Relationship between the behavior change model and salt intake in hypertensive patients: a single non-specialized hypertension clinic prospective observational study.

We investigated whether changes in salt reduction readiness are associated with changes in estimated daily salt intake and blood pressure (BP). We divided 86 hypertensive patients into groups with high and low readiness for salt-reducing behavior [an up (UP) and a down (DN) groups, respectively] based on the transtheoretical model (TTM) over a 12-month observation period. We then investigated the relationships between changes in the TTM stage and changes in daily salt intake and BP over 12 months. The patients in the UP group had significantly increased urine potassium concentrations (from 51.2 ±â€…23.3 mEq/L at baseline to 56.9 ±â€…25.5 mEq/L at 12 months; P  = 0.048) and significantly decreased estimated 24-h urinary salt excretion (from 9.7 ±â€…2.9 g/day at baseline to 8.4 ±â€…2.8 g/day at 12 months; P  = 0.045). In addition, they also had significantly lower changes in urine sodium concentration (-13.1 ±â€…46.1 vs. -6.6 ±â€…59.7 mEq/L; P  = 0.048), significantly increased changes in urine potassium concentration (5.7 ±â€…20.1 vs. -4.8 ±â€…28.6 mEq/L; P  = 0.030), and significantly decreased changes in estimated 24-h urinary salt excretion (-1.3 ±â€…2.6 vs. -0.1 ±â€…2.6 g/day; P  = 0.045) compared with patients in the DN group. However, their home BP did not improve over 12 months. The hypertensive patients who increased their readiness or maintained a high readiness for salt reduction over 12 months showed a significant increase in daily potassium intake and significant decrease in daily salt intake.

Overtime work is related to nonrestorative sleep independently of short sleep time among a Japanese occupational population.

OBJECTIVE: The symptoms of insomnia are defined as difficulty falling asleep, difficulty staying asleep, and early awakening. Although also a symptom of insomnia, nonrestorative sleep (NRS) is clearly more associated with objective indices than other insomnia symptoms. However, the link between NRS and overtime work duration is poorly understood. METHODS: The results of a single year's medical examinations were investigated for 26,144 Japanese office workers who were 30 to 59 years old. NRS status and lifestyle were collected through a computer-assisted medical interview. The subjects were asked about the presence or absence of NRS and their lifestyles in the most recent two to three months. The subjects were asked about their sleep times and average overtime durations per month (< 20 h/month, ≥ 20 but < 40 h/month, ≥ 40 but < 60 h/month, and ≥ 60 h/month). The relationships between NRS and overtime work duration adjusted for sleep time were also analyzed. RESULTS: The proportion of subjects with NRS showed a stepwise increase as overtime work hours increased. A logistic regression analysis was performed using NRS as an objective variable. The multivariate analysis demonstrated that overtime work duration (OR, 1.13; 95% CI 1.10-1.17; P < 0.001; per one-category increase) was an independent determinant of NRS. CONCLUSION: For office workers, long hours of overtime work increased the NRS prevalence at any sleep duration.

Relationship between nonrestorative sleep and heartburn among a Japanese occupational population.

BACKGROUND: Nonrestorative sleep (NRS) is a symptom of insomnia and is clearly more associated with objective indices than other insomnia symptoms. Gastroesophageal reflux disease (GERD) and insomnia are known to be strongly related. However, the link between NRS and heartburn, a main symptom of GERD, is poorly understood. Therefore, the relationships between them were investigated in addition to sleep duration. METHODS: The results of a single year's medical examinations were investigated for 29,475 Japanese active office workers who were 20 to 59 years old. NRS and heartburn were investigated in a medical interview using a personal computer. The relationships between NRS and heartburn in addition to sleep duration were also analyzed. RESULTS: The subjects were 46.6 ± 8.7 years old (mean ± SD) and 27% and 13% of them had NRS and heartburn, respectively. The presence of NRS together with a sleep duration of ≤ 5, 6, 7 or ≥ 8 hours was an independent comorbid factor for heartburn compared with the absence of NRS together with a sleep duration of seven hours (reference; odds ratio [OR], 2.38; 95% confidence interval [CI], 2.11-2.69, OR, 2.44; 95% CI, 2.16-2.76, OR, 2.33; 95% CI, 1.94-2.79; and OR, 1.72; 95% CI, 1.14-2.52). The absence of NRS together with a sleep duration of ≤ 5 hours was also an independent comorbid factor for heartburn compared with the reference (OR, 1.20; 95% CI, 1.05-1.37). CONCLUSIONS: NRS in active workers may contribute to heartburn comorbidity despite the sleep duration as in other workers without NRS.

