Abstract
Background
Prior to the initial 2020 lockdown in Aotearoa New Zealand, respiratory disease hospitalisation patterns showed a clear and disproportionate burden for vulnerable populations. The lockdown implemented on 26 March 2020 to control COVID-19 in the community brought about an overnight switch to life as it was known by most, with major restrictions to all movements outside of one’s dwelling. Because of the similar transmission characteristics, lockdown has been proposed as protecting against infectious respiratory diseases other than COVID-19, in turn preventing exacerbation of chronic respiratory conditions. International literature related to respiratory disease hospitalisation rates during lockdown supports this hypothesis, and a decrease in population hospitalisations during lockdown has been reported in a wide range of global contexts. However, public health strategies often fail more vulnerable populations, and these failures can remain hidden when reporting on the total population. Further research is required to understand the impact of lockdown on respiratory disease hospitalisations for vulnerable populations in Aotearoa New Zealand.
Aims
The aim of this research was to investigate the impact of the 2020 lockdown (26 March – 27 April) on respiratory disease hospitalisation rates and inequity patterns in Aotearoa New Zealand.
Methods
Nationwide public hospital admissions for non-COVID-19 respiratory disease as a primary diagnosis between 26 March and 27 April were compared between 2015-2019 and 2020. Hospitalisation rates were also compared by groups based on ethnicity, age, socioeconomic status, and sex. Analyses were repeated for specific respiratory conditions of interest: asthma, bronchiectasis, bronchiolitis, COPD, influenza, pneumonia, and upper respiratory tract infections. Analyses of the severity hospitalisations and extraneous confounders were also performed.
Results
New Zealand people were 50% less likely to be hospitalised for a non-COVID-19 respiratory disease hospitalisation during the 2020 Alert Level 4 Lockdown compared to the same period in 2015-2019. Ethnicity groups were compared to the reference group ‘European/other,’ which included all hospitalised cases who did not identify as Māori, Pacific Peoples, Asian, or Middle Eastern/Latin American/Hispanic/African. Adjusted relative rate ratios show that the reduction for the Māori population was not statistically different to European/other. However, the reduction for Pacific Peoples was smaller than European/other, and reductions for Asian Peoples and Middle Eastern/Latin American/Hispanic/Africans were significantly larger than European/other. Although there was a significant reduction in total population hospitalisation rates for asthma, bronchiolitis, bronchiectasis, COPD, influenza, pneumonia and URTI, reductions were not observed for all population subgroups, and some groups experienced larger reductions than others. Reductions varied by age category, with larger reductions occurring for children aged ‘under 5 years’ and ‘5-14 years’, and smaller reductions occurring for adults aged ‘45-54 years’ and ‘55-64 years’. Additional analyses indicate that the increase in severity of hospitalisations during the lockdown was different across groups, with particular concern for Pacific Peoples, Asian Peoples, and people aged ‘15-24 years’.
Discussion
Lockdown was associated with a reduction in total population respiratory disease hospitalisations. This association suggests that lockdowns are effective in reducing non-COVID-19 respiratory disease hospitalisations, allowing resources to be conserved for pandemic management. The observed reduction in hospitalisations was likely due to a combination of factors including reduced community transmission of respiratory infections, increased barriers to accessing health services, and changes to typical health service processes. However, some groups experienced widening inequities during lockdown, evident in smaller reductions to hospitalisation rates and increased severity in the hospitalisations that did occur. Future pandemics require improved strategies to ensure health needs are being met for vulnerable groups during restrictions.