Normal or improved cardiovascular risk factors in IGF-I-deficient adults with growth hormone receptor deficiency.
Level 4 - case-series / case-control
Cross-sectional case-control comparison of a rare genetic cohort against relative controls
PubMed 38677286 · doi:10.1016/j.medj.2024.03.022
What was done
Cardiovascular function, vascular damage markers, and metabolic risk factors were assessed in individuals with growth hormone receptor deficiency (GHRD/Laron syndrome) and unaffected relative controls sharing similar geographical and socioeconomic backgrounds. Measurements were conducted across two phases: an initial group of 30 individuals (16 GHRD, 14 controls) evaluated at USC, expanding to a total of 44 individuals (21 GHRD, 23 controls) examined in Ecuador and the US. Measures included serum glucose, insulin, blood pressure, cardiac dimensions, pulse wave velocity, carotid artery intima-media thickness, creatinine, lipid levels, and carotid atherosclerotic plaques.
What was found
Compared to controls, GHRD subjects displayed lower serum glucose, insulin, blood pressure, creatinine, smaller cardiac dimensions, lower carotid artery intima-media thickness, and similar pulse wave velocity. GHRD subjects had a lower proportion of carotid atherosclerotic plaques than controls (7% versus 36%, p = 0.1333) despite having elevated low-density lipoprotein cholesterol levels. Absolute numerical values for metabolic and cardiovascular parameters were not reported in the abstract.
Why it matters
These findings suggest that severe lifelong IGF-I deficiency from growth hormone receptor dysfunction does not elevate cardiovascular disease risk and may protect against atherosclerotic plaque formation despite elevated LDL cholesterol.
Limits
The sample size is very small (n = 44 total), leaving clinical endpoints underpowered. The cross-sectional design prevents assessing long-term cardiovascular outcomes or causality, and numerical values for most continuous biomarkers were not reported in the abstract.
Cited by
- supports Circulating IGF-1 levels in individuals with Laron syndrome are approximately 10% of normal circulating IGF-1 levels.