Aims: To determine relationships between drug use "hardness" (defined in increasing order of hardness as no drug use, marijuana use, non-injected heroin or cocaine use, crack smoking and injection drug use) and prevalences of several sexually transmissible infections among young adults in a high-risk neighbourhood. Drug users, particularly injection drug users and crack smokers, may be a core group for some sexually transmitted infections.
Design: Cross-sectional survey and assays of young adults from (a) a household probability sample and (b) a targeted sample of youth who have used injected drugs, crack, other cocaine or heroin.
Setting: Bushwick, an impoverished New York City minority neighbourhood with major drug markets.
Participants: A total of 363 18-24-year-olds from a household probability sample; 165 Bushwick 18-24-year-olds who have used injected drugs, crack, other cocaine or heroin.
Measurements: Drug use by self-report; serum- and urine-based assays for HIV, hepatitis B and C, syphilis, gonorrhoea, chlamydia and herpes simplex (type 2).
Findings: Household-sample prevalences: HIV, hepatitis C and syphilis, 1%; gonorrhoea 3%; chlamydia 5%; past or present hepatitis B infection 8%; herpes simplex (type 2) 18%. In combined household and targeted samples, hepatitis C and HIV were concentrated among drug injectors. Herpes simplex (type 2), syphilis and hepatitis B increased among women with "hardest drug ever used".
Conclusions: Using "harder" drugs is associated with some but not all of these infections. Prevention efforts should help youth avoid unsafe sex and higher-risk drugs.