A Systematic Literature Review and Meta-Analysis of the Effects of Lockdowns on COVID-19 Mortality II

Abstract

The purpose of this systematic review and meta-analysis is to determine the effect of lockdowns on COVID-19 mortality based on available empirical evidence. Lockdowns are defined as the imposition of at least one compulsory, non-pharmaceutical intervention (NPI). We employ a systematic search and screening procedure in which 19,646 studies are identified that could potentially address the purpose of our study. After three levels of screening, 32 studies qualified. Of those, estimates from 22 studies could be converted to standardized measures for inclusion in the meta-analysis. They are separated into three groups: lockdown stringency index studies, shelter-in-place-order (SIPO) studies, and specific NPI studies. Stringency index studies find that the average lockdown in Europe and the United States in the spring of 2020 only reduced COVID-19 mortality by 3.2%. This translates into approximately 6,000 avoided deaths in Europe and 4,000 in the United States. SIPOs were also relatively ineffective in the spring of 2020, only reducing COVID-19 mortality by 2.0%. This translates into approximately 4,000 avoided deaths in Europe and 3,000 in the United States. Based on specific NPIs, we estimate that the average lockdown in Europe and the United States in the spring of 2020 reduced COVID-19 mortality by 10.7%. This translates into approximately 23,000 avoided deaths in Europe and 16,000 in the United States. In comparison, there are approximately 72,000 flu deaths in Europe and 38,000 flu deaths in the United States each year. When checked for potential biases, our results are robust. Our results are also supported by the natural experiments we have been able to identify. The results of our meta-analysis support the conclusion that lockdowns in the spring of 2020 had little to no effect on COVID-19 mortality. This result is consistent with the view that voluntary changes in behavior, such as social distancing, did play an important role in mitigating the pandemic.

Descriptive study of causes of death and COVID-19-associated morbidities from the New York City electronic death record: first wave of the pandemic March–July 2020

“…Not only did chronic ischaemic heart disease, hypertension, pneumonia and diabetes display strong statistically remarkable deviations from reference, but these conditions are also prominent morbidities noted in the context of COVID-19 deaths. There is also the possibility that the increase in non-COVID-19 deaths may be partially due to indirect effects related to the pandemic response from several dimensions (eg, incomplete knowledge by healthcare providers of COVID-19 as a novel condition impacting treatment strategies, policy implementation, lockdowns, social and economic dislocations, treatment and lapses in care) 21–28. However, although plausible, our analysis is inadequate to inform on this issue in a dispositive manner.…”

Long COVID as a functional somatic symptom disorder caused by abnormally precise prior expectations during Bayesian perceptual processing: A new hypothesis and implications for pandemic response

“…240 Similarly, closing schools led to severe adverse effects on children's mental health and learning, yet were not effective at reducing the COVID-19 burden. 233,237,[241][242][243][244][245][246][247][248][249][250][251] Not implementing lockdowns (including not closing schools), and explaining that they have a very negative cost-benefit ratio, is important. 233,241 Third, negative media coverage must be replaced with accurate information.…”

“…Second, lockdowns have led to increased anxiety, depression, social isolation, and physical inactivity, yet did not reduce COVID-19 rates or mortality in the population. 233 , 237 – 239 Although physical activity decreased markedly during lockdown, physically active people were less likely, when infected, to report prolonged symptoms (OR 0.24; 95% CI 0.10, 0.55). 240 Similarly, closing schools led to severe adverse effects on children’s mental health and learning, yet were not effective at reducing the COVID-19 burden.…”

Influenza mortality as an indicator of the effectiveness of public health interventions and their impact on United States COVID mortality

“…Furthermore, almost every intervention has, at some point, been declared ineffective, including masking, 7,8 routine testing, 9 school closures, 10 and business "lockdowns". 11,12 Meta-analyses of studies of the efficacy of individual NPIs have tended to find beneficial effects [13][14][15] with a few prominent exceptions. 7,8 Closures of businesses and schools, limits on social gathering, travel restrictions, social distancing rules, masking mandates, and other NPI's act in concert to reduce the transmission of respiratory infections.…”