Relationship between nonrestorative sleep with short sleep duration and diabetes mellitus comorbid among a Japanese occupational population.

Objective: Nonrestorative sleep (NRS) is one of the symptoms of insomnia and is clearly more associated with objective indices, such as sleep stability, sleep fragmentation, and inflammatory responses, than other insomnia symptoms. However, the link between NRS and diabetes mellitus is poorly understood. Therefore, the prevalence of NRS in workers and the relationships between NRS and diabetes were investigated. Methods: The results of a single year's medical examinations were investigated for 26,144 Japanese active office workers who were 30 to 59 years old. NRS was investigated using a personal computer in a medical interview. Furthermore, the relationships between NRS and diabetes comorbidity in addition to sleep duration were also analyzed. Results: The mean age of the subjects was 47.9 ± 7.3 years old, and the proportion of subjects with NRS was 26%. The presence of NRS together with a sleep duration ≤ 5 h or a sleep duration of 6 h was an independent comorbid factor for diabetes compared with the absence of NRS together with a sleep duration of 7 h (odds ratio [OR] 1.34; 95% confidence interval [CI] 1.14-1.58; P < 0.001; and OR 1.25; 95% CI 1.04-1.48; P = 0.015). Conclusion: NRS in active workers may contribute to the development of diabetes even if the workers have the same short sleep durations as other workers without NRS.

Relationship between salt reduction readiness and salt intake in hypertensive patients: a single nonspecialized hypertension clinic case study.

This is the first report about the association of readiness for salt reduction with daily salt intake or the salt check sheet score in hypertensive patients at a nonspecialized hypertension clinic. We investigated whether salt reduction readiness as evaluated based on the transtheoretical model (TTM) is associated with estimated daily salt intake or the salt check sheet score. The TTM allows evaluators to easily assess a subject's level of readiness for health-related according to five stages. There was no significant relationship between the TTM stages and estimated daily salt intake. A significant correlation was found between the TTM stages and salt check sheet scores (ρ = -0.409; P < 0.001). When providing salt reduction guidance to hypertensive patients, it is effective for healthcare professionals to use repeated urine tests and salt check sheets to take a salt reduction approach according to the level of readiness of the patients.

Determining the Relationship between Triglycerides and Arterial Stiffness in Cardiovascular Risk Patients Without Low-Density Lipoprotein Cholesterol-Lowering Therapy.

Data examining the relationship between arterial stiffness and triglyceride (TG) and other cardiovascular risk factors have remained to be sparse.Of the 5,109 patients with any cardiovascular risk factors in the Cardiovascular Prognostic Coupling Study in Japan (the Coupling Registry), the data of 1,534 patients who had no history of cardiovascular disease and were without low-density lipoprotein cholesterol (LDL-C) -lowering therapy (average age 67.9 ± 12.0 years, 55% males) were analyzed. Arterial stiffness was evaluated using the cardio-ankle vascular index (CAVI). Among the clinical and behavioral cardiovascular risk factors, the significant factors that constituted the CAVI value were smoking, diabetes, lower high-density lipoprotein cholesterol, and higher TG. After adjustment for age, sex, and body mass index (BMI), only TG (odds ratio [OR] per 1 standard deviation, 1.26 [95% confidence interval, 1.12-1.44]) and diabetes (OR, 1.52 [1.22-1.90]) were found to be associated with a risk of higher CAVI (≥ 9.0). TG (C-statistic, 0.80 [0.78-0.82]; P = 0.040) and diabetes (C-statistic, 0.80 [0.78-0.82]; P = 0.038) significantly improved the discrimination of the risk of a higher CAVI beyond the model that included age, sex, and BMI.TG was associated with a risk of arterial stiffness, and its contribution was slight but almost the same as that of diabetes among patients who had cardiovascular risk without a history of cardiovascular disease and LDL-C-lowering therapy.

