Clinical and pathological significance of circadian blood pressure rhythm change in IgA nephropathy patients with hypertension / 中华肾脏病杂志

Objective To investigate whether the clinical and pathological injury of kidney in IgA nephropathy (IgAN) patients with hypertension is associated with circadian blood pressure rhythm change, particularly with elevated nocturnal blood pressure (BP). Methods This study was a retrospective cross-sectional study. Clinic and renal histopathological injury data were obtained from 83 IgAN patients with hypertension. First, 24 h ambulatory BP monitoring (ABPM) data were analyzed. Second, all these IgAN patients were divided into two groups, elevated nocturnal BP group and nocturnal normotensive BP group, and the clinical and pathological differences between this two groups were analyzed. Third, logistic regression analysis was used to analyze the influencing factors of renal tubulointerstitial injury in IgAN patients with hypertension. At last, all these IgAN patients were divided into two groups according to the level of estimated glomerular filtration rate (eGFR), group of patients with eGFR≥60 ml·min-1·(1.73 m2)-1 and the other group with eGFR<60 ml·min-1·(1.73 m2)-1, and the 24 h ABPM data were compared. Results (1) The proportion of non-dipper circadian rhythm of BP in IgAN patients with hypertension was 79.5％. (2) Compared with nocturnal normotensive BP group, patients in elevated nocturnal BP group had significantly higher levels of 24-hour urinary protein quantity and blood uric acid (both P<0.05), and lower eGFR and urine osmotic pressure clinically (both P<0.05). Index of interstitial fibrosis and tubular atrophy was significantly higher in nocturnal normotensive BP group (P<0.05), while the proportion of glomerular ischemia lesion was not significantly different between two groups. (3) Multivariate logistic regression analysis showed that elevated nocturnal BP was an independent risk factor for severe tubulointerstitial injury of IgAN (OR=1.113, 95％CI 1.038-1.192, P=0.002). (4) Compared with the group of eGFR≥60 ml·min-1·(1.73 m2)-1, 24-hour systolic blood pressure (SBP) and diastolic blood pressure (DBP), daytime SBP and DBP, nocturnal SBP and DBP were significantly higher in group of eGFR<60 ml·min-1·(1.73 m2)-1 (all P<0.05). Conclusion The proportion of non-dipper circadian rhythm of BP in IgAN patients with hypertension is as high as 79.5％. Elevated nocturnal BP is associated with the severity of renal damage, and elevated nocturnal BP is an independent risk factor for severe tubulointerstitial injury in IgAN patients with hypertension. Therefore, 24 h ABPM should be emphasized, and elevated nocturnal BP should be well controlled to slow the progression of IgAN.

Decreased Nocturnal Blood Pressure Dipping in Patients with Periodic Limb Movements in Sleep / 수면정신생리

OBJECTIVES: Previous studies have shown that periodic limb movements in sleep (PLMS) could be one of risk factors for cardiovascular morbidity. The purpose of this study was to investigate the association between PLMS and blood pressure changes during sleep. METHODS: We analyzed data from 358 adults (176 men and 182 women) aged 18 years and older who were free from sleep apnea syndrome (Respiratory Disturbance Index 15)]. Blood pressure change patterns were compared using repeated measures analysis of variance. RESULTS: Systolic blood pressure in the high PLMI group was lower than that in the low PLMI group (p = 0.036). These results were also significant when adjusted for gender and age, but were not statistically significant when adjusted for BMI, alcohol, smoking, anti-hypertension medication use and sleep efficiency (p = 0.098). Systolic blood pressure dropped by 9.7 mm Hg in the low PLMI group, and systolic blood pressure in the high PLMI group dropped by 2.9 mm Hg. There was a significant difference in delta systolic blood pressure after sleep between the two groups in women when adjusted for age, BMI, alcohol, smoking, antihypertensive medication use and sleep efficiency (p = 0.023). CONCLUSION: PLMS was significantly associated with a decreasing pattern in nocturnal BP during sleep, and this association remained significant in women when adjusted for age, BMI, alcohol, smoking, antihypertension medication use and sleep efficiency related to blood pressure. We suggest that PLMS may be associated with cardiovascular morbidity.

