I am passionate about solving the access crisis in the behavioral health system. I focus on redesign of care delivery systems using data, clinical innovation and technology to increase access to care.
Clinical Associate Professor, Psychiatry and Behavioral Sciences
Honors & Awards
Annual Chairman's Award 2019 Excellence in Leadership & Professionalism, Stanford University Department of Psychiatry & Behavioral Science (6/2019)
Internship: VA Palo Alto Health Care Psychology Training (2010) CA
Fellowship: Stanford University Psychology Postdoctoral Fellowship (2013) CA
Professional Education: PGSP-Stanford PsyD Consortium (2010) CA
Current Research and Scholarly Interests
I am interested in the design and delivery of clinical care using, data and technology. I have focused on disordered eating behaviors and obesity.
Bringing Virtual Reality From Clinical Trials to Clinical Practice for the Treatment of Eating Disorders: An Example Using Virtual Reality Cue Exposure Therapy.
Journal of medical Internet research
2020; 22 (4): e16386
Novel treatment options for eating disorders (EDs) are critically needed to enhance treatment outcomes and reduce the rates of treatment dropouts. On average, only 50% of individuals receiving evidence-based care remit, whereas 24% drop out before treatment completion. One particularly promising direction involves integrating virtual reality (VR) with existing evidence-based treatments (EBTs) such as cue exposure therapy (CET). Across psychiatric disorders, VR-based interventions are demonstrating at least preliminary efficacy and noninferiority to traditional treatments. Furthermore, VR technology has become increasingly portable, resulting in improved acceptance, increased access, and reductions in cost. However, more efficient research processes may be needed to uncover the potential benefits of these rapid technological advances. This viewpoint paper reviews existing empirical support for integrating VR with EBTs (with a focus on its use with EDs) and proposes key next steps to more rapidly bring this innovative technology-based intervention into real-world clinic settings, as warranted. VR-CET for EDs is used to illustrate a suggested process for developing such treatment enhancements. We recommend following a deployment-focused model of intervention development and testing to enable rapid implementation of robust, practice-ready treatments. In addition, our review highlights the need for a comprehensive clinical protocol that supports clinicians and researchers in the implementation and testing of VR-CET and identifies key missing protocol components with rationale for their inclusion. Ultimately, this work may lead to a more complete understanding of the full potential of the applications and integrations of VR into mental health care globally.
View details for DOI 10.2196/16386
View details for PubMedID 32324145
Brain-Responsive Neurostimulation for Loss of Control Eating: Early Feasibility Study.
Loss of control (LOC) is a pervasive feature of binge eating, which contributes significantly to the growing epidemic of obesity; approximately 80 million US adults are obese. Brain-responsive neurostimulation guided by the delta band was previously found to block binge-eating behavior in mice. Following novel preclinical work and a human case study demonstrating an association between the delta band and reward anticipation, the US Food and Drug Administration approved an Investigational Device Exemption for a first-in-human study.To assess feasibility, safety, and nonfutility of brain-responsive neurostimulation for LOC eating in treatment-refractory obesity.This is a single-site, early feasibility study with a randomized, single-blinded, staggered-onset design. Six subjects will undergo bilateral brain-responsive neurostimulation of the nucleus accumbens for LOC eating using the RNS® System (NeuroPace Inc). Eligible participants must have treatment-refractory obesity with body mass index ≥ 45 kg/m2. Electrophysiological signals of LOC will be characterized using real-time recording capabilities coupled with synchronized video monitoring. Effects on other eating disorder pathology, mood, neuropsychological profile, metabolic syndrome, and nutrition will also be assessed.Safety/feasibility of brain-responsive neurostimulation of the nucleus accumbens will be examined. The primary success criterion is a decrease of ≥1 LOC eating episode/week based on a 28-d average in ≥50% of subjects after 6 mo of responsive neurostimulation.This study is the first to use brain-responsive neurostimulation for obesity; this approach represents a paradigm shift for intractable mental health disorders.
View details for DOI 10.1093/neuros/nyaa300
View details for PubMedID 32717033
A randomized, placebo-controlled crossover trial of phentermine-topiramate ER in patients with binge-eating disorder and bulimia nervosa.
