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Spontaneous movement disorders in antipsychotic-naive patients with first-episode psychoses: a systematic review

Published online by Cambridge University Press:  12 November 2008

S. Pappa  and
P. Dazzan
S. Pappa*
Affiliation:
Institute of Psychiatry, Division of Psychological Medicine, King's CollegeLondon, UK
P. Dazzan
Affiliation:
Institute of Psychiatry, Division of Psychological Medicine, King's CollegeLondon, UK
*
*Address for correspondence: S. Pappa, M.D., Ph.D., Consultant Psychiatrist and Honorary Research Associate, Department of Psychiatry, PO 63, Institute of Psychiatry, De Crespigny Park, London SE5 8AF, UK. (Email: sofia.pappa@iop.kcl.ac.uk)
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Abstract

Background

Spontaneous movement disorders (SMDs), such as spontaneous dyskinesia and parkinsonism, have been described in patients with schizophrenia who have never been treated with antipsychotic medication. Their presence has been documented extensively in chronic schizophrenia but not at the time of illness onset.

Method

We performed a systematic review of studies investigating spontaneous abnormal movements elicited on clinical examination in antipsychotic-naive patients with first-episode psychosis.

Results

We identified a total of 13 studies. Findings suggest a spontaneous dyskinesia median rate of 9% and a spontaneous parkinsonism median rate of 17%. Information on akathisia and dystonia was limited. The presence of SMDs may be associated with negative symptoms and cognitive dysfunction.

Conclusions

These findings support the notion that spontaneous abnormal movements are part of a neurodysfunction intrinsic to the pathogenesis of schizophrenia. Future studies should further investigate the role of basal ganglia and extrapyramidal pathways in the pathophysiology of psychosis, with particular attention to treatment implications.

Keywords

Antipsychotic-naivefirst-episode psychosisspontaneous dyskinesiaspontaneous movement disorders
Type
Review Article
Information
Psychological Medicine , Volume 39 , Issue 7 , July 2009 , pp. 1065 - 1076
Copyright
Copyright © 2008 Cambridge University Press

