Prevalence and characteristics of isolated nocturnal hypertension in the general population

Abstract

Background/Aims: Ascertaining the prevalence of isolated nocturnal hypertension (INHT) in the general population and identifying the characteristics of patients with INHT may be important to determine patients who should receive 24- hour ambulatory blood pressure (BP) measurements. This study aimed to evaluate the prevalence and characteristics of INHT in the general population.Methods: Of 1,128 participants (aged 20 to 70 years), we analyzed 823 who had valid 24-hour ambulatory BP measurements and were not on antihypertensive drug treatment.Results: The prevalence of INHT in the study was 22.8%. Individuals with INHT had a higher office, 24-hour, and daytime and nighttime ambulatory systolic and diastolic BPs compared to individuals with sustained day-night normotension. INHT was more prevalent in individuals with masked hypertension (MH) than in those with sustained hypertension (59.8% vs. 15.6%, p < 0.001). Among individuals with INHT, 92.6% had MH. Among individuals with office BP-based prehypertension, 34.5% had both INHT and MH. The prevalence of INHT was highest in individuals with office BP-based prehypertension. INHT was an independent determinant of MH after adjustment for age, sex, body mass index, diabetes, low-density-lipoprotein cholesterol, 24-hour systolic and diastolic BP, systolic and diastolic BP dipping, and systolic and diastolic BP non-dipping.Conclusions: The present study showed that INHT is not uncommon and is a major determinant of MH. Our findings strongly suggest the use of 24-hour ambulatory BP measurement for individuals within the prehypertension range of office BP owing to the high prevalence of INHT and MH in this population.

Isolated nocturnal hypertension in relation to host and environmental factors and clock genes

“… 5 In a recent report from a Korean general population including 823 participants, INH was observed in 22.8% of patients, among whom 92.6% had normal office BP. 3 Compared to normotensive participants, the INH patients had an older age, greater body mass index, and higher levels of serum cholesterol and plasma glucose, and serum creatinine. INH was prevalent in patients with chronic kidney disease and sleep apnea.…”

“…Although the pathophysiological pathways of INH remain incompletely understood, it is generally accepted that several mechanisms related to nocturnal hypertension might be involved, including activated sympathetic and renin‐angiotensin systems, disturbed water and sodium metabolism, decreased baroreflex sensitivity, and insulin resistance. 15 These mechanisms, at least in part, explain why the prevalence of INH varied between populations of different characteristics, 1 , 3 , 4 , 5 , 6 and was common in patients complicated with sleep‐related disorders, chronic kidney disease, diabetes mellitus, and metabolic syndrome. 2 , 8 , 9 , 22 …”

“…6 In 428 Saudi patients who were referred to a hypertension clinic, INH was observed in 21%, and was more prevalent in masked hypertension versus sustained hypertension (70% vs 30%, P < .001) and in untreated versus treated patients (29% vs 18.7%, P < .05). 5 15 These mechanisms, at least in part, explain why the prevalence of INH varied between populations of different characteristics, 1,[3][4][5][6] and was common in patients complicated with sleep-related disorders, chronic kidney disease, diabetes mellitus, and metabolic syndrome. 2,8,9,22 Our present findings that INH patients had a faster nighttime heart rate than normotensive persons were consistent with the results of the above-mentioned reports.…”

“…1 Subsequent investigations revealed that INH was prevalent (∼10-20%) in east Asians, Blacks, Arabs, and South Americans, as well as in children and adult patients with chronic kidney diseases or diabetes mellitus. [2][3][4][5][6][7][8][9] INH was associated with left ventricular hypertrophy, arterial stiffness and impaired renal function, and with increased risks of all-cause mortality, cardiovascular complications and renal events. [10][11][12][13][14] Therefore, INH is not an innocent condition.…”

Prevalence and Characteristics of Isolated Nocturnal Hypertension and Masked Nocturnal Hypertension in a Tertiary Hospital in the City of Buenos Aires

“…Of note, masked nocturnal hypertension (MNH), i.e., controlled office BP with INH, is a subtype of masked hypertension [ 11 ], more difficult to detect, and insufficiently studied both in treated and untreated subjects.…”