Comparative Analysis of Salt Taste Perception among Diabetics, Hypertensives and Diabetic Hypertensives

Impaired salt taste perception has been described in patients with essential hypertension. Hypertension occurs more frequently in diabetics than the general population. We compared salt taste perception among patients with type 2 diabetes (n=59), hypertension (n=57) and concurrent hypertension and diabetes (n=56) using graded NaCl solution (0 - 400 mmol/L). Sixty age, sex and body mass index-matched healthy individuals served as controls. Main outcome measures included taste threshold for NaCl recognition, and salt taste insensitivity defined as taste threshold for NaCl recognition > 100 mmol/L. Diabetic hypertensives had insignificantly higher duration of diabetes than the diabetic normotensives (5.0 ± 4.1 versus 3.5 ± 2.6, P= 0.07). The prevalence of NaCl taste insensitivity did not differ significantly among hypertensives, diabetic hypertensives and diabetics normotensives (52.6% versus 46.4% versus 40.7%; P=0.3). Compared to the controls, normotensive diabetics were at higher risk of salt taste insensitivity (40.7% versus 18.3%, P=0.01; OR=3.1, 95% CI =1.2-7.7). In the diabetic normotensive group, NaCl taste recognition threshold correlated positively with systolic blood pressure (r=0.501, P=0.001), diastolic blood pressure (r=0.411, P=0.04) and duration of diagnosis of diabetes (r=0.402, P=0.02). These results suggest that salt taste acuity is impaired in type 2 diabetics and could be a contributory factor to the high prevalence of hypertension in the diabetic population. Keywords: Salt taste perception, type 2 diabetes, hypertensionNigerian Medical Practitioner Vol. 53 (1&2) 2008: pp. 7-1