Incidence of gonorrhoea diagnosed in GUM clinics in South Thames (West) region

Objectives: To describe the incidence of gonorrhoea diagnosed in genitourin ary medicine (GUM) clinics in South Thames (West) between 1995 and 1996, an d how it changed among population subgroups. Settings and subjects: Cases of uncomplicated and complicated gonorrhoea di agnosed at 13 GUM clinics in the former South Thames West (STW) Regional He alth Authority that reported disaggregate data to the South Thames GUM Clin ic Collaborative STD Surveillance Scheme. Methods: Annual incidence rates (per 100 000) of gonorrhoea diagnoses by se x, age group, ethnic group, area of residence, and year were calculated. Po isson regression models were used to calculate risk ratios (RR) to describe the key differences in the variation of gonorrhoea cases by these variable s. Relative differences in the incidence of diagnosed gonorrhoea between 19 95 and 1996 were investigated by including an interaction between year and the other variables (age group, sex, ethnic group, region) and testing whet her any were significant using a likelihood ratio test. Results: Area of residence, sex, age group, and ethnic group were key predi ctors of the rates of diagnosed gonorrhoea. The risk ratio for gonorrhoea ( after adjustment for the other variables) was: 13 times higher among blacks than the white population; twice as high in inner London compared with out er London; and three times lower in the "shire" region compared with outer London. The rate of diagnosed gonorrhoea was significantly higher in the bl ack population in the shire region than the inner London white population. The rate of gonorrhoea diagnosed by GUM clinics from 1995 to 1996 almost do ubled in the white population aged 15-44 years, from 16 cases per 100 000 t o 30 cases per 100 000 (adjusted RR 2.0, 95% CI 1.6 to 2.4), whereas increa sed rates in the black and Asian/other ethnic groups were not statistically significant (adjusted RR 1.1, 95% CI 0.9 to 1.4; and 1.4, 95% CI 0.7 to 2. 7 respectively). Conclusion: The observed increase in gonorrhoea between 1995 and 1996 occur red mostly among heterosexual white men and women, Overall, the rates of go norrhoea among young people, especially in the black population and in inne r London represent a significant public health problem that may merit furth er targeted interventions, the effectiveness of which could be monitored th rough further development of routine surveillance data.