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References

Andreasen, NC, Nopoulos, P, O'Leary, DS, Miller, DD, Wassink, T, Flaum, M (1999). Defining the phenotype of schizophrenia: cognitive dysmetria and its neural mechanisms. Biological Psychiatry 46, 908–920.CrossRefGoogle ScholarPubMed
Andreasen, NC, Paradiso, S, O'Leary, DS (1998). ‘Cognitive dysmetria’ as an integrative theory of schizophrenia: a dysfunction in cortical-subcortical-cerebellar circuitry? Schizophrenia Bulletin 24, 203–218.CrossRefGoogle ScholarPubMed
Baldessarini, RJ (1988). A summary of current knowledge of tardive dyskinesia. Encephale 14, 263–268.Google ScholarPubMed
Barnes, TR (1989). A rating scale for drug-induced akathisia. British Journal of Psychiatry 154, 672–676.CrossRefGoogle ScholarPubMed
Blowers, AJ, Borison, RL, Blowers, CM, Bicknell, DJ (1981). Abnormal involuntary movements in the elderly. British Journal of Psychiatry 139, 363–364.CrossRefGoogle ScholarPubMed
Bocti, C, Black, DN, Waddington, JL (2003). Dyskinesia in patients with schizophrenia never treated with antipsychotics: conceptual and pathophysiological implications. In Mental and Behavioral Dysfunction in Movement Disorders (ed. Bédard, M. A., Agid, Y., Chouinard, S., Fahn, S., Korczyn, A. and Lesperance, P.), pp. 489–498. Humana Press: Totowa.CrossRefGoogle Scholar
Bourgeois, M, Boueilh, P, Tignol, J (1980 a). Spontaneous dyskinesia in the elderly and tardive dyskinesia of neuroleptics. A survey among 270 patients. Encephale 6, 37–39.Google ScholarPubMed
Bourgeois, M, Bouilh, P, Tignol, J, Yesavage, J (1980 b). Spontaneous dyskinesias vs neuroleptic-induced dyskinesias in 270 elderly subjects. Journal of Nervous and Mental Disease 168, 177–178.CrossRefGoogle ScholarPubMed
Brown, KW, White, T (1992). The influence of topography on the cognitive and psychopathological effects of tardive dyskinesia. American Journal of Psychiatry 149, 1385–1389.Google ScholarPubMed
Caligiuri, MP, Bracha, HS, Lohr, JB (1989). Asymmetry of neuroleptic-induced rigidity: development of quantitative methods and clinical correlates. Psychiatry Research 30, 275–284.CrossRefGoogle ScholarPubMed
Caligiuri, MP, Lohr, JB (1997). Instrumental motor predictors of neuroleptic-induced parkinsonism in newly medicated schizophrenia patients. Journal of Neuropsychiatry and Clinical Neurosciences 9, 562–567.Google ScholarPubMed
Caligiuri, MP, Lohr, JB, Jeste, DV (1993). Parkinsonism in neuroleptic-naive schizophrenic patients. American Journal of Psychiatry 150, 1343–1348.Google ScholarPubMed
Casey, DE (1985). Spontaneous and tardive dyskinesias: clinical and laboratory studies. Journal of Clinical Psychiatry 46, 42–47.Google ScholarPubMed
Chakos, MH, Alvir, JM, Woerner, MG, Koreen, A, Geisler, S, Mayerhoff, D, Sobel, S, Kane, JM, Borenstein, M, Lieberman, JA (1996). Incidence and correlates of tardive dyskinesia in first episode of schizophrenia. Archives of General Psychiatry 53, 313–319.CrossRefGoogle ScholarPubMed
Chakos, MH, Mayerhoff, DI, Loebel, AD, Alvir, JM, Lieberman, JA (1992). Incidence and correlates of acute extrapyramidal symptoms in first episode of schizophrenia. Psychopharmacology Bulletin 28, 81–86.Google ScholarPubMed
Chatterjee, A, Chakos, M, Koreen, A, Geisler, S, Sheitman, B, Woerner, M, Kane, JM, Alvir, J, Lieberman, JA (1995). Prevalence and clinical correlates of extrapyramidal signs and spontaneous dyskinesia in never-medicated schizophrenic patients. American Journal of Psychiatry 152, 1724–1729.Google ScholarPubMed
Chong, SA, Subramaniam, M, Verma, S (2005). Spontaneous parkinsonism in antipsychotic-naive patients with first-episode psychosis. Canadian Journal of Psychiatry 50, 429–431.CrossRefGoogle ScholarPubMed
Chorfi, M, Moussaoui, D (1985). Never treated schizophrenic patients have no abnormal movements such as tardive dyskinesia. Encephale 11, 263–265.Google ScholarPubMed
Chouinard, G, Ross-Chouinard, A, Annable, L, Jones, BD (1980). The Extrapyramidal Symptom Rating Scale. Canadian Journal of Neurological Sciences 7, 233.Google Scholar
