Background
In the past 30 years, nitrite inhalants, including amyl, butyl, and isobutyl nitrites, have become popular as recreational drugs among the homosexual population in developed countries [
1‐
3]. Amyl nitrites have a long history of abuse and are commonly referred to as “poppers.” Butyl and isobutyl nitrites have become attractive substitutes when amyl nitrites are refrained from non-medical use [
4]. Butyl and isobutyl nitrites can be easily obtained in some commercial applications, such as intermediates for perfumes and antifreeze preparations. Butyl and isobutyl nitrites are usually given suggestive trade names, such as “Aroma of Men,” “RUSH,” and “Highball.” These products have been reported to have effects on facilitating and enhancing sexual intercourse and are extensively used by men who have sex with men (MSM) [
1]. Along with the acquired immunodeficiency disease (AIDS) epidemic, studies have shown a correlation between nitrite inhalant use and unsafe sexual behaviors, which lead to human immunodeficiency virus (HIV) infection and increased risk of HIV seroconversion among MSM [
5‐
13].
There are 654,000 people living with HIV (PLHIV) in China and 27.5% of the PLHIV were MSM as of September 2016 [
14]. Injection drug use was the initial route of HIV transmission, but the risk of sharing needles, syringes, or other sources of bloodborne infections has decreased significantly over the past few years because of the national needle exchange program. In a previous study, we found that injection drug use is very rare in the MSM population in China [
15]. Other studies in China in the past few years revealed the prevalence of some new drugs, such as methamphetamine, ketamine, and methylenedioxyamphetamine, instead of opium and heroin [
16,
17]. RUSH use has become popular during recent years. Studies from the United States showed that the prevalence of popper use varied from 25% to 35% since the initiation of highly active antiretroviral therapy [
12,
18‐
21]. A cohort study in Canada found a similar nitrite use ratio, which was 34% in 1995–1996, and remained unchanged in 2002–2004 [
3]. In Japan, a national internet survey of popper use was conducted in 2003. The results showed a very high prevalence of 63.2% [
2]; however, recently, more and more Chinese MSM communities asked us to pay close attention to the use of nitrite inhalants and their potential health effects. A cross-sectional study carried out among HIV-positive MSM in Shanghai in 2010 suggested that the risk of HIV transmission increased three times when RUSH was used in unsafe sexual intercourse [
22]. Another cross-sectional survey conducted among MSM in Beijing in 2012 reported that the HIV prevalence was 9.0% among nitrite inhalants users and 3.3% among non-users [
23]. A recent report from Nanjing showed the increasing trend of RUSH use from 2014 to 2015 among MSM. RUSH use was associated with HIV infection [
24]. Moreover, previous research demonstrated that MSM who had ever used nitrite inhalants had behavior characteristic of preferring sexual pleasure, casual sexual partners, multiple sexual partners, and engaging in risky sexual behaviors [
3,
21,
23,
25,
26]. According to these reports, nitrite inhalants or male perfumes can be easily purchased online in China. Most of the nitrite inhalant users in China are MSM. The aim of our current study was to explore the history and prevalence of nitrite inhalant use and to assess the user’s knowledge and attitude about RUSH among the MSM population in Tianjin, China.
Results
Demographic characteristics
A total of 500 participants were interviewed with informed consent. The age of the participants ranged from 18 to 68 years, with a mean age of 29.7 ± 8.1 years. Of the participants, 98.4% were of Han nationality and 52.2% had a junior college degree or higher. Of the participants, 86.0% were identified as homosexual, 14.0% as bisexual and other. Of all participants, 63.6% resided in Tianjin and 75.2% were single (Table
1). Antibody testing results showed that 38 (7.6%) and 43 (8.7%) participants were HIV seropositive and HSV-2 seropositive, respectively. Fifty-eight (11.6%) participants were infected by syphilis and 40 had symptoms of syphilis (Table
4).
