Correction: Continuous Positive Airway Pressure Treatment Reduces Mortality in Elderly Patients with Moderate to Severe Obstructive Severe Sleep Apnea: A Cohort Study.

[This corrects the article DOI: 10.1371/journal.pone.0127775.].

Increased plasma lactate level is associated with subclinical cardiovascular damage in patient with non-dipping hypertension.

OBJECTIVE: To evaluate the difference of plasma lactate level between dipping and non-dipping hypertension, and to investigate the effects of lactate on subclinical cardiovascular damages in dipping and non-dipping hypertension. METHODS: According to 24 h ambulatory blood pressure monitoring, 236 patients with dipping and 152 with non-dipping hypertension were included. Clinical characteristics were collected and compared between dipping and non-dipping groups. Left ventricle hypertrophy (LVH) and N-terminal pro-B type natriuretic peptide (NT-proBNP) level were used to evaluate subclinical cardiovascular damage. Multivariate regression analysis was performed to evaluate the relationship between lactate and LVH and NT-proBNP elevation. RESULTS: Compared to dipping hypertension, plasma levels of lactate and NT-proBNP in non-dipping hypertension group were significantly higher. Moreover, the value of left ventricle mass index to height (LVMI/height) was also significantly higher in non-dipping group, and the percentage of patient with LVH was also higher in non-dipping group (36.8% vs. 28.9%, P < 0.05). Multivariate regression analysis revealed that in non-dipping group, after fully adjustment, the associations between lactate with LVH and NT-proBNP remained significant, with odds ratio (OR) of 1.18 (95% confidence interval [CI] of 1.13-1.24) in LVH and OR of 1.16 in NT-proBNP (95% CI of 1.10-1.23), respectively. Nonetheless, the associations between lactate with LVH and NT-proBNP elevation in dipping group were diminished to statistical nonsignificance. CONCLUSION: Plasma lactate level in non-dipping hypertension is significantly higher than dipping hypertension, and this difference may be the potential mechanism non-dipping hypertension contributes to greater targeted organ damage.

Continuous Positive Airway Pressure Treatment Reduces Mortality in Elderly Patients with Moderate to Severe Obstructive Severe Sleep Apnea: A Cohort Study.

Obstructive sleep apnea (OSA) is much more prevalent in older people than in middle-aged or young populations, and has been associated with cardiovascular disease. Continuous positive airway pressure (CPAP) is the first-line therapy for OSA, but its long-term clinical benefit in the elderly is unclear. Here, we carried out a prospective cohort study to explore the survival rate and incidence of cardiovascular events in elderly patients with moderate to severe OSA who did or did not receive CPAP treatment. The study included 130 patients (104 male, 26 female; mean age: 77.8 ± 6.2 years) who were followed up for a mean of 5 ± 2.54 years (range, 1-8 years). Thirty-six patients received CPAP and 88 had no CPAP. The results showed that mortality in the untreated group (21.6%) was significantly higher than in the CPAP group (5.6%). Kaplan-Meier survival analysis showed that the survival rate in the CPAP group was 94.4%, which was markedly higher than the rate of 78.4% in the untreated group. The incidence of cardiovascular events was 13.9% in the CPAP group and 55.7% in the untreated group. The present study provides evidence that CPAP can reduce mortality in older patients with moderate to severe OSA, and lead to a good long-term prognosis. The study also indicates that death in older OSA patients is associated with cardiovascular disease and diabetes.

[Effect of obstructive sleep apnea syndrome on blood lipid and blood glucose in elderly hypertensive patients].

OBJECTIVE: To investigate the effect of obstructive sleep apnea syndrome (OSAS) on blood lipid and blood glucose in elderly hypertensive patients. METHOD: a One hundred and seven elderly hypertensive patients received examinations by polysomnography and according to the apnea-hypopnea index (AHI), the patients were divided into four groups, namely uncomplicated hypertension group (n=23) and 3 hypertension groups with mild (n=31), moderate (n=29) and severe (n=24) OSAS. The fasting and 2-hour postprandial plasma glucose, glycosylated hemoglobin (HbA1c), total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), Apo-A, and Apo-B of these patients were measured. RESULTS: aCompared with the non-OSAS patients, all the OSAS patients showed increased fasting and 2-hour postprandial plasma glucose, HbA1c, TC, TG, LDL and TC/HDL, and the increments were statistically significant in severe OSAS patients (P<0.05). The level of HDL was lowered in the OSAS groups, showing significant difference between severe OSAS group and the non-OSAS group (P<0.05). Apo-A level was lowered and Apo-B increased in the OSAS groups, but the differences were not statistically significant (P>0.05). CONCLUSIONS: OSAS may produce harmful affect on the blood glucose and blood lipids in elderly hypertensive patients.

[Clinical analysis of coronary artery disease in elderly patients with sleep disordered breathing].

OBJECTIVE: To understand the prevalence of sleep disordered breathing (SDB) in elderly patients with coronary artery disease (CAD) and explore the relations between SDB and CAD. METHODS: Sixty-two elderly patients with and 18 without CAD identified by coronary angiography underwent examinations by polysomnography (PSG). Left ventricular ejection fraction (LVEF) was measured by 99Tc equilibrium radionuclide angiography. RESULTS: In the 62 elderly patients with CAD, 53.2% had SDB, a rate significantly higher that (22.2%) in the 18 non-CAD patients. The CAD patients with SDB had higher respiratory disturbance index (RDI) and body mass index (BMI) and lower arterial saturation of oxygen (SaO2) during sleep, with longer duration of low SPO2 (less that 90%). The incidence of hypertension was higher in CAD patients with SDB than in those without SDB. No significant correlation was found between the severity of coronary artery disease and RDI (r=-0.16, P>0.05). CONCLUSION: The elderly patients with CAD have higher incidence of SDB, and appropriate interventions should be administered in those with severe SDB.

[Relationship between chronic congestive heart failure and sleep-disordered breathing in elderly patients].

OBJECTIVE: To determine the prevalence of sleep disordered breathing (SDB) in elderly patients with chronic congestive heart failure (CHF) and explore the relations between SDB and left ventricular function. METHODS: By means of polysomnography, 56 elderly patients with CHF were divided into non-SDB, mild SDB, moderate SDB, and severe SDB groups, and the left ventricular ejection fraction (LVEF) was measure by (99)Tc equilibrium radionuclide angiography. RESULTS: In the 56 elderly patients with CHF, 38 (67.9%) had SDB, including 12 (21.4%) mild SDB, 14 (25.0%) moderate SDB, and 12 (21.4%) severe SDB patients. Thirty (53.6%) of the 56 patients with CHF had obstructive sleep apnea (OSA), 4 (7.1%) had central sleep apnea and 22 (39.2%) had mixed sleep apnea. The moderate and severe SDB groups had lower minimum arterial oxyhemoglobin saturation during sleep than the non-SDB groups, and the apnea-hyponea index was closely related to LVEF (r=-0.74, P<0.01). CONCLUSION: The prevalence of SDB, predominantly OSA, is high in elderly patients with CHF. Moderate and severe SDB might affect the left ventricular function in these patients, who require polysomnography monitoring.