I have a relative who is overweight, about 105 kilograms (about 231 pounds). Some days, he is fine, others he has sugar in his urine and occasional impotence. How long until he has kidney damage? How long until he develops nonreversible impotence? Many other relatives have occasionally uncontrolled diabetes, but no one has problems with their kidneys or impotence.

Interestingly, you provide a very important piece of the history. Kidney disease in patients with diabetes tends to follow along family lines. The fact your family does not have this is encouraging. Complications that involve the kidney and the nerves (that lead to impotence) are related to the duration of the diabetes and level of control during that time. The best indicator of control and complications risk is the hemoglobin A1c as this has been directly related to the risk of complications. The lower the A1c, the lower the risk of complications. I would suggest your relative have his physician do a test called microalbumin. If this test remains normal, it is very unlikely your relative will develop kidney disease. If it becomes positive, it is a signal he should talk to his physician about drugs that have kidney protective effects. There is encouraging information that suggests these medicines really do protect one from progressive kidney disease. Impotence is a more difficult problem to deal with. Sometimes it is caused by other medications used for high blood pressure, stress, or from blood vessel disease. Some of the medications now commercially available have been very helpful for patients with diabetes and impotence. I would suggest your relative speak to his physician about the use of these medications if problems persist.

JTL