Hi, I am sorry I am late to reply. First thing I would ask is how well your diabetes is controlled. High blood sugars definitely contribute to kidney damage.
Consider, a truly normal hba1c is 5 or lower and reflects and average blood sugar of less than 100. If your hba1c is 7.0 (a common target) then average blood sugar is around 170. It is known that damage definitely occurs as blood sugars are higher than 140. So what is the answer to all of this?
Certainly to maintain your brain, you have to maintain your body. For T2D the key pathology is that there is insulin resistance. This is caused by excess intake of carbohydrates and exaccerbated by being overweight and / or inactive. Not saying at all that you are any of these, because I don't know you. :)
I would suggest, even while lithium is being looked at, you also take measures to optimise blood sugar control.
The best way I know are the following:-
1. Low carb diet (or even keto), cutting all added sugars, grains, starchy and processed foods and focusing on whole real foods.
2. Lose weight if overweight. Yes, easy to say and harder to do, but item 1 will help.
3. Take up regular exercise, daily, if you do not already do this. Try to do something that you enjoy, which will make it easier to be consistent with.
4. Get enough sleep and manage stress.
5. Enjoy the company of friends and family.
Please ask any questions you may have. Wishing you well.
I would suggest googling the specific lab tests that were abnormal and read about test limitations. For example I had a test recently that was alarming. Then I read that particular test is prone to inaccurate results based on your condition at the time of testing. My 2+ hrs travel 6 hours of extreme duress, exposure, lack of facilities, etc prior to testing was a known contraindication. If only my Dr had known...
Lithium nephropathy is a spectrum of functional and structural renal damage caused by lithium ingestion. Lithium toxicity spectrum includes: (1) acute intoxication, (2) nephrogenic diabetes insipidus/polyuria-polydipsia syndrome, and (3) chronic renal disease, the former which may be reversible and the latter which may be irreversible. Characteristic radiology findings are numerous microcysts within normal-sized kidneys. MRI is the most sensitive modality.
As you have already pointed out, your kidney disease is probably related to your diabetes. However, if it is determined that lithium is the culprit, your psychiatrist may consider substituting lithium with other treatment alternatives.
Hello and welcome to the forum. Thanks for this interesting, thought provoking question. I think most health care professionals would tell you that it is all intermingled. If one area is having issues, it will likely affect the other area. As to how much, everyone is different. This article is a good read to accompany your question. https://www.cdc.gov/healthyplaces/healthtopics/mental.htm and an even better read https://psychcentral.com/lib/the-relationship-between-mental-and-physical-health#1
They generally go hand in hand. How is your mental health? Since you are on medication, hopefully that is well controlled.
When are you next seeing your doctor to discuss the findings of your testing? Lithium does indeed have an effect on kidneys. Talk to your doctor about that. https://www.health.harvard.edu/newsletter_article/lithium-induced-kidney-problems But as you know, issues related to your diabetes can also include kidney issues. How well controlled is your diabetes?