Comparison of blood pressure measurements on the bare arm, over a sleeve and over a rolled-up sleeve in the elderly

Although guidelines recommend that blood pressure (BP) should be measured on a bare arm, BP is sometimes measured over clothing in clinical settings. To assess the accuracy of BP measurements over clothing rolled up to the elbow in clinical settings. This was a cross-sectional study to a total of 186 individuals recruited from a primary care clinic and two day-care facilities between July and September 2014. Main outcome measures were BP measurements on (i) a bare arm, (ii) over the sleeve of a cardigan and (iii) over the sleeve of a cardigan rolled up to the elbow. BP was compared across measurement conditions using the paired t-test and multiple analysis of variance adjusting for age, sex, measurement order and interaction between clothing condition and measurement order. Of 186 subjects, 38.5% were male. Mean age was 74.6 years. Mean BP with a bare arm, over a sleeve and over a rolled-up sleeve was 128.9 (SD 19.1)/67.4 (10.8) mmHg, 132.8 (21.0)/72.6 (11.5) mmHg and 133.4 (21.3)/74.4 (12.1) mmHg, respectively. There were significant differences in BP between the bare arm and over a cardigan sleeve (P < 0.001) and the bare arm and over a rolled-up cardigan sleeve (P < 0.001). BP differences were significant even after adjusting for age group, sex, measurement order and interaction between clothing condition and measurement order. Although previous studies have suggested BP measurements over clothing are acceptable, our results suggest that BP should be measured on bare arms as recommended by guidelines whenever feasible.