COVID-19 Vaccination Intentions for Children with Medical Complexity

Abstract

Objectives:

The chronic conditions and functional limitations experienced by children with medical complexity (CMC) place them at disproportionate risk for COVID-19 transmission and poor outcomes. To promote robust vaccination uptake, specific constructs associated with vaccine hesitancy must be understood. Our objective was to describe demographic, clinical, and vaccine perception variables associated with CMC parents’ intention to vaccinate their child against COVID-19.

Methods:

We conducted a cross-sectional survey (June - August 2021) for primary caregivers of CMC between ages 5-17 at an academic medical center in the Midwest. Multivariable logistic regression examined associations between vaccination intent and selected covariates.

Results:

Among n=1,330 families, 65.8% indicated vaccination intent. In multivariable models, demographics had minimal associations with vaccination intent; however, parents of younger children (<12 years) had significantly lower adjusted odds of vaccination intent (aOR [95% CI]: 0.26 [0.17-0.3]) compared to parents of older children (≥12 years). CMC with higher severity of illness, i.e., those with ≥1 hospitalization in the prior year (vs none) or >1 complex chronic condition (vs 1), had higher adjusted odds of vaccination intent (1.82 [1.14-2.92] and 1.77 [1.16-2.71], respectively). Vaccine perceptions associated with vaccine intention included “My doctor told me to get my child a COVID-19 vaccine” (2.82 [1.74-4.55]); and “I’m concerned about my child’s side effects from the vaccine” (0.18 [0.12-0.26]).

Conclusions:

One-third of CMC families expressed vaccine hesitation; however, constructs strongly associated with vaccination intent are potentially modifiable. Pediatrician endorsement of COVID-19 vaccination and careful counseling on side effects might be promising strategies to encourage uptake.

INTRODUCTION

Chronic conditions, functional limitations, and family-identified service needs are defining features experienced by children with medical complexity (CMC), and simultaneously drive disproportionate COVID-19 burden.^{1, 2} Compared to children without medical complexity, CMC have almost 8 times higher odds of hospitalization for COVID-19 and 3 times higher odds of severe illness once hospitalized.³

Although COVID-19 vaccination has been associated with reduced morbidity and mortality, vaccine hesitancy exists.⁴ Parents of CMC, a group with sophisticated medical knowledge and expertise about their child’s unique conditions,⁵ may have distinct vaccine concerns as compared to general populations. Since limited vaccine hesitancy data exist among caregivers for CMC, understanding vaccine perceptions is a necessary step to promote uptake. The objective of this study was to describe demographic, clinical, and vaccine perception variables associated with CMC parents’ intention to vaccinate their child against COVID-19.

METHODS

This cross-sectional survey was conducted from June-August 2021 at an academic medical center in the Midwest, as a part of the NIH’s Rapid Acceleration of Diagnostics-Underserved Populations (RADx-UP) Return to School initiative. CMC were defined as children ages 5-17 years with at least two encounters at our medical center in 2020 and at least one Complex Chronic Condition (CCC), defined as any medical condition expected to last at least 12 months and involve one or more different organ systems severely enough to require specialty care and likely hospitalization at a tertiary care center.⁶ All self-identified English- or Spanish-speaking primary caregivers of CMC attending school before March 2020 with an address available in the electronic medical record were eligible. The survey instrument was comprised of items from the NIH’s RADx-UP Common Data Elements library, which included standardized questions about COVID-19 vaccination acceptance in addition to demographics and health history.⁷ The mail survey was administered by the university’s survey center. Eligible participants received a $5 pre-incentive with each mailing and a $50 completion incentive. Up to three attempts were made to reach participants.

