Abstract P198: Clinic versus Out-of-Clinic Daytime Blood Pressure Among Older Adults: Data From the Jackson Heart Study
In the US, antihypertensive medication treatment decisions are primarily based on blood pressure (BP) measurements obtained in the clinic setting. The optimal systolic BP (SBP) goal for adults ≥60 years is controversial and a large difference between clinic and out-of-clinic daytime BP, a white-coat effect, may be present in older individuals. We estimated the white-coat effect and calculated the percentage of untreated and treated adults <60 and ≥60 years with elevated clinic BP (defined as SBP/diastolic BP [DBP] ≥140/90 mmHg), but non-elevated out-of-clinic daytime BP (“daytime BP”, defined as SBP/DBP <135/85 mmHg) among 257 African-American participants in the Jackson Heart Study with at least 10 daytime ambulatory BP measurements. For the overall population, the white-coat effect for SBP was 12.2 mmHg (95% confidence interval [CI]: 9.2-15.1) in older adults and 8.4 mmHg (95% CI: 5.7-11.1) in younger adults (p=0.06). After multivariable (MV) adjustment, this difference was 1.3 mmHg. Among those without diabetes or chronic kidney disease (CKD), the white coat effect for SBP was 15.2 mmHg (95% CI: 10.1-20.2) and 8.6 mmHg (95% CI: 5.0-12.3) for older and younger adults, respectively (p=0.04). After MV adjustment, this difference was 5.9 mmHg. Also, SBP ≥150 mmHg versus <150 mm Hg was associated with a larger white-coat effect in the overall population after MV adjustment. Among those without CKD or diabetes, older age and SBP ≥150 mmHg were associated with a larger white-coat effect after MV adjustment. Among younger and older participants with elevated clinic BP, the prevalence of non-elevated daytime BP was 34% (95% CI: 26%-44%) and 32% (95% CI: 24%-40%), respectively (p=0.64), in the overall population and 35% (95% CI: 24%-48%) and 43% (95% CI: 31%-56%), respectively, for those without CKD or diabetes (p=0.37). In conclusion, a large white-coat effect was present among older adults. These data suggest a role for ambulatory blood pressure monitoring in preventing potential over-treatment for hypertension among older adults.
Author Disclosures: R.M. Tanner: None. D. Shimbo: B. Research Grant; Significant; National Heart, Lung, and Blood Institute. S. Seals: None. G. Ogedegbe: B. Research Grant; Significant; National Heart, Lung, and Blood Institute. P. Muntner: B. Research Grant; Significant; Amgen, Inc.. G. Consultant/Advisory Board; Modest; Amgen, Inc..
- © 2015 by American Heart Association, Inc.