EATING DISORDERS - Includes Anorexia Nervosa, Bulimia (PDF)

1 MH 12 AFHSB Surveillance Case Definitions FINAL May 2018 Case Definition and Incidence Rules For surveillance purposes, a case of an eating disorder is defined as:  One hospitalization with a case defining diagnosis of an eating disorder (see ICD9 and ICD10 code lists below) in the primary or secondary diagnostic position.  One outpatient medical encounter with a case defining diagnosis of an eating disorder (see ICD9 and ICD10 code lists below) in the primary diagnostic position [see Case Definition and Incidence Rule Rationale below]. Incidence rules: For individuals who meet the case definition:  The incidence date is considered the date of the first hospitalization or outpatient medical encounter that includes a defining diagnosis of an eating disorder. (continued on next page) EATING DISORDERS Includes Anorexia Nervosa, Bulimia Nervosa, Binge Eating Disorder and Eating Disorders Not Otherwise Specified Background This case definition was developed by the Armed Forces Health Surveillance Branch (AFHSB) for the purpose of epidemiological surveillance of a condition important to military-associated populations. Clinical Description Eating disorders are characterized by significant disturbances in eating behavior and weight regulation. The conditions include anorexia nervosa (AN), bulimia nervosa (BN), binge eating disorder (BED), and eating disorders not otherwise specified. Anorexia nervosa is characterized by a refusal to maintain normal body weight, fear of gaining weight or becoming fat, and a disturbed perception of one’s body weight. Bulimia nervosa is characterized by recurrent episodes of binge eating, inappropriate compensatory behavior to prevent weight gain such as self-induced vomiting, laxative and diuretic use, fasting and excessive exercise. Binge eating disorder is characterized by recurrent episodes of eating large quantities food, often to the point of discomfort, and associated with feelings of loss of control, distress and guilt. All of the disorders are more common among adolescents and young adult women in industrialized societies. They often coexist with other disorders such as depression, anxiety, and substance abuse. To restore normal eating behavior and nutrition, treatment is often necessary; treatment includes psychotherapy, medical care, nutrition counseling, and medication.1,2 1 Armed Forces Health Surveillance Center. Diagnosis of Eating Disorders Among Active Component Service Members, U.S. Armed Forces, 2004-2013. Medical Surveillance Monthly Report (MSMR). 2014 Sept; 21(9): 8-12. 2 Eating Disorders: About More Than Food. National Institutes of Mental Health. See https://www.nimh.nih.gov/health/publications/eating-disorders/index.shtml; accessed July 2017.  2 MH 12 AFHSB Surveillance Case Definitions FINAL May 2018 Case Definition and Incidence Rules (continued)  Individuals with more than one eating disorder recorded are considered an incidence case only once, the first recorded diagnosis of either anorexia nervosa or bulimia nervosa is given priority, and both are prioritized over binge eating disorder and eating disorders not otherwise specified.  An individual is considered an incident case only once per surveillance period Exclusions:  Individuals with a case defining diagnosis prior to the surveillance period. Codes The following ICD9 and ICD10 codes are included in the case definition: Condition ICD-10-CM Codes ICD-9-CM Codes F50 (eating disorders) Anorexia nervosa F50.0 (anorexia nervosa…) 307.1 (anorexia nervosa) - F50.00 (unspecified) - F50.01 (restricting type) - F50.02 (binge eating/purging type) Bulimia nervosa F50.2 (bulimia nervosa) 307.51 (bulimia nervosa) Other eating disorders F50.8 (other eating disorders) 307.59 (other disorders of eating) - F50.81 (binge eating disorder) - F50.89 (other specified eating disorder) F50.9 (eating disorder, unspecified) 307.50 (eating disorder, unspecified) Development and Revisions  In July of 2017 the case definition was updated to include ICD10 codes.  This case definition was developed in September of 2014 by the Medical Surveillance Monthly Report (MSMR) staff for an article on eating disoders.1 The case definition was developed based on reviews of the ICD9 and ICD10 codes, the scientific literature, and previous AFHSB analyses.  3 MH 12 AFHSB Surveillance Case Definitions FINAL May 2018 Case Definition and Incidence Rule Rationale  This case definition requires only one outpatient medical encounter in the primary diagnostic position to define a case. Given eating disorders are often chronic or comorbid conditions, investigators may want to explore a case definition that requires two outpatient visits in the primary diagnostic position or one outpatient visit in any diagnostic position to increase sensitivity. Code Set Determination and Rationale  Binge eating disorder was added as an official diagnosis to the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition and also incorporated into the ICD10 coding system.  For a more specific case definition investigators may want to consider using code V65.3 (dietary surveillance and counseling). Reports AFHSB reports on eating disorders in the following reports:  Periodic MSMR articles Review July 2017 Case definition reviewed and adopted by the AFHSB Surveillance Methods and Standards (SMS) working group. Sept 2014 Case definition developed by AFHSC MSMR staff. Comments None