The effect of mountaineering on the association between blood pressure and physical activity: A new multi-sensor ambulatory blood-pressure monitoring device. The Mount Fuji Study.

It has not been fully investigated whether the response of blood pressure (BP) to activity at high altitudes differs from that at low altitudes or how temperature is involved in these differences. The author compared BP response to accelerometer measurements during mountaineering and daily living. In 15 healthy people (mean age 33 ± 6 years), a new multi-sensor ambulatory BP monitoring (ABPM) device equipped with barometer, thermometer, and accelerometer was used to measure BP responses to activity during a trip to Mt. Fuji and during daily living. Associations between physical activity (log-transformed 5-min average values of accelerometer just before each ambulatory BP) and the corresponding BP were obtained from 843 and 676 readings during the Mt. Fuji trip and daily living, respectively. All ambulatory systolic BP (SBP) parameters were significantly higher during the Mt. Fuji trip than during daily living (all p < .01). There were significant positive correlations between physical activity and corresponding BPs in both mountaineering and daily living (all p < .01), and there was an interaction between BPs and physical activity according to the two conditions (p < .01). On Mt. Fuji, multivariate regression analysis showed increased physical activity and lower temperature were associated with increased 24-h SBP and diastolic BP (DBP) (all p < .05). The goodness-of-fit values of the association between activity and 24-h SBP or DBP were improved by adding temperature to the model of both 24-h SBP and DBP. However, these associations were not found in the daily living model. BP response to activity was more pronounced during mountaineering than daily living.

New Conversion Formula Between B-Type Natriuretic Peptide and N-Terminal-Pro-B-Type Natriuretic Peptide　- Analysis From a Multicenter Study.

BACKGROUND: Although B-type natriuretic peptide (BNP) and N-terminal (NT)-proBNP are commonly used markers of heart failure, a simple conversion formula between these peptides has not yet been developed for clinical use.Methods and Results: A total of 9,394 samples were obtained from Nara Medical University, Jichi Medical University, and Osaka University. We randomly selected 70% for a derivation set to investigate a conversion formula from BNP to NT-proBNP using estimated glomerular filtration rate (eGFR) and body mass index (BMI); the remaining 30% was used as the internal validation set and we used a cohort study from Nara Medical University as an external validation set. Multivariate linear regression analysis revealed a new conversion formula: log NT-proBNP = 1.21 + 1.03 × log BNP - 0.009 × BMI - 0.007 × eGFR (r2=0.900, P<0.0001). The correlation coefficients between the actual and converted values of log NT-proBNP in the internal and external validation sets were 0.942 (P<0.0001) and 0.891 (P<0.0001), respectively. We applied this formula to samples obtained from patients administered with sacubitril/valsartan. After treatment initiation, NT-proBNP levels decreased and actual BNP levels increased. However, the calculated BNP levels decreased roughly parallel to the NT-proBNP levels. CONCLUSIONS: This new and simple conversion formula of BNP and NT-proBNP with eGFR and BMI is potentially useful in clinical practice.

Differences in exercise-induced blood pressure changes between young trained and untrained individuals.

There are no studies assessing short-term blood pressure (BP) changes induced by daily exercise load in young trained individuals. The authors enrolled 25 healthy, trained (mean age 19.7 ± 0.1 years, 36% female) and 26 healthy, untrained (mean age 20.4 ± 0.3 years, 50% female) individuals and measured BP after the Master two-step test. Among them, 42 individuals underwent echocardiography after BP measurements to assess left ventricular mass index (LVMI). The baseline systolic BP (SBP) levels of trained and untrained individuals were 122.7 ± 2.9 versus 117.4 ± 1.5 mmHg, respectively (p = .016). Trained individuals showed a significant suppression of the SBP increase soon after exercise loads and lower SBP levels at 1, 2, and 3 min after exercise loads compared with untrained individuals. The peak SBP level over the study period was also significantly lower in trained individuals than in untrained individuals: 156.4 ± 3.3 versus 183.7 ± 5.2 mmHg (p < .001). Trained individuals showed significantly higher LVMI compared with untrained individuals: 129.4 versus 101.6 g/m2 (p < .001). These findings demonstrated that trained individuals showed significant suppression of short-term BP variability in response to by daily exercise loads and prompt SBP recovery from acute exercise loads compared with untrained individuals. Our results would be useful to understand short-term BPV and LV hypertrophy induced by adaptive responses of the heart to regular exercise loads.

