REDEFINING PHENOTYPES IN EDNOS: A LATENT PROFILE ANALYSIS (LPA)

Transcription

1 REDEFINING PHENOTYPES IN EDNOS: A LATENT PROFILE ANALYSIS (LPA) Krug, I; Root, T; Bulik, C; Granero,R; Penelo, E; Jiménez-Murcia, S & Fernández- Aranda, F. Paper read at the Jubilee Congress on Eating Disorders 2010, The 18th International Conference, October 21-23, 2010, Alpbach, Tyrol, Austria

2 INTRODUCTION Latent profile analysis (LPA) are used to identify and model latent classes composed of similar cases in multivariate continuous data. LPA has been used for eating disorder (ED) classification in clinical (e.g.,keel et al., 2004) and community samples (e.g.,duncan et al., 2007). Using this technique, classes have been identified that resemble DSM-IV diagnostic categories; however, subthreshold appearances commonly clustered with full syndrome disorders. To our knowledge only two studies (Eddy et al., 2009; Mitchell et al., 2007), have examined EDNOS using latent variable classification techniques. Previous studies have generally employed eating pathology as indicators in LPA analyses and have used other relevant psychological, physical and behavioural symptoms as validators. To our knowledge, no study has yet tried to capture whether ED subgroups can be adequately characterized by using general psychopathology (GP) and/or personality as indicators.

3 OBJECTIVES To assess empirical classes within EDNOS through LPA. Sample: patients diagnosed across the whole spectrum of EDs. Initial indicators: personality and GP measures. To validate the final solution using demographics, clinical features, motivation, ED symptomatology, personality and impulsive behaviours. To assess the discriminant validity of the empirical classes. Criterion for comparison: the DSM-IV clinical scheme.

4 PARTICIPANTS N=1090: Consecutively admitted ED patients at the ED unit, University Hospital of Bellvitge, Barcelona, Spain 5% 21% 8% 4% 11% 10% 41% AN-Restrictive AN-Binge/Purging BN-Binge/Purging BN-Non-Binge/Purging EDNOS-Restrictive EDNOS-Binge/Purging EDNOS-BED

5 MEASURES 1.) INDICATORS SCL-90-R. General Psychopathology TCI-R..Personality 2.) VALIDATORS EDI-2 EAT-40 ED Symptomatology TCI-R Personality; it was not a useful indicator Clinical Interview: Impulsive behaviours + Clinical variables Questionnaire: Motivation + Sociodemographics

6 RESULTS I Lcstndrd.exe Latent Gold Best-fitting model: 3-profiles using 6 indicators [1.) Obsessive Compulsive; 2.) Interpersonal Sensitivity; 3.) Depression; 4.) Psychoticism; 5.) Anxiety; and 6.) Phobic Anxiety)] of the SCL-90-R. We labeled the three profiles: 1.) mild General Psychopathology (GP); 2.) average GP and 3.) elevated GP. Graph 1: Distribution across the 3 LPA profiles % 33% % Mild GP Average GP Elevated GP 10 0

7 RESULTS II Table 1: Validation analyses for the final LPA solution for demographics, clinical variables Measures Clinical measure Mild GP (N=226) Average GP (N=505) Elevated GP (N=359) Correc. p-value Effect size Significant Contrasts Duration of disorder; yrs 5.61; ; ; <(2=3) Current BMI 21.53; ; ; (1=2)<3 Maximum BMI 25.35; ; ; (1=2)<3 Current Obesity 23; 11.0% 47.0; 9.9% 53.0; 16.1% <3 Family hist. of Obesity 48; 23.2% 125.0; 26.4% 107.0; 32.6% <3

8 RESULTS III Table 2: Validation analyses for the final LPA solution for ED symptomatology Measures ED Symptomatology EAT-40: total score EDI: Drive for Thinness EDI: Body Dissatisfaction EDI: Interoceptive Awar. EDI: Bulimia EDI: Interpers.Distrust EDI: Ineffectiveness EDI: Maturity Fears EDI: Perfectionism EDI: Impulsivity EDI: Asceticism EDI: Social Insecurity EDI: Total Mild GP (N=226) 34.43; ; ; ; ; ; ; ; ; ; ; ; ; Average GP (N=505) 49.64; ; ; ; ; ; ; ; ; ; ; ; ; Elevated GP (N=359) 59.25; ; ; ; ; ; ; ; ; ; ; ; ; 36.2 Correc. p-value Effec t size Significant Contrasts

9 RESULTS IV Table 3: Validation analyses for the final LPA solution for personality and impulsive behaviours Measures Mild GP (N=226) Average GP (N=505) Elevated GP (N=359) Correc. p-value Effec t size Significant Contrasts Personality: TCI-R Harm Avoidance ; ; ; Reward Dependence ; ; ; >(2=3) Self-Directedness ; ; ; >2>3 Cooperativeness ; ; ; >2>3 Transcendence 61.71; ; ; Impulsive Behaviours Self-harming behaviors 31; 15.1% 132.0; 28.1% 157.0; 47.3% 0.09 Suicide attempts 22; 10.8% 79.0; 16.8% 131.0; 39.3% 0.11 Alcohol Abuse 12; 5.9% 51.0; 10.8% 59.0; 17.7% 0.03 Drug Abuse 31; 15.4% 91.0; 19.3% 87.0; 26.1% (1=2)<3

10 RESULTS V Graph 2: Comparison of classes with DSM-IV ED diagnoses EDNOS-BED BN-NP EDNOS- Binge/Purging BN-P AN-BP EDNOS- Restrictive AN-R 0 Mild GP Average GP Elevated GP Discriminant validity: EDNOS-Restrictive and AN-Restrictive subtypes were most commonly included in the mild GP and average GP profiles. BN-Purging patients were most frequently represented in the other two profiles.

11 DISCUSSION The most parsimonious and best fitting LPA model was a three-profile solution defined by mild, average and elevated GP symptoms, based on six subscales from the SCL-90-R scale. It is important to note that that these profiles are severity of pathology gradients not qualitatively different profiles. Clinical symptoms are more useful in classifying ED patients than personality measures. Patients in the elevated GP profile generally exhibited more disturbed eating behavior, maladaptive personality traits and impulsivity. The 3 profiles mapped on some of the ED diagnoses included in the DSM-IV. The finding that AN R and EDNOS-R presented a similar pattern with an overrepresentation in the mild GP and average GP suggests that a distinction between these two ED groups may not be necessary as also shown in earlier studies (Eddy et al., 2008). Interventions in EDs should be designed to address treatment needs along a continuum of problem behavior; not just eating behaviors.

12 ACKNOWLEDGMENT Kings College London: Janet Treasure David Collier Universidad Autonoma de Barcelona Roser Granero Eva Penelo University of North Carolina Cynthia Bulik Tammy Root Hospital Universitario Bellvitge (HUB): Fernando Fernández-Aranda Susana Jiménez-Murcia Isabel Sánchez Nadine Riesco Eva Álvarez-Moya Laura Forcano Zaida Agüera Cynthia Villarejo Juanjo Santamaría Katarina Gunnard Antonio Soto

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