Neurocognitive Function and Schizophrenia-Proneness in Individuals Dependent on Ketamine, on High Potency Cannabis (‘Skunk’) or on Cocaine

C.J. A. Morgan; S. Duffin; S. Hunt; L. Monaghan; O. Mason; H. V. Curran

doi:10.1055/s-0032-1306310

Pharmacopsychiatry, Table of Contents

Pharmacopsychiatry 2012; 45(07): 269-274
DOI: 10.1055/s-0032-1306310

Original Paper

Neurocognitive Function and Schizophrenia-Proneness in Individuals Dependent on Ketamine, on High Potency Cannabis (‘Skunk’) or on Cocaine

C.J. A. Morgan

¹Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, U.K.

,

S. Duffin

¹Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, U.K.

,

S. Hunt

¹Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, U.K.

,

L. Monaghan

¹Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, U.K.

,

O. Mason

¹Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, U.K.

,

H. V. Curran

¹Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, U.K.

› Author Affiliations

Abstract

Background:

Ketamine, psychostimulants and cannabis have all been associated with psychotic phenomena but no study has directly compared users of these drugs.

Aims:

The aim of this study was to assess schizophrenia proneness and neurocognitive function in individuals dependent upon ketamine, cannabis and cocaine.

Method:

130 volunteers – 29 ‘skunk’ users, 22 cocaine users, 21 ketamine users, along with 28 ‘recreational’ poly-drug users and 30 drug-naïve controls – were assessed on the Schizophrenia Proneness Instrument, Adult version (SPI-A). They were specifically asked to rate symptoms when not under the acute influence of a psychoactive drug.

Results:

Ketamine and skunk users manifested the greatest attentional and cognitive disturbances. The symptom profile of the dependent ketamine users was very similar to that of prodromal individuals who transitioned to psychosis.

Conclusions:

Given the recent rapid rise in use of high potency cannabis and of ketamine, these findings are important and clinicians should be careful to rule out the effects of persistent drug use, especially in users of ketamine or skunk, when assessing an individual’s risk of psychosis. A longitudinal study is needed to differentiate which basic symptoms persist following abstention from ketamine and skunk.

