Plasma HVA, tardive dyskinesia and psychotic symptoms in long-term drug-free inpatients with schizophrenia

Extrapyramidal syndromes in neuroleptic-treated patients: prevalence, risk factors, and association with tardive dyskinesia

Prevalence and risk factors for extrapyramidal syndromes (EPS) were investigated in a sample of 1,559 patients. The overall prevalence of EPS was 29.4% (N = 458). Among the EPS-diagnosed patients, parkinsonism as assessed by the presence of core parkinsonian symptoms (rigidity, tremor, bradykinesia) was present in 65.9% of patients (N = 302), akathisia in 31.8% (N = 145), and acute dystonia in 2.1% (N = 10). Old age and long-term neuroleptic drug (NL) treatment were significantly associated with EPS in both the univariate and the multivariate analyses, whereas no relationship was observed with average NL daily doses and current NL treatment. EPS was diagnosed in 50.2% of 285 patients with persistent tardive dyskinesia (TD). Distribution of EPS in patients with TD showed that tremor and akathisia were more frequent in peripheral TD cases than in orofacial TD cases. Furthermore, there was a stronger association of NL-induced parkinsonism with peripheral TD than with orofacial TD. This study suggests that the association between EPS and TD may be limited to specific subtypes of TD. Peripheral TD showed a higher association with parkinsonism and with akathisia, suggesting that these symptoms may share a common pathophysiology.

Plasma 3-methoxy-4-hydroxyphenylglycol and homovanillic acid measurements in deficit and nondeficit forms of schizophrenia

BACKGROUND

Discrepancies in the biochemical research on negative symptoms in schizophrenia may be ascribed to the lack of differentiation into primary and secondary negative symptoms. We have used Carpenter's criteria to define the deficit syndrome of schizophrenia as the presence of enduring and primary negative symptoms and measured catecholaminergic parameters in deficit as compared with nondeficit schizophrenics.

METHODS

We have investigated plasma homovanillic acid (pHVA) and 3-methoxy-4-hydroxyphenylglycol (pMHPG) concentrations in 34 DSM-III-R neuroleptic-treated schizophrenic patients who were classified into deficit (n = 14) and nondeficit (n = 20) forms of schizophrenia. All these patients were in a stable clinical and therapeutic status for the preceding 12 months.

RESULTS

The 14 deficit schizophrenic patients had lower plasma levels of pHVA and higher plasma concentrations of pMHPG from 9 AM to 12 AM as compared with the 20 nondeficit schizophrenic patients. The two groups did not differ on any demographic, therapeutic, or clinical variable considered.

CONCLUSIONS

Our data are consistent with the postulated distinct pathophysiological basis for the deficit syndrome of schizophrenia and suggest that opposite alterations in the pHVA or pMHPG levels may reflect specific changes in noradrenergic and dopaminergic functions in these deficit patients.

Prediction of short-term changes in symptom severity by baseline plasma homovanillic acid levels in schizophrenic patients receiving clozapine

The relationship between pretreatment levels of plasma homovanillic acid (pHVA) and the outcome of clozapine treatment was studied in 18 male patients with schizophrenia who were resistant to treatment with conventional neuroleptics. After 6 months of clozapine treatment, 7 patients demonstrated > or = 20% decrease in the Brief Psychiatric Rating Scale (BPRS) (responders), while 11 patients did not (non-responders). Responders and non-responders did not differ with respect to the baseline pHVA level. The BPRS Positive Symptom scores at 6 weeks and 3 months, but not those at baseline and 6 months, following initiation of clozapine treatment negatively correlated with pHVA levels for all patients. The correlations became stronger when only responders were included. No significant correlation between Positive Symptom scores and pHVA levels was observed for non-responders. The BPRS Total and Negative Symptom scores did not correlate with pHVA for all patients, responders or non-responders at any time. The percent decrease in the BPRS Positive Symptom scores from baseline at 6 weeks following clozapine treatment correlated significantly with pHVA levels in responders. These results suggest that pretreatment levels of pHVA can be used to predict relatively short-term changes in the positive symptoms of patients with schizophrenia receiving clozapine treatment, particularly for clozapine responders.

A comparison of plasma homovanillic acid in the deficit and nondeficit subtypes of schizophrenia

Plasma homovanillic acid (pHVA) was measured over a 13 hr-period in 16 DMS-III-R schizophrenic patients, all treated with neuroleptic drugs and in a stable clinical and therapeutic status for the preceeding 12 months. Patients were categorized into deficit (n = 9) and nondeficit (n = 7) forms of schizophrenia according to the Schedule for the Deficit Syndrome (SDS) criteria. As compared to the nondeficit group, deficit patients display significantly lower mean pHVA concentrations from 9 AM to 12 AM and a lack of diurnal variations. None of the demographic, clinical, and therapeutic variables can explain these biological differences. These data suggest a specific biochemical basis for the deficit syndrome of schizophrenia as defined by the SDS criteria, that is, primary, enduring, negative symptoms.

Persistent tardive dyskinesia: demographic and pharmacological risk factors

The demographic, clinical and pharmacological risk factors for persistent tardive dyskinesia (TD) were investigated in a sample of 1745 patients. When simultaneously adjusting for the effects of demographic and pharmacological factors using multivariate logistic regression, female sex and advanced age were positively and significantly associated with increased risk of TD. Interaction between these two variables, investigated by cross-stratification, was significant. Furthermore, high neuroleptic dose and concomitant use of neuroleptic and antiparkinsonian drugs were both significantly associated with increased risk of TD. The results support the view that both vulnerability factors and high neuroleptic doses contribute to the occurrence of TD and further stress the relevance of a conservative use of antipsychotic medication, particularly in older women.