White Coat Effect: Is It Because of the Hospital Setting, or Is It Physician-Induced?

White coat hypertension (WCH) patients are those individuals who have high blood pressure (BP) in the medical environment but are normal during their daily activities. White coat hypertensive patients with normal daytime ambulatory blood pressure monitoring (ABPM) rapidly progress to sustained hypertension. WCH is mainly treated with non-pharmacological methods. Alpha-1 agonists and beta blockers are logical treatment choices for patients with fixed hypertension with the White Coat Effect (WCE). Masked hypertension patients are those individuals who have normal values at the doctor's office but elevated BP at home or during 24-hour ABPM (24-hour or daytime). ABPM is a more practical and reliable method for detecting patients with WCH.

This observational study was conducted at Dayanand Medical College & Hospital, Ludhiana, over the course of one year (December 2015 to November 2016). The primary objective of the study was to determine whether there was a difference in blood pressure readings between the home setting and the hospital setting. The secondary objective was to determine whether the difference, if present, between the hospital and home readings was due to the hospital setting, physician presence, or a combination of both. Patients with stage 1 hypertension were included in the study, irrespective of antihypertensive treatment. Patients with ischemic heart disease, chronic liver failure, and chronic kidney disease who could not follow protocol instructions were excluded.

In our study, the mean age of patients was 53.91±12.86 years. The patient's mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) readings at the hospital were higher than their home readings (p-0.012; p-0.001, respectively). Mean hospital SBP and DBP readings recorded by the physician were higher than readings recorded by patients alone at home (p-0.002; p-0.014, respectively) and alone at the hospital (p-0.004; p-0.001, respectively). BP readings taken by the physician with a manual sphygmomanometer were significantly lower than those taken with a digital sphygmomanometer by patients and physicians in all settings (p<0.05). The mean rise in BP was significant in both the physician's presence and the hospital environment (p<0.05 for both), and this rise was more significantly associated with the hospital effect than the physician effect (p<0.05).

Misdiagnosis of hypertension results in inappropriate prescription and overuse of antihypertensive medications for individuals who are not persistently hypertensive. So it is very important to rule out WCH in both the hospital setting and the physician's presence, more precisely by ABPM. WCH can be diagnosed with regular BP monitoring by a digital sphygmomanometer at home.