Association of visceral adiposity and clinical outcome among patients with aldosterone producing adenoma

Abstract

Introduction: Primary aldosteronism (PA) is a common form of secondary hypertension that has significant cardiovascular events and increased prevalence of metabolic syndrome and diabetics. Although plasma aldosterone concentration is positively correlated with visceral fat area (VFA) in non-PA individuals, the role of visceral adiposity associated with clinical success after surgery is not known.

Research design and methods: We analyzed patients who underwent adrenalectomy for aldosterone-producing adenoma (APA) at the Taiwan PA Investigator group. VFA was calculated from the abdominal CT scan at APA diagnosis, and all patients received adrenalectomy.

Results: The study involved 100 consecutive patients with APA (42 males; mean age 49.3 years) matched with 41 essential hypertension (EH) patients. Patients with APA had smaller VFA (p=0.010) than their EH counterparts. Multiple linear regression analysis revealed that the duration of hypertension (p=0.007), but not plasma aldosterone, was negatively correlated with VFA in patients with APA. Logistic regression analysis showed that log VFA (OR=0.065, p<0.001) and duration of hypertension before PA diagnosis (OR=0.919, p=0.011) can predict complete clinical success after adrenalectomy. Multifactor-adjusted generalized additive model demonstrated that log VFA <9.2 was associated with complete cure of hypertension. Furthermore, VFA was increased at 6 months after adrenalectomy (p=0.045).

Conclusions: Patients with APA had smaller VFA than their EH counterparts, and VFA increased after adrenalectomy. Clinical complete cure of hypertension after surgery was associated with smaller VFA and shorter duration of hypertension at PA diagnosis, suggesting a potential interplay of visceral adiposity and aldosterone of the patients with APA.

Keywords: adipocyte; adipocyte secretion; adipocytes - metabolism; adipose tissue.

Figure 1

APA patients with log VFA smaller than 9.2 had a clinical advantage in clinical complete success. GAM plot for the probability of cure of hypertension against log VFA level of APA patients at index date incorporating the subject-specific random effects expressed as the logarithm of the odds (logit). The probability of outcome events was constructed with hypertensive duration have an average of zero over the range of the data, that is, log VFA=9.2. The dashed lines indicate approximated point-wise 95% CI. Data are expressed as mean±SD unless otherwise indicated. APA, aldosterone-producing adenoma; GAM, generalized additive model; HTN, hypertension; VFA, visceral fat area.

Figure 2

Log postoperation VFA (after adrenalectomy) and log preoperation VFA (before adrenalectomy) of 20 patients with APA. APA, aldosterone-producing adenoma; VFA, visceral fat area.