Pattern of predictive features of continued cannabis use in patients with recent-onset psychosis and clinical high-risk for psychosis
Authors: Penzel Nora , Sanfelici Rachele , Antonucci Linda A. , Betz Linda T. , Dwyer Dominic , Ruef Anne , Cho Kang Ik K. , Cumming Paul , Pogarell Oliver , Howes Oliver , Falkai Peter , Upthegrove Rachel , Borgwardt Stefan , Brambilla Paolo , Lencer Rebekka , Meisenzahl Eva , Schultze-Lutter Frauke , Rosen Marlene , Lichtenstein Theresa , Kambeitz-Ilankovic Lana , Ruhrmann Stephan , Salokangas Raimo K. R. , Pantelis Christos , Wood Stephen J. , Quednow Boris B. , Pergola Giulio , Bertolino Alessandro , Koutsouleris Nikolaos , Kambeitz Joseph ,   the PRONIA Consortium, Koutsouleris Nikolaos , Dwyer Dominic , Ruef Anne , Kambeitz-Ilankovic Lana , Sen Dong Mark , Erkens Anne , Gussmann Eva , Haas Shalaila , Hasan Alkomiet , Hoff Claudius , Khanyaree Ifrah , Melo Aylin , Muckenhuber-Sternbauer Susanna , Kohler Janis , Ozturk Omer Faruk , Popovic David , Rangnick Adrian , von Saldern Sebastian , Sanfelici Rachele , Spangemacher Moritz , Tupac Ana , Urquijo Maria Fernanda , Weiske Johanna , Wosgien Antonia , Kambeitz Joseph , Ruhrmann Stephan , Rosen Marlene , Betz Linda , Lichtenstein Theresa , Blume Karsten , Seves Mauro , Kaiser Nathalie , Penzel Nora , Pilgram Tanja , Lichtenstein Thorsten , Wenzel Julian , Woopen Christiane , Borgwardt Stefan , Andreou Christina , Egloff Laura , Harrisberger Fabienne , Lenz Claudia , Leanza Letizia , Mackintosh Amatya , Smieskova Renata , Studerus Erich , Walter Anna , Widmayer Sonja , Upthegrove Rachel , Wood Stephen J. , Chisholm Katharine , Day Chris , Griffiths Sian Lowri , Lalousis Paris A. , Iqbal Mariam , Pelton Mirabel , Mallikarjun Pavan , Stainton Alexandra , Lin Ashleigh , Salokangas Raimo K. R. , Denissoff Alexander , Ellila Anu , From Tiina , Heinimaa Markus , Ilonen Tuula , Jalo Paivi , Laurikainen Heikki , Lehtinen Maarit , Luutonen Antti , Makela Akseli , Paju Janina , Pesonen Henri , Armio Säilä Reetta-Liina , Sormunen Elina , Toivonen Anna , Turtonen Otto , Solana Ana Beatriz , Abraham Manuela , Hehn Nicolas , Schirmer Timo , Brambilla Paolo , Altamura Carlo , Belleri Marika , Bottinelli Francesca , Ferro Adele , Re Marta , Monzani Emiliano , Percudani Mauro , Sberna Maurizio , D’Agostino Armando , Del Fabro Lorenzo , Perna Giampaolo , Nobile Maria , Alciati Alessandra , Balestrieri Matteo , Bonivento Carolina , Cabras Giuseppe , Fabbro Franco , Garzitto Marco , PiCCuin Sara , Bertolino Alessandro , Blasi Giuseppe , Antonucci Linda A. , Pergola Giulio , Caforio Grazia , Faio Leonardo , Quarto Tiziana , Gelao Barbara , Romano Raffaella , Andriola Ileana , Falsetti Andrea , Barone Marina , Passatiore Roberta , Sangiuliano Marina , Lencer Rebekka , Surman Marian , Bienek Olga , Romer Georg , Dannlowski Udo , Meisenzahl Eva , Schultze-Lutter Frauke , Schmidt-Kraepelin Christian , Neufang Susanne , Korda Alexandra , Rohner Henrik 
Published: March 2022

Continued cannabis use (CCu) is an important predictor for poor long-term outcomes in psychosis and clinically high-risk patients, but no generalizable model has hitherto been tested for its ability to predict CCu in these vulnerable patient groups. In the current study, we investigated how structured clinical and cognitive assessments and structural magnetic resonance imaging (sMRI) contributed to the prediction of CCu in a group of 109 patients with recent-onset psychosis (ROP). We tested the generalizability of our predictors in 73 patients at clinical high-risk for psychosis (CHR). Here, CCu was defined as any cannabis consumption between baseline and 9-month follow-up, as assessed in structured interviews. All patients reported lifetime cannabis use at baseline. Data from clinical assessment alone correctly classified 73% (p < 0.001) of ROP and 59 % of CHR patients. The classifications of CCu based on sMRI and cognition were non-significant (ps > 0.093), and their addition to the interview-based predictor via stacking did not improve prediction significantly, either in the ROP or CHR groups (ps > 0.065). Lower functioning, specific substance use patterns, urbanicity and a lack of other coping strategies contributed reliably to the prediction of CCu and might thus represent important factors for guiding preventative efforts. Our results suggest that it may be possible to identify by clinical measures those psychosis-spectrum patients at high risk for CCu, potentially allowing to improve clinical care through targeted interventions. However, our model needs further testing in larger samples including more diverse clinical populations before being transferred into clinical practice.