Background/introduction Surveillance data show high rates of bacterial STIs among people of black and mixed ethnicity and those living in deprived areas.

Aim(s)/objectives To determine whether variations in bacterial STI diagnosis rates across ethnic groups are accounted for by socio-economic deprivation (SED).

Methods Data on STI diagnoses made in genitourinary medicine (GUM) clinics in England in 2013 were obtained through the GUM Clinic Activity Dataset-v2. SED was derived using the Index of Multiple Deprivation (IMD), a measure of area-level deprivation for each Lower Super Output Area of residence. Incidence rate ratios (IRRs) for each STI were derived using Poisson regression, adjusting for IMD.

Results Black Caribbeans and those of ‘black other’ ethnicity had the highest crude rates (per 100,000 population) of chlamydia (812.5 and 629.8), gonorrhoea (291.0 and 208.0) and syphilis (43.8 and 35.0), respectively, while rates in those of ‘white British’ ethnicity were 151.1, 36.3, and 5.0, respectively. Relative to ‘white British’, unadjusted IRRs [95% CI] for black Caribbean and ‘black other’ ethnicity were 10.67 [9.34–12.19] and 9.91 [8.01–12.25] for syphilis, 8.18 [7.77–8.61] and 5.76 [5.28–6.29] for gonorrhoea and 6.18 [5.99–6.37] and 5.61 [5.34–5.90] for chlamydia. After adjustment for IMD, IRRs decreased to 7.62 [6.65–8.72] and 7.26 [6.17–8.55] for syphilis, 5.77 [5.48–6.08] and 3.92 [3.60–4.28] for gonorrhoea and 4.97 [4.82–5.12] and 4.38 [4.17–4.61] for chlamydia.

Discussion/conclusion SED only partially explains the disparity in STI diagnoses rates observed across ethnic groups. The role of sexual behaviour, attitudes to risk and contextual factors should be explored to inform development of appropriate interventions.