Outdoor artificial light at night and risk of early-onset dementia: A case-control study in the Modena population, Northern Italy
Elena Mazzoleni,
Marco Vinceti,
Sofia Costanzini,
Caterina Garuti,
Giorgia Adani,
Giulia Vinceti,
Giovanna Zamboni,
Manuela Tondelli,
Chiara Galli,
Simone Salemme,
Sergio Teggi,
Annalisa Chiari,
Tommaso Filippini
Affiliations
Elena Mazzoleni
Environmental, Genetic and Nutritional Epidemiology Research Center (CREAGEN), Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
Marco Vinceti
Environmental, Genetic and Nutritional Epidemiology Research Center (CREAGEN), Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA
Sofia Costanzini
DIEF Department of Engineering “Enzo Ferrari”, University of Modena and Reggio Emilia, Modena, Italy
Caterina Garuti
Environmental, Genetic and Nutritional Epidemiology Research Center (CREAGEN), Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Department of Medical and Surgical Sciences for Mothers, Children and Adults, Post Graduate School of Pediatrics, University of Modena and Reggio Emilia, Modena, Italy
Giorgia Adani
Environmental, Genetic and Nutritional Epidemiology Research Center (CREAGEN), Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
Giulia Vinceti
Department Center for Neurosciences and Neurotechnology, Department of Biomedical, Metabolic, and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Neurology Unit, Modena Policlinico-University Hospital, Modena, Italy
Giovanna Zamboni
Department Center for Neurosciences and Neurotechnology, Department of Biomedical, Metabolic, and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Neurology Unit, Modena Policlinico-University Hospital, Modena, Italy
Manuela Tondelli
Neurology Unit, Modena Policlinico-University Hospital, Modena, Italy; Primary Care Department, Modena Local Health Authority, Modena, Italy
Chiara Galli
Neurology Unit, Modena Policlinico-University Hospital, Modena, Italy; Primary Care Department, Modena Local Health Authority, Modena, Italy; Department of Neuroscience, Psychology, Pharmacology and Child Health (NeuroFARBA), University of Florence, Florence, Italy
Simone Salemme
Department Center for Neurosciences and Neurotechnology, Department of Biomedical, Metabolic, and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Neurology Unit, Modena Policlinico-University Hospital, Modena, Italy
Sergio Teggi
DIEF Department of Engineering “Enzo Ferrari”, University of Modena and Reggio Emilia, Modena, Italy
Annalisa Chiari
Neurology Unit, Modena Policlinico-University Hospital, Modena, Italy
Tommaso Filippini
Environmental, Genetic and Nutritional Epidemiology Research Center (CREAGEN), Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; School of Public Health, University of California Berkeley, Berkeley, CA, USA; Corresponding author. Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Via Campi 287, 41125, Modena, Italy.
Background: Dementia is a neurological syndrome characterized by severe cognitive impairment with functional impact on everyday life. It can be classified as young onset dementia (EOD) in case of symptom onset before 65, and late onset dementia (LOD). The purpose of this study is to assess the risk of dementia due to light pollution, and specifically outdoor artificial light at night (LAN). Methods: Using a case-control design, we enrolled dementia patients newly-diagnosed in the province of Modena in the period 2017–2019 and a referent population from their caregivers. We geo-referenced the address of residence on the date of recruitment, provided it was stable for the previous five years. We assessed LAN exposure through 2015 nighttime luminance satellite images from the Visible Infrared Imaging Radiometer Suite (VIIRS). Using a logistic regression model adjusted for age, sex, and education, we calculated the risk of dementia associated with increasing LAN exposure, namely using <10 nW/cm2/sr as reference and considering ≥10-<40 nW/cm2/sr intermediate and ≥40 nW/cm2/sr high exposure, respectively We also implemented non-linear assessment using a spline regression model. Results: We recruited 58 EOD cases, 34 LOD cases and 54 controls. Average LAN exposure levels overlapped for EOD cases and controls, while LOD cases showed higher levels. Compared with the lowest exposure, the risk of EOD associated with LAN was higher in the intermediate exposure (OR = 1.36, 95% CI 0.54–3.39), but not in the high exposure category (OR = 1.04, 95% CI 0.32–3.34). In contrast, the risk of LOD was positively associated with LAN exposure, with ORs of 2.58 (95% CI 0.26–25.97) and 3.50 (95% CI 0.32–38.87) in the intermediate and high exposure categories, respectively. The spline regression analysis showed substantial lack of association between LAN and EOD, while almost linear although highly imprecise association emerged for LOD. Conclusions: Although the precision of the estimates was affected by the limited sample size and the study design did not allow us to exclude the presence of residual confounding, these results suggest a possible role of LAN in the etiology of dementia, particularly of its late-onset form.