Table 1
Baseline characteristics of study participants (N = 500)
Age (years) |
≤ 20 | 31(6.2) |
21–30 | 306 (61.2) |
31–40 | 107 (21.4) |
41–50 | 40 (8.0) |
> 50 | 16 (3.2) |
Han Ethnic |
No | 8 (1.6) |
Yes | 492 (98.4) |
Years of education |
≤ 12 | 239 (47.8) |
> 12 | 261 (52.2) |
Marital status |
Single | 376 (75.2) |
Married/ divorced/widowed | 124 (24.8) |
Monthly income (RMB) |
≤ 3000 | 390 (78.0) |
> 3000 | 110 (22.0) |
Registered residence |
Not | 182 (36.4) |
Yes | 318 (63.6) |
Occupation |
others | 175 (35.0) |
Students | 53 (10.6) |
Staff in company | 151 (30.2) |
Service | 114 (22.8) |
Live status |
alone | 274 (54.8) |
Only with homosexual partners | 105 (21.0) |
With homosexual or heterosexual partners | 61 (12.2) |
Only with heterosexual partners | 59 (11.8) |
Self-reported sexual orientation |
Bisexual, transgender, or uncertain | 74 (14.0) |
Homosexual | 425 (86.0) |
Knowledge and attitude to RUSH
Among the 500 MSM study participants, 64.0% (320/500) knew that RUSH was an inhaled drug and could be used before or during sexual intercourse. Of the participants, 1.6% (5/320) heard of RUSH for the first time before 2005, 35.0% (112/320) between 2009 and 2010, and 60.0% (192/320) after 2011. The information which participants learned about RUSH came from various MSM activities. The internet was the main source of information for 55.0% (176/320) of participants, homosexual partners for 38.8% (124/320), friends for 36.9% (118/320), MSM-frequented venues (bathhouse, clubs, and bars) for 2.2% (7/320), and MSM parties for 1.6% (5/320). There was one participant who first heard of RUSH from his heterosexual partner. Of the participants, 49.4% had introduced RUSH to their friends or sexual partners. With respect to the attitude of the health effects of RUSH, 55.4% of the participants reported “did not know,” 12.0% reported “definitely had side effects,” 30.6% reported “probably have,” and 2.0% thought RUSH was safe. Of the participants, 45.9% (147/320) reported knowing that RUSH was a corrosive liquid, and 42.2% (134/320) were familiar with the side effects, such as dizziness (37.8%), severe palpitations (30.6%), shortness of breath (15.0%), blurred vision (12.2%), erectile dysfunction (6.6%), confusion (4.4%), tinnitus (4.1%), and vomiting (0.9%). (Table
2).
Table 2
Knowledge and attitude to RUSH among MSM in Tianjin (N = 500)
Knew RUSH |
No | 180 (36.0) |
Yes | 320 (64.0) |
Source of information about RUSH (n = 320) |
Internet | 176 (55.0) |
Homosexual partners | 124 (38.8) |
Friends | 118 (36.9) |
MSM-frequented venues (bathhouse, clubs and bars) | 7 (2.2) |
MSM party | 5 (1.6) |
Heterosexual partner | 1 (0.3) |
Frequency of RUSH use |
Never | 307 (61.4) |
Just one time | 18 (3.6) |
Rarely | 22 (4.4) |
Sometimes | 54 (10.8) |
Often | 55 (11.0) |
Every time | 44 (8.8) |
RUSH did harm to human’ health |
Did not know | 277 (55.4) |
Definitely | 60 (12.0) |
Probably | 153 (30.6) |
Safe | 10 (2.0) |
Symptom of the side effect of RUSH (n = 320) |
Dizziness | 121 (37.8) |
Severe palpitation | 98 (30.6) |
Breath hardness | 48 (15.0) |
Blurred vision | 39 (12.2) |
Erectile dysfunction | 21 (6.6) |
Confusion | 14 (4.4) |
Ttinnitus | 13 (4.1) |
Vomiting | 3 (0.9) |
Status of RUSH use among MSM
In the present study, 193 (38.6%) participants reported that they had used RUSH at least once, and 67.4% (130/193) reported they used RUSH within 1 year. The histories of using RUSH varied from 0.1 to 12.0 years, with a mean history of 1.5 ± 1.1 years. The ages of the participants when first using RUSH varied from 17.1 to 61.6 years, with a mean age of 27.3 ± 7.0 years. Regarding the reasons of using RUSH, increased sexual pleasure accounted for 67.4% (130/193), required by a partner for 63.7% (123/193), pain relief in sexual intercourse for 33.7% (65/193), sexual stimulus for 17.1% (33/193), and drug dependence for 14.0% (27/193). Of the RUSH users, 49.2% (95/193) owned RUSH products, and 69.5% (66/95) of this group of respondents bought RUSH from an online shop, 35.8% (34/95) from friends, 7.4% (7/95) from overseas purchases, and 3.2% (3/95) from adult stores. Among the RUSH users, 22.8% (44/193) used RUSH during every sexual intercourse, 28.5% (55/193) used RUSH often, 28.0% (54/193) used RUSH sometimes, 11.4% (22/193) seldom used RUSH, and 9.3% (18/193) only tried RUSH once. Of the participants, 67.4% (130/193) reported that they had used RUSH to increase voluptus. Simultaneous use of RUSH with other illicit drugs was very rare (only 2 of the participants reported methamphetamine hydrochloride use and 2 declined to report). Of RUSH users, 80.3% reported considering use of condoms when they were using RUSH during sexual encounters, 98 (50.8%) RUSH users had recommended RUSH to his partners or friends, and 92.4% of these introducers thought at least one of their partners or friends began to use RUSH because of their recommendation.
