Lindsay Wakayama1, Katherine Nameth2, Sarah Adler3, Debra L Safer4. 1. PGSP- Stanford Psy.D. Consortium, Stanford University School of Medicine, Stanford, California. 2. Stanford University School of Medicine, Department of Psychiatry and Behavioral Sciences Stanford, California. 3. Stanford University School of Medicine, Department of Psychiatry and Behavioral Sciences Stanford, California. Electronic address: sadler1@stanford.edu. 4. Stanford University School of Medicine, Department of Psychiatry and Behavioral Sciences Stanford, California. Electronic address: dlsafer@stanford.edu.
Abstract
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.
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.
Authors: Michael P Berry; Elisabeth M Seburg; Meghan L Butryn; Robert W Jeffery; Melissa M Crane; Rona L Levy; Evan M Forman; Nancy E Sherwood Journal: Transl Behav Med Date: 2021-04-26 Impact factor: 3.046
Authors: Claudio E Perez-Leighton; Jeon D Hamm; Ari Shechter; Shoran Tamura; Blandine Laferrère; Jeanine Albu; Danielle Greenberg; Harry R Kissileff Journal: Int J Obes (Lond) Date: 2019-10-22 Impact factor: 5.095