THURSDAY, April 21 (HealthDay News) -- Chronic kidney disease is common among Americans over 80 years of age and is often linked with heart disease, a new study says.

Researchers examined the prevalence of chronic kidney disease in 1,028 octogenarians in four U.S. communities enrolled in the long-term Cardiovascular Health Study All Stars. The prevalence of chronic kidney disease varied from 33 to 51 percent, depending on whether the researchers used blood serum levels of creatinine or cystatin C as markers of the disease.

The findings highlight the fact that using different formulas to assess kidney function in people in their 80s results in different estimates of the chronic kidney disease prevalence in this age group, the investigators said.

The study authors noted that no "gold standard" to estimate the prevalence of chronic kidney disease in octogenarians has been developed or validated.

However, no matter which formula was used to assess kidney function, chronic kidney disease in octogenarians was associated with cardiovascular disease. Participants with chronic kidney disease were 1.5 to two times more likely than those without chronic kidney disease to have coronary heart disease, heart failure or stroke, according to the report.

The study is published in the April 21 online issue of the Clinical Journal of the American Society of Nephrology.

More information

The American Academy of Family Physicians has more about chronic kidney disease.