Compared to men who did not report RUSH use, RUSH users were more likely to work in a company (OR: 2.61; 95% CI: 1.65–4.12), live with their homosexual partners (OR: 1.88; 95% CI: 1.19–2.92), live with their homosexual or heterosexual partners (OR: 2.26; 95% CI: 1.29–3.96), be gay (OR: 1.99; 95% CI: 1.14–3.47), smoke (OR: 1.49; 95% CI: 1.02–2.17), use alcohol (OR: 1.63; 95% CI: 1.12–2.39), and seek sexual partners on the internet (OR: 2.59; 95% CI: 1.50–4.50; Tables
3 and
4).
Table 3
Compare of characteristics of study participants, by self-reported use of RUSH (N = 500)
Age (years) |
≤ 20 | 10 (5.2) | 21 (6.8) | 1 |
21–30 | 122 (63.2) | 184 (60.0) | 1.39 (0.63, 3.06) |
31–40 | 47 (24.4) | 60 (19.5) | 1.65 (0.71, 3.83) |
41–50 | 11 (5.7) | 29 (9.5) | 0.80 (0.29, 2.22) |
> 50 | 3 (1.5) | 13 (4.2) | 0.49 (0.11, 2.10) |
Han Ethnic |
No | 4 (2.1) | 4 (1.3) | 1 |
Yes | 189 (97.9) | 303 (98.7) | 0.62 (0.15, 2.52) |
Years of education |
≤ 12 | 88 (45.6) | 151 (49.2) | 1 |
> 12 | 105 (54.4) | 156 (50.8) | 1.16 (0.81, 1.67) |
Marital status |
Single | 159 (82.4) | 217 (70.7) | 1 |
Married/ divorced/widowed | 34 (17.6) | 90 (29.3) | 0.51 (0.33, 0.80) |
Monthly income (RMB) |
≤ 3000 | 146 (75.6) | 244 (79.5) | 1 |
> 3000 | 47 (24.4) | 63 (20.5) | 1.25 (0.82, 1.92) |
Registered residence |
Not | 67 (34.7) | 115 (37.5) | 1 |
Yes | 126 (65.3) | 192 (62.5) | 1.14 (0.78, 1.65) |
Occupation |
others (student, unemployed, retired) | 49 (25.8) | 126 (41.6) | 1 |
Students | 22 (11.6) | 31 (10.2) | 1.82 (0.96, 3.45) |
Staff in company | 76 (40.0) | 75 (24.8) | 2.61 (1.65, 4.12) |
Service | 43 (22.6) | 71 (23.4) | 1.56 (0.94, 2.57) |
Live status |
alone | 94 (49.0) | 180 (58.6) | 1 |
With homosexual partners only | 52 (27.1) | 53 (17.3) | 1.88 (1.19, 2.92) |
With homosexual or heterosexual partners | 33 (17.2) | 28 (9.1) | 2.26 (1.29, 3.96) |
With heterosexual partners only | 13 (6.8) | 46 (15.0) | 0.54 (0.28, 1.05) |
Table 4
Compare of behavior and disease prevalence of study participants, by self-reported use of RUSH (N = 500)
Self-reported sexual orientation |
Bisexual, transgender, or uncertain | 19 (9.9) | 55 (17.9) | 1 |
Homosexual | 173 (90.1) | 252 (82.1) | 1.99 (1.14, 3.47) |
HIV-1 serostatus |
Negative | 181 (94.3) | 281(94.5) | 1 |
Positive | 12 (5.7) | 26 (5.5) | 0.72 (0.35, 1.46) |
History of syphilis |
No | 171 (88.6) | 271 (88.3) | 1 |
Yes | 22 (11.4) | 36 (11.7) | 0.97 (0.55, 1.71) |
HSV-2 serostatus |
Negative | 178 (93.7)) | 273(89.8) | 1 |
Positive | 12 (6.3) | 31 (10.2) | 0.59 (0.30, 1.19) |
Smoking |
No | 115 (59.6) | 211 (68.7) | 1 |
Yes | 78 (40.4) | 96 (31.3) | 1.49 (1.02, 2.17) |
Alcohol use |
No | 116 (60.1) | 219 (71.3) | 1 |
Yes | 77 (39.9) | 88 (28.7) | 1.63 (1.12, 2.39) |
Primary way of seeking sexual partners |
Park, public toilet and othersa
| 19 (9.8) | 63 (20.5) | 1 |
Bars and clubs | 3 (1.6) | 6 (2.0) | 1.66 (0.38, 7.27) |
Bathhouse | 2 (1.0) | 22 (7.2) | 0.30 (0.07, 1.40) |
Internet | 169 (87.6) | 216 (20.3) | 2.59 (1.50, 4.50) |
Discussion
To our knowledge, this is the first study that investigated the knowledge and attitude regarding nitrite inhalant use among the MSM population in China. Most of the participants first heard of RUSH after 2011. Along with its popular use among the MSM population, RUSH has raised new challenges to the health and behaviors of the general public in China. A recent study conducted in Kunming, China reported that there was no significant difference in RUSH use between homosexual and bisexual MSM [
28]. This phenomenon indicated that RUSH use could be expanded to the general population.
