Abstract
Hypokalemia plays an important role in the diagnosis and management of primary
aldosteronism (PA). While the hypokalemic variant of the disease accounts for
about one third of all cases, little is known about the incidence of PA in
hypokalemic populations. The IPAHK+ study is an epidemiological,
cross-sectional trial to provide evidence on the incidence of PA in hypokalemic
patients from a university hospital outpatient population. Recruitment of
outpatients with hypokalemia≤3 mmol/l is carried out on
a continuous referral-basis through an automated data delivery system. Up to an
interim data closure, 66 patients underwent the study protocol. The mean age of
the participants was 52.9±1.5 years with an equal sex ratio of 1:1 women
to men, a mean potassium value of 2.78±0.31 mmol/l
[1.8;3.0] and a prevalence of arterial hypertension of 72.7%. PA was
diagnosed in 46.6% of all participants, all of whom had a history of
hypertension. Incidence of PA increased continuously with decreasing potassium
levels with proportions of 26.7%, 50% and 57.1% in the
subgroups of 3.0 mmol/l (n=15),
2.8–2.9 mmol/l (n=22)
and≤2.7 mmol/l (n=21), respectively. Prior to
testing, 59.1% of all patients presented at least with one plausible
other cause of hypokalemia. The incidence of PA in the investigated outpatient
population was more than 4 out of 10 and inversely correlated with baseline
potassium levels. Moderate or severe hypokalemia, regardless of its cause,
should therefore prompt evaluation for PA in hypertensive individuals.
Normotensive hypokalemic PA was not observed in this cohort.
Key words primary aldosteronism - hypokalemia - potassium
