Add-on aliskiren treatment can decrease blood pressure but requires attention to risks of renal impairment and hyperkalemia Chikushi Anti-Hypertension Trial-Rasilez® (CHAT-Ras)

ABSTRACT

Background

Renin is the starting point of the renin angiotensin (RA) system cycle. Aliskiren (AL), which is a direct renin inhibitor, suppressed the entire RA cycle. In the present study, the efficacy of add-on of AL treatment in patients with essential hypertension (HT) was investigated.

Methods

This study was a multi-center, open-label, prospective, observational study. Study subjects were patients with essential HT and poor blood pressure (BP) control, who had received calcium channel blocker monotherapy or angiotensin II receptor blocker monotherapy or had not received any BP lowering drugs. Following add-on of AL for 12 months, BP and additional laboratory findings were analyzed.

Results

A total of 150 subjects were enrolled. There were 50 dropout subjects including discontinuation. Dropouts were the highest in the ARB combination therapy group at 9 subjects due to adverse events, and 3 of them were due to hyperkalemia. A significantly higher number of patients with chronic kidney disease (CKD) dropped out compared to patients without CKD (φ = 0.166, p < .05). BP before add-on of AL was 155/88 mmHg. After add-on of AL, BP was significantly improved and this lowering was sustained for 3 months (136/78 mmHg, p < .001), 6 months (136/77 mmHg, p < .001) and 12 months (134/78 mmHg, p < .001). In contrast, add-on of AL increased the potassium level and decreased the estimated glomerular filtration rate.

Conclusion

While add-on AL treatment achieved a favorable and sustained decrease of BP in this study, caution is necessary with regard to elevation of potassium levels and renal impairment.

KEYWORDS:

• Aliskiren
• renin angiotensin system
• direct renin inhibitor
• hypertension
• practitioner
• multi-center prospective study

Acknowledgments

We thank Mrs. Nao Totake for her excellent technical assistance and the general practitioners participating in Chikushi-JRN for enrollment of their patients.

Conflicts of Interests

The authors have financial conflicts of interest (Novartis Pharma K.K.) to disclose concerning this study.

Study Limitations

There may have been considerable big-day bias at the enrollment of patients (10). Moreover, with regard to study participation, the Hawthorne effect may have also played a role. Ambulatory BP and home BP were not measured. The target sample size was not achieved, and the dropout rate was high. Basically, the content of antihypertensive drugs should not have changed after the addition of AL. But the exact details are unknown.

Additional information

Funding

This work was supported by the Novartis Pharma [110477FK].