This article is more than 5 years old. Information may no longer be current.

Obesity, depression increase risks for excessive daytime sleepiness

Obese individuals or those with depression are just as likely as sleep-deprived individuals to experience excessive daytime sleepiness, according to study results.

“Obesity and weight gain predicted who was going to have daytime sleepiness,” Julio Fernandez-Mendoza, PhD, of the Sleep Research and Treatment Center at Penn State College of Medicine, said in a press release. “Moreover, weight loss predicted who was going to stop experiencing daytime sleepiness, reinforcing the causal relationship.”

Fernandez-Mendoza and colleagues conducted a representative longitudinal study of 1,395 adults aged 20 years and older from the Penn State Adult Cohort to determine through polysomnography if there were any predictors of excessive daytime sleepiness (EDS).

Participants were administered medical evaluations and a 1-night polysomnography at baseline and a telephone interview at follow-up, which occurred at an average of 7.5 years.

After follow-up, participants were categorized by their baseline and follow-up results. There were 1,035 participants who had no EDS at baseline nor follow-up, 138 who did not have EDS at baseline but did at follow-up, 147 who started with EDS at baseline but not at follow-up, and 75 who had EDS at baseline and follow-up.

Incidence of EDS was 8.2%. Individuals with depression (OR = 2.8; 95% CI, 1.8-4.5), sleep apnea (OR = 2.2; 95% CI, 1.1 -4.4) and obesity (OR = 2.1; 95% CI, 1.4-3.1) were at an increased risk for incident EDS. Depression (OR = 2.1; 95% CI, 1-4.6) and a BMI increase of 2 kg/m² (OR = 1.1; 95% CI, 1-1.2) were slightly associated with persistent EDS.

The researchers noted weight loss was linked to a decrease in EDS (OR = 2.5; 95% CI, 1.2-5.1), while weight gain was associated with increases in incident (OR = 2.8; 95% CI, 1.8-4.3) and persistent EDS (OR = 2.7; 95% CI, 1.4-5.2).

Fernandez-Mendoza said the results indicate EDS is more than someone being sleep deprived.

“In the medical field, there is widespread belief that if you feel sleepy during the day, it’s because you didn’t get enough sleep,” he said in the release. “We need to start abandoning this idea. If we continue to believe that the only cause of excessive daytime sleepiness is people sleeping too little, we are missing the vast majority of the population.

“The main cause of a sleepy society are an obese society, a depressed society and, to some extent, people who have a physiological disorder. By looking at our patients more closely, we can start personalizing sleep medicine.” – by Ryan McDonald

Disclosure: The researchers report no relevant financial disclosures.