Many previous studies have reported that nighttime blood pressure (BP) provided a superior prognostic power compared to daytime BP. New European hypertension guideline has presented the recommendation of the assessment of nighttime BP using ambulatory BP monitoring [1]. In this issue of Hypertension Research, Li et al. reported that the control rate of daytime, nighttime, and morning ambulatory BP were 44.6%, 27.2% and 34.1% in 4088 Chinese treated hypertensive patients [2]. Thus, to achieve good night BP control is challenging in Asian hypertensive population.

Sleep disorder breathing (SDB), especially obstructive sleep apnea (OSA), is closely linked to increased nighttime BP. In this issue, Shimizu et al. reported that SDB severity assessed by 3% oxygen desaturation index was associated with the overnight change in xanthine oxidoreductase activity and urinary levels of 8-hydroxy-2’-deoxygyanosine in Japanese coronary artery disease patients [3]. The patients with OSA do not always increase nighttime BP. Although that study did not assess nighttime BP, future study investigating the contribution of the linkage between hypoxia and purine metabolic pathway for nighttime BP would be interesting.

Mizoguchi et al. revealed the association between gut microbiota and systemic renin-angiotensin-aldosterone system in general population [4]. Recently, gut microbiota has been acknowledged as a key player for regulating many pathogenic processes. If the research for the association between gut microbiota and nighttime BP is developed, gut microbiota may be highlighted as a new pathophysiology of increased nighttime BP.

In this issue, two interesting papers regarding non-pharmacological and pharmacological hypertensive treatment has been published. Zhang et al. reported the longitudinal association between dietary patterns and hypertension in Chinese adults [5]. The results showed that the modern pattern characterized by high intake of fruit and dairy products was inversely associated with systolic BP, while the meat pattern characterized by high intakes of poultry, organ meats and other livestock meat was associated with diastolic BP and a risk of hypertension. Previous study has also reported that urine sodium and the sodium to potassium ratio was associated with nighttime BP [6]. Sodium restriction has been recognized as an effective method in reducing nighttime BP [7]. Modern pattern of food may also have a positive impact on reducing nighttime BP. Concerning the pharmacological treatment of nighttime BP, diuretics provides a significant reduction in nighttime BP compared daytime BP [8]. Several studies have investigated the association between the use of a specific antihypertensive drugs and the risk of cancer. However, the results have been inconsistent. Lin et al. reported that there was no difference in the risk of breast cancer between the users of calcium channel blockers (CCB) and angiotensin converting enzyme inhibitors/angiotensin II receptor blockers (ARB) from Taiwan Health and Welfare Database [9]. Previous study showed that the combination of CCB with ARB significantly reduced nighttime BP compared to the combination of ARB with diuretics in Japanese nocturnal hypertension [10]. This combination is not only a mainstream of pharmacological hypertensive treatment but also non-specific treatment of increased nighttime BP.

Nighttime BP is usually measured and monitored by ambulatory BP monitoring. New devices such as a developed oscillometric device or cuffless monitoring have been introduced and validated in the clinical setting to alternative ambulatory BP monitoring [11,12,13,14]. The development of these devices could be considered as a useful to manage nighttime BP more effectively.