When it comes to winter, Atlanta has it relatively well. While a freak, traffic-snarling snowstorm or a Super Bowl weekend ice storm may grab headlines, the average temperatures in even the coldest months of the year can hover around 50 degrees, according to the National Weather Service. The city averages less than 3 inches of snowfall annually, and gets between 9 and 10 hours of sunlight even on the shortest day of the year. Atlanta in winter will never be confused with Buffalo, Chicago or Minneapolis.

But even here, the arrival of the coldest and darkest days of the year can bring about a defined change in some people. Maybe they feel sluggish and don’t want to get out of bed. Maybe they’re easily agitated and quick to anger. Maybe they lose interest in favorite activities and struggle to shake a sense of unhappiness. Maybe they crave carbohydrate-rich foods and put on weight. Maybe they withdraw from friends and family and retreat into a kind of hibernation until the weather warms anew.

Those are all trademark symptoms of seasonal affective disorder (SAD), which according to the National Institute of Mental Health is a recurrent type of depression that typically accompanies the onset of winter, and can last for several months. Although SAD can affect any age group or gender, seniors are among the most vulnerable — particularly those who live alone. They may have limited mobility, and can feel isolated due to the pandemic or for other reasons.

“While SAD can affect adults of all ages, according to the Centers for Disease Control and Prevention, those older than 60 have certain lifestyle and health factors that can put them at a higher risk for all types of depression,” Dr. Paul Kurkjian, a psychiatrist at Miller Children’s and Women’s Hospital Long Beach, California, wrote in the Long Beach Press-Telegram. “This is why it’s especially important that as you age, you constantly stay mindful of your feelings and combat the possibility of experiencing symptoms of depression — especially during the wintertime.”

The chemical connection

Herb Kern was a youthful 63-year-old with a good job as a research engineer, but he felt the change come over him each winter like clockwork: his mood would darken, his energy level would drop and he felt withdrawn from the world. Getting out of bed and getting dressed each morning took additional effort. He did all he could to avoid interacting with others, just wanting to be left alone.

That’s the account Dr. Norman Rosenthal tells in his book “Winter Blues: Everything You Need to Know to Beat Seasonal Affective Disorder.” It was Rosenthal and his team at the National Institute of Mental Health that discovered and named SAD in the early 1980s, with Kern as their breakthrough case. Rosenthal and colleague Alfred Lewy decided to treat Kern using lightboxes to simulate summertime, lengthening his winter days with three extra hours of light before dawn and after dusk.

“Within three days, Herb began to feel better,” wrote Rosenthal, now a professor of psychiatry at Georgetown University School of Medicine, and the worldwide authority on SAD. “The change was dramatic and unmistakable. He was moving into his spring mode several weeks ahead of schedule.”

And ever since, sunlight — or the lack of it — has been viewed as the key element in the onset and diagnosis of SAD. Not surprisingly, incidences of SAD increase with latitude; the shorter the days in the wintertime, the higher rate of its onset. In Georgia, the rate of SAD is about 3.9%, according to Penn State University researcher Kara Duriez, compared to 6.1% in New York and 7.2% in New Brunswick, Canada.

Although much of the academic research into seasonal affective disorder has focused on polar regions, SAD can occur anywhere — even in sunny Florida, where it impacts roughly 1% of the population. And SAD has a cousin known as “winter blues,” which is a milder form of seasonal sadness that does not meet the clinical threshold for depression. Winter blues affects about 10.6 % of people at Georgia’s latitude, according to Duriez, although the symptoms are far more moderate and often go away on their own.

That’s not the case with SAD, a genuine form of depression, which the Cleveland Clinic says impacts 5% of adults in the United States. While it typically first arrives in early adulthood, older adults can face specific risks — not just due to the lack of warm, cheering sunlight, but in how that absence affects the chemicals in their body.

SAD researchers know that the hormone melatonin, secreted by a gland in the brain in response to darkness, has long helped humans regulate their daily and seasonal cycles. The less light during a day, the more melatonin the body may produce and the more tired and sluggish a person may feel. And despite what was once believed, melatonin levels do not decline with age — an American Journal of Medicine study in 1999 found that healthy older men and women had melatonin levels that were similar to those found in younger people.

