Asymptomatic bacteriuria--a long-term study.

Four percent of the women in a population study 1969-1970 had asymptomatic bacteriuria (ABU). 15 years later a reinvestigation was carried out, in women-born 1913-1948. 40 women with ABU and 40 age-matched healthy controls from the population study participated. The frequency of symptomatic urinary tract infections (UTI) had been significantly higher in the ABU group than in the control group during follow-up, but nobody had developed progressive renal disease. Three women in the ABU group and one in the control group had low urine concentrating capacity. All other osmolality values were within normal limits, although there was a significant difference between the two groups. The age-dependent decrease after 15 years was the same in both groups. The number of new hypertensives was the same in both groups. A total of 37.5% were hypertensive in the ABU group and only 12.5% in the control group, but as hypertension had been excluded in the control group at the first investigation the groups could not be compared in this respect.