Nocturnal hypertension: Study finds abnormal nighttime BP levels can increase risks of stroke, heart failure

While hypertension (high blood pressure), a chronic health issue, is pretty well known, most people are likely to be unaware of nocturnal hypertension and its associated risks. In case you didn’t know, most health professionals measure blood pressure levels and make the diagnosis of hypertension based on the daytime measurements of patients. Nocturnal hypertension, a risk factor for heart disease In many cases, high blood pressure levels while sleeping go undetected, making nocturnal hypertension a disease that largely goes undetected. A study published in the Expert Review of Cardiovascular Therapy in 2009 indicates that nocturnal hypertension is a common complication of hypertension but can also often show up in those who have normal daytime blood pressure levels and go undetected for years. This study says that nocturnal hypertension causes abnormal circadian blood pressure patterns like non-dipping and reverse-dipping blood pressure, both of which are associated with increased organ damage and adverse cardiovascular outcomes. A new study published in the American Heart Association’s journal, Circulation, takes this understanding of nocturnal hypertension even further by indicating that those who suffer from high blood pressure while they sleep are at a higher risk of developing cardiovascular diseases in the future, including a high risk of stroke, coronary artery disease (CAD) and heart failure. How nocturnal hypertension affects the heart This study, conducted by researchers based at the Jichi Medical University in Japan, was a part of a larger Japan Ambulatory Blood Pressure Monitoring Prospective (JAMP) study which used the same BP monitoring device, measurement schedule and data processing approach to determine nocturnal hypertension patterns in patients. This study included 6,359 patients with at least one cardiovascular risk factor at the time of enrollment which was hypertension in most of their cases and free of any symptomatic cardiovascular disease. All the participants went through 24-hour ambulatory BP monitoring at the beginning of the study, which was followed by annual repetitions of the same 24-hour monitoring to determine if and when cardiovascular events occurred. During a mean follow-up of four to seven years, the researchers observed 306 cardiovascular events among the participants, including 119 strokes, 99 CAD and 88 cases of heart failure. Urgent need to control nocturnal hypertension They also found that nighttime high systolic BP was significantly associated with the risk of atherosclerotic cardiovascular disease and heart failure. Disrupted circadian BP rhythm due to the nighttime BP being higher than the daytime BP was also significantly associated with higher overall cardiovascular disease risks, especially when compared to those who have a normal circadian BP rhythm (where both nighttime and daytime BP are under control and within normal ranges). This study indicates that nocturnal hypertension is an independent risk factor for cardiovascular diseases and events and a very severe one at that. It also suggests that nocturnal hypertension should be better diagnosed in clinical settings and nighttime BP monitoring should be undertaken for all at-risk patients. It is also necessary, the researchers behind this study suggest, to tailor anti-hypertension therapies and medications accordingly in order to lower blood pressure levels throughout the 24-hour dosing period and not just through the day. For more information, read our article on Hypertension.  Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health.