The relationship between serum albumin levels and 24-h ambulatory blood pressure monitoring recordings in non-diabetic essential hypertensive patients

OBJECTIVES: The goal of this study was to evaluate the relationship between serum albumin levels and 24-hour ambulatory blood pressure monitoring (24-h ABPM) recordings in non-diabetic essential hypertensive patients. METHODS: A total of 354 patients (mean [SD] age: 55.5 [14.3] years, 50% females) with essential hypertension and 24-h ABPM recordings were included. Patient 24-h nighttime and daytime ABPM values, systolic and diastolic dipping status and average nocturnal dipping were recorded. The correlations between serum albumin levels and nocturnal systolic and diastolic dipping were evaluated, and correlates of average nocturnal systolic dipping were determined via a linear regression model. RESULTS: Overall, 73.2% of patients were determined to be non-dippers. The mean (SD) levels of serum albumin (4.2 [0.3] g/dL vs. 4.4 [0.4] g/dL, p<0.001) and the average nocturnal systolic (15.2 [4.8] mmHg vs. 0.3 [6.6] mmHg, p<0.001) and diastolic dipping (4.2 [8.6] mmHg vs. 18.9 [7.0] mmHg, p<0.001) were significantly lower in non-dippers than in dippers. A significant positive correlation was noted between serum albumin levels and both systolic (r=0.297, p<0.001) and diastolic dipping (r=0.265, p<0.001). The linear regression analysis revealed that for each one-unit increase in serum albumin, the average nocturnal dip in systolic BP increased by 0.17 mmHg (p=0.033). CONCLUSION: Our findings indicate an association between serum albumin levels and the deterioration of circadian BP rhythm among essential hypertensive patients along with the identification of a non-dipper pattern in more than two-thirds of patients. Our findings emphasize the importance of serum albumin levels, rather than urinary albumin excretion, as an independent predictor of nocturnal systolic dipping, at least in non-diabetic essential hypertensive patients with moderate proteinuria.

Relationship between homocysteine and non-dipper pattern in patients with type 2 diabetes mellitus / Relação entre a homocisteína e a condição não dipper em pacientes com diabetes melito tipo 2

OBJECTIVE: The rate of reduction of nocturnal blood pressure (NBP) is lesser than normal in patients with type 2 diabetes mellitus (type 2 DM). Hyperhomocysteinemia (HHC) disrupts vascular structure and function, no matter the underlying causes. The risk of development of vascular disease is greater in diabetic patients with hyperhomocysteinemia than in patients with normal homocystein levels. The aim of the study was to investigate whether there are differences of homocystein levels in dipper and non-dippers patients with type 2 DM. SUBJECTS AND METHODS: We compared 50 patien­ts (33 females, 17 males) with type 2 DM and 35 healthy individuals (18 females, 17 males ) in a control group. Ambulatory blood pressure monitoring (ABPM) was performed and homocysteine levels were measured in all patients. RESULTS: We found that the percentage of non-dipper pattern was 72% in patients with type 2 DM and 57% in control group. In diabetic and control individuals, homocystein levels were higher in non-dipper (respectively 13.4 ± 8.1 µmol/L and 11.8 ± 5 µmol/L) than in dipper subjects (respectively, 11.8 ± 5.8 µmol/L and 10.1 ± 4.2 µmol/L), but there was no significant difference between the two groups (respectively, p = 0.545, p = 0.294). CONCLUSION: In both groups, homocystein levels were higher in non-dipper than in dipper participants, but there was no significant difference between the groups. High homocystein levels and the non-dipper pattern increases cardiovascular risk. Therefore, the relationship between nocturnal blood pressure changes and homocystein levels should be investigated in a larger study.

