Weight gain induced by haloperidol, risperidone and olanzapine after 1 year: findings of a randomized clinical trial in a drug-naïve population.
BACKGROUND
There is little information about weight gain induced by antipsychotics at long-term.


OBJECTIVE
To quantify the weight gain induced by first (haloperidol) and second generation antipsychotics (olanzapine and risperidone) in a cohort of drug-naïve subjects after 1 year of treatment.


METHODS
This is a prospective, randomized clinical trial, including a representative sample of first episode psychotic incident cases from a population area of 555.000 people. The main outcome measures were changes in body weight and body mass index at 3 months and at 12 months. Both a per protocol analysis and an intention to treat analysis were conducted.


RESULTS
A total of 164 drug-naïve patients were included. At 12 months 144 patients were evaluated. Of them, 66% completed the protocol and 34% needed treatment switch. We found statistically significant differences in weight gain at 3 months: 3.8 kg (+/-4.1) for haloperidol, 5.9 kg (+/-5.1) for risperidone and 8.4 kg (+/-5.0) for olanzapine (F=7.045; p=0.002). After 1 year the difference in weight gain had disappeared: 9.7 kg (+/-5.7) for haloperidol, 8.9 kg (+/-8.8) for risperidone and 10.9 kg (+/-7.2) for olanzapine (F=0.817; p=0.445).


CONCLUSIONS
Drug-naïve patients experience an extraordinary weight gain after 1 year of treatment with haloperidol, olanzapine or risperidone. The main difference among these treatments is the pattern of weight gain but not the final amount of weight gain.
Perez-Iglesias
Rocio
R
Department of Psychiatry, Marques de Valdecilla University Hospital, Avda. Valdecilla s/n, 39008, University of Cantabria, Spain.
Crespo-Facorro
Benedicto
B
Martinez-Garcia
Obdulia
O
Ramirez-Bonilla
Maria L
ML
Alvarez-Jimenez
Mario
M
Pelayo-Teran
Jose M
JM
Garcia-Unzueta
Maria T
MT
Amado
Jose A
JA
Vazquez-Barquero
Jose L
JL
D000293:Adolescent; D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001569:Benzodiazepines / Q000009:adverse effects* / Q000627:therapeutic use; D015992:Body Mass Index; D002908:Chronic Disease; D015331:Cohort Studies; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D006220:Haloperidol / Q000009:adverse effects* / Q000627:therapeutic use; D006801:Humans; D008134:Long-Term Care; D008297:Male; D008875:Middle Aged; D000077152:Olanzapine; D018967:Risperidone / Q000009:adverse effects* / Q000627:therapeutic use; D013030:Spain; D016896:Treatment Outcome; D015430:Weight Gain / Q000187:drug effects*
D014150:Antipsychotic Agents; D001569:Benzodiazepines; D006220:Haloperidol; D018967:Risperidone; D000077152:Olanzapine