LAUSR

Improving cardiovascular risk profile in surgery candidates may reduce surgical risk and ameliorate prognosis. In particular, in the case of bariatric patients, weight reduction before surgery might play a mechanistic role [1] reducing postoperative complications, decreasing operating time, facilitating technical aspects of surgery and improving comorbidities such as glycemic control and cardiovascular performance. Additional potential mechanisms range from a betterment of immunological and hormonal profiles to an improvement of hemodynamics and reversal of autonomic nervous system (ANS) impairment by exercise training possibly combined with healthy nutrition programs [2]. Length of intervention is an important variable: long lasting weight management programs (usually 3–6 months) are associated to a combination of improved vagal function and reduced sympathetic activation, but determine higher operational and economic cost. Few data are available regarding the effects on ANS control of short lasting (few weeks) interventions that would be easier to add to preoperative routines In a feasibility study, we hypothesized that in bariatric surgery candidates a four-week prehabilitation based on low calories balanced diet and non-supervised physical activity could improve metabolic profile, hemodynamic load and cardiac autonomic regulation [3]. Five weeks before planned bariatric surgery, 39 candidates (BMI ≥ 40 kg/m2, age 45 ± 9 yrs, normo-tolerant glucose status) were enrolled (T0) at the Obesity Surgery Unit, Pisa University Hospital. Patients with diabetes, pregnancy, or established clinical conditions known to alter autonomic regulation were excluded. Within the week, all subjects were evaluated (baseline, T1) and started the lifestyle intervention program [4] based on low calories balanced diet and non-supervised physical activity. After four weeks, subjects were again examined (intervention, T2). The study followed the Declaration of Helsinki, effective December 13, 2001 and was approved by the Ethics Committee (protocol N. 140/2014); all Subjects signed a consent. The lifestyle program comprised individual assessment at T1: