Should low birth-weight be considered a relevant risk factor for rise in pulse pressure among adult overweight-obese subjects?

Low birth-weight (BW) is related to rise in blood pressure (BP) later in life. Aim of this study is investigating whether presence of overweight-obesity modifies this relationship, independently from any additional correlate of metabolic syndrome. We studied 535 (216 M/319 F) otherwise healthy overweight-obese people (body mass index≥25 kg/m²), recording systolic, diastolic and pulse BP as well as plasma glucose and lipids, additionally interviewing them about BW and weight-change after age of 18 years. The reciprocal of BW was related only to pulse pressure (PP, r=0.14; P=0.04), uniquely in men and individuals with BW≤2500 g had a higher relative risk of having PP above upper quartile (>60 mmHg), independently of sex. After adjusting for confounders each 1 kg rise in BW was associated with 2.84±0.88 (standard error) mmHg decrease in PP; P=0.0042. Moreover, again only among males, the lower BW the higher was the risk of a PP>60 mmHg [odds ratio (95% confidence interval): 2.43 (1.39-4.24); P=0.0018]. In conclusion BW was inversely related only with PP in overweight-obese subjects, uniquely in men, being such effect independent from other correlates of metabolic syndrome. Since elevated PP can be considered a proxy of vascular damage, these findings further stress the importance of inquiring about BW to better stratify the risk of vascular damage, in adult overweight-obese individuals