White-coat hypertension is defined as high blood pressure (BP) on clinical assessment but normal BP elsewhere or on ambulatory measurement. Autonomic dysfunction may be one of the mechanisms causing white-coat hypertension. Slowed heart rate recovery and excessive BP response during exercise test are associated with autonomic dysfunction. The purpose of this study was to determine the association between white-coat hypertension and abnormal autonomic nervous system response.

We assessed 295 patients stratified into three groups via 24hr ambulatory BP monitoring, following 2017 ACC/AHA guidelines: normal BP group, white-coat hypertension group, and a hypertension group. We analyzed medical history, blood test, echocardiography, 24hr ambulatory BP monitoring, and exercise test data.

There was no difference in basement characteristics and echocardiography among the groups. Blunted heart rate recovery of each group showed a significant difference. Control group had 0% blunted heart rate recovery, but 33.3% in white coat group and 27.6% in true hypertension group (P < 0.001). Also, in the control group, 4.5% showed excessive BP response, but 31.5% in the white coat hypertension group and 29.3% in the true hypertension group (P < 0.001). Excessive BP response during the exercise test or blunted heart rate recovery, which is an indicator of autonomic nervous system abnormality, was more common in the hypertensive group and white-coat hypertension group than in the normal BP group.

These results confirmed that white-coat hypertension has an autonomic nervous system risk. Therefore, white-coat hypertension can be a future cardiovascular risk factor.

Blood pressure variation (BPV) and metabolic syndrome is an independent risk factor for cardiovascular events. Ambulatory blood Pressure (ABP) has been shown to be more closely related to cardiovascular events in hypertensive patients than conventional office BP (OBP). Using both OBP and ABP, 4 groups of patients were identified: (1) normotensive patients (NT); (2) white coat hypertensives (WCHT); (3) masked hypertensives (MHT); and (4) sustainedhypertensives (SHT). We investigated the significance of BPV and metabolic risks of these 4 groups.

This study is a retrospective analysis of patients between January 2008 and May 2013. Echocardiography and 24 hour ABP monitoring were performed.

BMI was significantly higher in the MHT compared with the NT. There were progressive increases in fasting glucose level from NT to WCHT, MHT, and SHT.MHT and SHT had higher 24h and nighttime BPV than NT.MHT was significantly related with BMI (r = 0.139, P = 0.010), creatinine (r = 0.144, P = 0.018), fasting glucose (r = 0.128, P = 0.046), daytime systolic BPV (r = 0.130, P = 0.017), and daytime diastolic BPV (r = 0.130, P = 0.017). Dyslipidemia (r = 0.110, P = 0.043), nighttime systolic BPV (r = 0.241, P < 0.001) and nighttime diastolic BPV (r = 0.143, P = 0.009) shown correlation with SHT. In multivariate logistic regression, MHT was independently associated with Body mass index (OR 1.086, 95% CI 1.005–1.174, P = 0.038) and creatinine (OR 1.005, 95% CI 1.001–1.010, P = 0.045).

BPV and metabolic risk factors were found to be greater in MHT and SHT compared with NT and WCHT. This suggests that BPV and metabolic risks may contribute to the elevated cardiovascular risk observed in patients with MHT and SHT.