Faculty Bibliography

BACKGROUND: The white coat effect (defined as the difference between blood pressure [BP] measurements taken at the physician's office and those taken outside the office) is an important determinant of misdiagnosis of hypertension, but little is known about the mechanisms underlying this phenomenon. We tested the hypothesis that the white coat effect may be a conditioned response as opposed to a manifestation of general anxiety. METHODS: A total of 238 patients in a hypertension clinic wore ambulatory blood pressure monitors on 3 separate days 1 month apart. At each clinic visit, BP readings were manually triggered in the waiting area and the examination room (in the presence and absence of the physician) and were compared with the mercury sphygmomanometer readings taken by the physician in the examination room. Patients completed trait and state anxiety measures before and after each BP assessment. RESULTS: A total of 35% of the sample was normotensive, and 9%, 37%, and 19% had white coat, sustained, and masked hypertension, respectively. The diagnostic category was associated with the state anxiety measure (F(3,237) = 6.4, P < .001) but not with the trait anxiety measure. Patients with white coat hypertension had significantly higher state anxiety scores (t = 2.67, P < .01), with the greatest difference reported during the physician measurement. The same pattern was observed for BP changes, which generally paralleled the changes in state anxiety (t = 4.86, P < .002 for systolic BP; t = 3.51, P < .002 for diastolic BP). CONCLUSIONS: These findings support our hypothesis that the white coat effect is a conditioned response. The BP measurements taken by physicians appear to exacerbate the white coat effect more than other means. This problem could be addressed with uniform use of automated BP devices in office settings

The traditional reliance on blood pressure (BP) measurement in the medical setting misses a significant number of individuals with masked hypertension, who have normal clinic BP but persistently high daytime BP when measured out of the office. We suggest that masked hypertension may be a precursor of clinically recognized sustained hypertension and is associated with increased cardiovascular risk compared with consistent normotension. We discuss factors that may contribute to clinic-daytime BP differences as well as the changing relationship between these two measures over time. Anxiety at the time of BP measurement and having been diagnosed as hypertensive appear to be two possible mechanisms. The identification of individuals with masked hypertension is of great clinical importance and requires out-of-office BP screening. Ambulatory BP monitoring is the best established technique for doing this, but home monitoring may be applicable in the future

OBJECTIVE: Distress and low perceived social support were examined as indicators of psychosocial vulnerability in patients about to undergo heart surgery. Design: A total of 550 study patients underwent heart surgeries, including bypass grafting and valve procedures. Psychosocial interviews were conducted about five days before surgery, and biomedical data were obtained from hospital records. MAIN OUTCOME MEASURES: Sociodemographic, personality, religious, and biomedical factors were evaluated as predictors of psychosocial vulnerability, and all five sets of variables were evaluated as contributors to hospital length of stay (LOS). RESULTS: Patients scoring higher on one or more indicator of presurgical psychosocial vulnerability were younger, more likely to be female, less likely to be married, less well educated, lower in dispositional optimism, higher in trait anger, and lower in religiousness. Older age, depression, low support, and low trait anger each showed an independent, prospective association with greater LOS, and several other predictors had prospective relationships with LOS that were statistically mediated by depression or perceived support. CONCLUSION: Evidence that multiple psychosocial factors may influence adaptation to heart surgery has implications for understanding and ameliorating presurgical distress and for improving postsurgical recovery

BACKGROUND: The white coat effect can lead to overdiagnosis of hypertension and unnecessary pharmacologic treatment. Mechanisms underlying the white coat effect remain poorly understood but are critical to improving the accuracy of clinic blood pressure measurement. PURPOSE: This study investigated whether perceived hypertension status was associated with state anxiety levels during a clinic visit and the magnitude of the white coat effect, independent of true blood pressure status. METHODS: This observational study included 214 normotensive and mildly hypertensive participants who were 18 to 80 years old, had no cardiac history, and were willing to discontinue antihypertensive medications for 8 weeks. Participants underwent 36 hr ambulatory blood pressure monitoring and physician blood pressure measurement. Outcome measures were state anxiety reported during the clinic visit and the white coat effect. RESULTS: An analysis of covariance indicated that participants who perceived themselves as hypertensive reported greater state anxiety (p<.001) and showed larger white coat effects (ps<.01) compared with those who perceived themselves as normotensive. True hypertension status based on ambulatory blood pressure was not related to either outcome. Anxiety accounted for approximately 19% of the association between perceived hypertension status and the white coat effect. CONCLUSIONS: These findings suggest that the perception of being hypertensive is associated with greater anxiety during clinic blood pressure measurement and a larger white coat effect, independent of the true blood pressure level. Anxiety appears to be a mechanism by which perceived hypertension status contributes to the white coat effect

BACKGROUND: Home blood pressure (HBP) monitoring plays an increasingly important role in the diagnosis and treatment of hypertension. We evaluated the independent value of HBP compared with ambulatory blood pressure (ABP) and office blood pressure (OBP) in the prediction of cardiovascular end-organ damage in normotensive subjects and untreated patients with mild hypertension. METHODS: One hundred sixty-three subjects underwent measurements of OBP, HBP, ABP, and echocardiography. A physician using a mercury-column sphygmomanometer performed three OBP measurements. The ABP was recorded using a noninvasive ambulatory monitor (mean, 35.4 awake readings per subject). Participants took HBP readings with an automatic, oscillometric device over a 10-week period (mean, 277.9 readings per subject). The left-ventricular mass index (LVMI) was calculated from measurements obtained from two-dimensionally guided M-mode or linear tracings on echocardiography. RESULTS: For systolic and diastolic blood pressures (SBP/DBP), the correlation coefficients of the LVMI with OBP, awake ABP, and HBP were 0.29/0.27, 0.41/0.26, and 0.47/0.35, respectively (all P < .01). In a multivariate regression analysis in which age, sex, body mass index, OBP, awake ABP, and HBP were included, only age, sex, and HBP were significant predictors of LVMI. When only the first 12 home readings were used, the superiority of HBP was no longer evident. CONCLUSIONS: In contrast to OBP and ABP, HBP measurements, when averaged over a 10-week period, are independently related to LVMI. The HBP adds prognostic information over and above OBP and ABP in the prediction of cardiovascular end-organ damage, but this relationship appears to depend on the number of readings taken