Validation of Self-Monitoring Devices Supporting Sodium Intake Reduction: An Experimental Feeding Study Using Standardized Low-Salt and High-Salt Meals among Healthy Japanese Volunteers.

INTRODUCTION: Although several approaches for approximating daily Na intake and the Na/K ratio using casual urine are available, the most useful method remains unclear during daily practice and at home. METHODS: Twenty-seven participants measured their casual urinary Na/K ratio repeatedly using a Na/K ratio monitor and also measured overnight urine once daily using a monitoring device which delivers on-site feedback to estimate their salt intake under unrestricted, low-salt (LS) (6 g/day), and high-salt (HS) (12 g/day) diets. RESULTS: The monitoring method utilizing overnight urine to estimate daily Na remained insensitive, resulting in significant overestimation during the LS diet and underestimation during the HS diet periods; estimated salt intake during the LS and HS diet periods plateaued at 7-8 g/day and 9-10 g/day within 3 day; mean estimated salt intake was 11.3 g/day, 7.9 g/day, and 9.8 g/day on the last day of the unrestricted, LS, and HS diets; the coefficient of variation (CV) of the estimated Na intake was 0.23 and 0.17 in the latter half of the low- and high-salt diet periods, respectively. The mean urinary Na/K molar ratio was 5.6, 2.5, and 5.3 on the last day of the unrestricted, LS, and HS diets; the CV of the daily mean Na/K ratio was 0.41 and 0.36 in the latter half of the LS and HS diet periods, respectively. The urinary Na/K ratio during the LS and HS diet periods plateaued within 2 days. The monitoring method based on the daily mean of the casual urinary Na/K ratio reflected the actual change in Na intake, and the estimated value tracked the actual changes in salt intake with smaller difference than the overnight urine estimates when using the estimation coefficient set at 2; estimated salt intake during the LS and HS diet periods plateaued at 5-6 g/day and 10-12 g/day within 2-3 day; mean estimated salt intake was 11.0 g/day, 5.7 g/day, and 10.7 g/day on the last day of the unrestricted, LS, and HS diets, respectively. DISCUSSION/CONCLUSION: Estimates of daily Na intake derived from overnight urine may remain insensitive during dietary interventions. The urinary Na/K ratio reflects the actual change in Na intake during dietary modification and may serve as a practical marker, particularly during short-term interventions. Conversion from the urinary Na/K ratio to estimated salt intake may be useful, if the coefficient was set appropriate by further investigations.

Visceral Fat Area by Abdominal Bioelectrical Impedance Analysis as a Risk of Obstructive Sleep Apnea.

This is the first study to evaluate directly visceral fat area (VFA) using a visceral fat (VF) meter by the abdominal bioelectrical impedance analysis (A-BIA) method in obstructive sleep apnea (OSA) patients diagnosed with polysomnography (PSG). The purpose of this study is to clarify (1) whether VFA measurement using a VF meter by the A-BIA method is possible even in a private clinic without burdening patients and staff and (2) how much VFA affects OSA compared to body mass index (BMI). Even without a computed tomography scan, which is the gold standard for VFA measurement, a VF meter could analyze patients by the A-BIA method and easily measure VFA. Therefore, it could be used safely even in a private sleep clinic, with very little burden on the patients and the medical staff. We investigated the association between OSA and VFA in 133 OSA patients. Multiple regression analysis revealed that VFA (ß = 0.28; P = 0.020) was a stronger coexisting factor for OSA than age, male gender, or BMI (ß = 0.26; P = 0.032) in all OSA patients. In the OSA patients with VF accumulation, only VFA was a significant component of OSA severity (ß = 0.36; P = 0.006). The A-BIA method instrument could become a useful device for the evaluation of VF accumulation in OSA patients in private sleep clinics. VF accumulation should be recognized as an important risk factor as well as a known risk factor for OSA.

