Syringe services programs in the Bluegrass: Evidence of population health benefits using Kentucky Medicaid data.

Purpose: To evaluate whether Kentucky counties that established a new syringe services program realized a significant decline in the incidence rate of a set of infectious disease diagnoses commonly transmitted via injection drug use.

Methods: Longitudinal count models of within-county rates of newly diagnosed infections among populations at risk were estimated using Medicaid claims/encounters data. Generalized estimating equation models were used to report incident rate ratios of 6 diagnoses: (1) HIV; (2) hepatitis C; (3) hepatitis B; (4) osteomyelitis; (5) endocarditis; and (6) skin/soft tissue infection. To investigate whether a delay in effect was present, separate models were fit to estimate the effects of establishing a syringe services program: at its opening date, and again at 1, 3, and 6 months postopening date.

Findings: Taken together, the aggregated within-county incidence rate of these 6 diagnoses was significantly lower following the implementation of a syringe services program (P < .05). Our models estimated that counties which opted to open a syringe services program realized an approximate month-over-month decline in new diagnoses of 0.5% among the population at risk.

Conclusions: These results lend further support to previous conclusions made in the public health literature regarding the efficacy of syringe services programs. Specifically, declines in incidence rates were observable beginning at 1 month post syringe services program opening. These results are particularly notable due to the typical setting in which these syringe services programs operated-rural communities of fewer than 40,000 residents.