OBJETIVO: A taxa de redução da pressão arterial noturna (PAN) é menor em pacientes com diabetes melito tipo 2 (DM tipo 2). A hiper-homocisteinemia (HHC) perturba a estrutura e a função vascular, independentemente das causas subjacentes. O risco de desenvolvimento de doenças vasculares é maior em pacientes diabéticos com hiper-homocisteinemia do que em pacientes com níveis normais de homocisteína. O objetivo deste estudo foi investigar se há diferenças entre os níveis de homocisteína em pacientes com DM2 em condição dipper ou não dipper. SUJEITOS E MÉTODOS: Comparamos 50 pacientes (33 mulheres, 17 homens) com DM tipo 2 e 35 indivíduos saudáveis (18 mulheres, 17 homens), usados como grupo controle. A monitorização ambulatorial da pressão arterial (MAPA) e os níveis de hemocisteína foram medidos em todos os pacientes. RESULTADOS: Observamos que a porcentagem de não dipper foi de 72% em pacientes com DM tipo 2 e 57% no grupo controle. Em indivíduos diabéticos e controle, os níveis de homocisteína foram mais altos em indivíduos não dipper (respectivamente 13,4 ± 8,1 µmol/L e 11,8 ± 5 µmol/L) do que em indivíduos dipper (respectivamente, 11,8 ± 5,8 µmol/L e 10,1 ± 4,2 µmol/L), mas não houve diferença significativa entre os dois grupos (respectivamente, p = 0,545, p = 0,294). CONCLUSÃO: Em ambos os grupos, os níveis de homocisteína foram mais altos nos indivíduos não dipper do que nos indivíduos dipper, mas não houve diferença significativa entre os grupos. Altos níveis de homocisteína e a condição não dipper aumentam o risco cardiovascular. Portanto, a relação entre as alterações da pressão arterial noturna e os níveis de homocisteína deve ser investigada em um estudo mais amplo.

Cognitive impairment and nocturnal blood pressure fall in treated elderly hypertensives

<p><b>OBJECTIVES</b>We investigated the association between the fall of nocturnal blood pressure (BP) and cognitive impairment in elderly subjects.</p><p><b>METHODS</b>The study was a cross-sectional survey of 204 elderly subjects who had no cerebrovasucular episodes. Ambulatory BP monitoring and assessments of cognitive functions using the Mini-Mental State Examination (MMSE) were performed at the subjects' homes. We classified, the subjects treated with antihypertensive drugs into three groups: non-dippers (nocturnal fall<10% of the mean day diastolic BP; n=51), normal dippers (10% to less than 20%; n=58), and extreme dippers (20% or more; n=17). The subjects not treated with antihypertensive drugs were also classified as non-dippers (n=40), normal dippers (n=24), and extreme dippers (n=14).</p><p><b>RESULTS</b>The mean age of participants was 75.2±7.2 years, and 126 (61.7%) were being treated with antihypertensive drugs. In the group of antihypertensive drug users, the number with MMSE≤23 was 30 and the adjusted odds ratio for cognitive impairment in those with an extreme dip in diastolic BP (DBP) was 4.18 (95% CI, 1.07-16.40) in reference to the normal dippers. In contrast, no association was observed between cognitive function and nocturnal BP fall in the group no using antihypertensive drugs.</p><p><b>CONCLUSIONS</b>Cognitive impairment was associated with an extreme dip in DBP in the antihypertensive drug users only. It remains to be seen whether careful monitoring of nighttime BP as well as daytime BP may reduce the risk of cognitive impairment in antihypertensive drug users.</p>

Cognitive Impairment and Nocturnal Blood Pressure Fall in Treated Elderly Hypertensives

