Phase II

Answer 2

Phase II sought to provide guidance on which antipsychotic to try next if the first failed (either due to ineffectiveness or intolerability).

Participants who discontinued their first antipsychotic medication because of inadequate management of symptoms were encouraged to enter the efficacy (clozapine) pathway, while participants who discontinued their first treatment because of intolerable side effects were encouraged to enter the tolerability (ziprasidone) pathway.

Clozapine was remarkably effective and was substantially better than all the other atypical medications.

Question 3

Metabolic syndrome

Answer 3

The CATIE study also looked at the risk of metabolic syndrome (MS) using the NCEP (US National Cholesterol Education Program Adult Treatment Panel) criteria which are as follows:

Central obesity: waist circumference 102 cm or 40 inches (male), 88 cm or 36 inches(female)
Dyslipidaemia: TG 1.7 mmol/L (150 mg/dl)
Dyslipidaemia: HDL-C < 40 mg/dL (male), < 50 mg/dL (female)
Blood pressure 130/85 mmHg
Fasting plasma glucose 6.1 mmol/L (110 mg/dl)

The prevalence of MS at baseline in the CATIE group was 40.9%. By gender this was 51.6% in females and 36% in males. Male patients were twice as likely to have MS than matched controls, and female patients were three times as likely compared to matched controls.