Metabolic syndrome in primary aldosteronism and essential hypertension: Relationship to adiponectin gene variants

Abstract 

Background and aims

Evidence shows that aldosterone excess is crucial for the development of cardiac and metabolic complications. Among the possible pathogenetic elements of the metabolic syndrome, adiponectin and its polymorphisms seem to confer a genetic risk for metabolic alterations and type 2 diabetes.

Aims of the study were to investigate whether metabolic syndrome represents a common feature in patients with primary aldosteronism (PA) compared with essential hypertensives (EH) and to study the impact of two common adiponectin gene variants on the parameters of metabolic syndrome.

Methods and results

Metabolic syndrome was defined according to ATPIII criteria. Eighty-nine patients with PA and 164 matched EH were studied. In all patients with PA and in 135 EH two single nucleotide polymorphisms of the adiponectin gene, T45G and G276T, were detected. Patients with PA displayed a higher prevalence of metabolic syndrome compared with EH (45% vs. 30%, p<0.05). In patients with PA, genotypes 45T/G+G/G were associated with significantly lower values of waist circumference, HOMA-IR and serum aldosterone. In both PA patients and EH, the 276T/T genotype was associated with significantly worse metabolic profile and a higher risk for the metabolic syndrome (OR=1.5 for PA and OR=1.3 for EH).

Conclusions

Our data confirm a higher prevalence of metabolic syndrome among patients with PA compared with matched EH. Genetic analysis of T45G and G276T adiponectin gene polymorphisms showed that, while the genotypes 45G/G+G/T seemed to have a protective role on the metabolic complications, the genotype 276T/T defined PA and EH patients with a worse metabolic profile.

Keywords: Metabolic syndrome, Primary aldosteronism, Essential hypertension, Adiponectin gene, Polymorphisms