Comparison of self- and nurse-measured office blood pressure in patients with chronic kidney disease

OBJECTIVE: As blood pressure (BP) control is very important in chronic kidney disease (CKD), we investigated how office BP is influenced by the measurement circumstances and compared nonautomated self- and nurse-measured BP values. MATERIALS AND METHODS: Two hundred stage 1-5 CKD patients with scheduled visits to an outpatient clinic were randomized to either self-measured office BP (SMOBP) followed by nurse-measured office BP (NMOBP) or NMOBP followed by SMOBP. The participants had been educated to perform the self-measurement in at least one previous visit. The SMOBP and NMOBP measurement series both consisted of three recordings, and the means of the last two recordings during SMOBP and NMOBP were compared for the 174 (mean age 52.5 years) with complete BP data. RESULTS: SMOBP and NMOBP showed similar systolic (135.3 ± 16.6 vs 136.4 ± 17.4 mmHg, Δ = 1.1 mmHg, P = 0.13) and diastolic (81.5 ± 10.2 vs 82.2 ± 10.4 mmHg, Δ = 0.6 mmHg, P = 0.09) values. The change in BP from the first to the third recording was not different for SMOBP and NMOBP. In 17 patients, systolic SMOBP was ≥10 mmHg higher than NMOBP and in 28 patients systolic NMOBP exceeded SMOBP by ≥10 mmHg. The difference between systolic SMOBP and NMOBP was independent of CKD stage and the number of medications, but significantly more pronounced in patients above 60 years. CONCLUSION: In a population of CKD patients, there is no clinically relevant difference in SMOBP and NMOBP when recorded at the same visit. However, in 25% of the patients, systolic BP differs ≥10 mmHg between the two measurement modalities.