Association between severe obstructive sleep apnea and incident arterial hypertension in the older people population.

OBJECTIVES: The impact of sleep-related breathing disorders on the incidence of arterial hypertension (AHT) in the older adults is not well-established. The aim of our study was to test the link between severe obstructive sleep apnea (OSA) and the occurrence of hypertension in older subjects after 3 years. METHODS: 372 normotensive subjects with a mean age of 68.2 years were included in our longitudinal study. All participants had a ventilatory polygraphic recording and an ambulatory blood pressure (BP) monitoring at baseline and after 3 years. Severe OSA was defined by an apnea-hypopnea index (AHI) of ≥ P30 per hour. A new onset of hypertension was defined according to a mean 24-hour value >140mmHg for systolic BP and >85mmHg for diastolic BP or the use of antihypertensive medication. RESULTS: The baseline factors significantly associated with an increased risk for new-onset hypertension were male gender, obesity, diabetes mellitus (DM), dyslipidemia, and OSA. Multiple logistic regression analyses showed that an AHI ≥30 per hour was independently associated with incident hypertension after 3 years (P=.02; odds ratio [OR], 1.8; 95% confidence interval [CI], 1.1-2.8). CONCLUSIONS: The presence of severe OSA is associated with new-onset AHT in normotensive elderly (mean age, 68.2 y) subjects.

At 68 years, unrecognised sleep apnoea is associated with elevated ambulatory blood pressure.

After the age of 65 yrs the specific impact of unrecognised sleep-related breathing disorders (SRBD) on 24-h blood pressure (BP) levels remains under debate. We tested the cross-sectional relationship between the severity of obstructive sleep apnoea/hypopnoea (OSAH) and the increase of BP using ambulatory BP monitoring (ABPM) in the PROOF (PROgnostic indicator OF cardiovascular and cerebrovascular events study)-SYNAPSE (Autonomic Nervous System Activity, Aging and Sleep Apnea/Hypopnea study) cohort. 470 subjects (aged 68 yrs) neither treated for hypertension nor diagnosed for SRBD were included. All subjects underwent ABPM, and unattended at-home polygraphic studies. OSAH was defined by an apnoea/hypopnoea index (AHI) >15 · h(-1). The severity of the sleep apnoea was also quantified as the index of dips in oxyhaemoglobin saturation >3% (ODI). Results are expressed in per protocol analysis. Severe OSAH (AHI >30 · h(-1), 17% of subjects) was associated with a significant 5 mmHg increase in both diurnal and nocturnal systolic BP (SBP), and with a nocturnal 3 mmHg increase in diastolic BP (DBP). Systolic (mean SBP >135 mmHg) or diastolic (mean DBP >80 mmHg) hypertension were more frequently encountered in subjects suffering from moderate (AHI 15-30) or severe OSAH. After adjustment, the independent association between severe OSAH and 24-h systolic hypertension remained significant (OR 2.42, 95% CI 1.1-5.4). The relationship was further reinforced when SRBD severity was expressed using ODI >10 · h(-1). The impact of unrecognised SRBD on BP levels also exists at the age of 68 yrs. The hypoxaemic load appears to be the pathophysiological cornerstone for such a relationship.

Autonomic activation during sleep and new-onset ambulatory hypertension in the elderly.

BACKGROUND: Sympathetic "overactivity" during night is a well recognized factor of hypertension development in adults. However, the deleterious effect of nocturnal autonomic activation in elderly remains controversial. METHODS: Subjects, all aged 65 years at baseline, were selected from the PROOF cohort study, a prospective observational cohort of subjects. Exclusion criteria were previous myocardial infarction, stroke, heart failure, type-1 diabetes, atrial fibrillation or anti-arrhythmic drug. Normotensive subjects were selected according to: 24-h ambulatory blood pressure (BP) measurements <135/85 mm Hg, absence of self-report antihypertensive treatment. Autonomic activation during sleep was evaluated from night-time ECG Holter recording. According the %VLFI (Very-Low Frequency component of Interbeat Interval Increment evaluated from heart rate variability analysis). Subjects with new-onset ambulatory hypertension were identified after two years when daytime ambulatory blood pressure was higher than 135/85 mm Hg or when they used an antihypertensive treatment. RESULTS: Among 428 normotensive subjects at inclusion, 62 (14.5%) were considered as hypertensives after two years. Univariate logistic regression model showed a significant association between abnormal %VLFI (>4%) and new-onset hypertension: OR = 1.78 (1.03-3.07). Male gender, increased body mass index and ambulatory systolic BP were also associated with increased risk of hypertension. After adjustment in the stepwise logistic regression, abnormal %VLFI was associated with an 82% increase in odds of new-onset hypertension, independently of systolic ABPM and body mass index. CONCLUSION: Repeated autonomic activation during sleep, whatever the origin of the phenomenon, may trigger hypertension development in the elderly.