Prevalence of Clinical and Ambulatory Hypertension in a Population of 65-Year-Olds: The PROOF Study

Long-term evolution of ambulatory blood pressure and cardiovascular events in hypertensive patients

Ambulatory blood pressure monitoring (ABPM) is now considered the gold standard to evaluate BP, and predicts related cardiovascular risk. However, no study has reported the association of long-term changes in ABPM with the incidence of cardiovascular events, therefore the objective of this work. We included patients from the Bordeaux cohort of hypertensive patients, who had undergone at least two ABPM; the first was performed before or after antihypertensive treatment was started, and the second was the last recording available before any cardiovascular event. We included 591 patients (mean age, 54 years) with a 7-year average interval between the first and last ABPM, a 10-year average follow-up, and a total of 111 cardiovascular events. The patients were divided into four groups: G0, first and last 24 h systolic blood pressure (SBP) < 130; G1, first 24 h SBP ≥ 130, last 24 h SBP < 130; G2, first 24 h SBP < 130, last 24 h SBP ≥ 130; and G3, first 24 h SBP ≥ 130, last 24 h SBP ≥ 130 mmHg. Baseline ABPM better predicted future events than the last ABPM. G0 and G2 had similar survival. G1 and G3 had a worse prognosis than G0 and G2, while G1 had an intermediate risk between G0 and G3, indicating some benefit of treatment. In conclusion, our study showed the prognostic value of the first ABPM recorded in hypertensive patients and the persistence of risk when 24 h BP is controlled by antihypertensive treatment.

Prevalence, Treatment, and Control Rates of Conventional and Ambulatory Hypertension Across 10 Populations in 3 Continents

Hypertension is a major global health problem, but prevalence rates vary widely among regions. To determine prevalence, treatment, and control rates of hypertension, we measured conventional blood pressure (BP) and 24-hour ambulatory BP in 6546 subjects, aged 40 to 79 years, recruited from 10 community-dwelling cohorts on 3 continents. We determined how between-cohort differences in risk factors and socioeconomic factors influence hypertension rates. The overall prevalence was 49.3% (range between cohorts, 40.0%-86.8%) for conventional hypertension (conventional BP ≥140/90 mm Hg) and 48.7% (35.2%-66.5%) for ambulatory hypertension (ambulatory BP ≥130/80 mm Hg). Treatment and control rates for conventional hypertension were 48.0% (33.5%-74.1%) and 38.6% (10.1%-55.3%) respectively. The corresponding rates for ambulatory hypertension were 48.6% (30.5%-71.9%) and 45.6% (18.6%-64.2%). Among 1677 untreated subjects with conventional hypertension, 35.7% had white coat hypertension (23.5%-56.2%). Masked hypertension (conventional BP <140/90 mm Hg and ambulatory BP ≥130/80 mm Hg) occurred in 16.9% (8.8%-30.5%) of 3320 untreated subjects who were normotensive on conventional measurement. Exclusion of participants with diabetes mellitus, obesity, hypercholesterolemia, or history of cardiovascular complications resulted in a <9% reduction in the conventional and 24-hour ambulatory hypertension rates. Higher social and economic development, measured by the Human Development Index, was associated with lower rates of conventional and ambulatory hypertension. In conclusion, high rates of hypertension in all cohorts examined demonstrate the need for improvements in prevention, treatment, and control. Strategies for the management of hypertension should continue to not only focus on preventable and modifiable risk factors but also consider societal issues.

Impaired baroreflex sensitivity and the risks of new-onset ambulatory hypertension, in an elderly population-based study

BACKGROUND

Impairment of the autonomic nervous system activity may be involved in the development of hypertension. Yet the prognostic values of heart rate variability and baroreflex sensitivity in the risk of new-onset ambulatory hypertension have not been investigated. We sought to assess the relationship between heart rate variability and baroreflex sensitivity parameters and ambulatory hypertension in a community-dwelling elderly cohort.

