Article

Clozapine underutilization and discontinuation in African Americans due to leucopenia.

The Maryland Psychiatric Research Center, Box 21247, Baltimore, MD 21228, USA.
Schizophrenia Bulletin (Impact Factor: 8.61). 10/2007; 33(5):1221-4. DOI: 10.1093/schbul/sbl068
Source: PubMed

ABSTRACT Clozapine use has been notably lower in African American patients than in Caucasians. It has been suggested that lower normal ranges for white blood cell (WBC) counts in African Americans, known as benign ethnic neutropenia, may account partially for the disparity. We examined the rates of leucopenia and agranulocytosis as reasons for discontinuation of clozapine in a sample of 1875 patients with schizophrenia treated in the State of Maryland. Between 1989 and 1999, 5.3% (31/588) of African Americans and 2.4% (31/1287) of Caucasians discontinued clozapine treatment due to leucopenia (chi square = 10.35, df = 1, P = 0.001). No African American patients developed agranulocytosis while 8 Caucasian patients (0.62%) developed this blood dyscrasia. Discontinuations due to leucopenia occurred throughout treatment. Discontinuations due to agranulocytosis occurred primarily in the first 18 weeks (7/8; 87.5% patients with agranulocytosis). It is likely that African Americans had clozapine discontinued unnecessarily due to benign ethnic neutropenia. We concur with recent recommendations to acknowledge differences in WBC values in African Americans and to modify prescribing guidelines or formally acknowledge benign ethnic leucopenia like in other countries in order to facilitate greater use of clozapine in these patients.

1 Bookmark
 · 
144 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The immunomodulatory effects of clozapine (CLZ), antipsychotic drug, were investigated in vivo using female Balb/c mice. The main aim of this study was to evaluate the immunomodulatory effects of CLZ, antipsychotic drug, following daily intraperitoneal injection to female Balb/c mice over a period of 21 days. Mice were divided into five groups, eight animals per group. Group I, served as a control group, received only the vehicle. Groups II-V received a daily intraperitoneal dose of CLZ (1, 5, 10 and 20 mg/kg, respectively) over a period of 21 days. CLZ has shown a significant decrease in the animal body weight, and it showed a significant decrease in the percentage of circulating neutrophils and lymphocytes while circulating monocytes were increased. The immunotoxicity has been also assessed by evaluating spleen cellularity, humoral immune response to a foreign antigen using sheep red blood cells and delayed-type hypersensitivity reaction. The results showed a marked suppression in these responses in CLZ-treated mice compared with the control group. Detectable changes have also been noticed in the histology of the footpad tissue and spleen. Results showed significant immunomuodulatory effects of CLZ when used in Balb/c mice.
    The Journal of pharmacy and pharmacology. 12/2013;
  • [Show abstract] [Hide abstract]
    ABSTRACT: OBJECTIVE The purpose of this study was to examine racial-ethnic differences in use of mental health treatment for a comprehensive range of specific disorders over time. METHODS Data from the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey were used to examine adult outpatient mental health visits to U.S. physicians from 1993 to 2008 (N=754,497). Annual visit prevalence for three racial-ethnic groups was estimated as the number of visits divided by the group's U.S. population size. Visit prevalence ratios (VPRs) were calculated as the minority group's prevalence divided by the non-Hispanic white prevalence. Analyses were stratified by diagnosis, physician type, patient characteristics, and year. RESULTS VPRs for any disorder were .60 (95% confidence interval [CI]=.52-.68) for non-Hispanic blacks and .58 (CI=.50-.67) for Hispanics. Non-Hispanic blacks were treated markedly less frequently than whites for obsessive-compulsive, generalized anxiety, attention-deficit hyperactivity, personality, panic, and nicotine use disorders but more frequently for psychotic disorders. Hispanics were treated far less frequently than whites for bipolar I, impulse control, autism spectrum, personality, obsessive-compulsive, and nicotine use disorders but more frequently for drug use disorders. Racial-ethnic differences in visits to psychiatrists were generally greater than for visits to nonpsychiatrists. Differences declined with increasing patient age and appear to have widened over time. CONCLUSIONS Racial-ethnic differences in receipt of outpatient mental health treatment from U.S. physicians varied substantially by disorder, provider type, and patient age. Most differences were large and did not show improvement over time.
    Psychiatric services (Washington, D.C.) 10/2013; · 2.81 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background Clozapine has shown superior efficacy over other antipsychotics. However, its use is complicated by the development of life-threatening hematologic adverse effects. Objectives This paper reports the incidence of clozapine-induced hematologic toxicity in Saudi Arab patients. Setting King Khalid University Hospital, Riyadh, Saudi Arabia. Methods Medical data of Saudi Arab hospitalized patients receiving clozapine was retrospectively reviewed during the period between August 2009 and August 2012. White blood cell (WBC) counts and differentials were recorded in a specific form to watch for any hematologic toxicity. The hematologic toxicities included in this report are: eosinophilia, thrombocytopenia, lymphocytopenia, and agranulocytosis/neutropenia/leukopenia combined. Main outcome measure Complete WBC count. Results During the study period 147 charts were reviewed. The mean age of patients was 38 ± 11.42 years and 52 % were males. During the study period 61 patients (42 %) developed 82 blood dyscrasias. Sixteen patients (10.9 %) developed agranulocytosis, neutropenia and leukopenia combined, while nineteen patients (12.9 %) developed lymphocytopenia, and seven patients (4.8 %) developed thrombocytopenia. Eosinophilia developed in 40 patients (27.2 %). During the first 18 weeks of therapy with clozapine, 21 (26 %) hematologic side effects were developed. Conclusion The data collected in this study does appear to indicate there may be an increased incidence of blood dyscrasias in Saudi Arabs which warrants further, more detailed, study. It would be of concern to psychiatric clinicians if the case of a genetic predisposition to clozapine-induced blood dyscrasias were proven in the future.
    International Journal of Clinical Pharmacy 06/2014; 36(4). · 1.25 Impact Factor

Full-text (2 Sources)

Download
9 Downloads
Available from
Aug 19, 2014