Is there an interrelationship between the effects of antipsychotics on psychopathology and on
metabolism?
Sammanfattning
Background: Increased body weight and hyperlipidemia caused by antipsychotics may be
associated with improved antipsychotic efficacy in schizophrenia. If this association has a causal
interrelationship via a genuine pathophysiological mechanism, then body weight loss in
antipsychotic-treated patients would be accompanied by worsened psychopathology. This could have
clinical implications. Aim: To explore whether the decreased body weight in these patients is
associated with a worsened psychopathology. Methods: In our previously published study, a 16
week treatment period with add-on orlistat (but not placebo) resulted in body weight loss in male (but
not female) clozapine- or olanzapine-treated overweight or obese patients. In the current study, we
investigated whether body weight loss in those male patients could worsen psychosis. Changes in
the Positive and Negative Syndrome Scale (PANSS) scores within groups and body weight changes
and lipid profiles over the treatment period were analysed by the paired samples t-test. Between-
group comparisons were analysed by the independent samples t-test. Results: Over the treatment
period body weight decreased by 2.56 ± 3.25 kg from initial 106.02 ± 12.61kg (p = 0.04) for the orlistat
group, with no statistically significant changes for the placebo group. Lipid levels did not change in
either group. The orlistat-induced weight decrease was not associated with worsening in the PANSS
scores. Conclusions: Weight loss was not associated with a worsening of psychosis. The
interrelationship between the antipsychotic-induced weigh gain and improved schizophrenia
psychopathology observed in earlier studies appears to be indirect. Orlistat treatment in our study
did not worsen psychopathology in this population.