Investigation of the increased incidence of gonorrhoea diagnosed in genitourinary medicine clinics in England, 1994-6

Abstract

Objectives: To determine important risk factors associated with cases of gonorrhoea in England, and whether any particular risk groups were associated with the substantial rise in numbers of cases seen between 1994 and 1996.

Design: Two retrospective cross sectional surveys.

Setting: 70 randomly selected genitourinary medicine (GUM) clinics in England.

Subjects: 10% of all gonorrhoea patients attending GUM clinics in England in 1994 (847 patients) and 1996 (1146 patients).

Main outcome measures: For risk factors in 1996 (study 1), unadjusted rates per 100,000 population aged 14-70 and relative rates (RR) with 95% confidence intervals (CIs). For the change in risk factors between 1994 and 1996 (study 2), adjusted odds ratios (ORs) with 95% CIs, derived from logistic regression analyses of data on patients in 1996, with patients in 1994 as the comparison group.

Results: The incidence of gonorrhoea in 1996 was higher in homosexual males (812 per 100,000; RR = 30.2, CI = 25.2 to 36.0) compared with heterosexual males (27 per 100,000); in black Caribbeans (467 per 100,000; 21.4, 17.9 to 25.5) and black Africans (235 per 100,000; 10.8, 7.5 to 15.5) compared with white people (22 per 100,000); and in previous GUM clinic attenders (433 per 100,000; 37.93, 35.46 to 40.56) compared with those who had not attended previously (11 per 100,000). However, most patients were either white or heterosexual. Heterosexual patients in 1996 were significantly more likely to have reduced sensitivity to penicillin (2.55, 1.20 to 5.41) than those in 1994. Male homo/bisexual patients in 1996 were significantly more likely to be from the north west (3.77, 1.45 to 9.80) and to have either reduced sensitivity (2.63, 1.03 to 6.73) or complete resistance (1.98, 1.03 to 3.78) to penicillin, compared with those in 1994.

Conclusions: Homo/bisexual men and the black Caribbean population in England experience a disproportionate burden of gonococcal infections, however, the bulk of diagnoses are in white heterosexuals. No single risk group was associated with the rise in numbers of cases between 1994 and 1996. Resistance to penicillin is widespread and has increased in homo/bisexual men, and it is possible that a rise in treatment failures has, to some extent, enhanced transmission of gonorrhoea and contributed to the rise in numbers of diagnoses in this group.