Accelerometer-measured versus self-reported physical activity levels in women before and up to 48 months after Roux-en-Y Gastric Bypass

• Published in: BMC surgery 2020-02, Vol.20 (1), p.39-39, Article 39
• Main Authors: Possmark, Sofie, Sellberg, Fanny, Willmer, Mikaela, Tynelius, Per, Persson, Margareta, Berglind, Daniel
• Format: Article
• Language: English
• Subjects: Accelerometer; Accelerometers; Bariatric surgery; Exercise; Gastric bypass; Gastrointestinal surgery; Hospital patients; Hospitals; inget Strategiskt forskningsområde (SFO); Leisure; Measurement; Medical care quality; Medicin och hälsovetenskap; no Strategic Research Area (SFO); Physical activity; Physical fitness; Questionnaires; Self report; Surgery; Surgical outcomes; Time; Women
• ISSN: 1471-2482; 1471-2482
• DOI: 10.1186/s12893-020-00699-7

Roux-en-Y Gastric Bypass (RYGB) patients overestimate their time spent in moderate-to-vigorous physical activity (MVPA) to a greater extent post-surgery than pre-surgery. However, there is no data on discrepancy between self-reported and accelerometer-measured MVPA beyond nine months post-RYGB. The aim was to investigate how the duration of MVPA (main outcome) differs when comparing a self-administered questionnaire to accelerometer-data from pre-surgery and up to 48 months post-RYGB. Twenty-six (38%) RYGB-treated women with complete data from the original cohort (N = 69) were included. Participants were recruited from five Swedish hospitals. Mean pre-surgery BMI was 38.9 (standard deviation (SD) = 3.4) kg/m and mean age 39.9 (SD = 6.5) years. MVPA was subjectively measured by a self-administered questionnaire and objectively measured by the ActiGraph GT3X+ accelerometer at 3 months pre-RYGB and 9- and 48 months post-RYGB. Means and SD were calculated at 3 months pre- and 9- and 48 months post-RYGB. We calculated the P-values of the differences with Wilcoxon Signed-Rank test. For correlations between the self-administered questionnaire and the accelerometers, Spearman's rank correlation was used. Participants significantly overestimated (i.e. self-reported more time spent in MVPA compared to accelerometry) their MVPA in a higher degree post- compared to pre-RYGB surgery. Compared to pre-surgery, self-reported MVPA increased with 46.9 and 36.5% from pre- to 9- and 48 months, respectively, whereas changes were a 6.1% increase and 3.5% decrease with accelerometers. Correlations between self-reported and accelerometer-measured MVPA-assessments were poor at all measurement points (r = 0.21-0.42) and only significant at 48 months post-RYGB (P = 0.032). The discrepancy between self-reported and objectively assessed MVPA within the same individual is greater up to 48 months post-RYGB compared to before surgery. To help bariatric patients understand and hopefully increase their physical activity behaviors post-surgery, objective measures of physical activity should be used.