Correll, CU, Leucht, S, Kane, JM (2004). Lower risk for tardive dyskinesia associated with second-generation antipsychotics: a systematic review of 1-year studies. American Journal of Psychiatry 161, 414–425.CrossRefGoogle ScholarPubMed
Cortese, L, Caligiuri, MP, Malla, AK, Manchanda, R, Takhar, J, Haricharan, R (2005). Relationship of neuromotor disturbances to psychosis symptoms in first-episode neuroleptic-naive schizophrenia patients. Schizophrenia Research 75, 65–75.CrossRefGoogle ScholarPubMed
Crane, GE (1978). Parkinsonism and tardive dyskinesia. American Journal of Psychiatry 135, 619–620.CrossRefGoogle ScholarPubMed
Crow, TJ (1985). The two-syndrome concept: origins and current status. Schizophrenia Bulletin 11, 471–486.CrossRefGoogle ScholarPubMed
Crow, TJ, Cross, AJ, Johnstone, EC, Owen, F, Owens, DG, Waddington, JL (1982). Abnormal involuntary movements in schizophrenia: are they related to the disease process or its treatment? Are they associated with changes in dopamine receptors? Journal of Clinical Psychopharmacology 2, 336–340.CrossRefGoogle ScholarPubMed
Csernansky, JG, Murphy, GM, Faustman, WO (1991). Limbic/mesolimbic connections and the pathogenesis of schizophrenia. Biological Psychiatry 30, 383–400.CrossRefGoogle ScholarPubMed
Dazzan, P, Morgan, KD, Chitnis, X, Suckling, J, Morgan, C, Fearon, P, McGuire, PK, Jones, PB, Leff, J, Murray, RM (2006). The structural brain correlates of neurological soft signs in healthy individuals. Cerebral Cortex 16, 1225–1231.CrossRefGoogle ScholarPubMed
Dazzan, P, Morgan, KD, Orr, KG, Hutchinson, G, Chitnis, X, Suckling, J, Fearon, P, Salvo, J, McGuire, PK, Mallett, RM, Jones, PB, Leff, J, Murray, RM (2004). The structural brain correlates of neurological soft signs in AESOP first-episode psychoses study. Brain 127, 143–153.CrossRefGoogle ScholarPubMed
Draganski, B, Kherif, F, Klöppel, S, Cook, PA, Alexander, DC, Parker, GJ, Deichmann, R, Ashburner, J, Frackowiak, RS (2008). Evidence for segregated and integrative connectivity patterns in the human basal ganglia. Journal of Neuroscience 28, 7143–7152.CrossRefGoogle ScholarPubMed
Eastham, JH, Lacro, HP, Jeste, DV (1996). Ethnicity and movement disorders. Mount Sinai Journal of Medicine 63, 314–319.Google ScholarPubMed
Emsley, R, Turner, HJ, Oosthuizen, PP, Carr, J (2005). Neurological abnormalities in first-episode schizophrenia: temporal stability and clinical and outcome correlates. Schizophrenia Research 75, 35–44.CrossRefGoogle ScholarPubMed
Fenn, DS, Moussaoui, D, Hoffman, WF, Kadri, N, Bentounssi, B, Tilane, A, Khomeis, M, Casey, DE (1996). Movements in never-medicated schizophrenics: a preliminary study. Psychopharmacology 123, 206–210.CrossRefGoogle ScholarPubMed
Fenton, WS (2000). Prevalence of spontaneous dyskinesia in schizophrenia. Journal of Clinical Psychiatry 61 (Suppl. 4), 10–14.Google ScholarPubMed
Fenton, WS, Wyatt, RJ, McGlashan, TH (1994). Risk factors for spontaneous dyskinesia in schizophrenia. Archives of General Psychiatry 51, 643–650.CrossRefGoogle ScholarPubMed
Friedman, JH (2004). Historical perspective on movement disorders. Journal of Clinical Psychiatry 65 (Suppl. 9), 3–8.Google ScholarPubMed
Gerlach, J, Casey, DE (1988). Tardive dyskinesia. Acta Psychiatrica Scandinavica 77, 369–378.CrossRefGoogle ScholarPubMed
Gerlach, J, Korsgaard, S, Clemmesen, P, Lauersen, AM, Magelund, G, Noring, U, Povlsen, UJ, Bech, P, Casey, DE (1993). The St. Hans Rating Scale for extrapyramidal syndromes: reliability and validity. Acta Psychiatrica Scandinavica 87, 244–52.CrossRefGoogle ScholarPubMed
Gervin, M, Browne, S, Lane, A, Clarke, M, Waddington, JL, Larkin, C, O'Callaghan, E (1998). Spontaneous abnormal involuntary movements in first-episode schizophrenia and schizophreniform disorder: baseline rate in a group of patients from an Irish catchment area. American Journal of Psychiatry 155, 1202–1206.CrossRefGoogle Scholar
Graybiel, AM (1997). The basal ganglia and cognitive pattern generators. Schizophrenia Bulletin 23, 459–469.CrossRefGoogle ScholarPubMed
