Publications

Our sleep–wake rhythm is determined by the interaction of our work–life balance, that is, the ‘social clock’, and our biological clock. After retirement, the social restrictions generally loosen up, possibly giving more room for our genetic predispositions to regulate the sleep–wake rhythm. In this study, we investigated shifts in wake-up times and chronotypes during employment and retirement. We used data from 20,189 participants from the Netherlands Twin Register. We applied a mixed-effects model to test whether the type of day (working day or non-working day) is a predictor of wake-up time in early birds and late risers. Next, we performed a regression to assess the prevalence of chronotypes in employees and retirees. Then, we tested whether the two groups differed in their wake-up times on working days and non-working days using quantile regression. Finally, we used polygenic scores for morningness to predict the variance in chronotype in employees and retirees. Both early and late risers have later wake-up times on non-working days compared to working days. Employment status was not a predictor of chronotype, but rather of wake-up time on working days. The effect of the polygenic score for morningness on chronotype did not depend on employment status. Our study showed that the social clock influences wake-up time on working days, but not chronotype, making chronotype a relatively stable trait. Additionally, the social clock does not suppress the genetic predisposition for chronotype. These analyses enhance our understanding of how both society and genetics influence our chronotype and sleep–wake rhythm.

The introduction of artificial lighting provoked a form of circadian misalignment called social jetlag: the misalignment between the biological clock and the social clock. The literature has focused on the association with negative mental health in students, while knowledge on the association with wellbeing in adults is limited. The sample included 20.143 participants from the Netherlands Twin Register (NTR). Linear regression models were applied to assess the association between sleep-corrected social jetlag and the wellbeing factor score, and the interaction effects of age and week day. Additionally, a within-family analysis was performed to correct for the effect of the family environment. We found a weak but significant negative correlation between social jetlag and the wellbeing scales (r = −0.05). The association between social jetlag and wellbeing was marginal (β = −0.05, R2 = 0.22 %, p < 0.001, N = 7456) and did not depend on age or week day. The within-family design showed no confounding by family effects. Our results indicate that social jetlag should not be a primary concern for wellbeing in adults. Future studies should focus on using objective measures for social jetlag and use longitudinal data to disentangle short term and long term results.

These guidelines have been developed within the framework of the EU Horizon 2020 ENLIGHTENme project: Innovative policies for improving citizens’ health and wellbeing addressing indoor and outdoor lighting. It represents the result of the collaborative endeavour involving 22 partners from different EU and non-EU countries. It aims to advance the understanding of how indoor and outdoor lighting affects health and wellbeing, particularly in elderly populations. It presents innovative, evidence-based guidelines and policies for measures, technologies, and interventions that can be implemented with a dedicated Decision Support System to help both citizens and city leaders improve public health and wellbeing.

Outdoor lighting is an element featuring the urban environment that is becoming more and more relevant for urban planning, both in terms of influencing citizens’ health and wellbeing as well as the inclusiveness of people living in cities. While urban studies have already extensively investigated urban quality and liveability, there is still little attention on urban lighting as a relevant feature for ensuring high quality urban realms. Moreover, urban lighting can affect health and wellbeing of people and especially of the most vulnerable group of older adults. They suffer more than others not only of the lack of basic services such as public transport, but also of the inappropriate urban lighting that affects their social life, health and wellbeing.

The paper describes a method for including urban lighting as a factor for assessing urban quality, basing on the selection and mapping of key and easy to use indicators. The selected indicators have been tested in three European cities with different features in terms of latitude (that influence natural lighting and therefore the amount of exposure to artificial lighting), urban environments and lighting systems: Amsterdam (The Netherlands), Bologna (Italy), and Tartu (Estonia). The selection has been affected by data availability especially in the lighting domain, highlighting the need of deepening the composition of key lighting indicators at different urban scales.

The developed method allows to support policy makers in taking decisions about where and how to redesign the public lighting systems introducing health and wellbeing as a transversal issue to consider in every public policy.

