- Age: 18-70
- Abnormal Cr 1.2-7 women 1.4-7 in men.
- MAP of 125 or less (160/100)
- Proteinuria less than 10g per day
- No diabetics
The primary end-point was a composite of death or dialysis and just about every patient in both groups (95.7%) reached this end-point preventing a separation between the groups (p=0.5). Likewise there was no separation with regards to time to dialysis (p=0.4).
My take is this fits well with what I tell my patients when they ask me about protein restriction. I have always counseled patients against protein restriction. The two largest RCT were both negative trials (The Modification of Diet in Renal Disease and the Northern Italian Cooperative Study Group). Additionally my patients do not have the benefit of dedicated and repeated nutritional couseling that the patients in these trials receive. My fear is that with little therapeutic upside there is signifigent risk of malnutrition from overzealous protein restriction.
This study probably does not apply to my worry as I doubt patients would adhere to a very low-protein diet.
My other concearn regarding low-protein diets is patients need to get calories from somewhere. Calories can only come from protein, carbohydrates or fat. Considering that the vast majority of CKD patients are destined to die before dialysis I worry that my advice for protein restriction will result in increased carbohydrates (bad for diabetes and possibly CV disease, see Richard Johnson’s fructose hypertension research) and/or increased fats (bad for CV disease) and enhance the risk of death from the more likely outcome.