Objectives To investigate the clinical characteristics of patients with normokalemic and hypertensive primary aldosteronism.

Methods The clinical data of 224 cases with normokalemic and hypertensive primary aldosteronism from 2006 to 2010 in the hypertension department of the peoplel's hospital of Xinjiang Uygur autonomous region were analysed retrospectively. Primary aldosteronism was diagnosed by aldosterone-to-rennin activity ratio(ARR) screening and confirmation tests(including Captopril challenge test and sodium infusion test)

Results The prevalence of 1, 2 and 3 stage hypertension in all subjects were 4.47%, 18.3% and 77.23%, respectively. The main symptoms were headache (52.07%), dizzy (49.7%), fatigue (4.14%), palpitation (2.96%), limbs numbness (1.78%), respectively. The average serum sodium level was (140.75±2.75) mmol/l. The incidence of hypernatremia was only 4.91%. The proportion of the patients with normokalemic and hypertensive primary aldosteronism who had the renin activity of less than 1 ng ml⁻¹ h⁻¹ was 97.32%. To screen the patients with normokalemic and hypertensive primary aldosteronism, the diagnostic positive rate of ARR≥20 (ng/dl)/[ug/(L·h)]combined with low renin activity was significantly higher than that of the low renin activity combined with high aldosterone level, ARR ≥20 (ng/dl)/(μg/(L·h) combined with high aldosterone level and ARR≥30 (ng/dl)/(μg/(L·h) as a screening standard (χ²=18.95, p<0.001; χ²=31.13, p<0.001; χ²=29.25, p<0.001).

Conclusions The majority present moderate to severe hypertension with low rennin activity and normal serum sodium level in normokalemic and hypertensive primary aldosteronism patients. Cerebial vascular complication is relatively more common than coronary heart disease. It is helpful to decrease the missed diagnosis rate for ARR combined with low renin activity as a screening index of the patients with normokalemic and hypertensive primary aldosteronism.