Washington, Mar 3 (UNI) African-American adolescents may have greater risk of kidney damage even before high blood pressure has developed, due to the presence of a certain protein in their urine, a US study says.
A study published in Hypertension, a journal of the American Heart Association found that black teens had a 10 per cent higher rate of albumin in their urine than their white counterparts, despite the fact that both groups had normal blood pressure. Albumin is a protein known as an early indicator of kidney dysfunction in adults.
''Microalbuminuria, excessive amounts of albumin in the urine, is a common problem among diabetics too,'' study leader Dr Gregory Harshfield of Medical College of Georgia said.
The study was aimed at finding the prevalence of the problem in a healthy population of children and adolescents and the impact of race, sex, sodium-handling and blood pressure on microalbuminuria, Dr Harshfield said.
The researchers studied 317 healthy teens aged 15 to 18, who were placed on a three-day sodium-controlled diet prior to testing on day four. Testing consisted of a two-hour baseline period, a one-hour stress period and a two-hour post-stress period.
At the end of each hour, urine samples were collected to determine the levels of microalbumin.
The higher levels correspond to a tendency to retain sodium after stress, Dr Harshfield said adding that sodium retention is normal during stress but should normalise after the stressor has passed.
Children and adolescents, particularly black children, can display reduced kidney function prior to the onset of hypertension, the study indicated.
It would be prudent to measure levels of microalbuminuria in high-risk patients, Dr Harshfield noted.
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