Early syphilis. Relationship to sex, drugs, and changes in high-risk behavior from 1987-1990.

A case-control study was conducted to evaluate two main questions: 1) which specific sex- and drug-use behaviors are associated with the acquisition of early syphilis; and 2) whether changes in sex- and drug-use behaviors from 1987-1990 associated with acquisition of early syphilis. Risk factors associated with significant odds ratio were greater than four sex partners and lack of condom use in the past 3 months. Crack use within the past 3 months was the only specific drug-related risk factor with a significantly elevated odds ratio. However, a number of risk factors associated with both sex and drugs had significantly elevated odds ratios: number of drug-using partners, number of partners exchanging sex for drugs and money, and number of partners with whom the respondent shares sex and drugs. Risk estimates for early syphilis were uniformly higher for women as compared with men. Women appeared to be at higher risk of syphilis than men when engaged in the same high-risk activities. From 1987-1990, there was a significant change from lower-risk to higher-risk behaviors among patients. Patients showed an increase in their number of sex partners, in drug use, and in other high-risk activities. Increasing rates of syphilis can be attributed to a particular set of sex- and drug-related behaviors, and an increase in the adoption of these behaviors has probably contributed significantly to the increased rate of early syphilis in Trenton, NJ, during the period from 1987-1990.