The binary outcome “vaccination intent” was defined as either (1) responding “very likely” to the question, “How likely is your child to get an approved COVID-19 vaccine when it becomes available?”, or (2) reporting receipt of at least one COVID-19 vaccine dose for their child. At the time of the survey, COVID-19 vaccines were authorized only for those 12 years of age and above. Predictor variables included demographics, health status, and vaccine perceptions. As prior studies have underscored racial and ethnic disparities in morbidity and mortality from COVID-19 and in COVID-19 vaccine acceptance, we included this variable in our analyses.^8,9 Additional demographic variables included age (caregiver and child), gender (child), household income, highest education level, and insurance (public, private, none). Health status variables included caregiver vaccination status, number of CCCs (1 vs >1), hospitalizations in the prior year (0 vs 1 or more), and expected severity of COVID-19. In addition to vaccination intent, questions regarding vaccine perceptions from the RADx-UP Common Data Elements library describe reasons caregivers would or would not vaccinate their child (“Which of the following would be reasons you would vaccinate your child?”).

Bivariate followed by multivariable logistic regression models estimated associations between vaccination intent and covariates. Covariates with statistically significant bivariate associations with vaccination intent were included in the multivariable model: child’s age, number of hospital encounters, insurance type, and vaccine perceptions. Additionally, a priori selected variables informed by prior literature⁴ were included: household income, race and ethnicity, highest education level, number of CCCs, and expected severity of COVID-19. Parental vaccination status was considered as a covariate due to its high correlation with vaccination intent, but was ultimately removed from the model due to concern for collinearity.

Further analysis used Chi-squared tests to assess differences of respondents and non-respondents, using available data from the eligible cohort creation. Analyses were conducted in SASv.9.4. P-values <0.05 were considered statistically significant. Consent was obtained by mail and the study was approved by the university’s institutional review board.

RESULTS

Of 2,977 eligible families, 1,330 responded (44.7%). Respondent and child characteristics are summarized in Table 1. Caregivers were median (interquartile range, IQR) 43 (39 - 48) years old with varied education and income levels. 61% of caregivers had private insurance for their child, while 37% had either private and public insurance, or public insurance only. Within CMC, 29% had 2 or more CCCs and 18% had 1 or more hospital admissions in 2020. Responders and non-responders had similar clinical characteristics, though a higher proportion of non-responders identified as being from one of the following groups: Hispanic or Latino, non-Hispanic Black or African-American, non-Hispanic multiracial, or of another race. (Appendix).

Table 1:

Respondent and Child Demographic Characteristics, n = 1329

	n (%)
Caregiver Characteristics
Age
Median (IQR)	43 (39 – 48)
Parent Race/ Ethnicity
White, Non- Hispanic	1090 (82.0)
Hispanic	96 (7.2)
Black, Non- Hispanic	53 (4.0)
Other Race/ Ethnicity, Non- Hispanic	60 (4.5)
Multiracial, Non- Hispanic	30 (2.3)
Primary Language
English	1210 (91.0)
Spanish	75 (5.6)
Other	44 (3.3)
Highest Education
Less Than 12th Grade	27 (2.0)
GED/ Some College	486 (36.8)
Bachelor’s Degree	451 (34.2)
Advanced Degree	355 (27.0)
Income
Less than $40,000	160 (12.0)
$40,000 - $74,999	275 (20.7)
$75,000 - $99,999	190 (14.3)
More than $100,000	562 (42.3)
Not reported	142 (10.7)
Parental COVID-19 Vaccination Status
Yes	1083 (81.5)
No	246 (18.5)
Primary Insurance Type
Public Insurance	492 (37.0)
Private Insurance	815 (61.3)
Other Insurance	22 (1.7)
Child Characteristics
Sex
Male	691 (52.3)
Female	631 (47.7)
Age
5 – 10 Years old	513 (38.8)
11 – 13 Years old	304 (23.0)
14 – 17 Years old	506 (38.2)
Number of Complex Chronic Conditions (CCCs)
1 CCC	941 (70.8)
2 or More CCCs	388 (29.2)
Hospital Admissions in 2020
0 Hospital Admissions	1090 (82.0)
1 or More Hospital Admissions	239 (18.0)

Note: Numbers and percentages in this table reflect non-missing values. Caregivers with both private and public health insurance are included within the category of public health insurance.

