Medication use in populations exposed to the 2010 Eyjafjallajökull eruption: an interrupted time series analysis
Thorarinn Gislason,
Unnur Valdimarsdottir,
Huan Song,
Helga Zoega,
Hanne Krage Carlsen,
Heidrun Hlodversdottir,
Gudrun Petursdottir,
Arna Hauksdottir,
Haraldur Briem,
Throstur Thorsteinsson,
Edda Bjork Thordardottir,
Rebekka Björg Guðmundsdóttir,
Brynjólfur Gauti Guðrúnar Jónsson,
Thorolfur Gudnason
Affiliations
Thorarinn Gislason
Department of Sleep, Landspitali University Hospital Reykjavik, Reykjavik, Iceland
Unnur Valdimarsdottir
Centre of Public Health Sciences, Faculty of Medicine, University of Iceland, School of Health Sciences, Reykjavik, Iceland
Huan Song
3 Med-X Center for Informatics, Sichuan University, Chengdu, China
Helga Zoega
1 Centre of Public Health Sciences, Faculty of Medicine, University of Iceland, Reykjavik, Iceland
Hanne Krage Carlsen
4 Section of Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gotheburg, Sweden
Heidrun Hlodversdottir
1Centre of Public Health Sciences, University of Iceland, Reykjavik, Iceland
Gudrun Petursdottir
Institute for Sustainability Studies, University of Iceland, Reykjavik, Iceland
Arna Hauksdottir
Centre of Public Health Sciences, Faculty of Medicine, University of Iceland, School of Health Sciences, Reykjavik, Iceland
Haraldur Briem
8 Centre for Health Threats and Communicable Diseases, Directorate of Health, Chief Epidemiologis, Reykjavik, Iceland
Throstur Thorsteinsson
9Environment and Natural Resources & Institute of Earth Sciences, University of Iceland, Reykjavík, Iceland
Edda Bjork Thordardottir
Centre of Public Health Sciences, Faculty of Medicine, University of Iceland, School of Health Sciences, Reykjavik, Iceland
Rebekka Björg Guðmundsdóttir
1 Centre of Public Health Sciences, Faculty of Medicine, University of Iceland, School of Health Sciences, Reykjavik, Iceland
Brynjólfur Gauti Guðrúnar Jónsson
1 Centre of Public Health Sciences, Faculty of Medicine, University of Iceland, School of Health Sciences, Reykjavik, Iceland
Thorolfur Gudnason
8 Centre for Health Threats and Communicable Diseases, Directorate of Health, Chief Epidemiologis, Reykjavik, Iceland
Objectives To assess the trends in medication use indicative of physical and psychological morbidity following the 2010 volcanic eruption in Eyjafjallajökull immediately after and during a 3-year period following the eruption.Design Population-based register study.Setting Eyjafjallajökull eruption in Iceland, 2007–2013.Participants All residents in Iceland who received at least one medication dispensing were identified. Residents of exposed areas were classified into exposure groups (individual-level data) and residents in other parts of Iceland were included as a non-exposed group (aggregated data).Intervention/exposure Eyjafjallajökull erupted on 14 April 2010 and continued for 39 days, producing heavy ash fall in South Iceland.Main outcome measures Using interrupted time series analysis, we examined annual and quarterly changes in medicine use, measured as number of dispensed defined daily dose (DDD) per 1000 individuals. We calculated the level shift (immediate change) and change in slope from pre-eruption to post-eruption (long-term change) in medication dispensing.Results Among exposed residents, there was a 6% decrease (95% CI -7% to -4%) in the annual number of dispensed DDDs 1-year post-eruption in the overall medication class, including analgesics (−5%, 95% CI -6% to -3%), hypnotics and sedatives (−9%, 95% CI -11% to -7%) and respiratory medications (−7%, 95% CI -9% to -5%; −8%, 95% CI -11% to -4%). Simultaneously, there was a 9% decrease (95% CI -14% to -4%) in the overall medication class among non-exposed residents. Moreover, among exposed residents, we observed change in slope of −4% (95% CI -7% to -1%) in the overall medication class, including for analgesics (−6%, 95% CI -8% to -3%) and other respiratory drugs (−10%, 95% CI -16% to -4%).Conclusion Our findings indicate that the eruption did not lead to increases in medication dispensing among residents of exposed areas, rather decreases for some medicine classes. The results should be interpreted with caution since the content of each eruption differs.
