Vitamin B: Not a DIVINe Therapy for Diabetic Nephropathy
A Long Look on Diabetes
The rapidly increasing incidence of diabetes demands the need for better treatment and management options of its long-term consequences. One major results of diabetes is the development of chronic kidney disease known as diabetic nephropathy. The presence of diabetic nephropathy leads to many effects on the body:
- Leg Swelling
- Loss of Appetite
- Nausea and Vomiting
- Leg and hand numbness/weakness
- Eye damage (retinopathy)
These symptoms are managed by kidney specialists but will have a toll on patients’ quality of life. The role of your physician is to help slow slow the progression of kidney disease. Some research has shown a correlation of increasing blood levels of homocysteine, a protein created in the methionine cycle, with reduced kidney function. The Diabetic Intervention with Vitamins to Improve Nephropathy, aka DIVINe Therapy and study was set out to find out the impact of B vitamins in patients with diabetic kidney disease.
Measuring Kidney Function
Glomerular filtration rate (GFR) is the standard method to measure kidney function and indicates the how quickly blood is cleared of toxins by a single glomerulus (the part of the kidney that blood passes through to be cleaned). Patients with markedly and consistently reduced GFR (at least three months) are considered to have chronic kidney disease.
Homocysteine plays an essential role in several body processes including protein synthesis and cell death. However, like any other chemical, too much of a good thing is dangerous. Hyperhomocysteinemia is the buildup of homocysteine in the blood leading to increased risk of thrombosis (clots). This is especially dangerous in diabetics who already have increased risk of cardiac issues. Some research has shown using B Vitamins reduces homocysteine levels in the blood and which are thought to have some benefit. What about studies looking at B vitamins
The DIVINe Study
Led by Dr. AA House, this 3-year study of 238 patients used high doses of Vitamin B6, B12 and folic acid to reduce homocysteine levels and hypothesized that this effect would in turn slow theprogression of chronic kidney disease as measured by loss of GFR. As vitamin B complex supplements are readily and inexpensively available, the authors postulated that their use as kidney supplements could be a valuable step forward in treatment. Currently, many patients with diabetic nephropathy take B Vitamins as part of a daily regimen but the doses tested in this study were much higher. The study used changes in GFR as their primary measurement while also looking at total homocysteine levels and a battery of secondary outcomes.
The study results suggested that very high dose vitamin B supplementation caused statistically significant loss of kidney function versus placebo treatment. This indicates high-dose Vitamin B supplementation in patients with diabetic nephropathy does not provide the desired results. Taking too much of any supplement is usually harmful, and thus a carefully chosen multivitamin regimen at your physician’s direction is extremely important
Further information about the DIVINe Therapy and study can be found at http://www.ncbi.nlm.nih.gov/
- Vivek Bhalla, Division of Nephrology, Department of Medicine, Stanford University School of Medicine