Background: End-digit preference (EDP) of blood pressure (BP) has been reported in both general hospitals and primary clinics worldwide. We aimed to observe the longitudinal changes in EDP of BP recordings in hypertension patients and to estimate the impact of hypertension treatment target (140/90 mmHg) on the EDP of BP in Chinese primary care clinics.
Participants and methods: A total of 318 898 BP readings from 16 433 hypertensive patients were obtained from the electronic health record of Xinzhuang town hospital in Shanghai from 1 January 2007, to 27 September 2011. The terminal digits of the recorded systolic blood pressure (SBP) and diastolic blood pressure (DBP) were analyzed. Zero preference was also analyzed according to the year and follow-ups, respectively.
Results: In all, 62.5% of SBP readings and 63.5% of DBP readings ended in zero. The zero preference of SBP was reduced from the 75.2% in 2007 to 55.9% in 2011. In addition, the zero preference decreased from the 78.6% at the registration to 58.7% at the 25th follow-up. Moreover, compared with other BP levels, hypertension treatment target was associated with increased preference for the eight end-digit for both SBP and DBP (P<0.001).
Conclusion: This study showed a decrease in zero EDP in hypertension patients managed in the Chinese community. The hypertension treatment target was associated with sub-target-EDP. Future efforts should focus on comprehensive education, coupled with the use of well-calibrated electronic BP monitors.