
Current guidelines recommend systolic blood pressure below 120 mm Hg in patients with chronic kidney disease. However, according to Chen Tang, PhD, and colleagues, the renoprotective effect of intensive blood-pressure lowering in patients with immunoglobulin A nephropathy (IgAN) is unclear. The researchers conducted a study at Peking University First Hospital in China, to examine the effect of intensive blood pressure control on the progression of IgAN.
The study cohort included 1530 patients with IgAN. The researchers sought to define the relationship between baseline and time-updated blood pressure and composite kidney outcomes (development of end-stage renal disease or a 30% decline in eGFR). Multivariable causal hazard models and marginal structural models were used to model baseline and time-updated blood pressures.
During a median follow-up of 43.5 months, 24.0% of study participants experienced the composite kidney outcomes. There were no significant associations observed between baseline blood pressure and the composite outcomes.
Using marginal structural models with time-updated systolic blood pressure for analysis, there was a U-shaped association. Using systolic blood pressure 110-119 mm Hg as the reference, the HRs for the systolic blood pressure categories of <110, 120-129, 130-139, and ≥140 mm Hg were 1.48 (95% CI, 1.02-2.17), 1.13 (95% CI, 0.80-1.60), 2.21 (95% CI, 1.54-3.16), and 2.91 (95% CI, 1.94-4.35), respectively. The trend was more prominent in patients with proteinuria ≥1g/day and eGFR ≥60 mL/min/1.73 m2. There was no similar trend observed in analysis of time-updated diastolic blood pressure.
In conclusion, the authors said, “In patients with IgAN, intensive blood pressure control during the treatment period may retard the kidney disease progression, but the potential risk of hypertension still needs to be considered.”