Chronotype and Mental Health: Recent Advances

Abstract

While evening chronotype is most consistently associated with severity of mood disorder symptoms, emerging evidence implicates evening chronotype as a transdiagnostic correlate of substance use severity, anxiety symptoms, attentional difficulties, and maladaptive behaviors such as aggression. Longitudinal studies point to the possibility that evening chronotype precedes problematic substance use, depression, and anxiety. Neural processes related to reward and affective regulation may underlie associations between evening chronotype and illness. The literature on chronotype and mental illness has evolved to (1) include associations with a broader range of psychiatric symptom profiles; (2) explore underlying mechanisms; and (3) expand on earlier research using objective measures and more sophisticated study designs. In addition to further mechanistic research, additional work is needed to examine the stability and key subcomponents of the chronotype construct, as well as more attention to pediatric and special populations. This research is needed to clarify the chronotype-mental health relationship, and to identify how, when, and what aspects of chronotype can be targeted via therapeutic interventions.

Clock gene polygenic risk score and seasonality in major depressive disorder and bipolar disorder

“…However, it is interesting to notice the significant correlation between the chronotype‐PRS and the MDD‐PRS and BD‐PRS, suggesting that patients with higher scores for a morning type chronotype present lower risk scores for both mood disorders. These results are in line with previous evidence showing that the chronotype most commonly associated with MDD and BD is the evening type 61 …”

Do chronotype differences and night eating syndrome affect dental health?

“…29 Secondly, the mediating factor for the development of periodontal disease may be that E-types have more problematic eating habits such as skipping breakfast, coffee consumption and night eating and are more prone to smoking and alcohol and substance use. 17,[30][31][32] Finally, recent studies indicated that periodontal disease may be associated with psychological factors such as stress, depression and anxiety and these findings may be an indicator that periodontal disease will develop more easily in E-types individuals who experience these psychological symptoms more than M-types. [33][34][35] Although no correlation was found between chronotype preferences and the DMFT index, and number of endodontically treated teeth in our study, a statistically significant relationship was found with the MEQ scores and severity of periodontal disease.…”

Night work and postpartum depression: a national register-based cohort study

“…Further, we lacked information on chronotype. The evening chronotype, which is normally more frequent among night than day workers, has been independently associated with the risk and severity of depression (57). This might have biased the results towards the null if workers with evening chronotype, rather than other chronotypes, tended to change working schedules to non-night work due to depressive symptoms.…”