Relationship between Snoring and Lifestyle-related Diseases among a Japanese Occupational Population.

Objective Snoring is a common physical condition in active workers. However, the link between snoring and health problems is poorly understood. Therefore, the prevalence of snoring in Japanese workers and the relationships between snoring and lifestyle-related diseases were investigated. Methods This was a retrospective, single-center, cross-sectional study. The results of a single year's medical examinations were investigated for 25,141 Japanese active office workers 20 to 59 years old. The presence and duration of snoring were investigated using a personal computer at a medical interview before the medical checkup. The snoring frequency was investigated for each gender. In addition, the relationships between snoring and hypertension, diabetes, and dyslipidemia were also analyzed. Results Men (21,774) were a mean 46±6 years old with a snoring prevalence of 43%. Women (3,367) were a mean 46±6 years old with a snoring prevalence of 20%. In men, snoring was an independent comorbid factor of hypertension and dyslipidemia. In particular, a long snoring vintage (multiple years) was an independent comorbid factor for hypertension [odds ratio (OR), 1.14; 95% confidence interval (CI), 1.05-1.24; p=0.002; and OR, 1.20; 95% CI, 1.07-1.34; p=0.001]. In women, snoring was not an independent comorbid factor for lifestyle-related diseases when adjusted for the age and body mass index. Conclusion Snoring was shown to be a frequent pathophysiology in active workers. It was a health indicator for active workers, and especially in men, intervention for snoring may reduce the risk of developing lifestyle-related diseases.

Age-related difference of the association of cardiovascular risk factors with the cardio-ankle vascular index in the Cardiovascular Prognostic Coupling Study in Japan (the Coupling Registry).

The value of the cardio-ankle vascular index (CAVI) increases with age. All large-scale studies of the CAVI have investigated patients <80 years old. Thus, the clinical characteristics of high CAVI in patients aged 80 or more remain unclear. Therefore, we investigated (1) the CAVI in very elderly patients and (2) the determinants of a high CAVI in high-risk patients, including very elderly patients. The Cardiovascular Prognostic Coupling Study in Japan (Coupling Registry) is a prospective observational study of Japanese outpatients with any cardiovascular risk factors. We enrolled 5109 patients from 30 institutions (average age 68.7 ± 11.4 years, 52.4% males). We investigated the determinants of the CAVI by separating the patients into three groups: 970 middle-aged (<60 years), 3252 elderly (60-79 years), and 887 very elderly (≥80 years) patients. The CAVI values of the males were significantly higher those of the females in all age groups (<60 years: 7.81 ± 1.11 vs. 7.38 ± 0.99, P < .001; 60-79 years: 9.20 ± 1.29 vs. 8.66 ± 1.07, P < .001; ≥80 years: 10.26 ± 1.39 vs. 9.51 ± 1.12, P < .001). In all age groups, the CAVI of the patients with diabetes/glucose tolerance disorder was higher than that of the patients without diabetes/glucose tolerance disorder (<60 years: 7.82 ± 1.22 vs 7.58 ± 1.03, P = .002; 60-79 years: 9.23 ± 1.20 vs 8.78 ± 1.19, P < .001; ≥80 years: 10.04 ± 1.24 vs 9.75 ± 1.32, P = .002). The determinants of the CAVI in these very elderly patients were age, male sex, low BMI, and mean blood pressure. Diabetes/glucose tolerance disorder and glucose were independently associated with the CAVI in the patients aged <60 years and 60-79 years, but not in those aged ≥80 years after adjusting for other covariates.