The International journal of eating disorders
OBJECTIVE: Open trials suggest phentermine/topiramate ER (PHEN/TPM-ER), Food and Drug Administration (FDA) approved for obesity, has utility for binge eating. With no randomized controlled trials (RCTs) yet performed, this trial aimed to evaluate PHEN/TPM-ERs efficacy and safety in a crossover RCT for patients with binge-eating disorder (BED) or bulimia nervosa (BN).METHOD: Participants were randomized to 12-weeks PHEN/TPM-ER (3.75mg/23mg-15mg/92mg) or placebo followed by 2-weeks drug washout, then 12-week crossover. Demographics, vitals, eating disorder behaviors, mood, and side effects were measured. Primary outcome was objective binge-eating (OBE) days/4-weeks; secondary outcomes included binge abstinence. Mixed-effect models estimated treatment effects, with fixed effects adjusting for treatment, study period, and diagnosis.RESULTS: The 22 adults (BED = 18, BN = 4) were female (96%), Caucasian (55%), aged 42.9 (SD = 10.1) years with body mass index = 31.1 (SD = 6.2) kg/m2 . Baseline OBE days/4-weeks decreased from 16.2 (SD = 7.8) to 4.2 (SD = 8.4) after PHEN/TPM-ER versus 13.2 (SD = 9.1) after placebo (p<.0001), with abstinence rates = 63.6% on PHEN/TPM-ER versus 9.1% on placebo (p<.0001). Weight changes = -5.8 kg on PHEN/ TPM-ER versus +0.4 kg on placebo. Drop-out = 2 (9%) on PHEN/TPM-ER and 2 (9%) on placebo, with few side effects. Vital sign changes with PHEN/TPM-ER were minimal and similar to placebo. Responses were not significantly different for BED versus BN.DISCUSSION: This first RCT to evaluate the efficacy and safety of PHEN/TPM-ER for BED/BN found this drug combination significantly more effective at reducing binge eating than placebo and well tolerated. However, with only four participants with BN, findings regarding the safety of PHEN/TPM-ER in patients with BN must be taken with caution.TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT02553824 registered on 9/17/2015. https://clinicaltrials.gov/ct2/show/NCT02553824.
View details for DOI 10.1002/eat.23192
View details for PubMedID 31721257
PILOT OF A REMOTELY-DELIVERED INTERVENTION TO IMPROVE DIETARY ADHERENCE AND WEIGHT-LOSS OUTCOMES IN POST-BARIATRIC PATIENTS
OXFORD UNIV PRESS INC. 2019: S95
View details for Web of Science ID 000473349400195
- Replication and extension of dietary adherence as a predictor of suboptimal weight-loss outcomes in postbariatric patients SURGERY FOR OBESITY AND RELATED DISEASES 2019; 15 (1): 91–96
Replication and extension of dietary adherence as a predictor of suboptimal weight-loss outcomes in postbariatric patients.
Surgery for obesity and related diseases : official journal of the American Society for Bariatric Surgery
BACKGROUND: Sarwer et al. found that poor dietary adherence at 6 months postoperatively predicted lower weight loss.OBJECTIVES: To replicate and extend these findings.SETTING: University bariatric clinic.METHODS: Fifty-four adults (72% female; age 51.1 ± 11.3 yr; mean body mass index [BMI] = 43.8 ± 7.4 kg/m2; 53.7% = Roux-en-Y gastric bypass, 42.6% = laparoscopic sleeve gastrectomy, and 3.7% = gastric banding) were identified as low or high dietary adherers following the method of Sarwer et al. Patients self-reported dietary adherence with a 9-point Likert scale. Splitting the group at the median, low adherers scored <7 and high dietary adherers ≥7. BMI, percentage excess weight loss (%EWL), and percentage total weight loss (%TWL) were prospectively assessed at 12, 24, and 36 months. Two-tailed independent t tests and Cohen's d effect sizes were used to compare between-group outcomes.RESULTS: BMI did not differ between low (n = 24) and high (n = 30) dietary adherers at 6 months after surgery. At 12 months, the BMI of low (n = 17) adheres was significantly higher (34.1 ± 4.61 versus 30.3 ± 3.90 kg/m2, P = .006, d = 0.90) than that of high (n = 25) adherers, with significantly less %EWL (49.0 ± 24% versus 70.7 ± 21.5%; P = .004; d = 0.95) and %TWL (20.7 ± 11.5% versus 28.9 ± 10.5, P = .02, d = 0.74). At 24 months, BMI remained significantly higher for low (n = 12) versus high (n = 10) adherers (33.7 ± 4.77 versus 29.7 ± 3.82 kg/m2, P = .045, d = 0.92), but %EWL and %TWL were not significantly different, despite large effect sizes. At 36 months, moderate effects supported continued higher BMIs and lower %EWL and %TWL for low (n = 5) versus high (n = 8) adherers. Attrition from follow-up was 22.2% (12 mo), 59.3% (24 mo), and 75.9% (36 mo). Post hoc analyses revealed no impact of baseline characteristics on low follow-up rates except younger age (at 1 yr).CONCLUSIONS: Findings that 6-month postoperative dietary adherence predicts 12-month BMI, %EWL, and %TWL were replicated. Medium to large effects suggest findings extend to 24 and 36 months, with low follow-up rates likely affecting statistical significance.
