  We study scalar glueballs and scalar mesons at $T \neq 0$ in the soft wall
holographic QCD model. We find that, using the Anti-de Sitter-Black Hole metric
for all values of the temperature, the masses of the hadronic states decrease
and the widths become broader when T increases, and there are temperatures for
which the states disappear from the scalar glueball and scalar meson spectral
functions. However, the values of the temperatures in correspondence of which
such phenomena occur are low, of the order of 40-60 MeV. A consistent
holographic description of in-medium effects on hadron properties should
include the Hawking-Page transition, which separates the phase with the Anti-de
Sitter metric at small temperatures from the phase with Anti-de Sitter-Black
Hole metric at high temperatures.
