Today, one-third of Americans over 60 still have at least one living parent. Approximately 5,000 of us turn 65 every day, and demographers report that one out of every eight Americans will be over 65 by the turn of the century.

A wonderful prospect of longevity? Certainly. But while medical advances in recent decades have increased longevity, Americans may be living longer only to enjoy it less. Families are scattered; retirement incomes may be inadequate; crime threatens the elderly physically while loneliness threatens them emotionally.

Often, the burden of care for aging people -- whether their health is good or failing -- falls to their children, who are now middle-aged people, saddled with their own problems. The reversal of roles isn't easy for anyone.

In this book, Robert Cadmus, a retired physician interested in preventive medicine, provides a chatty, practical guide to the care of elderly parents. Many of his recommendations are plain common sense -- supply your parents' home with smoke alarms; make sure they eat balanced meals; follow the directions for using their prescription medicines; and help them keep busy to avoid depression.

Others are more subtle, geared to helping people preserve their aging parents' dignity and independence while providing for their safety and health. Support for one's aging parents "includes more than just food and shelter," Cadmus writes. "It must include love, challenge, encouragement, and an acknowlegement of a person's worth -- past, present, and future."

In a chapter titled "Keep 'Em Busy," the author reminds his readers that post-retirement people are candidates for depression and a wide range of psychosomatic illnesses. "Activity reduces morbidity the incidence of illness " he reminds us. He suggests seven avenues to avoid inactivity:

Continue to work; volunteer for something -- perhaps Nancy Reagan's pet project, the federally sponsored Volunteer Grandparents Program; engage in politics; get more education; enjoy recreational activities; pursue a hobby or craft; keep in touch with family and friends.

Cadmus suggests that aging parents might be charged with compiling a family history. "A family separated by time and distance is surprisingly fragile," he writes, "and to stay strong it needs the glue of communicaton that only a family chronicler can provide." Keeping them busy, he concludes, is the best way of caring for your aging parents.

Other chapters outline medical problems typical to the elderly, discusses drugs and nutrition, suggests ways of dealing with finances, and considers the role of religion in an aging person's life.

Cadmus takes on the frightening experience of being moved out of familiar surroundings in a chapter titled "Homes Away From Home." Ironically, changes of living space may become necessary for aging parents just at the point at which they are least able to face disruption. But take heart. "You will find that most of them will eventually adjust to their new environment with surprising grace," Cadmus writes.

While Cadmus' tone tends toward the slightly patronizing -- at times it's reminiscent of "Father Knows Best" -- his advice is sage, his attitude toward the elderly compassionate, his data up-to-date. This well-organized handbook should help middle-aged people distracted with concerns of their own remember the problems their parents face as the inevitable aging process renders them more dependent on others -- and cope with them effectively.