Midlife satisfaction and sleep quality

Life Satisfaction Affects Sleep in Midlife

Megan Brooks

June 15, 2015

 

SEATTLE, Washington — Middle-aged adults who are more satisfied with their life are apt to fall asleep faster than their less satisfied peers, a new study hints.

In analyzing survey data from 3950 adults who took part of the Midlife in the United States II (MIDUS-II) study, researchers found that those with higher life satisfaction reported shorter sleep-onset latency (SOL).

"Life satisfaction is interlinked with many measures of sleep and sleep quality, suggesting that improving one of these variables might result in improvement in the other," lead author Hayley O'Hara, recent graduate of Ohio Northern University in Ada, told Medscape Medical News.

She presented her research, conducted under the supervision of Megan Clegg-Kraynok, PhD, at Ohio Northern, here at SLEEP 2015: the Annual Meeting of the Associated Professional Sleep Societies.

A Hectic Time

In the MIDUS-II study, a 6-item life satisfaction survey was used to group participants as having low, medium, and high levels of satisfaction, and a subjective measure of minutes it takes to fall asleep was used to measure SOL. Participants had a mean age of 57 years, and 55% were women.

"I was interested in the midlife in the MIDUS-II dataset as they managed to collect a great amount of data from a population that is not as well studied," O'Hara said in an interview. "Midlife is a busy time in one's life with family, jobs and other responsibilities that make it difficult to recruit for any kind of research."

A review of the literature suggests there is a lot of research on well-being and sleep deprivation, she noted, "but not much within the facet of life satisfaction. Life satisfaction is one of many factors that are contained within well-being."

A one-way analysis of variance showed that the effect of satisfaction on SOL was significant (P < .001), with low life satisfaction related to delayed sleep onset during midlife, she reported.

Respondents with higher life satisfaction reported shorter SOL, and only those with high life satisfaction were within the normal range of SOL. "Sleep-onset delay among those with low life satisfaction could be the result of worry and anxiety," O'Hara said.

"This poster is fantastic. It's simple but it has a lot to say," Christopher Winter, MD, medical director of the Martha Jefferson Hospital Sleep Medicine Center in Charlottesville, Virginia, and member of the American Academy of Sleep Medicine, noted in an interview with Medscape Medical News. "It shows that how happy you are with your life correlates with how long it takes you to fall asleep," he said.

"If your house is being foreclosed on or your wife is cheating on you and you have a lot of things on your mind, it may take you a little while to fall asleep and but that's okay. The problem is that often these people will go to bed not when they are sleepy, but when they want to be done with the day," Dr Winter said.

He also said having some trouble falling asleep is not a reason to turn to sleeping pills. "People want to be able to control their sleep like a switch. When they get in bed at night at 11 pm, they want to fall asleep immediately. If they're awake for more than 5 minutes thinking about their life, they get depressed," Dr Winter commented.

"Some people get a powerful negative feeling when it takes them an hour or so to fall asleep," he added. "They think it's a problem, so much so that wanting to escape that negative feeling can easily make people commit to taking sleep pills for the rest of their lives. That's why a lot of people drink themselves to sleep, they want to check out quickly. If they don't, they see it as a failure," Dr Winter said.

A "key" message for these people: "worry less about it," he concludes.

The MIDUS II study is funded by the National Institute on Aging. The authors and Dr Winter have disclosed no relevant financial relationships. 

SLEEP 2015: Annual Meeting of the Associated Professional Sleep Societies. Poster 84. Presented June 8, 2015.

Fermented foods and anxiety

Social Anxiety? Fermented Foods May Help

Megan Brooks

June 15, 2015

 

A diet rich in fermented foods and beverages likely to contain probiotics may help curb social anxiety in young adults, especially those who are highly neurotic, new research suggests.

"While our study cannot definitely determine a causal relationship between fermented food consumption and social anxiety, in combination with the preclinical and clinical studies, our findings suggest that eating more fermented foods can decrease social anxiety," Matthew Hilimire, PhD, an assistant professor in the Department of Psychology, College of William and Mary, Williamsburg, Virginia, told Medscape Medical News.

"Future studies could test potential applications, such as supplementing drug or cognitive-behavioral therapy with fermented foods," he said.

The study was published in the August 15 issue of Psychiatry Research and is available online.

Gut-Brain Interaction

The study included 710 students enrolled in introductory courses in psychology at the College of William and Mary. The participants completed questionnaires about fermented food consumption, neuroticism, and social anxiety.

The questionnaire asked about a variety of foods, including yogurt; kefir or food or beverages that contain yogurt; soy milk; miso soup; sauerkraut; dark chocolate; juices that contain microalgae; pickles; tempeh; and kimchi.

"Not all of these foods necessarily had active cultures, but they have the potential to contain probiotics and bioactive peptides," Dr Hilimire said.

In an interaction model that controlled for demographics, general consumption of healthful foods, and frequency of exercise frequency, the researchers found that exercise frequency, neuroticism, and fermented food consumption significantly and independently predicted social anxiety.

Fermented food consumption also interacted with neuroticism in predicting social anxiety. That is, in students with high degrees of neuroticism, a higher frequency of fermented food consumption correlated with fewer symptoms of social anxiety.

These observations are in line with previous preclinical and clinical trials suggesting that probiotics can have an anxiolytic effect, the researchers say. However, this is the first study to examine the relationship between probiotics and social anxiety, they point out.

"Our study was not able to address the mechanisms because it was a survey of normal eating patterns, social anxiety, and personality. However, previous preclinical studies have suggested potential mechanisms," Dr Hilimire told Medscape Medical News.

"For example, probiotics reduce the permeability of the gut, so harmful substances don't leak out. Probiotics also reduce inflammation of the gut. Because anxiety is often accompanied by gastrointestinal symptoms, reducing gut inflammation helps alleviate those symptoms," he explained.

"Probiotics have also been shown to modify the body's response to stress, and stress response is highly linked to mental health disorders, such as social anxiety. In addition, consumption of fermented milk has been shown to reduce the brain's response to negative facial expressions. By reducing the brain's response to negative social stimuli, social anxiety symptoms might be reduced," Dr Hilimire noted.

Public Health Implications

Commenting on the findings for Medscape Medical News, Bonnie J. Kaplan, PhD, who studies nutrition and mood at the University of Calgary, in Alberta, Canada, said research on the gut microbiome is expanding enormously, as is research on genetic influences on mental disorders.

"This study is interesting in how it ties together several relevant threads of personality, food intake, and exercise ― specifically, personality traits presumed to reflect genetic predisposition, such as neuroticism, a measure of social phobia and anxiety, reported exercise levels, and dietary intake of fermented foods as well as fruits and vegetables."

"Also of interest is the fact that the information was not collected from a clinical sample of people with diagnosed anxiety disorders...participants were first-year psychology students in an American liberal arts university. This means the results have implications for broad, population health," said Dr Kaplan.

"The authors interpret their results as indirect evidence that probiotics (assumed to be in the fermented foods) are combating anxiety. This final point is an inference that will need further research," she added.

As reported previously by Medscape Medical News, Dr Kaplan's own research has shown a strong link between higher levels of nutrient intake and better mental health ― adding to the growing body of evidence demonstrating the critical role of diet in mood disorders.

The authors and Dr Kaplan report no relevant financial relationships.

Psychiatry Res. 2015;228:203-208. Abstract