Correlation between B-Type Natriuretic Peptide and N-Terminal pro-B-Type Natriuretic Peptide in a Large Japanese Population at Risk of Stage A Heart Failure.

BACKGROUND: The measurements of B-type natriuretic peptide (BNP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) are useful for ruling out heart failure and as prognostic markers in not only heart failure populations but also general populations. It is not clear whether these two biomarkers are elevated in parallel or associated with demographic characteristics in large populations at risk of stage A heart failure. Here we investigated the relationship between BNP and NT-proBNP and extended the evaluation of this association to known demographic disparities in stage A heart failure. METHODS: Of 4,310 ambulatory patients, we analyzed the cases of the 3,643 (mean age 65 ± 11 years, 46$ male, and 79$ on antihypertensive medication) patients whose serum BNP and NT-proBNP levels were both measured and who had a history of and/or risk factors for cardiovascular disease from the Japan Morning Surge-Home Blood Pressure (J-HOP) Study dataset. RESULTS: The median (25th-75th percentiles) BNP and NT-proBNP values were 18.7 (9.3-38.5) pg/mL and 50.3 (25.5-97.4) pg/mL. There was a significant association between log-transformed BNP and log-transformed NT-proBNP (r = 818, p < 0.001). A multiple linear regression analysis showed that log-transformed NT-proBNP was significantly associated with log-transformed BNP (beta coefficient = 0.774, p < 0.001). When stratified by demographic characteristics, these associations remained (all p < 0.001). CONCLUSION: In a large Japanese population at risk of stage A heart failure, there was a significant association between BNP and NT-proBNP after adjustment and stratification by demographics.

Sex Differences in the Prognostic Power of Brain Natriuretic Peptide and N-Terminal Pro-Brain Natriuretic Peptide for Cardiovascular Events　- The Japan Morning Surge-Home Blood Pressure Study.

BACKGROUND: Brain natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are prognostic biomarkers. Although these 2 peptides differ with regard to biological characteristics, there are few reports on the differences between BNP and NT-proBNP with regard to cardiovascular events or according to sex.Methods and Results:Between 2005 and 2012, this study analyzed 3,610 of 4,310 Japanese outpatients (mean age, 65 years; men, n=1,664; women, n=1,947) with a history of at least one cardiovascular event who were recruited to the Japan Morning Surge-Home Blood Pressure Study. During an average 4-year follow-up, there were 129 cardiovascular events. Both median BNP (21.1 pg/mL; IQR, 10.9-40.6 pg/mL vs. 16.2 pg/mL, IQR, 7.2-36.2 pg/mL, P<0.001) and median NT-proBNP (54.7 pg/mL; IQR, 30.2-102.6 pg/mL vs. 44.9 pg/mL, IQR, 20.7-92.6 pg/mL, P<0.001) were significantly higher in women than in men. A 1-SD increment in log-transformed BNP (hazard ratio [HR], 2.18; 95% CI: 1.53-3.10) and NT-proBNP (HR, 2.39; 95% CI: 1.73-3.31) was associated with a significant increase in cardiovascular events in women; in men, only NT-proBNP showed this association. There was an interaction between log-transformed BNP (P=0.007) or NT-proBNP (P=0.001) and cardiovascular events according to sex. CONCLUSIONS: Both BNP and NT-proBNP predicted cardiovascular outcomes in a large Japanese clinical population. BNP and NT-proBNP were significantly stronger predictors in women than in men.

Three novel BMPR2 mutations associated with advanced pulmonary arterial hypertension.

Mutations in the bone morphogenetic protein receptor type II (BMPR2) gene may result in the development of pulmonary arterial hypertension (PAH). However, the contribution of disease-causing mutations to the disease characteristics and responsiveness to recent treatment remains to be elucidated. We report three Japanese cases of advanced PAH with novel BMPR2 mutations, including two splicing mutations (IVS8-6_7delTTinsA and IVS9-2A>G) and one deletion (c.1279delG) mutation.