Discussion
Spina bifida disproportionately impacts Hispanic Americans.38 39 The overall prevalence of spina bifida in Hispanic Americans was reported to be 3.80 per 10 000 births of spina bifida in Hispanic Americans (CI 3.6, 4.0) from 1997 to 2007.7 The majority of papers reported a higher prevalence in Hispanic Americans compared with NHW, which remains higher than predicted after mandatory and voluntary folate fortification initiatives. Birth prevalence of spina bifida in Hispanic Americans did decrease following fortification but continued to remain higher than NHW. This suggests either ineffective fortification measures, Hispanic American-specific risk factors or a combination of both.11
The most common risk factors identified were poor socioeconomic status (SES), immigration, toxic exposures and clinical factors. Poor SES stands as one established risk factor for spina bifida primarily in connection to limited access and affordability of healthcare as well as prenatal and preconceptual care.40 41 Low educational attainment, maternal age and income status were commonly reported. On average, 45.2% of Hispanic American mothers included in this review obtained less than a high school diploma compared with 8.9% of the US population in 2021.42 The average maternal age at first birth for the general US population in 2021 was 27.3 years old compared with 25.5 years for Hispanic American women.43 However, in our review, 45.5% of mothers were younger than 25 years old. Hispanic Americans are disproportionately represented among the impoverished demographic; in 2017, individuals of Hispanic descent constituted 18.3% of the overall American population, yet accounted for 27.2% of the population residing in poverty.44 Chronic conditions, such as spina bifida, increase the risk of poverty. Approximately 40.2% of HSB families report an annual income of less than $10 000.18 Low SES communities often have a high percentage of immigrants who are well-known to face healthcare disparities due to language barriers, low health literacy, limited access to care and fear of seeking healthcare.45 These communities face higher exposure to air pollutants and other environmental hazards. In addition, these communities are more likely to live in food deserts or experience food insecurity, increasing the risk of vitamin deficiencies, obesity and diabetes mellitus type 2.18 44 46 47
Low SES not only heightens the risk of having an infant with spina bifida, but also exacerbates the burden associated with managing this condition.48 The estimated lifetime cost of care for spina bifida is $791 900 including $214 900 in caregiving costs.49 Therefore, the financial costs of spina bifida care are particularly formidable for low SES families.18 Hispanic Americans also face an increased likelihood of experiencing challenges in affording essential caregiving services, as the most frequent race/ethnicity without health insurance coverage.50 In 2020, 18.3% of Hispanic Americans were uninsured compared with 5.4% of NHW. Insurance status, whether uninsured or underinsured, may significantly impact these families’ quality of care. Children with spina bifida report reduced quality of life compared with their same-aged peers.51 This is exacerbated in Hispanic Americans in both direct and indirect HRQoL measures.3 19 32–37
Despite this increased risk and morbidity, Hispanic Americans are under-represented in research including studies of both prevention and treatment initiatives. In the landmark randomised control trial, the Management of Myelomeningocele Study (MOMS), Hispanic Americans only accounted for 3.8% of the study population. The MOMS established that prenatal repair demonstrates improved functional outcomes and reduced morbidity compared with postnatal repair.52 We found low prenatal repair rates in Hispanic Americans which could be explained by their low likelihood to qualify for fetal surgery through insurance.36 37 Additional factors that may influence the decision to undergo prenatal repair include cost of travel to treatment centres, eligibility for the procedure and cultural factors. Among participants without insurance, 83.3% reported the cost of travel to the centre or hospital as a significant financial factor influencing their decision.53 Furthermore, obesity may be a disqualifying factor; body mass index >35 was an exclusion criterion for the MOMS and obesity was significantly associated with mothers of HSB.25 47 Lack of cultural competency and language differences were commonly cited as barriers to undergoing prenatal surgery.54 The role of low rates of birth termination among Hispanic Americans due to religious, cultural and health access issues should be considered as a possible influence on the overall disease incidence and prevalence.
The impact of spina bifida manifests itself as a self-perpetuating cycle influenced by low SES. Hispanic Americans face an elevated risk of having an infant with spina bifida secondary to a multitude of preconception and post-conception risk factors discussed above. These risk factors can influence the access to services and procedures, such as fetal repair, which have the greatest potential to improve lifetime morbidity.7 36 37 Diminished ability to afford essential caregiving services, as well as physical and occupational therapy, further amplifies the morbidity associated with this condition.50
There are multiple limitations to this study. There is a lack of standardised measures for risk factors, morbidity and prevalence. Studies also varied in size, time period and region which significantly impacts prevalence rates and demographic factors. Many studies had small sample sizes. Hispanic Americans continue to be under-represented in participation. The role of prenatal care and deficiencies in access to care are poorly measured critical determinants. Health literacy is also an important topic lacking data to support context-specific interventions. Additional research to improve standards in reproductive health is imperative. We recognise that many risk factors in this study influence the prevalence and morbidity of spina bifida in Hispanic Americans. Further research is needed to understand the impact of these risk factors on influencing the epidemiology and patient-related outcomes among Hispanic American mothers and their children.
Future directions
Many of the risk factors identified in this review are well-known mediators impacting health outcomes among Hispanic Americans (ie, SES, toxic exposures, immigration status and diabetes mellitus). The best interventions would target population-specific factors that uniquely contribute to increased disease prevalence and poor patient outcomes. Investigating the role of religion and cultural beliefs in spina bifida prevalence and treatment choices could help address the disparities in prevention of spina bifida and access to effective treatment when new births are diagnosed. Interventions to aid in improved preconceptual and prenatal access as well as education among reproductively active Hispanic Americans are crucial. Providers should be cognisant of health literacy in patients given low levels of educational attainment seen in mothers of HSB; educational campaigns may need to be adjusted for health literacy differences. Furthermore, it is pivotal to identify safer and more effective routes of passive folic acid supplementation, such as additional stable grain products or fortified salt.55–57 These efforts can be further integrated into existing regional and national policies. It is difficult to eliminate the role of toxic exposures as this is strongly linked with economic livelihood of many families. Providing education and awareness among high-risk populations could be a reasonable approach to initiate larger interventions.