View details for PubMedID 30541684
Correlates of Dietary Adherence and Maladaptive Eating Patterns Following Roux-en-Y Bariatric Surgery
2018; 28 (4): 1130–35
Self-reported poor dietary adherence following bariatric surgery is associated with less successful weight loss outcomes. Poor dietary adherence is a global construct lacking specificity regarding its underlying, clinically targetable, maladaptive eating behaviors.Comprehensive online survey data were obtained from a sample of 274 adults who underwent Roux-en-Y surgery in the prior 1-12 years. Correlations between dietary adherence and six eating-related behaviors were calculated, with the frequency of each behavior reported on a 7-point scale. Linear regression modeling was applied.All six maladaptive eating behaviors were highly correlated with dietary adherence (Pearson's r > 0.5): grazing (r = - 0.565), mindless eating (r = - 0.572), loss of control eating (r = - 0.517), eating "more than is best" after dinner (r = - 0.518), eating foods off of one's plan (r = - 0.557), and "when I eat something off-plan, I feel like I have blown it and I give up and eat more" (r = - 0.574). The estimated regression coefficients in the linear model was statistically significant, [F(5, 261) = 60.006, p < 0.001] and accounted for approximately 54% of the variance of global dietary adherence (R 2 = 0.535, adjusted R 2 = 0.526).Six maladaptive eating behaviors accounted for a highly significant portion of post-Roux-en-Y patients' poor self- reported dietary adherence. Prospective studies are needed to investigate the relationship between targetable maladaptive eating behaviors and bariatric surgery outcomes.
View details for PubMedID 29076007
Study protocol and rationale for a randomized double-blinded crossover trial of phentermine-topiramate ER versus placebo to treat binge eating disorder and bulimia nervosa.
Contemporary clinical trials
2018; 64: 173–78
Bulimia nervosa (BN) and binge eating disorder (BED) are associated with severe psychological and medical consequences. Current therapies are limited, leaving up to 50% of patients symptomatic despite treatment, underscoring the need for additional treatment options. Qsymia, an FDA-approved medication for obesity, combines phentermine and topiramate ER. Topiramate has demonstrated efficacy for both BED and BN, but limited tolerability. Phentermine is FDA-approved for weight loss. A rationale for combined phentermine/topiramate for BED and BN is improved tolerability and efficacy. While a prior case series exploring Qsymia for BED showed promise, randomized studies are needed to evaluate Qsymia's safety and efficacy when re-purposed in eating disorders. We present a study protocol for a Phase I/IIa single-center, prospective, double-blinded, randomized, crossover trial examining safety and preliminary efficacy of Qsymia for BED and BN.Adults with BED (n=15) or BN (n=15) are randomized 1:1 to receive 12weeks Qsymia (phentermine/topiramate ER, 3.75mg/23mg-15mg/92mg) or placebo, followed by 2-weeks washout and 12-weeks crossover, where those on Qsymia receive placebo and vice versa. Subsequently participants receive 8weeks follow-up off study medications. The primary outcome is the number of binge days/week measured by EDE. Secondary outcomes include average number of binge episodes, percentage abstinence from binge eating, and changes in weight/vitals, eating psychopathology, and mood.To our knowledge this is the first randomized, double-blind protocol investigating the safety and efficacy of phentermine/topiramate in BED and BN. We highlight the background and rationale for this study, including the advantages of a crossover design.Clinicaltrials.gov identifier NCT02553824 registered on 9/17/2015. https://clinicaltrials.gov/ct2/show/NCT02553824.