Green, AI, Lieberman, JA, Hamer, RM, Glick, ID, Gur, RE, Kahn, RS, McEvoy, JP, Perkins, DO, Rothschild, AJ, Sharma, T, Tohen, MF, Woolson, S, Zipursky, RB; the HGDH Study Group (2006). Olanzapine and haloperidol in first episode psychosis: two-year data. Schizophrenia Research 86, 234–243.CrossRefGoogle ScholarPubMed
Gur, RE, Gur, RC, Skolnick, BE, Caroff, S, Obrist, WD, Resnick, S, Reivich, M (1985). Brain function in psychiatric disorders. III. Regional cerebral blood flow in unmedicated schizophrenics. Archives of General Psychiatry 42, 329–334.CrossRefGoogle ScholarPubMed
Günther, W, Petsch, R, Steinberg, R, Moser, E, Streck, P, Heller, H, Kurtz, G, Hippius, H (1991). Brain dysfunction during motor activation and corpus callosum alterations in schizophrenia measured by cerebral blood flow and magnetic resonance imaging. Biological Psychiatry 29, 535–555.CrossRefGoogle ScholarPubMed
Hernan Silva, I, Jerez, CS, Ruiz, TA, Seguel, LM, Court, LJ, Labarca, BR (1994). Lack of involuntary abnormal movements in untreated schizophrenic patients. Actas Luso Espanolas de Neurologia, Psiquiatria y Ciencias Afines 22, 200–202.Google ScholarPubMed
Hoffman, W, Kadri, N, Fenn, D, Tilane, A, Green, C, Lakloumi, M, Bousaid, F, Bentounssi, B, Moussaoui, D, Casey, D (1996). Choreo-athetoid movements occur spontaneously in never-medicated patients with schizophrenia. European Neuropharmacology 6, (Suppl. 3), 223.CrossRefGoogle Scholar
Honer, WG, Kopala, LC, Rabinowitz, J (2005). Extrapyramidal symptoms and signs in first-episode, antipsychotic exposed and non-exposed patients with schizophrenia or related psychotic illness. Journal of Psychopharmacology 19, 277–285.CrossRefGoogle ScholarPubMed
Hunter, RH, Joy, CB, Kennedy, E, Gilbody, SM, Song, F (2003). Risperidone versus typical antipsychotic medication for schizophrenia. Cochrane Database of Systematic Reviews. Issue no. 2. Art. no. CD000440.CrossRefGoogle Scholar
Jager, A (2000). Abnormal movements in first episode psychosis. Australian Psychiatry 8, 38–41.CrossRefGoogle Scholar
Kane, JM (2004). Tardive dyskinesia rates with atypical antipsychotics in adults: prevalence and incidence. Journal of Clinical Psychiatry 65 (Suppl. 9), 16–20.Google ScholarPubMed
Kane, JM, Smith, JM (1982). Tardive dyskinesia: prevalence and risk factors, 1959 to 1979. Archives of General Psychiatry 39, 473–481.CrossRefGoogle ScholarPubMed
Kane, JM, Weinhold, P, Kinon, B, Wegner, J, Leader, M (1982). Prevalence of abnormal involuntary movements (‘spontaneous dyskinesias’) in the normal elderly. Psychopharmacology 77, 105–108.CrossRefGoogle ScholarPubMed
Kane, JM, Woerner, M, Lieberman, J (1988). Epidemiological aspects of tardive dyskinesia. Encephale 14, 191–194.Google ScholarPubMed
Keshavan, MS, Rosenberg, D, Sweeney, JA, Pettegrew, JW (1998). Decreased caudate volume in neuroleptic-naive psychotic patients. American Journal of Psychiatry 155, 774–778.Google ScholarPubMed
Keshavan, MS, Sanders, RD, Sweeney, JA, Diwadkar, VA, Goldstein, G, Pettegrew, JW, Schooler, NR (2003). Diagnostic specificity and neuroanatomical validity of neurological abnormalities in first-episode psychoses. American Journal of Psychiatry 160, 1298–1304.CrossRefGoogle ScholarPubMed
Klawans, HL, Barr, A (1982). Prevalence of spontaneous lingual-facial-buccal dyskinesias in the elderly. Neurology 32, 558–559.CrossRefGoogle ScholarPubMed
Kopala, LC, Good, KP, Honer, WG (1997). Extrapyramidal signs and clinical symptoms in first-episode schizophrenia: response to low-dose risperidone. Journal of Clinical Psychopharmacology 17, 308–313.CrossRefGoogle ScholarPubMed
Kopala, LC, Good, KP, Milliken, H, Buiteman, C, Woodley, H, Rui, Q, Whitehorn, D, Love, L, Balshaw, R, Kiss, I, Honer, WG (2006). Treatment of a first episode of psychotic illness with quetiapine: an analysis of 2 year outcomes. Schizophrenia Research 81, 29–39.CrossRefGoogle ScholarPubMed
Kraepelin, E (1919). Dementia Praecox. Livingstone: Edinburgh.Google Scholar