Rationale, design, and baseline characteristics of the Cardiovascular Prognostic COUPLING Study in Japan (the COUPLING Registry).

Vascular biomarkers, including the cardio-ankle vascular index (CAVI), are increasingly being recognized as important indicators of cardiovascular risk. CAVI has been shown to have good discriminative ability for detecting new-onset hypertension, but results of studies investigating cardiovascular risk prediction are inconsistent. Furthermore, there is a lack of data on the prognostic value of changes in CAVI over time. The Cardiovascular Prognostic Coupling study was designed to determine the impact of baseline CAVI and changes in CAVI on cardiovascular events in a Japanese cohort. The design of the ongoing, multicenter, prospective, observational registry and baseline characteristics of the enrolled population are reported. Eligible consecutive patients were aged ≥30 years, had ≥1 cardiovascular risk factor, and were being treated according to relevant Japanese guidelines. The primary outcome is time to onset of a major cardiovascular event (a composite of cerebral infarction, cerebral hemorrhage, subarachnoid hemorrhage, stroke of unknown etiology, myocardial infarction, cardiovascular intervention for angina pectoris, and sudden death). Screening and enrollment occurred over a period of 3 years, followed by ≥7 years of follow-up, with CAVI determined annually. A total of 5279 patients were registered, of whom 5109 had baseline data available and will be included in future analyses. Mean CAVI at baseline was 8.8 ± 1.4. The proportion of patients with CAVI of <8, 8-10 or >10 was 25.3%, 57.0%, and 17.7%, respectively. Data from this registry should provide information on the significance of baseline CAVI and change in CAVI as indicators of cardiovascular prognosis in a representative patient population.

The Relationship Between Premature Ventricular Contractions and Lifestyle-Related Habits among the Japanese Working Population (FUJITSU Cardiovascular and Respiratory Observational Study-1; FACT-1).

BACKGROUND: Premature ventricular contractions (PVCs) are often found in healthy workers at medical checkups. In this study, we aimed to investigate the frequency of PVCs recorded during medical checkups in Japanese office workers without heart disease or other known contributing factors. METHODS: Participants in this study were 17,641 office workers, who underwent an electrocardiogram examination during a regular medical checkup between April 1 2015 and March 31 2016 and had no known heart disease. The frequency of PVCs was recorded. Participants with PVCs were included in the PVC group and a control group of participants without PVCs was set in a nested case-control study to calculate the rate of complications for lifestyle-related diseases and the risk rate of PVCs for lifestyle-related habits. RESULTS: Within the participant group, PVCs were observed in 303 individuals (1.7%). When compared with the control group, the occurrence of regularly drinking alcohol (P=0.009) and insomnia (P=0.006) were significantly higher in the PVC group. Factors related to the onset of PVCs were examined using univariate analysis. The odds ratio (OR) was 1.731 in participants who regularly drank alcohol (95% CI: 1.146-2.633, P=0.009) when compared with participants who did not regularly drink alcohol, and 1.569 in participants with insomnia (95% CI: 1.023-2.422, P=0.040) when compared with participants without insomnia. CONCLUSION: The frequency of PVCs recorded at regular medical checkups in Japanese office workers without heart disease was 1.7%. Within our group of participants, the factors related to the onset of PVCs were a history of regularly drinking alcohol and sleep disorders.

The Factors Affecting the Non-dipper Pattern in Japanese Patients with Severe Obstructive Sleep Apnea.

