Body weight loss by very-low-calorie diet program improves small artery reactive hyperemia in severely obese patients.

Background: Endothelial dysfunction is a major underlying mechanism for the elevated cardiovascular risk associated with increased body weight. We aimed to assess the impact of weight loss induced by an intensive very-low-calorie diet (VLCD) on arterial wall function in severely obese patients (SOP).

Methods: Thirty-four SOP were admitted to the metabolic ward of the hospital for a 3-week period. A VLCD characterized by a liquid diet providing 800 kcal/day was administered. The small artery reactivity to postischemic hyperemia index (saRHI), a surrogate marker of endothelial function, was assessed before and 1 week after hospital discharge. Anthropometry and biochemical parameters were also measured. Obese and non-obese age- and gender-matched groups were recruited for baseline comparisons.

Results: SOP had significantly lower saRHI compared with obese and non-obese individuals. SaRHI significantly increased after the intervention in SOP (1.595 ± 0.236 vs. 1.737 ± 0.417, p = 0.015). A significant improvement in glucose (p = 0.026), systolic blood pressure (p = 0.049), LDLc (p < 0.001), and inflammatory parameters was observed. Body weight loss was associated with a higher saRHI (r = -0.385, p = 0.033), and it was the main determinant of saRHI variation independently of confounders (β -0.049, IC 95 % -0.091-0.008, p = 0.021).

Conclusions: Weight loss induced by a VLCD in SOP improved small artery reactivity, and it was associated with the amelioration of metabolic and inflammation markers. Endothelial dysfunction may be softened by body weight loss interventions and useful in the management of cardiovascular risk factors in SOP.