Socioeconomic vulnerability and access to community water fluoridation in Washington

Background

The aim of the authors was to determine whether socioeconomic vulnerability is associated with community water fluoridation (CWF).

Methods

The authors used US Census Bureau data to create 4 county-level vulnerability markers (percentages non-White, Hispanic or Latino, below the federal poverty threshold, education below high school), obtained county-level CWF data from the Washington State Department of Health, and evaluated associations using Spearman rank correlation coefficient and the Kruskal-Wallis rank sum test. The authors then interviewed 122 community members in Washington (December 2022-March 2023) and analyzed the interview data inductively.

Results

A higher percentage of non-White people at the county level was associated with a significantly higher level of CWF (Spearman rank correlation coefficient, 0.55; 95% CI, 0.29 to 0.82; P < .001), whereas county-level poverty was associated with significantly lower CWF (Spearman rank correlation coefficient, −0.36; 95% CI, −0.70 to −0.03; P = .02). High school completion was not associated with county-level CWF. Significantly larger proportions of Hispanics and Latinos lived in counties with higher CWF (P < .05). From the interviews, more participants thought tap water was healthy than unhealthy, but 41% had mixed feelings. Similarly, more participants thought CWF was acceptable than unacceptable, with 35% reporting mixed feelings. Negative views about tap water and CWF were more common among non-White participants.

Conclusions

People in racially and ethnically diverse communities in Washington appear to have greater access to CWF, whereas those in lower-income communities have poorer access.

Practical Implications

CWF is an important population-level strategy to prevent caries. Additional work is needed to improve access to CWF, especially for people from low-income communities.