Dimeglio Chloe, Becouarn Guillaume, Topart Philippe, Bodin Rodolphe, Buisson Jean Christophe, Ritz Patrick
Centre Hospitalier Universitaire de Toulouse, Toulouse, France.
Clinique de l'Anjou, Angers, France.
JMIR Med Inform. 2020 Mar 9;8(3):e13672. doi: 10.2196/13672.
Obesity surgery has proven its effectiveness in weight loss. However, after a loss phase of about 12 to 18 months, between 20% and 40% of patients regain weight. Prediction of weight evolution is therefore useful for early detection of weight regain.
This proof-of-concept study aimed to analyze the postoperative weight trajectories and to identify "curve families" for early prediction of weight regain.
This was a monocentric retrospective study with calculation of the weight trajectory of patients having undergone gastric bypass surgery. Data on 795 patients after a 2-year follow-up allowed modeling of weight trajectories according to a hierarchical cluster analysis (HCA) tending to minimize the intragroup distance according to Ward. Clinical judgement was used to finalize the identification of clinically relevant representative trajectories. This modeling was validated on a group of 381 patients for whom the observed weight at 18 months was compared to the predicted weight.
Two successive HCA produced 14 representative trajectories, distributed among 4 clinically relevant families: Of the 14 weight trajectories, 6 decreased systematically over time or decreased and then stagnated; 4 decreased, increased, and then decreased again; 2 decreased and then increased; and 2 stagnated at first and then began to decrease. A comparison of observed weight and that estimated by modeling made it possible to correctly classify 98% of persons with excess weight loss (EWL) >50% and more than 58% of persons with EWL between 25% and 50%. In the category of persons with EWL >50%, weight data over the first 6 months were adequate to correctly predict the observed result.
This modeling allowed correct classification of persons with EWL >50% and could identify early after surgery the patients with potentially less that optimal weight loss. Further studies are needed to validate this model in other populations, with other types of surgery, and with other medical-surgical teams.
肥胖症手术已证明其在减肥方面的有效性。然而，在大约12至18个月的体重减轻阶段之后，20%至40%的患者体重会反弹。因此，预测体重变化对于早期发现体重反弹很有用。
这项概念验证研究旨在分析术后体重轨迹，并识别用于早期预测体重反弹的“曲线族”。
这是一项单中心回顾性研究，计算接受胃旁路手术患者的体重轨迹。对795例患者进行2年随访的数据，根据倾向于最小化组内距离的沃德层次聚类分析（HCA）对体重轨迹进行建模。使用临床判断来最终确定临床相关代表性轨迹的识别。在一组381例患者中对该模型进行验证，将18个月时观察到的体重与预测体重进行比较。
连续两次HCA产生了14条代表性轨迹，分布在4个临床相关类别中：在这14条体重轨迹中，6条随时间系统性下降或下降后停滞；4条下降、上升然后再次下降；2条下降然后上升；2条起初停滞然后开始下降。将观察到的体重与通过建模估计的体重进行比较，可以正确分类98%的体重减轻超过50%的人以及超过58%的体重减轻在25%至50%之间的人。在体重减轻超过50%的人群类别中，前6个月的体重数据足以正确预测观察结果。
该模型能够正确分类体重减轻超过50%的人，并能在术后早期识别出体重减轻可能不理想的患者。需要进一步研究在其他人群、其他类型手术以及其他医疗手术团队中验证该模型。