Objective Obstructive sleep apnea (OSA) is assumed to influence the circadian blood pressure (BP) fluctuation, particularly causing nocturnal hypertension and changing the dipping pattern of nocturnal BP. This study aimed to clarify the triggers of the non-dipper pattern in nocturnal BP in Japanese patients with severe OSA (the apnea-hypopnea index ≥30/h). Methods Of 541 patients with OSA diagnosed using polysomnography (PSG) and ambulatory BP monitoring (ABPM), 163 patients <60 years of age (Younger group) and 101 patients ≥60 years of age (Older group) were stratified into the dipper or non-dipper pattern groups. Results A logistic regression analysis was performed using a non-dipper pattern as a dependent variable. A multivariate analysis demonstrated that the cumulative percentage of time at saturation below 90% was the only independent risk factor for the non-dipper and riser patterns in the Younger group (odds ratio, 1.022; 95% confidence interval, 1.001-1.044; p=0.035), whereas slow-wave sleep (odds ratio, 0.941; 95% confidence interval, 0.891-0.990; p=0.019) and the use of angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers (odds ratio, 2.589; 95% confidence interval, 1.051-6.848; p=0.039) were risk factors in the Older group. Conclusion These findings suggested that the degree of desaturation in young OSA patients and sleep quality in old OSA patients might influence the dipping patterns in nocturnal BP.

A daytime normotensive patient with nocturnal hypoxia-induced hypertension and severe obstructive sleep apnea.

This is the case of a 60-year-old male. He had no past medical history at a regular medical check-up. According to findings at the regular medical check-up, he was obese (body mass index, 32.8 kg/m2), and had short neck, small jaw, and low soft palate; therefore, it was suspected that he may have sleep-disordered breathing. Blood pressure (BP) at the medical check-up was 121/80 mmHg, and the results of electrocardiogram and chest radiography were normal. Blood test data at the medical check-up indicated abnormality of lipid metabolism and hyperuricemia. No other abnormalities were found. It became clear that he became sleepy during daytime at an additional medical interview. Accordingly, he was diagnosed as having severe obstructive sleep apnea (OSA) with apnea-hypopnea index 65.3/h and arousal index 64.4/h by polysomnography. The oxygen-triggered nocturnal BP monitoring that was conducted at home around the same time indicated remarkable hypoxia-induced hypertension (Day 1: hypoxia-peak nocturnal BP 181/117 mmHg, Day 2: hypoxia-peak nocturnal BP 204/137 mmHg). The patient recognized the risk of OSA by visualizing the hypoxia-induced hypertension; therefore, introduction of continuous positive airway pressure (CPAP) therapy for severe OSA was smooth. As the results of CPAP therapy, we could confirm disappearance of hypoxia-induced hypertension. .

Impact of obstructive sleep apnea and hypertension on left ventricular hypertrophy in Japanese patients.

The incidence of cardiovascular disease and mortality rates are high among patients with left ventricular hypertrophy (LVH). Obstructive sleep apnea (OSA) has been reported to increase left ventricular mass (LVM) and cause LVH. The prevalence of hypertension, a major cause of increased LVM, is high in OSA; however, it is still unknown whether OSA is an independent factor that increases LVM in addition to triggering LVH. This study investigated out-of-office blood pressure (BP) via ambulatory BP monitoring (ABPM) in patients with OSA diagnosed by polysomnography (PSG) and sought to determine the effects of OSA and hypertension on LVM. A total of 432 patients with OSA underwent ABPM and echocardiography. These patients were stratified into four groups according to their left ventricular mass index (LVMI) quartiles, and the component factors influencing LVMI, such as patient background, sleep data and all-day BP data, were analyzed. This study included 356 men and 76 women. The mean age was 54.6±13.2 years, the mean body mass index was 26.7±4.6 kg m-2 and the mean apnea-hypopnea index (AHI) was 37.9±22.5. Multivariate analysis indicated that antihypertensive agent use (ß=0.143, P=0.002), an AHI ⩾15/h (ß=0.100, P=0.045) and 24-h systolic BP (ß=0.252, P<0.001) were significant independent factors for increased LVM. The significant LVMI component factors in OSA patients were an AHI ⩾15/h and 24-h systolic BP. The results of this study demonstrated that both elevated BP and OSA were independently associated with increased LVM.

Effect of oral appliance therapy on blood pressure in Japanese patients with obstructive sleep apnea.

