ORIGINAL INVESTIGATION Is attention to detail a similarly strong candidate endophenotype for anorexia nervosa and bulimia nervosa? MARION E. ROBERTS, KATE TCHANTURIA & JANET L. TREASURE Institute of Psychiatry, Division of Psychological Medicine, Section of Eating Disorders King’ s College London, London, UK Abstract Objectives. To investigate whether attention to detail is a similarly strong candidate endophenotype of anorexia (AN) and bulimia nervosa (BN), and to explore the incidence and clinical correlates of attention to detail. Methods. A total of 266 women (including AN, BN, recovered AN, unaffected sisters of AN/BN & control women) undertook a thorough clinical assessment and were administered two neuropsychological measures of attention to detail (Group Embedded Figure Test; Rey-Osterrieth Complex Figure). Results. Superior attention to detail was found across all AN groups including recovered AN and unaffected AN sisters. Those with BN and their unaffected sisters showed a profile more consistent with poor global integration. The combined effect of superior attention to detail and poor global integration (“weak coherence”) was present in 42.3% of active cases and corresponded with a more severe illness, elevated obsessive-compulsive symptoms, and a higher likelihood of comorbid clinical anxiety and self-harm. Conclusions. Attention to detail is a stronger candidate endophenotype of AN compared to BN, where poor global integration may be more relevant. The unique contribution of both aspects of weak coherence (superior attention to detail/poor global integration) requires further exploration and understanding in both eating disorders. Integrating cognitive remediation of these traits into treatment for the subset of patients it is relevant for may improve outcome. Key words: Anorexia, bulimia, neuropsychology , cognition, endophenotypes, siblings Introduction Anorexia nervosa (AN) is a life-threatening illness with the highest mortality of any functional psychi- atric disorder (Harris and Barraclough 1998). Despite this, AN remains inadequately understood and the efficacy of standardised treatment is poor (Bulik et al. 2007; Treasure et al. 2010). Better evi- dence is available for the treatment of bulimia ner- vosa (BN); however, long-term recovery following treatment remains poor or unknown (Shapiro et al. 2007). As in other fields of psychiatry, research is turning its focus toward the study of underlying bio- logical mechanisms that may increase risk and/or maintain pathological behaviour (Benjamin et al. 2001). Identifying and then targeting heritable endo- phenotypes in treatment may provide a more positive outcome for eating disorder patients (Bulik et al. 2007; Steiger and Bruce 2007; Treasure et al. 2007). One medium used to identify such candidate endo- phenotypes is the study of altered neurocognition (Gottesman and Gould 2003; Flint and Munafo 2007). Weak coherence refers to the tendency for an individual to focus their attention on detail to the extent that the more global significance (or contex- tual meaning) of such detail is lost (Frith 1989; Happe and Booth 2008). Though somewhat recently applied to the eating disorder population, consistent empirical evidence for attention to detail has been found in a number of neuropsychological studies of women with AN and BN using tasks such as the embedded figure test (Tokley and Kemps 2007; Lopez et al. 2008b), matching familiar figures task (Southgate et al. 2008b), Rey-Osterrieth complex figure (Lopez et al. 2008b,d; Tenconi et al. 2010) and the fragmented pictures task (Harrison et al. 2011). A systematic review of this literature reports medium to large effect sizes across tasks (Lopez et al. 2008c), suggesting a pronounced bias toward detailed pro- cessing in those with eating disorders compared to the community. Preliminary evidence has also been Correspondence: Dr Marion Roberts, 5th Floor Bermondsay Wing, Guy’ s Hospital, London SE5 9RT, UK. Tel: +44 207 188 0181; Fax: +44 207 188 0167. E-mail: marion.roberts@kcl.ac.uk (Received 17 June 2011; accepted 12 October 2011) The World Journal of Biological Psychiatry, 2011; Early Online: 1–12 ISSN 1562-2975 print/ISSN 1814-1412 online © 2011 Informa Healthcare DOI: 10.3109/15622975.2011.639804 World J Biol Psychiatry Downloaded from informahealthcare.com by Kings College London on 03/23/12 For personal use only.