METHODS

Normotensive subjects were selected from the PROOF study cohort, including 1011 subjects aged 65 years at baseline. The autonomic nervous system activity was assessed through 24-hour heart rate variability and 15-minute spontaneous baroreflex sensitivity at baseline. Incident hypertension was defined with the 24-hour, day-time and night-time ambulatory blood pressure measurements and antihypertensive treatment use, at two-years of follow-up.

RESULTS

At baseline, 13.7% of subjects developed day-time hypertension, 18.2% developed night-time hypertension and 13.6% developed 24-hour hypertension. Reduced baroreflex sensitivity at baseline was associated with onset of hypertension after adjustment for blood pressure level, C-reactive protein levels and depression score (OR = 0.45 [0.23-0.86]). Indices of heart rate variability were not associated with hypertension onset.

CONCLUSION

Baroreflex sensitivity may represent an intermediate goal for prevention of ambulatory hypertension at early stage.

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.

Association of hypertension and bone mineral density in an elderly African American female population

BACKGROUND

Recent studies have shown that hypertension is inversely correlated with bone mineral density (BMD) as determined by dual energy x-ray absorptiometery (DXA) in different ethnic groups. But in most published studies, either the sample size was small or the study was limited by different measurement methods. These limitations leave this association controversial and inconclusive. The current study utilizes a sample of African American females referred for clinical screening of osteoporosis in our center to find out if any association of high blood pressure and BMD in this ethnic group exists. The secondary endpoint was to determine the effect of thiazide diuretics on BMD of the elderly African American females because, theoretically, thiazides are considered to have a positive impact on BMD.

METHODS

In this retrospective, cross-sectional study, 10 years of data were reviewed from 1113 medical records of African American females aged 65 years and older whose BMD values were measured by DXA at the lumbar spine (L1-L4) and both femoral necks (the standard sites for BMD determination) along with their T scores and Z scores (used to determine osteopenia vs osteoporosis). Our exclusion criteria included patients who: (1) were current smokers, (2) had a previous oophorectomy, (3) had a history of corticosteroid use, (4) had a history of biphosphonate use, (5) were on hormone replacement therapy, and (6) were diabetic and taking either pioglitazones or roziglitazones. A total of 148 patients were excluded from the analysis due to either incomplete data or exclusion criteria. The remaining sample was then divided into 2 groups based on their hypertensive status. For the subanalysis, the hypertensive group was further divided into 2 additional groups based on their thiazide usage.

RESULTS

We had complete data on 965 participants, of which 631 (65.3%) had a history of hypertension and 334 (34.7%) did not. Out of 631 hypertensive patients, 173 were found to be using thiazide diuretics as antihypertensive medication, while 458 were without thiazide diurectic use. The proportion of patients with both osteopenia and osteoporosis was similar in those with and without hypertension (50% vs 50%, p = .95 for osteopenia; 18% vs 19%, p = .95 for osteoporosis). There was no significant difference between the BMD at the lumbar spine, and right and left femoral necks between patients with and without hypertension. This lack of association held true when comparing the mean T scores and Z scores at the above sites. Within patients with a history of hypertension, there were no significant differences in the BMD, T score or Z score at any site with and without a history of thiazide diuretic use.

CONCLUSION

Hypertension in elderly African American females aged at least 65 years was not found to be correlated with low BMD at either the lumbar spine (L1-L4) or both femoral necks when confounding factors were taken into consideration. Mean BMD of the hypertensive cohort taking thiazide diuretics was found lower at the lumbar spine as compared to the hypertensive patients not taking thiazide diuretics.

Ambulatory blood pressure monitoring in the elderly

The incidence of hypertension is high in the elderly and is present in 2/3 of the patients older than 65 years. Prevalence can reach 90% in patients older than 80 years. The presence of isolated systolic hypertension (ISH) is characteristic of this population. However, the prevalence of hypertension by ambulatory blood pressure monitoring (ABPM) is not well known. In this study, we analyzed the special characteristics of hypertension in this population, giving special emphasis on ABPM readings.

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.