Serum N-acetyl-beta-D-glucosaminidase activity in predicting the development of hypertension

We conducted a prospective study in residents of a small farming community in southwestern Japan to determine whether elevated serum N-acetyl-beta-D-glucosaminidase (NAG) activity would predict future hypertension. The 505 normotensive subjects (blood pressure, < 140/90 mm Hg; mean age, 52 +/- 12 years) were reexamined after 7 years; 111 (22%) had become hypertensive (defined as blood pressure > or = 140/90 mm Hg and/or taking antihypertensive medication at follow-up). After adjustment for age and sex, the development of hypertension was significantly related to body mass index (P < .002), the sum of skinfolds (P < .001), baseline blood pressure (P < .0001), serum cholesterol (P < .01), serum uric acid level (P < .0001), and serum NAG activity (P < .005). Elevated NAG activity showed an independent relationship to future hypertension (P < .005) after adjustments for age, sex, baseline blood pressure (systolic, diastolic, or mean), uric acid level, and the sum of skinfolds. Therefore, elevated serum NAG activity was an effective indicator of future hypertension, and it might therefore be related to functional and/or structural changes in the cardiovascular system.