Plasma insulin-like growth factor-1 level and risk of incident hypertension in nondiabetic women.

BACKGROUND: Insulin-like growth factor-1 may be involved in regulation of blood pressure through multiple pathways; however, the prospective association between plasma insulin-like growth factor-1 level and risk of hypertension has never been explored.
METHODS: We prospectively examined the association between plasma insulin-like growth factor-1 level and the risk of incident hypertension among 2046 women without a history of hypertension or diabetes. Cox proportional hazards regression models were used to adjust for potential confounders.
RESULTS: We identified 181 incident cases of hypertension during 4 years of follow-up. After adjusting for plasma insulin-like growth factor binding protein-3 level and other potential confounders, women in the top tertile of insulin-like growth factor-1 had decreased risk of incident hypertension (relative risk 0.56, 95% confidence interval 0.35-0.91) compared with women in the bottom tertile. After further adjusting for C-peptide level and C-reactive protein level in subsets of participants who also had those markers measured, the association between insulin-like growth factor-1 and risk of incident hypertension remained robust.
CONCLUSIONS: Higher circulating insulin-like growth factor-1 level is associated with a decreased risk of incident hypertension among nondiabetic women.