Dr. Mark Sarnak of Tufts Medical Center started out by saying that the results of the much awaited SPRINT Study will be presented in the following week at the AHA Annual Meeting. In September 2015, the nephrology and hypertension world was acutely (“nephro”-speak) inundated with news about the SPRINT: Systolic blood Pressure Intervention Trial (highlighting SBP < 120 to be much more beneficial as compared to current guidelines that recommend target SBP < 140 or < 150 in elderly). Apparently, this study which was supposed to conclude in 2017 was stopped early because of significant evidence that would be “potentially lifesaving.”
So what are the other issues? Well, he talked about the link between low salt diet and ESRD/ CVD mortality, and the JNC 8 and KDIGO recommendations:
- 2013 AHA/ACC Guideline
- Decrease sodium intake (strong evidence)
- Intake of ≤ 2.4 g of sodium/day (moderate evidence)
- Decrease intake to 2.0 g of sodium/day, unless contraindicated (level 1C)
Based on current evidence, higher levels of sodium intake should be avoided but lower targets need to be better defined.
Then he discussed the current KDIGO recommendations for BP Targets for CKD patients with and without diabetes:
|Albuminuria||BP Target||Preferred Agent|
|< 30 mg/d||< 140/90 mm Hg (1B)||None|
|30-300 mg/d||< 130/80 mm Hg (2D)||ACE or ARB (2D)|
|> 300 mg/d||< 130/80 mm Hg (2C)*||ACE or ARB (1B)|
* For CKD patents with diabetes, the evidence rating for this target is “(2D)”
This lecture kept me a bit hanging though, as I thought he would give us some idea about how the SPRINT trial is actually going to revolutionize the current thinking about intensive vs standard BP control or how it would contradict JNC 8. SPRINT enrolled 9361 participants without diabetes; of whom, 2648 had CKD (with proteinuria < 1 g/day). They were randomized into 2 groups: (1) Intensive BP Control: SBP < 120 mm Hg, and (2) Standard BP Control: SBP < 140 mm Hg. Outcomes included; CVD, progression of kidney disease, and neurological outcomes.
In particular, I am very much interested in the renal outcomes:
“- Main renal outcome: Composition of initiation of ESRD therapy or a confirmed 50% decline in eGFR (CKD subgroup only)
– Other renal outcome: initiation of ESRD therapy or a 30% decline in eGFR to < 60 mL/min/m2 (non-CKD subgroup only)
– Incident proteinuria: doubling of urinary albumin-to-creatinine ratio from < 10 mg/g to > 10 mg/g (entire cohort)”
According to recent press release, “the intervention in this trial, which carefully adjusts the amount or type of BP medication to achieve a target systolic pressure of 120 millimeters of mercury (mm Hg), reduced rates of cardiovascular events…by almost a third and the risk of death by almost a quarter, as compared to the target systolic pressure of 140 mm Hg.”
At present, there remains significant uncertainty as far as the target SBP in CKD patients are concerned.
Post by Dr. Edgar Lerma, AJKD Blog Advisory Board member.
Check out all of AJKD Blog’s coverage of Kidney Week 2015!