Poster Presentation The Joint Annual Scientific Meetings of the Endocrine Society of Australia and the Society for Reproductive Biology 2017

24-hour blood pressure profile may distinguish primary aldosteronism from essential hypertension (#202)

Serena Menezes 1 , Om Narayan 2 , Stella Gwini 3 , Jimmy Shen 4 5 , Jun Yang 4 5 , Morag Young 5
  1. Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Victoria, Australia
  2. Monash Heart, Monash Health, Clayton, Victoria, Australia
  3. Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Clayton, Victoria, Australia
  4. Department of Endocrinology, Monash Health, Clayton, Victoria, Australia
  5. Centre for Endocrinology and Metabolism, Hudson Institute of Medical Research, Clayton, Victoria, Australia

BACKGROUND

Primary aldosteronism (PA) has a reported prevalence of up to 20% in cases of resistant hypertension1. Untreated PA poses a significantly greater risk of cardiovascular events than essential hypertension (EH)2. Ambulatory blood pressure (AMBP) monitoring provides a non-invasive method for evaluating circadian BP variations, offers valuable prognostic information3 and may distinguish PA from EH.

 

OBJECTIVE

To compare AMBP parameters in patients with PA and EH, and correlate these parameters with cardiovascular outcomes in PA.

 

METHODS

AMBP readings were evaluated retrospectively in 407 patients assessed at Monash Heart. Patient demographics, screening aldosterone and renin concentrations and medications were retrieved from medical records. 396 EH and 11 PA patients were identified and their cardiovascular events (myocardial infarction, left ventricular hypertrophy, coronary artery disease, atrial fibrillation) were recorded. Statistical significance was set at p<0.05.

 

RESULTS

Compared to EH, PA patients were younger (mean: 51.5±13.3 vs 62.2±14.2 years). Mean BP readings were higher in PA (mean: 150/86±20.5/7.4 vs 134/75±17.2/10.7 mmHg) and similar findings were observed for average daytime and nighttime BP readings. BP load (% daytime and nighttime SBP/DBP readings over 135/85 and 120/70 mmHg, respectively) was significantly higher for both systolic and diastolic in PA (mean: 72.4±26.4 and 50.2±25.6 %) compared with EH (mean: 49.3±28.5 and 21.6±22.7 %). 81% of patients with PA (9/11) had loss of physiological nocturnal BP dipping compared with 44% of EH (175/396). Rates of cardiovascular events were similar in both groups but may be confounded by the retrospective nature of this study and lack of long-term follow-up.

 

CONCLUSION

In our study, PA is associated with a significant increase in BP load and loss of nocturnal BP dipping which are known risk factors for adverse cardiovascular events. A prospective study is needed to better define AMBP parameters in PA and evaluate changes following treatment.

  1. 1. Funder, J et al. The Management of Primary Aldosteronism: Case Detection, Diagnosis, and Treatment: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab 2016; 101 (5): 1889-1916.
  2. 2. Milliez, P et al. Evidence for an increased rate of cardiovascular events in patients with primary aldosteronism. J Am Coll Cardiol 2005; 45:1243–1248.
  3. 3. Boggia, J et al. Prognostic accuracy of day versus night ambulatory blood pressure: a cohort study. The Lancet 2007; 370 (9594): 1219-1229.