Relation between serum prolactin levels and antipsychotic response to risperidone in patients with schizophrenia.
Hyperprolactinemia is commonly seen in patients with schizophrenia on risperidone. Dopamine receptor blockade plays a major role in risperidone induced hyperprolactinemia. However, limited studies are available with inconsistent results on antipsychotic response to risperidone and prolactin elevation. Therefore, we aimed to study the change in serum prolactin levels and response to risperidone and to test the association between DRD2 genetic variants and prolactin levels in schizophrenic patients treated with risperidone.



A prospective study comprising of 102 patients with schizophrenia were recruited. Prolactin levels and Positive and Negative Syndrome Scale (PANSS) score were recorded at baseline and after four weeks of risperidone treatment. Prolactin concentrations were measured by standard method Advia-Centaur® Chemiluminescence immuno assay method. Taq1A DRD2 genotyping was performed by qRT-PCR.



The mean±SD prolactin levels (ng/ml) were increased after four weeks of treatment in both responders (males 21.66±15.15 to 41.63±18.73; p<0.01 females 51.92±40.89 to 122.35±52.16; p<0.01) and non-responders group (males 23.89±14.85 to 37.45±13.5; p<0.01 females 39.25±26.94 to 91.13±54.31; p<0.01). Patients with increased prolactin concentration were 4.6 fold higher in responders (OR 4.60; 95%CI 1.376-15.389; p-value 0.01) compared to non-responders. Ninety-six patients were genotyped for Taq1A DRD2 gene (AA=9, AG=46, GG=41) and found no association (p=0.6) between genetic variants and response to risperidone.



Patients were showing more than 20% increase in prolactin levels had a better chance of responding to risperidone therapy. Taq1A DRD2 gene did not show any association with prolactin elevation and response to risperidone.
Department of Pharmacology, JIPMER, Puducherry 605006, India. Electronic address: Charan.raj002@gmail.com.
Alladi
A
Charan
Department of Pharmacology, JIPMER, Puducherry 605006, India. Electronic address: dgshewade@gmail.com.
Deepak Gopal
DG
Shewade
Department of Psychiatry, JIPMER, Puducherry 605006, India. Electronic address: Ravi.psych@gmail.com.
Ravi Philip
RP
Rajkumar
Department Of Clinical Pharmacology, JIPMER, Puducherry 605006, India. Electronic address: Adithan50@gmail.com.
Adithan
A
Chandrasekaran
D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D004351:Drug Resistance; D005260:Female; D005838:Genotype; D006801:Humans; D006966:Hyperprolactinemia / Q000139:chemically induced* / Q000523:psychology; D008297:Male; D008875:Middle Aged; D011388:Prolactin / Q000097:blood*; D011446:Prospective Studies; D017448:Receptors, Dopamine D2 / Q000097:blood; D018967:Risperidone / Q000009:adverse effects / Q000627:therapeutic use*; D012559:Schizophrenia / Q000097:blood* / Q000188:drug therapy / Q000235:genetics; D019914:Taq Polymerase / Q000097:blood; D016896:Treatment Outcome
D014150:Antipsychotic Agents; C581293:DRD2 protein, human; D017448:Receptors, Dopamine D2; D011388:Prolactin; D019914:Taq Polymerase; D018967:Risperidone
DRD2 Taq1A polymorphism; Dopamine receptor (DRD2); PANSS (Positive and Negative Syndrome Scale); Prolactin; Schizophrenia