Effects of GH replacement on endothelial function and large-artery stiffness in GH-deficient adults: a randomized, double-blind, placebo-controlled study

Summary objectives Hypopituitary adults with growth hormone deficiency (GHD) have an increased cardiovascular mortality, although the mechanisms remain unclear. Endothelial dysfunction, characterized by reduced nitric oxide (NO) bioavailability, is a key early event in atherogenesis and is associated with increased vascular smooth muscle tone and arterial stiffening. design and patients In a randomized, double‐blind, placebo‐controlled study, we investigated the effects of GH replacement on endothelial function and large‐artery stiffness in 32 GHD adults (19 males, 13 females) (age range 19–64 years) over a 6‐month period. Thirty‐two age‐ and sex‐matched healthy controls were also studied. measurements Endothelial function was assessed using ultrasonic wall tracking to measure flow‐mediated dilatation (FMD) of the brachial artery. Large artery stiffness was assessed by pulse wave analysis of the radial artery pressure waveform, allowing determination of the corresponding central arterial pressure waveform and derivation of the augmentation index. Fasting lipid profiles, glucose and insulin were also measured. results At baseline, FMD (mean ± SD) was impaired in GH‐deficient subjects vs. controls (3·4 ± 2·3 vs. 5·7 ± 2·0%, P