Background: Prolactin (PRL) has increasingly been recognized to play a stimulatory role in
inflammatory response. Recently, studies have reported an increase in the PRL level among
patients with chronic heart failure (HF); however, there are conflicting data about its role as
a prognostic factor in these patients. We aimed to measure the PRL level in the acute phase
of HF and the post guideline-directed medical therapy (GDMT) of HF to clarify whether
PRL is an acute-phase reactant or more than an acute phase-reactant in patients with HF.
Methods: The serum PRL level was assessed in 94 patients with HF in the acute phase of HF
decompensation and post-GDMT of HF. Serum N-terminal pro-brain natriuretic peptide,
high-sensitive C-reactive protein, 6-minute walk test, erythrocyte sedimentation rate, CRP,
blood urea nitrogen, creatinine, serum sodium, and white blood cell count were also
measured. Our secondary end points were mortality, transplantation, and hospitalization due
to acute HF. All the patients were followed up for 6 months.
Results: The mean serum PRL level in the acute phase was 31.3 ng/mL, which was significantly
higher than the normal reference values (4.04–15 ng/mL) (P < 0.001). The mean serum PRL
level before discharge was 34.84 ng/mL, which was significantly higher than the normal
reference values and similar to the acute phase values. The mean PRL level in the patients
with dilated cardiomyopathy was 33.61 ng/mL in the acute phase and 43.15 ng/mL after the
GDMT of HF. The mean PRL level in the patients without dilated cardiomyopathy was
33.42 ng/mL in the acute phase and 29.92 ng/mL before discharge. The mean PRL level in
the patients with re-admission was higher (27.7 ng/mL in the acute phase and 29.7 ng/mL
before discharge in the patients with no re-admission and 37.4 ng/mL in the acute phase and
42.5 ng/mL before discharge in the patients with re-admission).
Conclusions: In 57% of the patients, the mean level of PRL increased after treatment. The level
remained unchanged in 3.5% of the patients and had a drop in 39.2%. Our findings suggest
that PRL may be more than an acute-phase reactant alone. Larger studies are needed to
further elucidate the role of PRL in patients with HF. Research regarding the treatment of
patients suffering from HF with high levels of PRL post-GDMT of HF with bromocriptine
may have consequences like those in peripartum cardiomyopathy.