By Serena Gordon
TUESDAY, Dec. 29 (HealthDay News) -- The incidence of end-stage kidney disease, one of the most serious complications of diabetes, rose steadily in people with diabetes for decades. But, in 1996, the rate of diabetes-related end-stage kidney disease finally began to decline.
Since that time, the incidence has dropped steadily -- about 3.9 percent a year, a new government study finds.
"The incidence had decreased for all age groups and for both men and women," noted study author Nilka Rios Burrows, an epidemiologist with the U.S. Centers for Disease Control and Prevention.
Although the study was not designed to find the cause behind the decline, Burrows said that based on other studies, they believe that early detection and treatment of kidney disease in people with diabetes is likely one factor behind the decline. In addition, better control of diabetes and high blood pressure -- especially the use of medications that lower blood pressure and may protect the kidneys as well -- also likely played a role in the decline, she said.
Results of the study will be published in the January issue of Diabetes Care.
Diabetes is a leading cause of end-stage renal disease (ESRD), driving about 44 percent of new cases in 2006, according to background information in the study.
"Diabetes isn't just hard on the kidneys. It's really a multi-organ, multi-system disease. But, the kidneys tend to show damage earlier because they function like a sentinel organ," explained Dr. Sheldon C. Chaffer II, an assistant professor in the division of nephrology at Scott and White Hospital in Temple, Tex. "High blood sugar causes inflammation and damage to the lining of the small and large blood vessels. The kidneys are a tangle of blood vessels and they utilize about 20 percent of the body's blood supply at all times, which makes them very susceptible to damage from high blood sugar."
For the current study, Burrows and her colleagues gathered data from the U.S. Renal Data System on anyone with diabetes who began end-stage renal disease treatment between 1990 and 2006.
The actual number of people with diabetes undergoing ESRD treatment has increased dramatically -- from 17,727 in 1990 to 48,215 in 2006. However, during that same time, the incidence of diabetes has also increased dramatically.
When the researchers controlled the data to account for the increase in people with diabetes, they found an initial period from 1990 to 1996 when the ESRD incidence increased from 299 people per 100,000 people with diabetes to 343 per 100,000.
But, from 1996 through 2006, the rate then dropped an average of 3.9 percent a year -- from 343 people per 100,000 people with diabetes to 197.7 per 100,000. In people under 45, the decline was even more dramatic, dropping 4.3 percent per year.
Burrows said there are skeptics who believe that because there are many people with newly diagnosed diabetes, and because ESRD usually develops 15 to 20 years after the onset of diabetes, this decline is only temporary. But Chaffer said he's hopeful the decline is real and stems from more aggressive intervention in early kidney disease.
"We recognize kidney disease earlier [now] and we're better able to manage diabetes and high blood pressure," he added.
Burrows said that the incidence of ESRD dropped across all racial groups, although the decline in the Hispanic population didn't reach statistical significance. "We may need some additional strategies for prevention in the Hispanic community," suggested Burrows. But, she added that because they didn't have as many years of data on Hispanics as they did for other races, it's also possible that the researchers just didn't have enough information to see a statistically significant decline.
For anyone with diabetes, Burrows said the most important message from her study is that there are things you can do to prevent serious kidney disease. "If you have diabetes and high blood pressure, talk to your doctor about kidney disease and what you can do to prevent it if you don't [already] have it, or how to delay its progression if you do have kidney disease," she said.