Serum N-acetyl-beta-D-glucosaminidase activity in a large population--a useful index of cardiovascular impairment.

Serum N-acetyl-beta-D-glucosaminidase (NAG) levels were measured in 1080 residents in Tanushimaru, Fukuoka, aged 20 to 84 years old, during a periodical epidemiological survey performed in 1982. Thirteen pregnant women were excluded from this study. Serum NAG levels showed an increase with age, but were not different between sexes. We found high serum NAG values in those with high blood pressure, high serum total cholesterol, low serum HDL-cholesterol, or reduced creatinine clearance rate, and women with high serum uric acid, increased skinfold thickness, or high hematocrit. Multiple regression equation was as follows: NAG = 3.53 + 0.07 (age) + 0.14 (hematocrit) + 0.03 (total skinfold thickness) + 0.04 (systolic blood pressure) - 0.03 (HDL-cholesterol) - 0.04 (mean blood pressure) - 0.01 (creatinine clearance). The multiple correlation coefficient was 0.37 (F = 24.4). We suggest that NAG may be a useful index in screening cardiovascular impairment and for cardiovascular risk factors.