Overview

Anorexia nervosa (AN) has among the highest mortality rate of any psychiatric illness, yet we have a poor understanding of the biological causes of this disorder. In this study, we use a novel mechanosensory intervention to examine the basic question of whether individuals with AN have abnormal "gut sensations" and whether such indicators are associated with adverse consequences from the disorder.

Eligibility

Inclusion Criteria:

HC Inclusion criteria:

        i. Body mass index ≥ 18.5. ii. Females, ages 15 to 40 years iii. Women of childbearing age:
        a hormonal (i.e., oral, implantable, or injectable) and single-barrier method, or a
        double-barrier method of birth control must be used throughout the study.
        iv. Independently ambulatory v. Possession of a smartphone with data plan vi. English
        proficiency vii. Willingness and ability to participate in study procedures viii. Provision
        of signed and dated informed consent form
        AN Inclusion criteria:
        i. Primary clinical diagnosis of anorexia nervosa as defined by Laureate Eating Disorders
        Program ii. Body mass index ≥ 18.5. iii. Transitioned from acute clinical status rating to
        residential clinical status or partial/intensive outpatient clinical status rating iv. No
        new medication prescription in the week prior to study randomization, Must be on a stable
        dose of medication for at least 1 week.
        v. Females, ages 15 to 40 years vi. Women of childbearing age: a hormonal (i.e., oral,
        implantable, or injectable) and single-barrier method, or a double-barrier method of birth
        control must be used throughout the study.
        vii. Independently ambulatory viii. Possession of a smartphone with data plan ix. English
        proficiency x. Willingness and ability to participate in study procedures xi. Provision of
        signed and dated informed consent form
        Exclusion Criteria:
        HC Exclusion criteria:
        i. Current diagnosis of a psychiatric disorder per the MINI International Diagnostic
        Interview
        ii. Taking any psychotropic medication
        iii. Active suicidal ideation with intent or plan
        iv. Active cutting or skin lacerating behaviors
        v. Active purging behaviors (specifically, self-induced vomiting), and/or a history of
        severe self-induced vomiting
        vi. Pregnancy as defined by a urine screen during screening, and confirmed during each
        stimulation visit, and must not be lactating
        vii. History of significant gastrointestinal disorder, including any form of inflammatory
        bowel disease or gastrointestinal malignancy (celiac disease is accepted if the subject has
        been treated and is in remission)
        viii. History of complicated/obstructive diverticular disease
        ix. Clinical evidence of significant gastroparesis
        x. Diagnosis of mega-rectum or colon, congenital anorectal malformation, or clinically
        significant rectocele or rectal prolapse
        xi. History of intestinal or colonic obstruction, or suspected intestinal obstruction
        xii. History of intestinal resection (with an exception for appendectomy, cholecystectomy
        and inguinal hernia repair), history of bariatric surgery or evidence of any structural
        abnormality of the gastrointestinal tract that might affect transit
        xiii. History of Zenker's diverticulum, dysphagia, Barrett's esophagus, esophageal
        stricture or achalasia, transesophageal fistula, or eosinophilic esophagitis.
        xiv. Clinical evidence (as judged by the investigator) of respiratory, cardiovascular,
        renal, hepatic, biliary, endocrine, or neurologic disease
        xv. Chronic use of non-steroidal anti-inflammatory drugs (NSAIDs): chronic use is defined
        as taking full dose NSAIDs more than three times a week for at least six months. Subjects
        on cardiac doses of aspirin may be enrolled in the study
        xvi. Cardiac pacemaker, implantable cardioverter defibrillator, implantable infusion
        device, or gastric electrical stimulator
        xxv. Orthostatic hypotension (defined as a drop of ≥ 20 mm Hg in systolic BP or a drop of ≥
        10 mm Hg in diastolic BP when measured shortly after transitioning from lying down to
        standing)
        xxvi. Any other condition which in the opinion of the investigator may adversely affect the
        safety of the subject or would limit the subject's ability to complete the study
        xxvii. No smartphone/computer or limited access to a smartphone/computer
        xxviii. Regular use of any of the following medications or procedures: Medications that may
        substantially affect intestinal motility, prokinetics at high doses (metoclopramide,
        erythromycin, senna, prucalopride), anti-Parkinsonian medications, opiates, opioids,
        calcium-channel blockers, enemas
        xxix. History of a GI bleed within the last 3 months
        xxx. Pelvic floor dysfunction/defecatory disorder, based on subject history
        xxxi. Planning to undergo MRI during study time frame
        xxxii. Any known allergy to soybean or beeswax or Calcium Carbonate
        xxxiii. Bradycardia less than 40 beats per minute
        xxxiv. Pain Disorder
        AN Exclusion criteria:
        i. Active suicidal ideation with intent or plan
        ii. Active cutting or skin lacerating behaviors
        iii. Active purging behviors (specifically, self-induced vomiting), and/or a history of
        severe self-induced vomiting
        iv. Pregnancy as defined by a urine screen during screening, and confirmed during each
        stimulation visit, and must not be lactating
        v. History of significant gastrointestinal disorder, including any form of inflammatory
        bowel disease or gastrointestinal malignancy (celiac disease is accepted if the subject has
        been treated and is in remission)
        vi. History of complicated/obstructive diverticular disease
        vii. Clinical evidence of significant gastroparesis
        viii. Diagnosis of mega-rectum or colon, congenital anorectal malformation, or clinically
        significant rectocele or rectal prolapse
        ix. History of intestinal or colonic obstruction, or suspected intestinal obstruction
        x. History of intestinal resection (with an exception for appendectomy, cholecystectomy and
        inguinal hernia repair), history of bariatric surgery or evidence of any structural
        abnormality of the gastrointestinal tract that might affect transit
        xi. History of Zenker's diverticulum, dysphagia, Barrett's esophagus, esophageal stricture
        or achalasia, transesophageal fistula, or eosinophilic esophagitis.
        xii. Clinical evidence (as judged by the investigator) of respiratory, cardiovascular,
        renal, hepatic, biliary, endocrine, or neurologic disease
        xiii. Chronic use of non-steroidal anti-inflammatory drugs (NSAIDs): chronic use is defined
        as taking full dose NSAIDs more than three times a week for at least six months. Subjects
        on cardiac doses of aspirin may be enrolled in the study
        xiv. Cardiac pacemaker, implantable cardioverter defibrillator, implantable infusion
        device, or gastric electrical stimulator
        xv. Orthostatic hypotension (defined as a drop of ≥ 20 mm Hg in systolic BP or a drop of ≥
        10 mm Hg in diastolic BP when measured shortly after transitioning from lying down to
        standing)
        xvi. Any other condition which in the opinion of the investigator may adversely affect the
        safety of the subject or would limit the subject's ability to complete the study
        xvii. No smartphone/computer or limited access to a smartphone/computer
        xviii. Regular use of any of the following medications or procedures: Medications that may
        substantially affect intestinal motility, prokinetics at high doses (metoclopramide,
        erythromycin, senna, prucalopride), anti-Parkinsonian medications, opiates, opioids,
        calcium-channel blockers, enemas
        xix. History of GI bleed within the last 3 months
        xx. Pelvic floor dysfunction/defecatory disorder, based on subject history
        xxi. Planning to undergo MRI during study time frame
        xxii. Any known allergy to soybean or beeswax, or Calcium Carbonate
        xxiii. Bradycardia less than 40 beats per minute
        xxiv. Pain Disorder