US dental health care workers’ mental health during the COVID-19 pandemic

related to COVID-19. Dental hygienists were eligible to participate if they were licensed as a dental hygienist in the United States, were at least 18 years old, and were employed as a dental hygienist as of March 1, 2020. The research protocols and surveys were approved by the ADA Institutional Review Board. Potential respondents read and signed an electronic informed consent before responding to the survey. Further details of the study population and questionnaires are described in previous articles.

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to screen respondents for symptoms of depression (using Patient Health Questionnaire-2

) or anxiety symptoms (using Generalized Anxiety Disorder-2

). Scores of 3 or greater on the Patient Health Questionnaire-2 indicate depressive disorder symptoms and have 83% sensitivity and 92% specificity for major depression.

Scores of 3 or greater on Generalized Anxiety Disorder-2 indicate anxiety disorder symptoms, with 86% sensitivity and 83% specificity for generalized anxiety disorder and greater than 50% sensitivity and specificity for panic disorder, social anxiety disorder, posttraumatic stress disorder, or any anxiety disorder.

In both cases, higher scores are indications for further mental health evaluation rather than a definitive diagnosis.

To test whether COVID-19 risk was positively correlated with mental health concerns, we obtained the COVID-19 case rate per 100,000 people in each US state and territory from the Centers for Disease Control and Prevention (CDC) for the 7 days before each survey and categorized the level of community transmission using the CDC’s criteria: low to moderate (

Initial analysis indicated no statistically significant difference in rates of anxiety or depression symptoms between low to moderate or substantial levels of community transmission, so we combined these categories into a single category before defining a regression model. Furthermore, we contrasted the rates of anxiety and depression symptoms in DHCWs who reported at least 1 dose of COVID-19 vaccine with the rates in unvaccinated DHCWs. Vaccination status was added to the survey as of February 1, 2021, so we modeled it separately to avoid constricting the periods of the other regression models.

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As in the general population of US adults, rates of mental health concerns increased in fall and early winter 2020

and then improved in spring 2021.

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rates of anxiety and depression symptoms were lowest in the oldest age groups. As has also been commonly found,

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women reported higher rates of anxiety and depression than men. Unlike a survey of mental health in UK dentists,

we identified no differences in rates of anxiety or depression symptoms among US DHCWs by practice setting (that is, private practice versus public health). This discrepancy may be due to differences in dental health care delivery systems and payers between the UK and United States or may be a reflection of different times of data collection. In results consistent with another report,

we found no significant differences in mental health concerns between DHCWs in general dentistry and those practicing specialties.

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Similarly, in our study, even controlling for other factors related to mental health outcomes such as age and gender, dentists had significantly lower odds of anxiety or depression symptoms than dental hygienists. There are several potential underlying explanations for these differences. Dentists may have felt more in control of infection prevention and control procedures in their primary dental practice, which may have provided a protective buffer against anxiety or work-related stress. In addition, whereas dentists may own their practices, fewer dental hygienists operate independently; most work as employees. Thus, elevated rates of anxiety and depression symptoms among dental hygienists could correlate with concerns of availability of PPE, being unemployed or furloughed,

managing childcare issues, bringing infection home to family members, and properly following national guidance without the control to dictate policies within their primary practice environment.

The narrowing of the gap in anxiety and depression rates between dentists and dental hygienists through May 2021 may indicate that as DHCWs continued to be provided information about national guidance, they were able to deliver care at volumes that approached prepandemic rates, and, as data about low COVID-19 infection rates among DHCWs were reported, their mental health may have been influenced positively. Strategies that enable dental hygienists to be informed, empowered, and included in decision-making processes in dental settings may reduce psychological distress and improve working conditions within the dental team.

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In our study, DHCWs experienced higher rates of anxiety and depression symptoms during high levels of community transmission of COVID-19, and those who wanted to be vaccinated but were not yet vaccinated reported higher levels of anxiety and depression symptoms than those already vaccinated and those not intending to be vaccinated. These findings imply that external factors associated with perceived occupational risks have a significant impact on anxiety and depression symptom rates among DHCWs. Ensuring DHCWs have the resources necessary to safely practice dentistry, including PPE, vaccination, and adherence to CDC guidance, may reduce psychological distress. The ADA and American Dental Hygienists’ Association have expanded resources available to support dentists’ and dental hygienists’ mental and emotional health.

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or social desirability bias against reporting mental health concerns that affects 1 professional group disproportionately. Unmeasured factors such as overall household income and expenses, financial difficulties, known stressors (for example, childcare or eldercare) during the pandemic, or level of patient contact also may influence mental health and account for the measured differences between dentists and dental hygienists. Furthermore, the PHQ-4 is meant for mental health screening, not diagnosis, and thus the results of our study do not reflect prevalence of definitive mental health diagnoses. Conversely, there are also strengths to this research. The sample of dentists is broadly similar to US dentists on all measured variables. How representative the surveyed dental hygienists are of dental hygienists nationally is unknown, but those surveyed do represent every level of experience, type of dental practice, measured demographic characteristic, and US state. To our knowledge, it is the first, and perhaps only, study evaluating mental health in a cohort of DHCWs over the course of the COVID-19 pandemic and shows distinct differences between dentists and dental hygienists that could be used to tailor communication strategies to each group as well as inform mental health screening and support. Our study is uniquely suited to identify points in time at which anxiety and depression particularly troubled DHCWs and align such increased rates of adverse mental health outcomes with local COVID-19 transmission rates. This is also the first study, to our knowledge, to evaluate the association between COVID-19 vaccination and US DHCW mental health and highlight the potential psychological impact of vaccination on the overall well-being of DHCWs. These findings highlight the importance of monitoring mental health in DHCWs and suggest areas for future research, such as investigating the incidence of trauma, self-harm, and related disorders or exploring why certain demographic or practice groups experienced high rates of anxiety and depression over time.