Lack of sunlight also lowers levels of Vitamin D, which according to Interim Health Care is a nutrient especially important to seniors because it aids in bone health. The lack of it can also heighten depressive symptoms. And then there’s serotonin, a hormone that helps regulate mood. Scientists believe that more sunlight creates more serotonin, improving a person’s feelings of happiness. But in winter, those sunlight levels drop. And as people age, the neutrons that create serotonin become more vulnerable to degeneration, Johns Hopkins researchers found.

“The transporters are lost when these neurons die, and serotonin levels go down,” the Johns Hopkins team wrote in a 2017 study’s news release. “The older they are, the more likely a person is to have lower serotonin levels.”

It can all combine to create a vexing dynamic. Serotonin levels, which help regulate the body’s mood, declining with less sunlight and age. Vitamin D levels dropping due to less sunlight. And then melatonin levels, which promote sleep, remaining elevated due to increased darkness and in spite of advancing age. For some older adults, it’s a recipe for a SAD winter — and that’s before any difficult personal circumstances are added on top.

Pandemic and loss

The twinkling lights and good cheer of the holidays often keep seasonal affective disorder at bay. For many sufferers, it’s not until bleak, cold January — and the beginning of the long, dark haul until spring — when the depression truly sets in. But for older adults who have suffered the loss of a spouse, the holidays can trigger SAD rather than staving it off.

“Because the season is a festive time that is marked by family renewals, a deep sense of loss and mourning can be pervasive when a loved one is missing. … The ‘empty chair’ that was occupied by a wife, parent, other close family members and close and dear friends can often reawaken feelings of grief with renewed intensity,” Dr. Allan Schwartz, a licensed clinical social worker, wrote on the website MentalHelp.net.

“In addition, there is the problem of seasonal changes that come with life during the winter months. Shorter days, fewer hours of sunshine, cloudy skies, cold and damp weather all combine to cause seasonal affective disorder for those (who) are already vulnerable to its influences. In other words, depression can raise its ugly head during time that is supposed to be festive. In fact, it has been my observation that the contrast between the joy that others are feeling and the sadness that one does feel increases the sense of loss and abandonment during this time of year.”

Whether SAD arrives in December or January, though, the results are often the same: withdrawal, loss of interest in friends or activities, sleeping too much and an unshakable sense of sadness. And then there’s the pandemic, which had experts worried about an increased incidence of SAD last winter due to isolation from other people. Those concerns are sure to be heightened again over the winter of 2021-22 due to the stubborn nature of the coronavirus delta variant, which has stoked COVID-19 cases to near-record heights in Georgia.

For older adults, who may be separated from children and grandchildren by distance or have difficulty with mobility, such worries can be even more pronounced. Thankfully, telehealth programs have made consulting with mental health experts easier than ever before. And the same tactic that helped Herb Kern four decades ago remains a tried and true SAD therapy today: exposure to bright light.

We’re not talking about standard indoor lighting, but medical-grade lightboxes far brighter than your living room light bulb. “Indoor illumination is relatively dim, around 50 to 200 lux,” said Dr. Paul Desean, director of Psychiatric Consultation Service at Yale New Haven Hospital in Connecticut, using a measure of light brightness. “Offices are typically 200 to 400 lux, while outdoor light is thousands of lux.” Lightboxes, by contrast, can deliver 10,000 lux.

“Sixty to 80% of SAD suffers benefit from light therapy,” Rosenthal wrote in the journal Psychiatry in 2008. “Mornings seem the best time for light therapy to work, although the treatments can be divided during the day. Most people respond to light therapy within two to four days of initiating treatment. Although the amount of time needed varies, most people need between 30 and 90 minutes ... of light therapy per day.”

Although more severe cases may require the use of antidepressants, experts also encourage several at-home therapies. They include maintaining a regular sleep schedule, taking daily walks, keeping in touch with friends and family members and enjoying energy-boosting foods like coffee, whole grains, beets and dark chocolate. A Chinese study found that playing music can help as well.

A positive attitude toward winter can also help. In 2014, Stanford researcher Kari Leibowitz spent 10 months in Tromsø, Norway, a city 200 miles above the Arctic Circle, and in polar twilight for two months each year. She expected to find residents inactive and depressed; instead, she found them lively, enjoying warm beverages and looking forward to ski season. “They loved the opportunities for coziness provided by the winter months,” she wrote.

Of course, there is no ski season in Atlanta, and winters here can be wet and dank rather than snowy and fairy-tale-like. But Leibowitz left Tromsø believing that in the battle against SAD, state of mind matters. “Being active is part of a happy life — and especially, a happy winter,” she wrote. That’s true in any city and at any age.

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