Inaccuracy of home sphygmomanometers

Objective Home blood pressure monitoring requires a precise blood pressure measurement technique and an accurate sphygmomanometer. The oscillometric sphygmomanometers have some drawbacks including inaccuracy. The aims of this study were to assess the inaccuracy of home sphygmomanometers using a method first proposed in 2009 and to compare validated devices with other devices. Materials and methods Three hundred and eighty-two home sphygmomanometers that had been brought by individuals to the University Hospital were included in this study. This method has three stages (general evaluation, quick screening, final assessment) and sequential measurement of blood pressure is used for assessment. The devices were categorized into two groups for comparisons: validated and ‘others’. Results One hundred and fourteen (30%) of the 382 devices were validated. Final assessment showed 91 (24%) of the 382 devices to be inaccurate. Inaccuracy among the ‘others’ and wrist devices were more common than for the validated and upper arm devices (P<0.0001 for both comparisons). The categorization of upper arm devices into validated and ‘others’ showed that the validated devices were more accurate than the ‘others’ (94 vs. 79%) (P=0.002). The frequency of inaccurate and very inaccurate devices was 3% (three of 114) and 4% (four of 114) for the validated devices, respectively. Conclusion Validated and upper arm devices were more accurate than the ‘others’ and wrist devices. Validation did not guarantee individual accuracy. Active involvement of hypertension centers is required to improve the quality and reliability of home blood pressure monitoring.