P25 – A regression discontinuity analysis of the social distancing recommendations for older adults in Sweden during COVID-19

3. Epidemiologi

Carl Bonander1, Debora Stranges2, Johanna Gustavsson3, Matilda Almgren4, Malin Inghammar5, Mahnaz Moghaddassi6, Anton Nilsson2, Paul W. Franks7, 8, Maria F. Gomez9, Tove Fall10, Jonas Björk2, 4

1 Health Economics & Policy, School of Public Health & Community Medicine, Sahlgrenska Academy, University of Gothenburg, Sweden
2 Division of Occupational and Environmental Medicine, Lund University, Lund, Sweden
3 Centre for Societal Risk Research, Karlstad University, Sweden
4 Clinical Studies Sweden, Forum South, Skåne University Hospital, Lund, Sweden
5 Department of Clinical Sciences Lund, Section for Infection Medicine, Skåne University Hospital, Lund University, Lund, Sweden
6 Social Medicine and Global Health, Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
7 Lund University Diabetes Center, Department of Clinical Sciences, Skåne University Hospital, Malmö, Sweden
8 Harvard Chan School of Public Health, Boston, MA, USA
9 Department of Clinical Sciences in Malmö, Diabetic Complications Unit, Lund University Diabetes Centre, Sweden
10 Department of Medical Sciences, Molecular Epidemiology, and Science for Life Laboratory, Uppsala University, Sweden

Bakgrund: We investigate the impact of a non-mandatory and age-specific social distancing recommendation on isolation behaviors and disease outcomes in Sweden during the first wave of the COVID-19 pandemic. The policy stated that people aged 70 years or older should avoid crowded places and contact with people outside the household.

Metod: We used a regression discontinuity design—in combination with self-reported isolation data from COVID Symptom Study Sweden (n = 96,053) and national register data on COVID-19 hospitalizations, deaths, and confirmed cases—to estimate the effects of the policy.

Resultat: Our primary analyses showed a sharp drop in the weekly number of visits to crowded places (-13%) and severe COVID-19 cases (-16%) at the 70-year-threshold. These results imply that the age-specific recommendations prevented approximately 1,800 to 2,700 severe COVID-19 cases, depending on model specification.

Slutsats: It seems that the non-mandatory, age-specific recommendations helped control COVID-19 disease during the first wave of the pandemic in Sweden, as opposed to not implementing a social distancing policy aimed at older adults. Our study provides empirical data on how populations may react to non-mandatory, age-specific social distancing policies in the face of a novel virus.