Does immunosuppressant medication lower blood pressure and arterial stiffness in patients with chronic kidney disease? An observational study.

Chronic kidney disease is a proinflammatory state associated with increased arterial stiffness. We hypothesized that chronic kidney disease patients on long-term immunosuppression would have lower arterial stiffness and require treatment with less antihypertensive medication compared with non-immunosuppressed patients. A total of 254 patients (97 on immunosuppression) with chronic kidney disease were recruited from specialist renal clinics. Brachial blood pressure, central aortic pressure and waveform and pulse wave velocity were measured. Age, peripheral blood pressure and pulse wave velocity increased with worsening renal function but were not different between immunosuppressed and non-immunosuppressed patients. Central systolic (P < 0.001) and pulse pressure (P = 0.003) and the number of antihypertensive medications (P < 0.001) increased with worsening renal function and were higher in non-immunosuppressed patients (P = 0.02, P = 0.004 and P < 0.001, respectively). Age, mean arterial pressure, number of antihypertensive medications and a diagnosis of diabetes were found to be independent predictors of pulse wave velocity (R(2) = 0.375; P < 0.001). In a subgroup of 30 patient pairs without diabetes mellitus and cardiovascular disease and with a proven renal diagnosis, carefully matched for age, gender, renal function and systolic pressure, the prescribed antihypertensive medication remained lower in the immunosuppressed patients compared with non-immunosuppressed patients (P = 0.04). Pulse wave velocity was lower in the immunosuppressed group (7.5 ± 1.8 vs. 8.8 ± 1.9 m s(-1); P = 0.02). This study suggests that immunosuppression might be a method of reducing blood pressure and arterial stiffness in patients with chronic kidney disease.