Role of renin–angiotensin aldosterone system on short-term blood pressure variability in hypertensive patients

Comparison of ambulatory blood pressure between patients with primary aldosteronism and other forms of hypertension

OBJECTIVE

Primary aldosteronism (PA) is a potentially curable cause of hypertension associated with worse cardiovascular prognosis than blood pressure-matched essential hypertension (EH). Effective targeted treatment for PA is available with the greatest benefit seen if treatment is started early, prior to the development of end-organ damage. However, PA is currently substantially under-diagnosed. The standard screening test for PA, the aldosterone-to-renin ratio (ARR), is performed infrequently in both primary and tertiary care. In contrast, ambulatory blood pressure monitoring (ABPM) is frequently utilized in the assessment of hypertension. The aim of this study was to compare ABPM parameters in hypertensive patients with and without PA, in order to identify features of ABPM associated with PA that can prompt screening.

STUDY DESIGN

Patients with PA (n = 55) were identified from a tertiary clinic specializing in the management of endocrine causes of hypertension whilst the controls (n = 389) were consecutive patients with hypertension but without a known diagnosis of PA who were referred for ABPM.

RESULTS

In this study, PA patients were younger and had higher 24-h, day, and night-time blood pressure compared with controls despite similar number of antihypertensive medications. However, there was no significant difference in nocturnal dipping or day-night blood pressure variability between the two groups.

CONCLUSIONS

An elevated ambulatory blood pressure in patients on multiple antihypertensives could suggest underlying PA but in the absence of other distinguishing features, ABPM could not reliably differentiate PA from other forms of hypertension. Routine biochemical screening for PA remained the most reliable way of detecting this treatable secondary cause of hypertension.

NR3C2 gene polymorphism is associated with risk of gestational hypertension in Han Chinese women

BACKGROUND

The influence of genetic polymorphisms on the development of gestational hypertension (GH) is unclear. The aim of this study was to examine whether single-nucleotide polymorphisms (SNPs) of the nuclear receptor subfamily 3, group C, member 2 (NR3C2) genes, rs5522, rs2070951, rs5534, s2248038, and s9992256 are associated with GH in Han Chinese women.

METHOD

Sanger sequencing was used to analyze the genotypes of rs5522, rs2070951, rs5534, rs2248038, and rs9992256 loci of the NR3C2 gene in 450 patients with GH and 450 healthy controls.

RESULTS

The rs5522 dominant model (odds ratio [OR] = 1.30, 95% confidence interval [CI]: 1.13-1.47, P < .001) and the recessive model (OR = 1.64, 95% CI: 1.33-1.86, P < .001) had higher GH risk. The rs2070951 dominant model (OR = 1.18, 95% CI: 1.03-1.35, P = .02) had higher risk of GH, and the recessive model (OR = 1.09, 95% CI: 0.84-1.34, P = .55) was not significant for GH risk. The rs5534 dominant model (OR = 1.25, 95% CI: 1.09-1.43, P = .001) had a higher GH risk. The rs2248038 and rs9992256 sites were not significantly related to GH risk. Gene-gene interactions at the rs5522, rs2070951, and rs5534 loci affected GH risk (OR = 1.34, 95% CI: 1.12-1.64, P < .001).

CONCLUSION

The SNPs of the NR3C2 gene rs5522, rs2070951, and rs5534 are associated with GH in Han Chinese women.

Involvement of the renin-angiotensin system in the progression of severe hand-foot-and-mouth disease

BACKGROUND

Hand-foot-and-mouth disease (HFMD) is generally considered as a mild exanthematous disease to infants and young children worldwide. HFMD cases are usually mild and self-limiting but for few cases leads to complicated severe clinical outcomes, and even death. Previous studies have indicated that serum Ang II levels in patients with H7N9 infection were related to the severity of infection. However, the mechanisms underlying the pathogenesis of severe HFMD remain unclear. This study was undertaken to clarify the role of the renin-angiotensin system (RAS) in the progression of severe HFMD.

METHODS

In the present study, 162 children including HFMD patients and healthy controls were recruited. The data was analyzed by time-series fashion. Concentrations of angiotensin II (Ang II) and noradrenaline (NA) in serum of patients were measured with ELISA. We established a mouse model for enterovirus 71 (EV71) infection and determined concentrations of Ang II, NA in tissue lysates at 3, 5 and 7 days post infection (dpi).

RESULTS

The concentrations of Ang II and NA in serum of the HFMD patients with mild or severe symptoms were significantly higher than that in healthy controls. Additionally, the concentrations of Ang II and NA in serum of severe cases were significantly higher than those mild cases and the increased concentrations of Ang II and NA showed the same time trend during the progression of HFMD in the severe cases. Furthermore, the concentrations of Ang II and NA in target organs of EV71-infected mice including brains, skeletal muscle, and lungs were increased with the progression of EV71 infection in mice. Histopathological alterations were observed in the brains, skeletal muscle and lungs of EV71-infected mice.

CONCLUSION

Our study suggested that activation of the RAS is implicated in the pathogenesis of severe HFMD.