[Ultra-long-term follow-up of renal denervation in patients with resistant hypertension and mild chronic kidney disease].

Objective: To investigate the ultra-long-term antihypertensive efficacy, safety, major adverse events, and survival benefits of renal denervation (RDN) in patients with resistant hypertension (rHTN) and mild chronic kidney disease (CKD). Methods: This real-world, single-center retrospective study enrolled patients with rHTN and mild CKD who underwent RDN at Tianjin First Central Hospital between October 2011 and June 2016. Office blood pressure, home self-measured blood pressure, 24-hour ambulatory blood pressure, serum creatinine, estimated glomerular filtration rate, and urine albumin-to-creatinine ratio were collected at baseline and at 1, 5, and 13 years post-RDN. The total daily defined dose of antihypertensive medications at 13 years post-RDN was recorded, along with endpoint events during follow-up, including cardiovascular death, all-cause death, hospitalization for heart failure, myocardial infarction, and stroke. Patients were stratified according to CKD stage (G1-G2 vs. G3a) and baseline systolic blood pressure (mild-to-moderate vs. severe hypertension), and follow-up data were compared across subgroups. Results: A total of 40 patients were included, aged (51±15) years, including 26 (65%) males. At the 13-year follow-up, office systolic blood pressure (SBP) and diastolic blood pressure (DBP) decreased by (-32±20) mmHg and (-15±14) mmHg (1 mmHg=0.133 kPa), respectively; reductions in home self-measured blood pressure (SBP: (-25±14) mmHg, DBP: (-10±11) mmHg) and 24-hour ambulatory blood pressure (SBP: (-16±9 mmHg, DBP: (-10±6) mmHg) were also observed, alongside a reduction in the total daily defined dose of antihypertensive medications by (1.1±0.9) compared to baseline. Renal function assessments showed no significant differences at 13 years versus baseline in serum creatinine ((105±51) μmol/L vs. (96±22) μmol/L), estimated glomerular filtration rate ((72±22) ml·min-1·1.73 m-2 vs. (78±17) ml·min-1·1.73 m-2), or urine albumin-to-creatinine ratio ((101±86) mg/g vs. (127±82) mg/g) (all P>0.05). All-cause and cardiovascular mortality rates during follow-up were 13% (5/40) and 8% (3/40), respectively. Subgroup analysis results showed that, although CKD G1-G2 patients had smaller reductions in office SBP ((-31±20) mmHg vs. (-34±19) mmHg) and DBP ((-13±10) mmHg vs. (-25±18) mmHg) compared to G3a patients at 13 years, intergroup differences were not significant (all P>0.05). In contrast, severe hypertension subgroup exhibited greater reductions in office SBP ((-55±13) mmHg vs. (-20±10) mmHg) and DBP ((-24±17) mmHg vs. (-13±10) mmHg) versus mild-to-moderate hypertension subgroup (all P<0.05). Conclusion: RDN demonstrates sustained antihypertensive efficacy with favorable renal safety in rHTN patients with mild CKD. Patients with higher baseline systolic blood pressure may exhibit better responsiveness to RDN.