NaCl sensitivity of essential hypertensive patients is related to insulin resistance

Abstract

This study showed that essential hypertensive patients with high NaCl sensitivities were relatively insulin resistant compared with those with low NaCl sensitivities, independently of confounding factors such as age, obesity and glucose intolerance. Insulin resistance was not associated with overt hyperinsulinaemia among these patients.

Increased insulin resistance in salt sensitive essential hypertension

“…Journal of Human Hypertension (2001) 15, 481-485 jects. 5,[9][10][11][12][13][14][15] Some authors have found higher degrees of insulin resistance in salt sensitive hypertensive patients, 9,10 whereas others have found no relationship in hypertensives, 11 obese 12 or normotensives. 13 Finally, two reports in hypertensive patients have found an increase in insulin sensitivity in salt sensitive hypertensive subjects.…”

“…Although only one author 9 used the less time-consuming intravenous method to determine blood pressure sensitivity to salt intake, diagnostic criteria were completely different among all studies that used oral salt load. There is also a high heterogeneity in the methodology applied to measure insulin sensitivity, and only three studies used the euglycaemic hyperinsulinaemic clamp technique, 8,9,13 considered the gold standard method. 16 Another limitation is the inclusion of some effect modifiers in the studied groups.…”

“…14,15 On the other hand, obesity and glucose tolerance impairment were exclusion criteria in only two studies. 9,10 Given the existence of the commented heterogeneity in previous studies, we have used accurate methodologies to analyse the potential relationship between insulin resistance and sensitivity to the pressor effect of salt intake in a group of non-obese essential hypertensives without glucose intolerance.…”

Metabolic syndrome and blood pressure: the salty connection

“…Paradoxically, it has been shown that the anti-natriuretic effect of insulin is preserved in obese and diabetic subjects with and without hypertension despite insulin resistance, suggesting that hyperinsulinemia exacerbates sodium reabsorption and increase blood pressure in these conditions. 3 Of note, several reports have supported a role of insulin resistance in salt-sensitive hypertension, 4,5 which is not necessarily associated with overt hyperinsulinemia. 4 Indeed, the insulin resistance index positively correlates with the sodium sensitivity index and is negatively correlated with fractional excretion of sodium measured during high dietary salt.…”

“…3 Of note, several reports have supported a role of insulin resistance in salt-sensitive hypertension, 4,5 which is not necessarily associated with overt hyperinsulinemia. 4 Indeed, the insulin resistance index positively correlates with the sodium sensitivity index and is negatively correlated with fractional excretion of sodium measured during high dietary salt. 6 Giner et al 7 have reproduced most of these results under strictly controlled experimental conditions.…”