Underinsurance as a Persistent Driver of Cross-Border Antibiotic Procurement in US Border Communities

In the area surrounding the nearly 2000 miles of the border along the United States and Mexico, cross-border health care has long been an option that US border residents, especially those who are underinsured, use to fill the gaps left by their American health care. A recent study published in Frontiers in Public Health aimed to provide insight into the social, cultural, and clinical influences on the practice, focusing on antibiotics specifically.

The US border is a known area of opportunity when it comes to health care access, and residents along the border are generally of lower socioeconomic means than the overall populations of their respective states.

“Financial barriers, including the absence of health insurance and high out-of-pocket costs, impede easy access to health care and prescription drugs in the U.S. and incentivize individuals in border communities to capitalize on the less expensive and more accessible alternatives in Mexico,” study authors wrote.

Using medications without prescription or those that are prescribed to others is a particularly concerning informal health care practice, especially with medications like antibiotics that are associated with antimicrobial resistance when misused. Antibiotics have also been one of the biggest drivers of cross-border care access, although many of the studies that determined this were done before 2010, when many medications that required a prescription in the United States could be bought over the counter in Mexico.

The current study collected data during baseline examinations for the Diabetes Prevention and Microbiome study, an ongoing cohort started in 2017 to assess the relationship between the gut microbiome and type 2 diabetes development in Mexican American adults living in Starr County, Texas. Starr County, which is among the most impoverished counties in the country, is one of the 14 Texas counties on the US-Mexico border.

To identify the forces driving cross-border antibiotic acquisition, 616 adults in the cohort, 52.60% of whom were uninsured and 24.03% of whom were unemployed, were asked about antibiotic use and preferences.

A total of 275 participants (44.48%) reported taking any antibiotics within the past 12 months, and 174 (63.5%) of those participants preferred to source them from Mexico. There were a total of 455 rounds of antibiotics used. A total of 65 participants took at least one antibiotic in the 30 days prior to their exam, and 72.31% of them sourced their most recent course from Mexico. Most of the antibiotic courses used were penicillin-class (51.87%), and almost 80% of penicillin-class drugs were sources in Mexico.

Women were more likely than men to have used antibiotics in the past year (48.9% vs 33.3%, respectively), and there were no significant differences in overall antibiotic use related to household income, insurance employment, marital status, or acculturation measures.

Health insurance status was a major influence on cross-border health care use in this cohort, with univariate logistic regression showing that uninsured participants were 3.36 times more likely to procure antibiotics in Mexico compared with insured participants. A statistically insignificant association was seen between likelihood to cross the border for antibiotics and part-time or unemployment. Household income, marital status, and education were not associated with antibiotic source preference.

In a multivariable logistic regression, uninsured patients were 3.31 times as likely to procure antibiotics in Mexico after adjusting for generation score (to measure acculturation) and the rounds of antibiotics used. A previous National Health Interview Survey saw a very similar trend in uninsured patients, with the uninsured 3.14 times as likely to seek prescription medication outside the U.S. compared with insured respondents.

Overall, the most predictive factors in this cohort were a lack of insurance and participants’ level of acculturation. The findings suggest that despite the changes in Mexican policy that altered prescription regulations in 2010, some of the factors that have long influenced cross-border health care acquisition, particularly antibiotics, are still present today.

“The preference for Mexican antibiotics in our underinsured, low-income study cohort suggested that more affordable antibiotics across the border may provide an avenue for obtaining prescription drugs for those for whom care might otherwise be unaffordable in the U.S.,” study authors wrote.

Notably, changes in immigration and the Affordable Care Act are projected to increase the number of uninsured Texans over time, meaning a lack of insurance will likely continue to drive cross-border health care.

Facilitating antibiotic stewardship programs is one way to help mitigate the issue of overuse or inappropriate use, and hospitals have been implementing such programs. But community-based programs to educate the public on the importance of proper antibiotic use have not yet been established.

“These results may be used to inform future public health initiatives to provide culturally sensitive education about responsible antibiotic stewardship and to address barriers to U.S. health care and pharmaceutical access in medically underserved, impoverished U.S.-Mexico border communities,” the authors concluded.

Reference

Essigmann HT, Aguilar DA, Perkison WB, et al. Epidemiology of antibiotic use and drivers of cross-border procurement in a Mexican American border community. Front Public Health. Published online March 10, 2022. doi:10.3389/fpubh.2022.832266