Microalbuminuria: Associations with height and sex in non-diabetic subjects

Abstract

Objectives - To study the association(s) between microalbuminuria and cardiovascular risk factors in non-diabetic subjects. Design - Patients aged 40-75 years were randomly selected from a general practice list and invited to participate. Setting - Health centre in inner city London. Subjects - Of those invited, 1046 out of 1671 (62.6%) attended. Subjects were excluded for the following reasons: not being white (44); urinary albumin excretion rate >200 μg/min (3); having a urinary infection (5); taking penicillamine or angiotensin converting enzyme inhibitors (7); older than 75 (2); having diabetes (25); missing data on glucose concentration (1). Main outcome measures - Glucose tolerance test results, albumin excretion rate from overnight and timed morning collections of urine; blood pressure; height. Results - Mean albumin excretion rate was significantly lower in women than men (mean ratio 0.8, 95% confidence interval (0.69 to 0.91)). Mean albumin excretion rate was significantly associated with age, blood pressure, and blood glucose concentration (fasting, 1 hour, and 2 hour) in men and inversely with height. Men who had microalbuminuria in both samples were significantly shorter (by 5 cm (1.3 to 9.3 cm)) than those who had no microalbuminuria in either sample when age was taken into account. In the case of women only systolic pressure was significantly associated with albumin excretion rate. Conclusions - Microalbuminuria and short stature in men are associated. Cardiovascular risk has been associated with both of these factors and with lower birth weight. The inverse association of microalbuminuria with height is compatible with the suggestion that factors operating in utero or early childhood are implicated in cardiovascular disease. The higher prevalence of microalbuminuria in men compared with women may indicate that sex differences in cardiovascular risk are reflected in differences in albumin excretion rate.