Aug. 4 (Bloomberg) -- Estrogen may ease the symptoms of schizophrenia in women with severe disease, according to an Australian study in the Archives of General Psychiatry.

Researchers started focusing on estrogen's links to schizophrenia about two decades ago when it became clear that female patients typically fell ill an average of about five years after males. Symptoms also tend to worsen after childbirth and menopaus when estrogen levels retreat, and lessen during menstruation and pregnancy when hormones levels are high.

In the study, 56 women given an estrogen patch in addition to standard medications for one month had significantly fewer psychotic symptoms, including hallucinations, delusions and movement disorders, than the 46 women getting a placebo patch. The women were all in the acute or chronic phase of the illness, including 29 who were hospitalized for the condition.

Estrogen ``appears to be a useful treatment for women with schizophrenia and may provide a new adjunctive therapeutic option for severe mental illness,'' wrote the researchers, led by Jayashri Kulkarni, from the Alfred Psychiatry Research Center at Alfred and Monash University in Melbourne. ``Estrogen may have a preventive role in women with schizophrenia whose condition has been known to deteriorate in periods of hormonal change,'' and may also help men, the scientists said.

About 1 percent of people have schizophrenia, a mental disorder that makes it difficult to think logically, behave normally and tell the difference between reality and hallucinations. Medication can control severe symptoms, such as hearing voices or angry or violent outbursts, though the drugs can cause serious side effects including weight gain, diabetes and movement problems.

Best Sellers

The drugs, known as anti-psychotics, were the sixth best- selling class of medications worldwide in 2007. Bristol-Myers Squibb Co.'s Abilify, Johnson & Johnson's Risperdal and Eli Lilly & Co.'s Zyprexa generated $20.7 billion in sales last year, according to IMS Health, a prescription tracking firm in Norwalk, Connecticut.

The estrogen patch didn't help with negative symptoms of schizophrenia, when patients lose their ability to make plans, express emotion and talk with friends. Those symptoms may be less responsive to therapy and require longer-term care, the researchers said.

Larger and longer studies are needed to confirm the benefits of estrogen, which is used to ease the symptoms of menopause and treat osteoporosis, the researchers said. Estrogen pills, made by Wyeth and others, have been linked to strokes and other ailments. Previous studies suggested estrogen patches may be a safer option.

To contact the reporter on this story: Michelle Fay Cortez in Minneapolis at mcortez@bloomberg.net

Last Updated: August 4, 2008 16:59 EDT