Key words

ketamine - cannabis - cocaine - dependence - prodrome - schizophrenia

Full Text

References

References
1 Cannon TD, Cadenhead K, Cornblatt B et al. Prediction of psychosis in youth at high clinical risk: a multisite longitudinal study in North America. Arch Gen Psychiatry 2008; 65: 28-37
2 Miettunen J, Tormanen S, Murray GK et al. Association of cannabis use with prodromal symptoms of psychosis in adolescence. Br J Psychiatry 2008; 192: 470-471
3 Kristensen K, Cadenhead KS. Cannabis abuse and risk for psychosis in a prodromal sample. Psychiatry Res 2007; 151: 151-154
4 Rosen JL, Miller TJ, D’Andrea JT et al. Comorbid diagnoses in patients meeting criteria for the schizophrenia prodrome. Schizophr Res 2006; 85: 124-131
5 Wylie AS, Scott RT, Burnett SJ. Psychosis due to “skunk”. BMJ 1995; 311: 125
6 D’Souza DC, Perry E, MacDougall L et al. The psychotomimetic effects of intravenous delta-9-tetrahydrocannabinol in healthy individuals: implications for psychosis. Neuropsychopharmacology 2004; 29: 1558-1572
7 Brady KT, Lydiard RB, Malcolm R et al. Cocaine-induced psychosis. J Clin Psychiatry 1991; 52: 509-512
8 Bartlett E, Hallin A, Chapman B et al. Selective sensitization to the psychosis-inducing effects of cocaine: a possible marker for addiction relapse vulnerability?. Neuropsychopharmacology 1997; 16: 77-82
9 Manschreck TC, Laughery JA, Weisstein CC et al. Characteristics of freebase cocaine psychosis. Yale J Biol Med 1988; 61: 115-122
10 Allen RM, Young SJ. Phencyclidine induced psychosis. Am J Psychiatry 1978; 135: 1081-1084
11 Krystal JH, Karper LP, Seibyl JP et al. Subanesthetic effects of the non-competitive NMDA-antagonist, ketamine, in humans. Arch Gen Psychiatry 1994; 51: 199-214
12 Jentsch JD, Roth RH. The neuropsychopharmacology of phencyclidine: from NMDA receptor hypofunction to the dopamine hypothesis of schizophrenia. Neuropsychopharmacology 1999; 30: 201-225
13 Morgan CJ, Curran HV. Acute and chronic effects of ketamine upon human memory: a review. Psychopharmacology (Berl) 2006; 188: 408-424
14 McGorry PD, Killackey E, Yung A. Early intervention in psychosis: concepts, evidence and future directions. World Psychiatry 2008; 7: 148-156
15 Klosterkotter J, Hellmich M, Steinmeyer EM et al. Diagnosing schizophrenia in the initial prodromal phase. Arch Gen Psychiatry 2001; 58: 158-164
16 Simon AE, Cattapan-Ludewig K, Zmilacher S et al. Cognitive functioning in the schizophrenia prodrome. Schizophr Bull 2007; 33: 761-771
17 Pukrop R, Klosterkotter J. Neurocognitive indicators of clinical high-risk states for psychosis: a critical review of the evidence. Neurotox Res 2010; 18: 272-286
18 Solowij N, Hall W, Lee N. Recreational MDMA use in Sydney: a profile of “Ecstasy” users and their experience with the drug. Br J Addict 1992; 87: 1161-1172
19 Gossop M, Griffiths P, Powis B et al. Severity of dependence and route of administration of heroin, cocaine and amphetamines. Br J Addict 1992; 87: 1527-1536
20 Wilson B, Cockburn J, Baddeley A. The Rivermead Behavioural Memory Test. Bury St. Edmunds, UK: Thames Valley Test Company; 1985
21 Baddeley A, Emslie H, Nimmo-Smith I. The spot the word test: a robust estimate of verbal intelligence based on lexical decision. Br J Clin Psychol 1993; 32: 55-65
22 Beck AT. The Beck Depression Inventory (BDI). The Psychological Corporation. Harcourt Brace Jovanovitz Inc; USA: 1978
23 Spielberger C. State-Trait Anxiety Inventory (Form Y); Palo Alto, California. Mind Garden 1983;
24 Schultze-Lutter F, Addington J, Ruhrmann S et al. Schizophrenia Proneness Instrument, Adult version (SPI-A).; Roma, Giovanni Fioriti Editore s.r.l.., 2007
25 Schultze-Lutter F, Steinmeyer EM, Ruhrmann S et al. The dimensional structure of self-reported ‘prodromal’ disturbances in schizophrenia. Clin Neuropsychiatry 2008; 5: 140-150
26 Gross G, Huber G, Klosterkotter J et al. Bonner Skala für die Beurteilung von Basissymptomen (BSABS; Bonn Scale for the Assessment of Basic Symptoms). Berlin Heidelberg: Springer; 1987
27 Gonzalez R. Acute and non-acute effects of cannabis on brain functioning and neuropsychological performance. Neuropsychol Rev 2007; 17: 347-361
28 Pope Jr HG, Gruber AJ, Hudson JI et al. Neuropsychological performance in long-term cannabis users. Arch Gen Psychiatry 2001; 58: 909-915
29 Honey RA, Honey GD, O’loughlin C et al. Acute ketamine administration alters the brain responses to executive demands in a verbal working memory task: an FMRI study. Neuropsychopharmacology 2004; 29: 1203-1214
30 Beveridge TJ, Gill KE, Hanlon CA et al. Review. Parallel studies of cocaine-related neural and cognitive impairment in humans and monkeys. Philos Trans R Soc Lond B Biol Sci 2008; 363: 3257-3266
31 Schultze-Lutter F, Klosterkotter J, Picker H et al. Predicting first episode psychosis by basic symptom criteria. Clin Neuropsychiatry 2007; 4: 11-22
32 Muetzelfeldt L, Kamboj SK, Rees H et al. Journey through the K-hole: Phenomenological aspects of ketamine use. Drug Alcohol Depend 2008; 95: 219-229
33 Cornblatt B, Lencz T, Obuchowski M. The schizophrenia prodrome: treatment and high-risk perspectives. Schizophr Res 2002; 54: 177-186
34 Moore TH, Zammit S, Lingford-Hughes A et al. Cannabis use and risk of psychotic or affective mental health outcomes: a systematic review. Lancet 2007; 370: 319-328
35 Zammit S, Allebeck P, Andreasson S et al. Self reported cannabis use as a risk factor for schizophrenia in Swedish conscripts of 1969: historical cohort study. BMJ 2002; 325: 1199
36 Hardwick S, King LA. Home Office Cannabis Potency Study; St Albans. Home Office Scientific Development Branch 2008;
37 Morgan CJ, Rees H, Curran HV. Attentional bias to incentive stimuli in frequent ketamine users. Psychol Med 2008; 1-10
38 D’Souza DC. Cannabinoids and psychosis. Int Rev Neurobiol 2007; 78: 289-326
39 McCambridge J, Winstock A, Hunt N. 5-Year trends in use of hallucinogens and other adjunct drugs amongst UK dance drug users. Eur Addict Res 2007; 13: 57-64