OBJECTIVE: Obstructive sleep apnea (OSA) treatment in patients with OSA and hypertension reduces blood pressure (BP). Oral appliance (OA) therapy is nowadays prescribed for patients with mild to moderate OSA. This study aimed to clarify the effect of OA therapy on BP reduction in Japanese patients with mild to moderate OSA. METHODS: Polysomnography was employed to detect sleep-disordered breathing. Totally, 237 patients without cardiac and/or cerebrovascular diseases and those with apnea-hypopnea index (AHI) ≥ 5/h-< 30/h were enrolled. Office BP change after receiving 8-12 weeks of OA therapy was assessed and the factors related to the degree of BP reduction were analyzed. RESULTS: The study patients consisted of 188 men and 49 women, the mean age was 54.7 ± 13.2 years old, and the body mass index (BMI) was 24.6 ± 3.4 kg/m(2). The antihypertensive effect of OA therapy resulted in systolic BP (SBP) -2.4 ± 14.8 (p = 0.078) and diastolic BP (DBP) -2.0 ± 11.7 mm Hg (p = 0.045) in all patients. SBP before OA therapy played a significant role in the degree of SBP reduction (ß = -0.597, p < 0.001), whereas DBP before OA therapy was a significant factor of the degree of DBP reduction (ß = -0.522, p < 0.001). CONCLUSION: A certain time period of OA therapy effected BP reduction in mild to moderate OSA patients without cardiac and/or cerebrovascular diseases. Its antihypertensive effect was greater in OSA patients whose BP was higher before receiving OA therapy.

Influence of gender and types of sports training on QT variables in young elite athletes.

UNLABELLED: Influence of gender and sports training on QT variables such as QT interval and dispersion (QT dispersion: QTD) in young elite athletes were evaluated. Subjects included 104 male and 97 female Japanese elite athletes (mean age 21.6 years). Sports included basketball, fencing, gymnastics, judo, swimming, tennis, track and field and volleyball. Age-matched healthy non-athletes (32 men and 20 women) were enrolled as controls. QT measurements were manually obtained from a 12-lead resting electrocardiogram and QTD was calculated as the difference between the longest and shortest QT intervals. A corrected QT interval (QTc) was obtained using Bazett's formula. Subjects were divided into two groups; an endurance training group and a static training group on the basis of their training types. RESULTS: Maximum and minimum QTc were significantly longer in female athletes than in male athletes (max: 414.2 vs. 404.5 ms, min: 375.1 vs. 359.2 ms, p<0.0001 respectively), whereas QTc dispersion (QTcD) was shorter in female athletes than in male athletes (39.2 vs. 45.3 ms, p<0.0001). QTcD was significantly shorter in female athletes than in the female control group (39.2 vs. 45.2 ms, p<0.05). However, no statistically significant difference was observed between male athletes and the male control group. Male gymnasts exhibited significantly longer QTcD than the control group (p<0.01), but female gymnasts had significantly shorter QTcD than the control group (p<0.05). Maximum QTc intervals were prolonged in the male static training group compared with non-athletes, and QTcDs in the static training group were prolonged compared with the endurance training group. However, no significant difference was observed in the female group. In conclusion, both gender and different characteristics of sports training may affect QT variables even in young elite athletes. Vigorous static exercise training may independently prolong QT variables.

Effects of continuous positive airway pressure therapy in three Japanese patients with obstructive sleep apnea and resistant hypertension.

The following three case reports present the effects of 6-month continuous positive airway pressure (CPAP) therapy on blood pressure (BP) in severe obstructive sleep apnea patients with resistant hypertension. Case 1 A 58-year-old woman exhibited a decreased 24-hour BP and changes in the nocturnal BP dipping pattern from non-dipper to dipper. Case 2 A 64-year-old man showed no improvements in nocturnal BP. Case 3 A 78-year-old man with ischemic cardiomyopathy exhibited changes in the nocturnal BP dipping pattern from non-dipper to dipper. These results suggest that 6-month CPAP therapy improves the nocturnal BP dipping status in some patients with obstructive sleep apnea and resistant hypertension.