As she did in 2011, Oscar- and Tony Award-winner Catherine Zeta-Jones has checked herself in to a treatment facility to battle bipolar disorder.

Zeta-Jones' spokeswoman, Sarah Fuller, told The Associated Press in an email Tuesday that the actress, 43, "is committed to periodic care in order to manage her health in an optimum manner."

advertisement | advertise on newsday said Zeta-Jones entered a facility Monday for a 30-day program.

Bipolar disorder, also known as manic-depressive illness, is characterized by severe shifts in mood, energy, activity levels and the ability to carry out day-to-day tasks, according the National Institute of Mental Health. There is no cure for the lifelong and recurrent illness, but most sufferers respond to a maintenance treatment plan that includes medication and psychotherapy.

Zeta-Jones has bipolar II, which the NIMH calls a milder form that occurs in about 1 percent of the population.

Zeta-Jones has been married for 11 years to actor Michael Douglas.