Lawrie, SM, Byrne, M, Miller, P, Hodges, A, Clafferty, RA, Cunningham Owens, DG, Johnstone, EC (2001). Neurodevelopmental indices and the development of psychotic symptoms in subjects at high risk of schizophrenia. British Journal of Psychiatry 178, 524–530.CrossRefGoogle ScholarPubMed
Liddle, PF, Lane, CJ, Ngan, ET (2000). Immediate effects of risperidone on cortico-striato-thalamic loops and the hippocampus. British Journal of Psychiatry, 177, 402–407.CrossRefGoogle ScholarPubMed
McCreadie, RG, Latha, S, Thara, R, Padmavathi, R, Ayankaran, JR (1997). Poor memory, negative symptoms and abnormal movements in never-treated Indian patients with schizophrenia. British Journal of Psychiatry 171, 360–363.CrossRefGoogle ScholarPubMed
McCreadie, RG, Ohaeri, JU (1994). Movement disorder in never and minimally treated Nigerian schizophrenic patients. British Journal of Psychiatry 164, 184–189.CrossRefGoogle ScholarPubMed
McCreadie, RG, Srinivasan, TN, Padmavati, R, Thara, R (2005). Extrapyramidal symptoms in unmedicated schizophrenia. Journal of Psychiatric Research 39, 261–266.CrossRefGoogle ScholarPubMed
McCreadie, RG, Thara, R, Kamath, S, Padmavathy, R, Latha, S, Mathrubootham, N, Menon, MS (1996). Abnormal movements in never-medicated Indian patients with schizophrenia. British Journal of Psychiatry 168, 221–226.CrossRefGoogle ScholarPubMed
Mehler-Wex, C, Riederer, P, Gerlach, M (2006). Dopaminergic dysbalance in distinct basal ganglia neurocircuits: implications for the pathophysiology of Parkinson's disease, schizophrenia and attention deficit hyperactivity disorder. Neurotoxicity Research 10, 167–179.CrossRefGoogle ScholarPubMed
Menon, V, Anagnoson, RT, Glover, GH, Pfefferbaum, A (2001). Functional magnetic resonance imaging evidence for disrupted basal ganglia function in schizophrenia. American Journal of Psychiatry 158, 646–649.CrossRefGoogle ScholarPubMed
Montastruc, JL, Llau, ME, Rascol, O, Senard, JM (1994). Drug-induced parkinsonism: a review. Fundamental and Clinical Pharmacology 8, 293–306.CrossRefGoogle ScholarPubMed
Müller, JL, Deuticke, C, Putzhammer, A, Röder, CH, Hajak, G, Winkler, J (2003). Schizophrenia and Parkinson's disease lead to equal motor-related changes in cortical and subcortical brain activation: an fMRI fingertapping study. Psychiatry and Clinical Neurosciences 57, 562–568.Google ScholarPubMed
Owens, DG (1999). A Guide to the Extrapyramidal Side-effects of Antipsychotic Drugs. Cambridge University Press: Cambridge.CrossRefGoogle Scholar
Owens, DG, Johnstone, EC, Frith, CD (1982). Spontaneous involuntary disorders of movement: their prevalence, severity, and distribution in chronic schizophrenics with and without treatment with neuroleptics. Archives of General Psychiatry 39, 452–461.CrossRefGoogle ScholarPubMed
Peralta, V, Cuesta, MJ (1999). Negative parkinsonian, depressive and catatonic symptoms in schizophrenia: a conflict of paradigms revisited. Schizophrenia Research 40, 245–253.CrossRefGoogle ScholarPubMed
Peralta, V, Cuesta, MJ, Martinez-Larrea, A, Serrano, JF (2000). Differentiating primary from secondary negative symptoms in schizophrenia: a study of neuroleptic-naive patients before and after treatment. American Journal of Psychiatry 157, 1461–1466.CrossRefGoogle ScholarPubMed
Puri, BK, Barnes, TR, Chapman, MJ, Hutton, SB, Joyce, EM (1999). Spontaneous dyskinesia in first episode schizophrenia. Journal of Neurology, Neurosurgery and Psychiatry 66, 76–78.CrossRefGoogle ScholarPubMed
Rogers, D (1985). The motor disorders of severe psychiatric illness: a conflict of paradigms. British Journal of Psychiatry 147, 221–232.CrossRefGoogle ScholarPubMed
Sandyk, R, Kay, SR (1991 a). Drug-induced parkinsonism: relationship to age at onset of schizophrenia. Functional Neurology 6, 151–157.Google ScholarPubMed
Sandyk, R, Kay, SR (1991 b). The relationship of tardive dyskinesia to positive schizophrenia. International Journal of Neuroscience 56, 107–139.CrossRefGoogle ScholarPubMed
Sandyk, R, Kay, SR (1992). ‘Positive’ and ‘negative’ movement disorders in schizophrenia. International Journal of Neuroscience 66, 143–151.Google ScholarPubMed
