Nutrition, Health Behavior and Obesity Research Lab

Long-term outcomes following Metabolic-Bariatric Surgery (MBS)

This research program includes a series of prospective and retrospective cohort studies examining clinical, skeletal, metabolic, nutritional, and behavioral outcomes following metabolic-bariatric surgery (MBS). Although MBS is highly effective for weight reduction and metabolic improvement, extended follow-up beyond the early postoperative years remains limited. This program is composed of parallel ongoing projects aimed to characterize long-term weight trajectories, nutritional and metabolic outcomes including skeletal changes, and to identify factors associated with sustained success or suboptimal post-surgical response, such as patients characteristics and behavioral patterns. This research is conducted within the Bariatric Surgery Unit at Hadassah–Ein Kerem Medical Center. Below are key ongoing projects.

Related sub-projects 

Weight loss outcomes and lifestyle patterns following sleeve gastrectomy - This retrospective cohort study, based on a pre-existing prospective database, examines long-term outcomes beyond 10 years following sleeve gastrectomy. Data from clinical records of patients who underwent primary sleeve gastrectomy are combined with structured follow-up questionnaires administered at multiple timepoints post-surgery, to evaluate weight trajectories, recurrent weight gain, medical status, medication use, postoperative side effects, lifestyle habits, engagement in multidisciplinary follow-up, and patient-reported satisfaction. Anthropometric indices, including BMI, percentage of excess weight loss, total body weight loss, and recurrent weight gain, are analyzed to characterize patterns of long-term weight response and behavioral correlates. 

Long-Term Changes in Bone Mineral Density After Laparoscopic Sleeve Gastrectomy - This prospective cohort study extends follow-up from a previously conducted randomized clinical trial in women undergoing sleeve gastrectomy. After completion of the parent trial and our report on two-year outcomes, the original cohort is currently followed for additional evaluation of the long-term bone health status after the surgery. Assessments include bone mineral density at the hip, femoral neck and lumbar spine, by dual-energy X-ray absorptiometry (DXA), alongside bone turnover markers and clinical parameters collected across multiple follow-up visits. 

Bone Health outcomes following One-Anastomosis Gastric Bypass Surgery - This prospective study examines the mid- and longer-term effects of one-anastomosis gastric bypass, a widely performed bariatric procedure, on skeletal health. The study evaluates changes in bone mineral density and bone turnover markers following surgery. In addition, the research investigates the relationship between postoperative bone changes and nutritional intake, with particular focus on dairy consumption, as well as other factors that may predict bone loss. These include eating habits, lifestyle patterns, anthropometric and body composition parameters measured by both BIA and DXA, and relevant clinical and biochemical indicators. By integrating surgical, dietary, and lifestyle domains, the study aims to improve understanding of determinants of bone health following One-anastomosis gastric Bypass

Pregnancy Outcomes, Lifestyle Behaviors, and Follow-Up Patterns Following Metabolic–Bariatric Surgery - This project examines maternal, behavioral, and neonatal outcomes among women who conceive following MBS, with a focus on sleeve gastrectomy and one-anastomosis gastric bypass. Using clinical data combined with structured follow-up surveys, the study evaluates gestational weight gain, neonatal birth weight, surgery-to-conception interval, and pregnancy-related complications, alongside lifestyle behaviors, supplementation practices, physical activity, and engagement in multidisciplinary follow-up during pregnancy. The project also explores reproductive counseling, contraceptive practices, unintended pregnancies, and patient-perceived gaps in care. By integrating obstetric, nutritional, and behavioral domains, this research aims to inform structured, multidisciplinary models of care for women who conceive after MBS.

Setting

Bariatric Surgery Unit, Hadassah–Ein Kerem Medical Center

Research Team & students involved

Tamar Avshalom, Hamzy Sirhan, Hosam Mahajna, Donia Kaloti, Moria Uziel, Haya Subhi, Anael Sayada.

Primary Supervision

Dr. Tair Ben-Porat

Prof. Ram Elazary

Dr. Mahmud Abu Ghazala

Status

Ongoing retrospective and prospective data collection and analyses