Late-night habits linked to higher bipolar and emotional risks, study finds

A new study has examined the link between sleep patterns and mental health in over 2,000 Italian adults. Researchers found that those who stay up late—known as evening chronotypes—face a higher risk of emotional and mood-related issues. The findings suggest sleep habits may play a key role in bipolar vulnerability and emotional regulation. The study involved 2,031 adults, with 22.8% identified as evening types, 22.2% as morning types, and the remaining 55% as neutral. Evening chronotypes showed significantly higher rates of emotional dysregulation compared to morning and neutral groups. They also scored higher on traits linked to depressive, anxious, irritable, and cyclothymic temperaments.

Eveningness was strongly associated with greater emotional-regulation difficulties and higher scores on bipolar vulnerability assessments. These included the Mood Disorder Questionnaire (MDQ) and the Hypomania Checklist (HCL-32-R2). In contrast, good or excellent sleep quality appeared to reduce the risk of subthreshold bipolar disorder.

When analysing multiple factors, only evening chronotype and tobacco use remained strong predictors of bipolar-related features. The results align with broader trends, as roughly one in three adults in the UK and similar proportions across Europe identify as night owls. The research highlights a clear connection between late-night habits and mental health risks. Evening chronotypes exhibit more emotional dysregulation and bipolar vulnerability markers than other groups. Meanwhile, better sleep quality may offer some protection against these issues.