The inaccuracy of self-reported weight loss in post-operative bariatric surgery patients

ABSTRACT

Background: The COVID-19 pandemic has accelerated the adoption of telemedicine in post-surgical follow-up visits. Studies suggest that this practice is appropriate for bariatric surgery patients. One of its limitations, however, is providers' reduced ability to monitor post-op weight loss. This study aims to determine whether bariatric surgery patients' weight loss is accurately reported during virtual follow-up visits, relative to traditional office visits. Methods: We examined the medical records of 227 patients who underwent bariatric surgery in 2019 and 2020. The weights of these patients at their 6-month post-op visits were collected, and it was noted whether the weight was measured in the office or self-reported. The results were stored in a REDCap database. Analysis was performed with R using a Wilcoxon test. Results: Of a potential 227 patients, six-month weights were obtained for 146 patients (94 in-person and 52 self-reported). The in-person group averaged 10.28 (+/-3.59) BMI weight loss while the telemedicine group averaged 12.71 (+/-4.23) BMI weight loss (p < 0.01). The average weight loss at 6 months were 27.8 (+/-13.0) kg and 37.8 (+/-12.8) kg for in-person and telemedicine patients respectively (p < 0.01). Conclusions: We found a significant difference in weight loss between the in-person and telemedicine groups, suggesting that weight changes among the latter group may not be accurately reported. This calls into question the utility of weight loss data obtained from bariatric surgery patients during the pandemic, as the vast majority is self-reported. Limitations of this study include a small sample size, fluctuations in patient weight loss patterns due to the pandemic, and our inability to obtain confirmatory in-office weights from the telemedicine group. However, the significant deviation from the in-person group suggests inaccurate reporting, whether intentional or unintentional. Further studies are needed to establish the accuracy of self-reported weight changes in bariatric surgery patients.