This means that it's up to you to gauge your parent's symptoms. The best way to do that, experts say, is to ask nonjudgmental questions — for example, by inquiring about your parent's spirits. Or, to get a sense of energy levels or interest in everyday activities, find out what hobbies provide fun. Other signs of depression include insomnia, irregular eating habits, irritability, and anxiety. If your gentle queries reveal that your parent is suffering from three or more of these problems, an immediate consultation is in order.

Get her the help she needs
Unless your parent has a geriatrician, there's a good chance she sees more than one doctor for various ailments. Most primary care physicians don't feel qualified to diagnose mental disorders, so you'll need to add a psychiatrist to that crew. You will likely need to make the appointment for your parent; even if you live out of town, try to attend that initial consultation so you can hear firsthand what the doctor has to say. Share what you learn with her other doctors, particularly the names and dosages of any medications the psychiatrist may have prescribed.

A diagnosis of depression then pre­sents the question: How do you treat it? Although all known treatment options are available to the elderly, you'll need to factor in your parent's age and physical condition when deciding which to try. For instance, antidepressants are known to work well in this age group. In fact, paroxetine (Paxil) was shown to be more effective than other therapies in depressed patients older than 70, according to a recent study published in the New England Journal of Medicine. But antidepressants have side effects, including dizziness, which can lead to debilitating falls, a leading cause of death in late life.

Similarly, exercise is a proven antidote to depression . A brisk walk three times a week may relieve the symptoms of major depression as well as a common antidepressant does, according to a study review recently published by researchers at Duke University Medical Center. But vigorous exercise isn't possible for someone with a physical disability or reduced mobility. (Of course, even limited exercise will be beneficial, though not effective enough to counter major depression .)

Talk therapy presents its own unique problem: Members of a stoic older generation unaccustomed to talking about their feelings may resist it. But that's a hurdle you should try to help your parent overcome. Explain that talk therapy, when combined with antidepressants , relieves depression long-term. The drugs adjust chemical imbalances in the brain, while the talk therapy teaches patients how to recognize and ward off depression triggers. "The antidepressant gets you to a stable place," says Gary Kennedy, M.D., director of the division of geriatric psychiatry at Montefiore Medical Center in New York City. "But the psychotherapy will keep you there."

Whatever therapy your parent's doctor recommends, you will probably need to formulate a collaborative strategy with a therapist to persuade mom or dad to accept it. According to geriatric psychologist Rasin-Waters, an anxious and moody elderly patient will often resist a doctor's recommended course of antidepressants and talk therapy. That's when you need to express your encouragement, concern — and even some tough love.

Be prepared to appeal to something your parent very likely cares about a lot: her independence. Tell her that, despite your love and concern, depression is a serious illness, and you simply can't take care of her by yourself. Explain to her that if she follows the therapist's advice she will feel better and will not need the extra care and monitoring of, say, an assisted-living facility. The choice is hers.

Rasin-Waters has seen it often: As your parent's dark cloud lifts, she will likely embrace the therapy and enjoy steady improvement. Just remember: You remain the linchpin in this ongoing collaboration. You need the therapist to get your parent the proper treatment, and the therapist needs you to make sure it will be followed. Your parent, of course, needs you both.

Develop a support system
Here's where you'll need to cultivate the kindness of others, whether you live nearby or far away: Your parent's lasting recovery depends on a having a network of help from friends, neighbors, and social-service providers. Try some of these proven strategies:

• Meet the neighbors
  Seek out the people your parent knows and trusts. Introduce yourself and explain your concerns. And ask if you might contact them in an emergency. Keep their phone numbers in your cell phone and on your refrigerator.
  
• Find your parent a dinner partner
  Isolation worsens depression ; people who live alone also tend to eat poorly, accelerating mood problems and infirmity. If you live nearby, you probably already have a regular dinner date with mom or dad. Augment those occasions with help from meals-on-wheels, whose workers are often senior volunteers who will sometimes sit and talk with your parent while she eats. Enlist high school students, who often must fulfill community service requirements at school, to bring over regular meals. Many towns offer senior services through social agencies or churches that will also provide companionship and food.
  
• Get her out and about
  If your parent is healthy but inactive, look online to find local groups, such as "Silver Sneakers," that pair up active seniors in walking , yoga, and other exercise programs. If you live in town, make a regular date to pick up your mom for a walk in the mall and lunch. Or suggest that she volunteer at a hospital, soup kitchen, church, or synagogue.
  
• Listen to her stories
  In his comprehensive studies of the elderly, Robert Butler, M.D., founding director of the National Institute on Aging, found that "life review," or extensive reflection and reminiscence, helps older people find new meaning. Set up a digital camera/recorder and ask your mom to recount her stories. You might say, "We want to preserve our family traditions for your grandchildren and great-grandchildren. Tell us about how you met Dad." Then see what unfolds.
  
• Get mom or dad wired
  If you think your parent is capable of mastering the technology, buy her a computer so you can exchange e-mails regularly. Send your kids over to introduce her to some Web sites that may interest her; even if her frailty limits her contact with her larger community, she can feel a part of a virtual one. At the least, set up a fax machine in your parent's home. Send her special articles, photos, or pictures drawn by your kids — and remind her to keep her appointments. Staying connected, experts say, is one of the most effective ways your parent can prevent the "dark cloud" from descending again and ensure that, on most mornings, her day will dawn brightly.

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