Not all health problems that occur long-distance are purely physical: Some are psychological as well, and they can be just as difficult to manage.

Elderly relatives, particularly those who are living alone or those who have recently lost a spouse, are vulnerable to depression and other mental illnesses. So, for different reasons, are young adults; for some, a serious mental illness may be triggered by the stress of leaving home to attend college or to live on their own.

That's what happened to Karen Ann Goldberg who, in 1986 at age 22, was hospitalized for depression in North Carolina where she was attending college.

Shortly before she was hospitalized, Goldberg, severely depressed and armed with a cache of sleeping pills, called her mother, who lived in Maryland. "I cried and told her how scared and sad I was, how much I wanted her to come down and help. She flew down a few hours later," recalls Goldberg, who has since graduated from college in Maryland and is applying to medical school. "I was finally convinced that I could not handle my feelings on my own."

While an emotional problem may be less obvious than other illnesses, there are warning signs that family members who are far away can still perceive. "The most important thing is detecting a change in the normal pattern of relating to the person, a lessening of interest in the usual things, a change in their tone, whether warmth or hostility, less ability to handle daily activities. If a relative or friend maintains regular contact, those changes can be conveyed in a telephone conversation," says Darrel A. Regier, director of the division of clinical research for the National Institute of Mental Health.

"Don't write things off as a natural response to moving away from home or aging," says Alan Romanoski, assistant professor of psychiatry at Johns Hopkins Medical Institutions. "An abrupt change in behavior bears following up on."

The level of impairment and its duration are key to determining whether a person is just experiencing normal ups and downs or has a mental illness that requires treatment. If you're concerned, urge that your relative be seen by their primary physician first.

But don't be afraid to push for a referral to a psychiatrist for diagnosis and treatment. Get other professional follow-up, such as psychotherapy or family counseling, as needed.

From a distance, substance abuse may be hard to distinguish from other psychological problems; it may even mask them. "If you have a gut feeling somebody doesn't sound quite right on the phone, it pays to follow up. With most drugs, including alcohol, people will sound and act differently," says Stephen J. Bergman, a Boston psychiatrist.

Suggestions:

Be as alert to psychological complaints as to physical ones. Symptoms of depression include a persistent sadness, loss of interest in ordinary activities, fatigue, sleep and eating disturbances, helplessness, irritability or excessive crying. If mood changes persist for several weeks, push your relative or friend to seek professional help.

Make sure the primary care physician considers the interaction of physical and mental illnesses. In the case of the elderly, for example, sudden forgetfulness should not be taken for granted as a sign of old age. While it may signal dementia or Alzheimer's disease, memory loss is also attributed to depression, overmedication, drug interaction or small strokes, many of which are treatable.

Communicate your concerns by phone or in writing to those treating a relative or friend.

Plan regular visits. "A picture is still worth a thousand words," says Romanoski.