View details for PubMedID 29038069
Early Adherence Targeted Therapy (EATT) for Postbariatric Maladaptive Eating Behaviors
COGNITIVE AND BEHAVIORAL PRACTICE
2016; 23 (4): 548-560
View details for Web of Science ID 000384872800018
- What variables are associated with successful weight loss outcomes for bariatric surgery after 1 year? SURGERY FOR OBESITY AND RELATED DISEASES 2014; 10 (4): 697-704
How smartphone applications may be implemented in the treatment of eating disorders: case reports and case series data
Advances in Eating Disorders: Theory, Research and Practice
View details for DOI 10.1080/21662630.2014.938089
Group dialectical behavior therapy adapted for obese emotional eaters; a pilot study
2012; 27 (4): 1141-1147
Dialectical Behavior Therapy (DBT) has been shown to effectively target binge eating disorder (BED). This study pilots the effectiveness of group DBT for obese "emotional eaters" to reduce eating psychopathology and achieve weight maintenance. Thirty-five obese male and female emotional eaters receiving 20 group psychotherapy sessions of DBT adapted for emotional eating were assessed at end-of-treatment and 6 month follow-up for reductions in eating psychopathology and weight maintenance. DBT resulted in significant reductions in emotional eating and other markers of eating psychopathology at the end-of-treatment that were maintained at follow-up. The drop-out rate was very low, with only 1 participant dropping from treatment. Thirty-three (94%) of the sample provided data at every assessment point. Of these, 80% achieved either weight reduction or weight maintenance after treatment and throughout the follow-up period. The effect size for weight reduction was small. This pilot study demonstrates group DBT targeting emotional eating in the obese to be a highly acceptable and effective intervention for reducing eating related psychopathology at both at end-of-treatment and during follow-up. The ability of DBT to limit the upward trajectory of weight gain in obese patients with high degrees of emotional eating suggests that DBT may also help limit the increase or even prevent onset of obesity related morbidity in these patients.
View details for DOI 10.3305/nh.2012.27.4.5843
View details for Web of Science ID 000307042300025
View details for PubMedID 23165554
A Prospective Assessment of Psychosocial Factors Among Bariatric Versus Non-bariatric Surgery Candidates
2011; 21 (10): 1570-1579
Psychological factors are considered potential contraindicators to bariatric surgery, but inconsistently predict surgical outcomes. We examined biomedical and psychosocial predictors of future bariatric candidacy in a population of veterans enrolling in a multidisciplinary weight management program.Ninety-five obese veterans meeting bariatric surgery eligibility criteria participating in a weight control intake class from 2007 to 2008 completed the MOVE!23 questionnaire to assess biomedical, psychiatric, social, and eating behavior factors. Twenty-five patients from this cohort completed or obtained approval for bariatric surgery during the next 2 years of follow-up.Patients progressing to bariatric candidacy over follow-up differed from non-bariatric patients in multiple areas, including reporting significantly lower rates of depression (28% versus 48.7%, respectively; p = 0.04) and smoking (4% versus 16%; p = 0.05), better self-rated health (e.g., 28% versus 10.7% rating themselves as in excellent or very good health), and averaged 50% fewer cardiovascular risk factors (p = 0.01). Bariatric patients also rated themselves as significantly faster eaters (p = .03) and as having higher rates of obsessive compulsive disorder (OCD; 28% versus 7%; p = 0.04). Depression and OCD status predicted patients going on to bariatric candidacy independent of body mass index (BMI), biomedical status, and demographic factors.Our results suggest that many of the commonly cited psychosocial contraindicators to bariatric surgery are already lower in patients considered for surgery relative to BMI equivalent treatment-seeking peers not approved for surgery. These differences may help explain inconsistent relationships between psychosocial factors and bariatric surgery outcomes.
View details for DOI 10.1007/s11695-010-0287-8
View details for Web of Science ID 000295175700014
View details for PubMedID 20872090
View details for PubMedCentralID PMC3179584