COVID-19 has taken a relatively limited toll on the mental health of most people around the world, according to an article published in the BMJ by a research team led by McGill University involving collaborators from McMaster University, the University of Toronto and other institutions. The team reviewed data from 137 multilingual studies involving 134 cohorts of people around the world. Most studies were from high- or middle-income countries, and about 75% of participants were adults and 25% were children and adolescents aged 10 to 19 years.
To their surprise, the researchers found that despite dramatic stories to the contrary, where changes in mental health symptoms were identified compared to before the pandemic, these changes were minimal for the most part. This was true whether the studies covered the mental health of the population as a whole or that of specific groups (for example, people of particular ages, sex or gender, or with pre-existing medical or mental health conditions).
Summary
Aim
Synthesize mental health outcomes in cohorts before and during the Covid-19 pandemic.
Systematic design review
Data sources Medline, PsycINFO, CINAHL, Embase, Web of Science, China National Knowledge Infrastructure, Wanfang, medRxiv and Open Science Framework Preprints.
Eligibility criteria for study selection Studies comparing general mental health, anxiety symptoms, or depression symptoms assessed on or after January 1, 2020 with results collected from January 1, 2018 to December 31 2019 in any population, and comprising ≥90% of the same participants before and during the Covid-19 pandemic or using statistical methods to account for missing data. Restricted maximum likelihood random effects meta-analyses (worse Covid-19 outcomes representing positive change) were performed. Risk of bias was assessed using a checklist adapted from the Joanna Briggs Institute for Prevalence Studies.
Results
As of April 11, 2022, 94,411 unique titles and abstracts were reviewed, including 137 unique studies from 134 cohorts. Most studies were from high-income (n=105, 77%) or upper-middle-income countries (n=28, 20%).
Among general population studies, no changes were found for general mental health (standardized mean difference (SMD) change 0.11, 95% confidence interval -0.00 to 0.22) or anxiety symptoms (0 .05, -0.04 to 0.13), but depression symptoms worsened minimally (0.12, 0.01 to 0.24).
Among women or female participants, general mental health (0.22, 0.08 to 0.35), anxiety symptoms (0.20, 0.12 to 0.29), and depression symptoms (0.20, 0.12 to 0.29) 22, 0.05 to 0.40) worsened by minimal or small amounts.
In 27 other analyzes across outcome domains among subgroups other than women or female participants, five analyzes suggested that symptoms worsened by minimal or small amounts, and two suggested minimal or small improvements.
No other subgroups experienced changes in all outcome domains. In three studies with data from March to April 2020 and late 2020, symptoms either did not change from pre-Covid-19 levels at both assessments or increased initially and then returned to pre-Covid-19 levels. There was significant heterogeneity and risk of bias between analyses.
Conclusions The high risk of bias in many studies and substantial heterogeneity suggest caution when interpreting the results. However, most symptom change estimates for general mental health, anxiety symptoms, and depression symptoms were close to zero and not statistically significant, and significant changes were of minimal to small magnitudes. There were small negative changes for women or female participants across all domains. The authors will update the results of this systematic review as more evidence accumulates, and the study results will be published online (https://www.depressd.ca/Covid-19-mental-health). |
PROSPERO registration CRD42020179703.
Comments
Women were more affected, but findings do not reflect reports of a widespread mental health crisis, researchers say
Mental health among the general population has not changed much during the Covid-19 pandemic compared to pre-pandemic levels, according to a study published by The BMJ .
Some specific groups, particularly women , appear to have been more negatively affected, but the changes have been minimal to small, researchers say.
Many studies and media reports suggest that Covid-19 has caused widespread deterioration in mental health, but inconsistencies in study quality and misinterpretation of cross-sectional data may have led to misleading results.
To address this, researchers reviewed 137 studies that compared general mental health, anxiety and depression symptoms in populations during the Covid-19 pandemic (from January 1, 2020 or later) with pre-Covid-19 assessments (from January 1, 2018 to December 31, 2019).
Studies had to report data from groups comprising at least 90% of the same participants between the pre-pandemic and pandemic periods or use statistical methods to account for missing data. Most eligible studies were from high- or upper-middle-income countries and were carefully assessed for bias before being included in the analysis.
Differences between groups were expressed as standardized mean differences (SMD). Generally, an SMD of less than 0.2 indicates a minimal effect, 0.2-0.5 a small effect, 0.5-0.8 a moderate effect, and 0.8 or more a large effect.
Among general population studies, no changes were found in general mental health or anxiety symptoms , but depression symptoms worsened minimally (SMD change 0.12).
Among specific groups, women or female participants were the only group to experience worsening symptoms across all outcomes; all because small (SMD changes from 0.20 to 0.22). This is consistent with evidence that women and female members of society have experienced a disproportionately greater burden from the pandemic, the researchers note.
Depression symptoms worsened by minimal or small amounts for older adults, college students, and people who identified themselves as belonging to a sexual or gender minority group, but not for other groups.
Overall mental health and anxiety symptoms have been shown to worsen for parents , although the researchers emphasize that these results were based on a small number of studies and participants.
In contrast, overall mental health and depression symptoms have been shown to improve in people with pre-existing mental health conditions . But again, the researchers emphasize that these results were based on only two studies and the improvement was negligible (SMD change 0.05). No other subgroups experienced significant changes in all outcomes, including youth.
This was a well-designed review based on a comprehensive literature search, but the researchers acknowledge that differences in study design, a high risk of bias in many studies, and a lack of evidence from low-income countries and children may have played a role, and suggest that caution is needed when interpreting their results.
“Across all population groups, the results suggest that, rather than a mental health crisis, at the population level there has been a high level of resilience during Covid-19, and changes in general mental health, symptoms anxiety and depression symptoms have been minimal with no changes detected in most analyses,” they write.
However, they say the pandemic has affected the lives of many people and urge governments to “continue to ensure that mental health supports are available and responsive to the needs of the population.”
While this study clearly shows that we should not be overly concerned about the mental health of the general population in relation to the Covid-19 pandemic, the reported prevalence rates of mental health symptoms, especially among adolescents , remain worryingly high. high, say researchers from Denmark in a linked editorial.
This review does not tell us why any deteriorations occurred, or whether these deteriorations could have occurred even without the pandemic, meaning an underlying pan-social problem, but not related to Covid-19, they write. More research is required to help answer these important questions.
“Pandemic or not, there is a great need to provide preventive mental health interventions for those at highest risk of poor mental health outcomes,” they conclude.
What is already known about this topic?
- A large number of studies and media reports conclude that Covid-19 has caused a widespread decline in the population’s mental health.
- Most existing evidence reviews have relied on cross-sectional studies and conclusions based on proportions of study respondents above thresholds on mental health measures.
- Such methods are not intended to estimate prevalence and can be very misleading.
What this study adds
- Synthesized evidence from 137 studies comparing general mental health, anxiety symptoms, or depression symptoms during the pandemic with pre-Covid-19 outcomes in the same cohort of participants showed no negative changes in mental health at the level of the general population for general mental health or anxiety. symptoms but minimal worsening of depression symptoms.
- Among subgroups, women and female cohorts appear to have experienced worsening overall mental health, anxiety symptoms, and depression symptoms.
- These findings are consistent with evidence that women and female members of society have experienced a disproportionately greater burden from the pandemic.
