Table 2.

Association between rural residence and suboptimal antibiotic use.

Suboptimal Antibiotic Use	Rural-Residing Veterans (n = 937,007)	Urban-Residing Veterans (n = 3,002,794)	Unadjusted Odds Ratio (95% Confidence Interval)	Adjusted Odds Ratio (95% Confidence Interval)
Fluoroquinolone exposure a	60,890 (19.0%)	190,019 (17.5%)	1.11 (1.10–1.12)	1.03 (1.02–1.04)
Longer antibiotic course *,b	172,433 (53.8%)	526,423 (48.5%)	1.24 (1.23–1.25)	1.19 (1.18–1.20)

The data are n (%) or adjusted odds ratio (95% confidence interval). Bold indicates the p-value < 0.05 for comparison of the rural and nonrural residence. The adjusted odds ratios were estimated from generalized linear mixed models with a binary distribution and logit link, accounting for clustering by region and year. * Longer antibiotic courses were defined as prescriptions with durations of ten days or greater. ^a Adjusted for age, infection diagnosis, cerebrovascular disease, chronic pulmonary disease, depression, hypertension, liver disease, peripheral vascular disease, malignancy, Charlson comorbidity score higher than the median, sex, race, region, and year. ^b Adjusted for age, infection diagnosis, atherosclerosis, alcohol disorder, cerebrovascular disease, Elixhauser score higher than the median, depression, hypertension, liver disease, myocardial infarction, obesity, malignancy, Hispanic ethnicity, marital status, sex, race, region, and year.