Two-thirds of respondents (n=875) indicated vaccination intent. In the multivariable analysis (Figure 1), demographic variables had few associations with vaccination intent; however, parents of younger children (<12 years) had significantly lower adjusted odds of vaccination intent (aOR [95% CI]: 0.26 [0.18 - 0.38]) compared to parents of children ≥12 years. CMC with a higher severity of illness, i.e., those with ≥1 hospitalization (vs none) or >1 CCC (vs 1), had higher adjusted odds of vaccination intent (1.75 [1.09 - 2.81] and 1.74 [1.13 - 2.67], respectively).

Figure 1:

Adjusted odds ratios (ORs) of a multivariate logistic regression: all listed covariates on parent COVID-19 vaccination intent for CMC (n = 1313). The vaccination intent column refers to the vaccination intent within the row’s specified group. Model variables include child’s age, number of hospital encounters, insurance type, and vaccine perceptions, household income, race and ethnicity, highest education level, number of CCCs, and expected severity of COVID-19.

Vaccine perceptions with the largest effect sizes on vaccination intent were “My doctor told me to get my child a COVID-19 vaccine” and “I’m concerned about my child’s side effects from the vaccine” (2.97 [1.82 - 4.83] and 0.18 [0.12 - 0.27], respectively). Associations between vaccine perceptions and vaccination intent can be found in Figure 1.

DISCUSSION

In this cross-sectional survey, only two-thirds of CMC parents indicated COVID-19 vaccination intent. While this might be a higher proportion than general pediatric populations,⁴ the unique vulnerability of CMC highlights the need for further action. Our findings suggest that parental vaccination intent revolves broadly around child safety concerns and personal risk assessment. These perceptions associated with COVID-19 vaccination intent from this regional cohort represent several clinical and policy targets to promote acceptance.

First, as observed in other pediatric vaccine hesitancy studies with general populations not limited to CMC,^{4, 10} physician recommendation greatly correlates with acceptance. General and subspecialty pediatricians have an opportunity to listen carefully to concerns, provide trusted sources of information, and encourage vaccination. Addressing safety concerns is of paramount importance. From clinical practice, we know that concerns differ greatly from one family to another, e.g., some fear fevers could precipitate metabolic crisis or seizures, or that myocarditis may complicate pre-existing cardiovascular disease. Others fear complications stemming from concerns about insufficient CMC inclusion in vaccine safety and efficacy trials.

Although physicians should share evidence-informed safety messaging for all families, caregivers of CMC may have more nuanced information needs. For example, clinicians can highlight that, in the phase 2-3 safety and efficacy studies of the BNT162b2 vaccine (commonly referred to as the “Pfizer vaccine”) among 5-11 year olds, 20% of the participating children had co-existing conditions, including conditions commonly faced by CMC.¹¹ The American Academy of Pediatrics, the Centers for Disease Control and Prevention, and the Children’s Hospitals’ Association provide additional useful resources.^12,13,14 Finally, since parents of children ages 5-12 years were the least likely to have vaccination intent (52.3%), specific attention must be directed to this population.

Limitations include unknown generalizability beyond the Midwest, survey responses under-representing non-white, Hispanic, or commercially insured participants, and the likelihood that COVID-19 vaccine perceptions will change with time and with authorization to younger ages. While under-representation of non-white racial and ethnic groups may have affected our results, the direction of bias is unclear. For example, recent papers note differences in vaccination intent, with Non-Hispanic Asian and Hispanic/ Latino populations reporting the highest intent to vaccinate; however, these differences may no longer be significant in adjusted models.^{4, 15}

This study is among the first to quantify vaccine intentions among CMC, noting that constructs associated with hesitancy are potentially modifiable. Pediatrician endorsement of COVID-19 vaccination and careful counseling on side effects might be promising strategies to increase uptake. Additional research on vaccine uptake for this high-risk population is needed.

Abbreviations:

CMC

Children with medical complexity

CCC

Complex Chronic Condition

CDC

Centers for Disease Control and Prevention

AAP

American Academy of Pediatrics