Objectives: We investigated the association between the fall of nocturnal blood pressure (BP) and cognitive impairment in elderly subjects. Methods: The study was a cross-sectional survey of 204 elderly subjects who had no cerebrovasucular episodes. Ambulatory BP monitoring and assessments of cognitive functions using the Mini-Mental State Examination (MMSE) were performed at the subjects' homes. We classified the subjects treated with antihypertensive drugs into three groups: non-dippers (nocturnal fall <10% of the mean day diastolic BP; n=51), normal dippers (10% to less than 20%; n=58), and extreme dippers (20% or more; n=17). The subjects not treated with antihypertensive drugs were also classified as non-dippers (n=40), normal dippers (n=24), and extreme dippers (n=14). Results: The mean age of participants was 75.2±7.2 years, and 126 (61.7%) were being treated with antihypertensive drugs. In the group of antihypertensive drug users, the number with MMSE£23 was 30 and the adjusted odds ratio for cognitive impairment in those with an extreme dip in diastolic BP (DBP) was 4.18 (95% CI, 1.07−16.40) in reference to the normal dippers. In contrast, no association was observed between cognitive function and nocturnal BP fall in the group no using antihypertensive drugs. Conclusions: Cognitive impairment was associated with an extreme dip in DBP in the antihypertensive drug users only. It remains to be seen whether careful monitoring of nighttime BP as well as daytime BP may reduce the risk of cognitive impairment in antihypertensive drug users.

The factors influencing nocturnal blood pressure drop in essential hypertensives

BACKGROUND: Blood pressure is normally lower during night times than in day times. But in some people, this nocturnal blood pressure drop is decreased or absent. In essential hypertensives, absence of nocturnal blood pressure drop (the 'nondipping' pattern) has been associated with increased target organ damage and cardiovascular morbidity. Present study was intended to describe the proportion of 'nondippers' among untreated essential hypertensives in Korea and to investigate the influences of independent clinical factors on the nocturnal fall of blood pressure. METHODS: We studied 50 untreated Korean essential hypertensives who underwent 24-hour ambulatory blood pressure monitoring. Subjects with a nocturnal drop in systolic or diastolic blood pressure, or both, 10% were defined as 'dippers', the others as 'nondippers'. Their demographic and clinical characteristics were obtained through medical record and questionnaire. Above characteristics were considered to be independent variables and the dipping status, dependent. RESULTS: Thirty four percent of essential hypertensives were 'nondippers'. Nocturnal bloGd pressure drop decreased with reporting of family history of hypertension and higher 24-hour ambulatory mean b1ood pressure. Previous studies insisted on the influence of age on the dipping status, but in our study, age showed no impact on nocturnal blood pressure drop. CONCLUSION: About one third of untreated subjects with essential hypertension were observed to be nondippers. Family history of hypertension and high 24-hour ambulatory mean blood pressure significantly decreased nocturnal blood pressure drop in our study. According to the previous studies, above factors might work through affecting the normally decreased sympathetic activity during sleep time. Longitudinal studies of the influence of nondipping on the long term prognosis of hypertension and large scale studies to establish the factors influencing nocturnal blood pressure drop and their mechanisms are further needed.

Effect of Hot Spring Bathing on Nocturnal Blood Pressure at Kusatsu / 日本温泉気候物理医学会雑誌

The effect of hot spring bathing on nocturnal blood pressure was investigated in 6 normotensive young individuals at Kusatsu. Blood pressure and heart rate were measured at 1-hour intervals from 18:00 one day until 12:00 the following day. The experiments were performed on 2 consecutive days. Three subjects took a 10-minute 42°C hot-spring bath at 20:00 on the first experimental day but did not on the second experimental day. The order of experiments was inverted in the other 3 subjects. While not statistically significant, the nocturnal blood pressure on the “bathing” day tended to be decreased more than that on the control day. However, there was no difference in the heart rate. These findings may suggest possible involvement of hot spring bathing in the initiation of thrombotic diseases occurred in the morning hours at Kusatsu.