Schooler, NR, Kane, JM (1982). Research diagnoses for tardive dyskinesia. Archives of General Psychiatry 39, 486–487.Google ScholarPubMed
Schooler, N, Rabinowitz, J, Davidson, M, Emsley, R, Harvey, PD, Kopala, L, McGorry, PD, Van Hove, I, Eerdekens, M, Swyzen, W, De Smedt, G; Early Psychosis global Working Group (2006). Risperidone and haloperidol in first-episode psychosis: a long-term randomized trial. Schizophrenia Research 162, 947–953.Google Scholar
Schröder, J, Niethammer, R, Geider, FJ, Reitz, C, Binkert, M, Jauss, M, Sauer, H (1991). Neurological soft signs in schizophrenia. Schizophrenia Research 6, 25–30.CrossRefGoogle ScholarPubMed
Simpson, GM, Angus, JW (1970). A rating scale for extrapyramidal side effects. Acta Psychiatrica Scandinavica (Suppl.) 212, S11–S19.CrossRefGoogle ScholarPubMed
Simpson, GM, Lee, JH, Zoubok, B, Gardos, G (1979). A rating scale for tardive dyskinesia. Psychopharmacology 64, 171–179.CrossRefGoogle ScholarPubMed
Srinivasan, TN, Thara, R, Padmavathi, R, McCreadie, RG (2001). Relationship of extrapyramidal symptoms to age at onset and drug treatment in middle-aged and elderly schizophrenic patients. Schizophrenia Research 47, 69–75.CrossRefGoogle ScholarPubMed
Stahl, SM (2000). Essential Psychopharmacology, 2nd edn. Cambridge University Press: New York.Google Scholar
Tenback, DE, Van Harten, PN, Slooff, CJ, Van Os, J (2006). Evidence that early extrapyramidal symptoms predict later tardive dyskinesia: a prospective analysis of 10,000 patients in the European Schizophrenia Outpatient Health Outcomes (SOHO) study. American Journal of Psychiatry 163, 1438–1440.CrossRefGoogle ScholarPubMed
Tomer, R, Mintz, M, Kempler, S, Sigal, M (1987). Lateralized neuroleptic-induced side effects are associated with asymmetric visual evoked potentials. Psychiatry Research 22, 311–318.CrossRefGoogle ScholarPubMed
Torrey, EF (2002). Studies of individuals with schizophrenia never treated with antipsychotic medications: a review. Schizophrenia Research 58, 101–115.CrossRefGoogle ScholarPubMed
Turner, T (1989). Rich and mad in Victorian England. Psychological Medicine 19, 29–44.CrossRefGoogle ScholarPubMed
Utter, A, Basso, M (2008). The basal ganglia: an overview of circuits and function. Neuroscience and Biobehavioral Reviews 32, 333–342.CrossRefGoogle ScholarPubMed
Venkatasubramanian, G, Latha, V, Gangadhar, BN, Janakiramaiah, N, Subbakrishna, DK, Jayakumar, PN, Keshavan, MS (2003). Neurological soft signs in never-treated schizophrenia. Acta Psychiatrica Scandinavica 108, 144–146.CrossRefGoogle ScholarPubMed
Waddington, JL, O'Callaghan, E, Larkin, C, Kinsella, A (1993). Cognitive dysfunction in schizophrenia: organic vulnerability factor or state marker for tardive dyskinesia? Brain and Cognition 23, 56–70.CrossRefGoogle ScholarPubMed
Waddington, JL, Youssef, HA (1985). Late onset involuntary movements in chronic schizophrenia: age-related vulnerability to ‘tardive’ dyskinesia independent of extent of neuroleptic medication. Irish Medical Journal 78, 143–146.Google ScholarPubMed
Waddington, JL, Youssef, HA (1990). The lifetime outcome and involuntary movements of schizophrenia never treated with neuroleptic drugs. Four rare cases in Ireland. British Journal of Psychiatry 156, 106–108.CrossRefGoogle ScholarPubMed
Waddington, JL, Youssef, HA, Dolphin, C, Kinsella, A (1987). Cognitive dysfunction, negative symptoms, and tardive dyskinesia in schizophrenia. Their association in relation to topography of involuntary movements and criterion of their abnormality. Archives of General Psychiatry 44, 907–912.CrossRefGoogle ScholarPubMed
White, T, Brown, KW, Woods, JP (1991). Tardive dyskinesia and positive symptoms of schizophrenia. Acta Psychiatrica Scandinavica 83, 377–379.CrossRefGoogle ScholarPubMed
Whitehorn, D, Kopala, LC (2002). Neuromotor dysfunction in early psychosis. Annals of Clinical Psychiatry 14, 113–121.CrossRefGoogle ScholarPubMed
Yarden, PE, DiScipio, WJ (1971). Abnormal movements and prognosis in schizophrenia. American Journal of Psychiatry 128, 327–323.CrossRefGoogle ScholarPubMed