Silent and clinically overt stroke in older Japanese subjects with white-coat and sustained hypertension

Objectives We investigated whether white-coat hypertension is a risk factor for stroke in relation to silent cerebral infarct (SCI) in an older Japane se population. Background It remains uncertain whether white-coat hypertension in older su bjects is a benign condition or is associated with an increased risk of str oke. Methods We studied the prognosis for stroke in 958 older Japanese subjects (147 normotensives [NT], 236 white-coat hypertensives [WCHT] and 575 sustai ned hypertensives [SHT]) in whom ambulatory blood pressure monitoring was p erformed in the absence of antihypertensive treatment. In 585 subjects (61% ), we also assessed SCI using brain magnetic resonance imaging. Results Silent cerebral infarcts were found in 36% of NT (n = 70), 42% of W CHT (n = 154), and 53% of SHT (n = 361); multiple SCIs (the presence of gre ater than or equal to2 SCIs) were found in 24% of NT, 25% of WCHT and 39% o f SHT. During a mean 42-month follow-up period, clinically overt strokes oc curred in 62 subjects (NT: three [2.0%]; WCHT: five [2.1%]; SHT: 54 [9.4%]) , with 14 fatal cases (NT: one [0.7%]; WCHT: 0 [0%]; SHT: 13 [2.3%]). A Cox regression analysis showed that age (p = 0.0001) and SHT (relative risk, [ RR] [95% confidence interval, CI]: 4.3 [1.3-14.2], p = 0.018) were independ ent stroke predictors, whereas WCHT was not significant. When we added pres ence/absence of SCI at baseline into this model, the RR (95% CI) for SCI wa s 4.6 (2.0-10.5) (p = 0.003) and that of SI-IT was 5.5 (1.8-18.9) versus WC HT (p = 0.004) and 3.8 (0.88-16.7) versus NT (p = 0.07). Conclusions In older subjects the incidence of stroke in WCHT is similar to that of NT and one-fourth the risk in SHT. Although SCI is a strong predic tor of stroke, the difference in stroke prognosis between ST-IT and WCHT wa s independent of SCI. It is clinically important to distinguish WCHT from S HT even after assessment of target organ damage in the elderly. (J Am Coll Cardiol 2001;38:238-45) (C) 2001 by the American College of Cardiology.