Come sottolineato da Zielinska-Dabkowska (2019), al momento non esiste una definizione e un approccio condiviso a livello internazionale per il masterplan dell'illuminazione urbana (Urban Lighting Masterplan, ULM). Essendo uno strumento piuttosto recente, le sue strutture e gli obiettivi sono influenzati da vari fattori, dalla presenza di diversi professionisti coinvolti nel progetto di illuminazione urbana, dai vari lessici utilizzati e, infine, dalle differenze linguistiche. Tuttavia questi strumenti stanno attirando sempre più l'attenzione delle città, diventando un punto di riferimento per varie politiche urbane. Pertanto, individuare caratteristiche distintive e comuni, definendo i suoi scopi, obiettivi e contenuti ricorrenti, può costituire un valido riferimento per le città che intendono implementare questo tipo di piano.

Questo contributo intende fornire una panoramica iniziale dello stato dell'arte dei piani illuminotecnici, per identificare approcci comuni e temi ricorrenti, ma anche per comprendere in che termini la questione della salute e del benessere delle persone viene presa in considerazione. Pertanto, attraverso una revisione comparativa dei piani illuminotecnici e dei masterplan sia a livello europeo che non europeo, è possibile individuare e comprendere i temi più ricorrenti e quelli emergenti, con particolare attenzione alla salute e al benessere umano. La ricerca fa parte del progetto ENLIGTHENme, finanziato dalla Commissione Europea nell'ambito del programma Horizon2020, che ha tra i suoi obiettivi quello di orientare le politiche urbane volte a promuovere la salute e il benessere delle persone attraverso la luce artificiale sia urbana che indoor.

En el marco del proyecto europeo ENLIGHTENme se ha desarrollado una plataforma web georreferenciada multiescalar que analiza la vulnerabilidad de las personas en torno a la iluminación en tres ciudades europeas. El objetivo del proyecto es desarrollar políticas innovadoras para mejorar la salud y el bienestar de la ciudadanía a través de la iluminación. En ese marco, la plataforma sirve de apoyo en diferentes estadios del proyecto: primero para la selección de los distritos a analizar, y posteriormente, para contextualizar los análisis clínicos que se realizan con una muestra de personas mayores de estos distritos. Dicha plataforma combina mapas temáticos en 2D accesibles desde un visor web de información georreferenciada basado en Azure Maps, con el modelo 3D de los distritos seleccionados sobre un visor desarrollado sobre Cesium. Para los mapas 2D se generan indicadores de vulnerabilidad social, urbana, de iluminación y de salud, sintetizándolos en índices por dominio y en un índice combinado para seleccionar los distritos vulnerables. Sobre estos distritos se analiza a escala intraurbana la iluminación artificial y la iluminación natural a través de procesado de información satelital y LiDAR. Por otro lado, se modelan los edificios del distrito en 3D, asignándoles sus características básicas y calculando indicadores relativos a la iluminación natural interior de las viviendas a partir de sus características geométricas.

Due to the dominant presence of studies and reviews exploring the impact of light on physical and mental illness, studies specifically investigating the effect of light on wellbeing are often overshadowed. The aim of this review is to give an overview of specifically these studies conducted on light and wellbeing, and to summarize the reported effects. After a literature search in PubMed, PsycInfo, and Web of Science, 74 studies were found eligible to be included in this systematic review, i.e. they included surveys assessing wellbeing, happiness, life satisfaction, positive affect, or quality of life. Of these 74 studies, 30 were included in the meta-analysis and assessed for their risk of bias. The meta-analysis showed a pooled effect size of 0.46 (CI = 0.29–0.62), indicating that light has a small-to-moderate positive effect on wellbeing. After removing outliers and studies with a high risk of bias, the sensitivity analysis showed the pooled effect size to be robust (0.53, CI = 0.35–0.72). Although the sensitivity analysis indicated a robust effect, the results might still be biased due to the relatively small sample sizes, risk of bias in the designs (due to e.g. difficulties handling confounders and the reporting of the outcomes), and publication bias. We encourage future studies to replicate these positive results in larger samples, and to give extensive details about the light design and statistical outcomes, to increase the number of studies that can be included in these types of systematic reviews.

