No impact of hyperkalaemia with renin-angiotensin system blockades in maintenance haemodialysis patients.
BACKGROUND
Renin-angiotensin system (RAS) blockades, angiotensin converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) are well accepted for the cardiorenal-protective benefits added to antihypertensive effects in chronic kidney diseases (CKD), but associated with an increased risk of hyperkalaemia. However, few studies have investigated the effect of RAS blockades on serum potassium in dialysis patients.


METHODS
Hyperkalaemia associated with RAS blockades by ACEI and/or ARB was evaluated in 69 patients on maintenance haemodialysis, who underwent a three-period crossover study in four groups (no exposure to RAS blockades, ACEI or ARB alone and ACEI plus ARB treatments), lasting one month in each period.


RESULTS
Sixty-two patients completed this prospective 3-month study, and no one stopped the study because of the development of hyperkalaemia and/or complications. Mean serum K was similar among the four periods (no exposure, 5.54+/-0.67 mmol/l; ACEI alone, 5.54+/-0.75 mmol/l; ARB alone, 5.50+/-0.66 mmol/l; ACEI+ARB combination, 5.42+/-0.66 mmol/l) and was also equal when compared between the two groups with and without exposure to RAS blockades (5.48+/-0.68 vs 5.54+/-0.67 mmol/l, P=NS). The incidence of severe hyperkalaemic episodes (>6.0 mmol/l) upon monthly predialysis serum K determination was 25.8% with no exposure to RAS blockades, 29.8% for ACEI alone, 19.6% for ARB alone and 17.7% for ACEI+ARB combination without statistically significant differences among the four periods (P=NS). Among covariables, the degree of Kt/V, intakes of other medications interfering with potassium homeostasis and diabetes mellitus did not result in any significant hyperkalaemic changes during the 3-month study period except anuric patients compared with non-anuric patients (5.58+/-0.69 vs 5.19+/-0.65 mmol/l, P<0.001).


CONCLUSIONS
Neither monotherapy (ACEI or ARB) nor combination therapy (ACEI plus ARB) is associated with the additional risk of hyperkalaemia in patients on maintenance haemodialysis. However, those patients with anuria on RAS blockades warrant the cautious monitoring of serum K to prevent hyperkalaemia.
Han
Sang-Woong
SW
Division of Nephrology, Department of Internal Medicine, Hanyang University Guri Hospital, 249-1, Gyomoon-dong, Guri, Gyeonggi, 471-701, Republic of Korea.
Won
Young-Woong
YW
Yi
Joo-Hark
JH
Kim
Ho-Jung
HJ
D000328:Adult; D000368:Aged; D047228:Angiotensin II Type 1 Receptor Blockers / Q000009:adverse effects* / Q000627:therapeutic use; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D002318:Cardiovascular Diseases / Q000517:prevention & control; D018592:Cross-Over Studies; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D006947:Hyperkalemia / Q000097:blood / Q000139:chemically induced*; D015994:Incidence; D007676:Kidney Failure, Chronic / Q000628:therapy*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000097:blood; D011446:Prospective Studies; D006435:Renal Dialysis / Q000379:methods*; D012084:Renin-Angiotensin System / Q000187:drug effects*; D012307:Risk Factors; D012720:Severity of Illness Index
D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors; D011188:Potassium