ABSTRACT
Background: Light–dark alternation has always been the strongest external circadian “zeitgeber” for humans. Due to its growing technological preference, our society is quickly transforming toward a progressive “eveningness” (E), with consequences on personal circadian preference (chronotype), depending on gender as well. The aim of this study was to review the available evidence of possible relationships between chronotype and gender, with relevance on disturbances that could negatively impact general health, including daily life aspects. Methods: Electronic searches of the published literature were performed in the databases MEDLINE and Web of Science, by using the Medical Subject Heading (MeSH), when available, or other specific keywords. Results: Results were grouped into four general areas, i.e. (a) “General and Cardiovascular Issues”, (b) “Psychological and Psychopathological Issues”, (c) “Sleep and Sleep-Related Issues” and (d) “School and School-Related Issues”. (a) E is associated with unhealthy and dietary habits, smoking and alcohol drinking (in younger subjects) and, in adults, with diabetes and metabolic syndrome; (b) E is associated with impulsivity and anger, depression, anxiety disorders and nightmares (especially in women), risk taking behavior, use of alcohol, coffee and stimulants, psychopathology and personality traits; (c) E has been associated, especially in young subjects, with later bedtime and wake-up time, irregular sleep–wake schedule, subjective poor sleep, school performance and motivation, health-related quality of life; (d) E was associated with lowest mood and lower overall grade point average (especially for women). Conclusions: Eveningness may impact general health, either physical or mental, sleep, school results and achievements, especially in younger age and in women. The role of family support is crucial, and parents should be deeply informed that abuse of technological devices during night hours may lead to the immature adjustment function of children’s endogenous circadian pacemakers.
Acknowledgments
The authors thank Mr Ian Abbott for reviewing and editing the final version of the manuscript. The authors also thank Dr Donato Bragatto, Dr Claudia Righini, Mrs Manuela Zappaterra (Biblioteca Interaziendale di Scienza della Salute, Hospital of Ferrara), Mrs Egizia Zironi and Mrs Silvia Bellotti (Unità servizi interbibliotecari, University of Ferrara) for their valuable and precious collaboration.
Disclosure Statement
There are no financial or potential conflicts of interest by sponsoring agent, products, technology or methodologies used in this report submitted for publication by any of the authors.
Funding
This study has been supported, in part, by a scientific grant from the University of Ferrara (FAR – Fondo Ateneo Ricerca)