A number of surveys among men who have sex with men (MSM) show associations between inconsistent condom use and use of alcohol and drugs. MSM in six cities in the United States found that higher risk for unprotected sex was associated with heavy alcohol use as well as the use of hallucinogens and stimulants, and especially, amyl nitrates.118 In general, the links between substance use and inconsistent condom use among MSM have been found to be "inconsistent". One cohort study in San Francisco found HIV seroconversion to be associated with higher rates of substance use, including amyl nitrates, amphetamines and cocaine. This general pattern of association between drug use (not alcohol) and HIV positive serostatus has also been found among MSM in Vancouver and in Sydney. Recent research has found that the same pattern exists among ethnic minority MSM in the United States.