Nitrite inhalant use has become very popular among the MSM population in Western countries. The prevalence of nitrite inhalant use was reported to be 36.3%–60% in Europe [
29,
30] and approximately 35.0% in the United States [
9,
16,
31]. Furthermore, The National LGB Drug and Alcohol Database identified that alcohol, poppers, and cannabis were the most commonly used MSM drugs [
31]. In this study, the prevalence of RUSH use in the past 1 year was higher than the prevalence in Western countries, but lower than the prevalence in Asian countries or other parts of China [
2,
3,
23,
32]. The ages of the participants ranged from 18 to 68 years. The mean age was 29.7 ± 8.1 years, which was similar to the previous MSM studies carried out in Beijing, China and in the United States [
23,
31,
33]. The rate of RUSH use in the past 1 year in our survey (26%) was lower than the Beijing MSM study (47.3%) [
23]. The difference in prevalence between the current study and the previous Beijing study may be explained by the differences of economic and cultural environments between the two regions. In comparison, Beijing is a more open and modernized city with a much larger internal migratory population than Tianjin [
23]. According to the 2010 National Population Census data, the itinerant population accounted for 35.9% of permanent residents in Beijing, but only about 25% in Tianjin. The culture and environment is more diverse due to the large number of immigrants. In our study, 63.6% participants resided in Tianjin; however, the percentage was 31.8% in Beijing [
23]. Therefore, the MSM population from Beijing might have more opportunities to communicate with exotic communities than MSM from Tianjin [
34‐
37]. Although the prevalence of RUSH use in Tianjin was lower than other regions of China, the prevalence of RUSH use was still high when compared with data from Western countries [
2,
20,
32,
38,
39].
Our study showed that MSM, who had consumed alcohol, smoked, had better jobs, or lived with homosexual partners and sought partners through the internet, were prone to RUSH use. These findings were consistent with other studies [
10,
33,
40], especially those also carried out in China [
23,
40]. MSM who had the habit of smoking or drinking alcohol might be more inclined to use stimulants. They might have a better job, which could lead to a better income and better access to the substances and substance information [
23]. The characteristics of RUSH users and the source of information about RUSH in this study were also similar to other studies [
2,
33,
40]. In light of these findings, preventive strategies based on our study could be popularized among MSM in China. Studies from the United States suggested nitrite inhalant use increased the risk of HIV or STI infection [
6,
16,
20]. Studies conducted in other cities in China also noted the association of nitrite inhalant use and HIV infection [
22‐
24]. Although we did not find any relationship between RUSH use and HIV infection, there may be regional differences and biases in the convenient sampling methods used in our study.
In the past decades, there have been numerous studies carried out to investigate the relationship between RUSH use and sexual behaviors and/or HIV infection status of the users. However, studies focusing on the level of knowledge of RUSH among MSM are very rare. Our results showed that the MSM population in China knew little about the side effects of RUSH. The lack of knowledge may directly lead to health hazards to the MSM individual users and could even lead to some serious social and public health issues. In light of these concerns, our study will provide some baseline information about the knowledge of and attitude towards recreational drug use among MSM population in China. Health education strategies should be developed to prevent the epidemic of RUSH use and the potential boost of HIV transmission among MSM communities in China. The information of the RUSH distribution channels also indicated that the transaction of RUSH was quite free and active in China.
Nevertheless, several limitations of this study should be kept in mind. First, potential bias about sensitive questions could not be excluded because the questionnaires were interviewer-administered. Second, the participants in our study might not represent the general MSM population due to the potential limitations of enrollment methods. Third, it should be kept in mind that the results of antibody tests might not represent the actual infection status of syphilis infection and the test results might also be influenced by the quality of the samples. Fourth, the cross-sectional study design also has its own limitations on the correlation analysis. Therefore, confirmation of these results is needed by further case-control studies or prospective studies with more sensitive testing methods. Although the data in this study was dated, our findings still gave baseline information on the prevalence of RUSH use and user knowledge among MSM population in Tianjin, China. We consider the surge of its popularity could negatively affect HIV prevention and control. The results of our study should benefit design strategies for appropriate health education.
Acknowledgments
The authors are grateful for the following individuals for their various supports: Lei Gao, Yu Yang, Xiangwei Li, Henan Xin, and volunteers from Tianjin Deep Blue Volunteers Workgroup.