High sodium intake is associated with masked hypertension in Japanese patients with type 2 diabetes and treated hypertension

Abstract

BackgroundKnowledge regarding the association between dietary sodium intake and the incidence of masked hypertension is limited.MethodsA total of 193 Japanese type 2 diabetic outpatients who had been treated with antihypertensive agents and with office blood pressures <140/90 mm Hg were recruited. Masked hypertension was defined as having office blood pressure <140/90 mm Hg and 24-h mean ambulatory blood pressure ≥130/80 mm Hg. The dietary sodium intake was estimated by measuring the 24-h urinary sodium excretion.ResultsMasked hypertension was found in 128 (66.3%) patients. An age-and sex-adjusted univariate logistic regression analysis showed that urinary albumin excretion, reninangiotensin system inhibitor use, office systolic blood pressure, and amount of dietary sodium intake were significantly associated with masked hypertension. A multivariate logistic regression analysis also identified an older age, reninangiotensin system inhibitor use, an office elevated systolic blood pressure, and high dietary sodium intake to be independently associated with masked hypertension. When compared with those who consumed a low salt diet (sodium <120 mEq/day), the odds ratio for the risk of exhibiting masked hypertension in patients who consumed a medium salt diet (sodium 120 to <200 mEq/day) or a high salt diet (sodium 200 mEq/day) were 5.3 (P<0.001) and 12.6 (P<0.001), respectively.ConclusionsMasked hypertension is a common feature in type 2 diabetic patients being treated for hypertension. The observed association with sodium intake raised the hypothesis that excessive sodium intake may play a part in the genesis of masked hypertension in these patients. © 2012 American Journal of Hypertension, Ltd.