The association between circadian rhythms and diseases has been well established, while the association with mental health is less explored. Given the heritable nature of circadian rhythms, this study aimed to investigate the relationship between genes underlying circadian rhythms and mental health outcomes, as well as a possible gene-environment correlation for circadian rhythms. Polygenic scores (PGSs) represent the genetic predisposition to develop a certain trait or disease. In a sample from the Netherlands Twin Register (N = 14,021), PGSs were calculated for two circadian rhythm measures: morningness and relative amplitude (RA). The PGSs were used to predict mental health outcomes such as subjective happiness, quality of life, and depressive symptoms. In addition, we performed the same prediction analysis in a within-family design in a subset of dizygotic twins. The PGS for morningness significantly predicted morningness (R2 = 1.55%) and depressive symptoms (R2 = 0.22%). The PGS for RA significantly predicted general health (R2 = 0.12%) and depressive symptoms (R2 = 0.20%). Item analysis of the depressive symptoms showed that 4 out of 14 items were significantly associated with the PGSs. Overall, the results showed that people with a genetic predisposition of being a morning person or with a high RA are likely to have fewer depressive symptoms. The four associated depressive symptoms described symptoms related to decision-making, energy, and feeling worthless or inferior, rather than sleep. Based on our findings future research should include a substantial role for circadian rhythms in depression research and should further explore the gene-environment correlation in circadian rhythms.

Arredo & Città, the magazine of the NERI foundation, based in Italy, has dedicated its entire first issue of 2023 to the ENLIGHTENme project. Seven in-depth articles, authored by different members of the ENLIGHTENme consortium, introduce the breadth and depth of the ENLIGHTENme research in investigating the role indoor and outdoor lighting has on people's health and wellbeing. The articles of the magazine cover:

• The stars look down, but we don’t see them. Philosophical and ethical aspects of urban lighting by Mirko Ancillotti, Deborah Mascalzoni
• Towards innovative urban lighting policies. The ENLIGHTENme project by Elisa Conticelli, Giulia Marzani, Simona Tondelli
• The impact of lighting on people’s health and wellbeing. A multidisciplinary approach by Giulia Marzani, Elisa Conticelli, Peter Liljenberg, Sif Enevold, Jasmine van der Pol
• Lighting for better ageing by Elettra Bordonaro, Joanne Entwistle, Don Slater
• Building knowledge about lighting for health and wellbeing by Aitziber Egusquisa Ortega, Don Slater, Giulia Marzani
• ENLIGHTENme: how light affects our health and wellbeing by Francesco Nardi, Martina Romagnoli, Chiara La Morgia, Laura Maria Beatrice Belotti, Elisa Baldin, Flavia Baccari, Leonardo Caporali, Giulia Amore, Corrado Zenesini, Luca Vignatelli, Eleonora Pizzi, Alberto Pasti, Valerio Carelli, Francesco Nonino
• Visual and non-visual effects of lighting by Laura Bellia

The articles are available in both English and Italian.

The proceedings collect contributions presented during the international conference “Shaping light for health and wellbeing in cities”, organised in the framework of the Horizon2020 ENLIGHTENme project. The conference has investigated the multifaceted consequences light has on life in cities by adopting a multidisciplinary and integrated approach to explore the complexity of challenges urban lighting poses on health and wellbeing, urban realm and social life. The papers cover several disciplines such as clinical and biomedical sciences, ethics and Responsible Research & Innovation, urban planning and architecture, data accessibility and interoperability, as well as social sciences and economics, and provide multifaceted insights that inspire further explorations. Contributions represent a step towards the development of innovative policies for improving health and wellbeing in our cities, addressing indoor and outdoor lighting.