From STOP the Rollercoaster
Copyright © 1996 by Diabetes Services, Inc.
Research on kidney disease has also been promising. Kidney disease is the most devastating complication of diabetes. Measurable kidney damage is found in 43 percent of Type 1 diabetics who have had their disease longer than five years and in 25 percent of those with Type 2 diabetes for 12 years. Diabetes is the most common cause of kidney failure in the United States. One out of every 100 people with diabetes at any time is in kidney failure (dialysis or transplant).
Stages Of Kidney Disease
Kidney damage goes through stages that can be monitored with standard lab tests:
- Microalbuminuria occurs when trace amounts of a protein called albumin begin to leak through the damaged filtering structures of the kidneys. The presence of microalbumin in the urine is often an early warning of kidney disease, but can also be present for other reasons. Normal values on this test are less than 15 to 30 mg/l. The important microalbumin test should be done at least yearly in those who have had diabetes for five years or longer.
The test will help those who have had diabetes a relatively short time but have already started to spill microalbumin. As kidney damage progresses, microalbumin spillage will rise above 200 mg/l and be followed by:
- Proteinuria is the spillage of larger quantities of protein. A standard urinalysis will pick up this spillage (normal is less than 100-150 mg/day, depending on the lab). As damage progresses and protein levels reach about 2000-4000 mg/day, proteinuria is followed by:
- A rising blood creatinine. Creatinine is a normal breakdown product from muscle which the kidneys cleanse from blood (a normal creatinine is 1.1-1.3 mg/dl or less, depending on the lab). As damaged kidneys have more trouble cleansing the blood, creatinine levels rise. After a gradual buildup, toxins in the blood reach a critical stage (usually at a creatinine level between 3 and 8). This critical stage requires:
- Dialysis or a kidney transplant. These technologies replace the severely damaged kidneys in cleansing the blood. Transplant organs are scarce and the operations are costly. Dialysis is disruptive to one's lifestyle and can cost $25,000 to $45,000 each year.
Reversal of Kidney Disease
One of the authors of this book (John Walsh) conducted a study to determine the reversibility of kidney damage in the mid 1980's. He began interventions at an HMO in San Diego in a group of 16 people with proteinuria. At the start of the study, 24-hour urine proteins in the group ranged from 336 to 3,914 mg/day (normal is 50 to 100 mg/day). The study included eight men and eight women. Seven people had Type 1 diabetes and nine had Type 2. The average age was 53 years (range: 24 to 73 years) and average duration of diabetes was 17 years (range: 6 to 29 years).
With kidney disease, protein levels in the urine usually double each year as the disease progresses. A person who is spilling 500 mg of protein per day will reach kidney failure in untreated Type 1 diabetes somewhere between five and 19 years.
Eating a diet low in animal protein and reducing the blood pressure to normal slow kidney damage. The 16 people with diabetes participated in a multiple treatment protocol. Over a period extending to 16 months, 12 of these 16 people showed a 61 percent reduction in protein spillage into the urine. However, one person had a marked rise of 145 percent in proteinuria and three people had a mild rise of 12 percent. These results suggest that 12 out of 16 people reduced their kidney damage and their risk of needing dialysis or transplant.
Treatment included a low protein, almost "vegetarian" diet with about four ounces of animal products of meat, cheese, or milk per day. Most of the people in this study (11 of 16) received an angiotensin converting enzyme inhibitor or ACE inhibitor. ACE inhibitors have been especially promising in protecting the kidneys. Blood sugar control was also improved with insulin adjustments, diet and exercise. The change in each person's 24-hour urine protein is shown in Figure 30.5.
The Norway study noted in Chapter 29 showed similar improvements in kidney function in people who were at the early stage in kidney disease of microalbuminuria. Their improvement came from simply improving their blood sugar control. Another study done in Italy in the late 1970's also showed early kidney disease could be reversed with good blood sugar control.