A report by three geriatric psychiatrists suggests mental illness, not economic need, may be what prompts some previously law-abiding elderly people to begin shoplifting late in life.

In those cases, shoplifting may be a symbolic attempt to compensate for the loss of a spouse, job, health or independence, they reported in the June issue of "Hospital and Community Psychiatry.""Certainly we don't want to say that all people who are shoplifting are mentally ill. But this is a possible thing to consider when somebody with no history of this starts shoplifting for no apparent reason," said Dr. Elliott Stein, a Miami Beach psychiatrist who wrote the report with Dr. Gary Moak of the University of Massachusetts Medical School and Dr. Ben Zimmer of the University of Pittsburgh School of Medicine.

Overall, shoplifting is most common among adolescents and least common among the elderly. In a 1987 study of 932 shoplifting apprehensions at 391 southern California supermarkets, only 8.8 percent were over 60, although that age group makes up 16.7 percent of the area's population.

Those rates have been consistent for the last 25 years, said Roger Griffin, an analyst for Commercial Service Systems Inc., a retail loss prevention firm in Van Nuys, Calif.

"This refutes the suggestion that there are a lot of people out there on fixed incomes forced into shoplifting because of need. Shoplifters in general are not hungry people out there stealing because they are starving," Griffin said.

The doctors said other sociologic data also fails to support the common-sense hypothesis that shoplifting by the elderly is due to economic hardship.

They concluded first offenders over 60 should undergo pretrial psychiatric evaluation if they have no history of criminal behavior and if there is no apparent reason for them to steal.

Their report was based on a study of 10 elderly shoplifters who were already psychiatric patients or who were referred to them by the courts.

In all the cases, economic need was not a factor and shoplifting was linked to various mental illnesses that reduced the ability to inhibit the urge to steal.

"Children commonly shoplift. Somehow on the way to growing up, most people learn to inhibit the desire to take things. Normally that's a function of the nervous system," Moak said.

But that inhibiting function can be impaired by stress, Alzheimers disease, other mental and organic diseases, even certain medications, the doctors said. That disinhibited behavior may be more likely to occur in shops, they noted.

"Stores are set up to encourage people to want to consume merchandise, the assumption being that you are going to go to a cashier and pay for it," Moak said.

"But under a lot of stress those normal inhibitions may be weakened. The nervous system may weaken with age. You've just found out your wife has cancer. You're under a lot of stress. You may experience a lapse and shoplift without planning to."

Shoplifting may also provide a symbolic compensation or retribution, especially if the patient feels unfairly deprived of something or someone he values, the doctors said.

"One of the facts of life of aging is loss - loss of your parents, your spouse, siblings, friends. If you have been forced to retire you lose your career. If you've been forced to move you may have lost your house. If you can no longer drive, you lose a lot of independence," Moak said.

"Those are all things people often take for granted until they reach their senior years. All of a sudden, it's quite serious. The inability to come to terms with them can lead to psychiatric problems, often in the form of depression, often in the form of disturbed behavior," Moak said.

Frequently the stolen items are what Zimmer described as "accoutrements," - jewelry, cosmetics and baubles.

Often, elderly shoplifters are neither criminally charged nor referred for psychiatric treatment, the doctors said.

"You shouldn't ignore it because that kind of disinhibition can be the first sign of a disorder, a sign of things yet to come," Zimmer said.

Treatment may include psychoactive medication, psychotherapy, family counseling, admission to a day program or nursing home, depending on the nature of the problem, he said.

The doctors only had follow-up information on five of the 10 patients in the study, but all five stopped shoplifting after they received additional psychiatric treatment, Moak said. The treatment differed in each case, he said.