Anal cancer screening knowledge, attitudes, and experiences among men who have sex with men in Ottawa, Ontario.
KEY WORDS: Anal cancer, screening, men who have sex with men (MSM), HPV vaccine
Anal cancer is a relatively rare cancer; age-standardized incidence rates are estimated to be between 1 to 2 per 100,000 (Grulich et al., 2012). Certain groups, however, are disproportionately affected compared to the general population. At highest risk are both HIV-positive and HIV-negative men who have sex with men (MSM) (Daling et al, 2004; Darragh & Winkler, 2011). MSM are estimated to be 17 times more likely to develop anal cancer compared to heterosexual men (Daling et al., 2004). Annual estimates of incidence range from 5.1 (Machalek et al., 2012) to 36.9/100,000 (Daling et al., 1982) among HIV-negative MSM, and from 45.9 (Machalek et al., 2012) to 224/100,000 (Diamond, Taylor, Aboumrad, Bringman, & Anton-Culver, 2005) among HIV-positive MSM. By comparison, North American estimates of cervical cancer incidence among women before screening ranged from 17.7 to 38.0/100,000 (Gustafsson, Ponten, Bergstrom, & Adami, 1997).
Similar to cervical cancer, anal cancer and its precursor lesions, anal intraepithelial neoplasia (AIN), are highly associated with certain high-risk strains of the human-papilloma virus (HPV) with 84.3% of anal cancer tumours and 92.7% of AIN containing HPV DNA (De Vuyst, Clifford, Nascimento, Madeleine, & Franceschi, 2009). Among Canadian samples of MSM, the most prevalent strain in anal lesions is HPV-16 (Gohy et al., 2008; Lampinen et al., 2006; Salit et al., 2009), which is highly associated with anal cancer (De Vuyst et al., 2009). Despite high rates of preclinical disease being well documented among MSM in the literature (de Pokomandy et al., 2011; Dona et al., 2012; Machalek et al., 2012; Salit et al., 2009; Videla et al., 2013), apart from limited research-based screening programs including the TRACE anal cancer screening study in Toronto (Salit et al., 2009), and the HIPVIRG Cohort Study in Montreal (de Pokomandy et al., 2009), Canadian MSM are not routinely screened (Machalek et al., 2012).
Gaps in our understanding of HPV-related anal disease are frequently cited as primary challenges for implementing screening programs (Darragh & Winkler, 2011, Machalek et al., 2012). One knowledge gap is the rate of progression of untreated AIN to anal cancer. While data from two small studies have reported progression rates of 7.5% (Devaraj & Cosman 2006) and 11% (Watson, Smith, Whitehead, Sykes, & Frizelle 2006), data from large prospective studies providing reliable estimates have not been published (Stanley, Winder, Sterling, & Goon, 2012).
While multiple modalities exist for treatment of AIN, a 2012 Cochrane review (Macaya, Muhoz-Santos, Balaguer, & Barbera, 2012) found only one RCT on AIN treatment. The study reports a statistically significant benefit (p < 0.05) with imiquimod cream compared to placebo (Fox et al., 2010).
Non-controlled studies have shown variable results with trichloroacetic acid (Singh, Kuohung, & Palefsky, 2009) and high-resolution anoscopy (HRA) targeted ablation (Cranston, Hirschowitz, Cortina, and Moe, 2008; Goldstone, Hundert, & Huyett, 2007; Nathan, Hickey, Mayuranathan, Vowler, & Singh, 2008; Pineda et al., 2008). A brief summary of these studies is provided in Table 1. For primary prevention, the quadrivalent-HPV vaccine (Gardasil[R]) was 77.5% effective at preventing anal dysplasia among younger MSM with limited sexual exposure (Palefsky et al., 2011). Although these studies show promise in the effective prevention and treatment of HPV-related AIN, no direct evidence exists to demonstrate that treatment of AIN reduces anal cancer incidence long-term (Pineda et al. 2008; Stanley et al., 2012).
While anal cancer poses an important health risk to MSM, lack of knowledge, clinical guidelines, and HRA infrastructure for screening and treatment of AIN impedes Canadian primary care physicians (PCPs) from addressing this health concern among their MSM patients. In this context, the question of whether Canadian MSM are being provided information on anal cancer risk, and offered available screening and prevention options to potentially reduce morbidity and mortality associated with anal cancer must be asked. Our objectives were to conduct a survey among MSM attending an STI clinic in Ottawa, Ontario to assess: 1) their knowledge of anal cancer risk and its etiology; 2) the importance MSM place on anal cancer as a health issue; 3) whether MSM and their PCPs are having discussions regarding anal cancer screening and prevention; and 4) MSM awareness, acceptance, and uptake of the HPV vaccine.
Survey Development and Ethics
A cross-sectional survey was developed and divided into three sections to specifically address the study's above mentioned objectives. Section one included three questions to assess respondents' knowledge related to anal cancer risk, HPV and HPV immunization (Table 2, Part 1). To gauge importance, respondents were instructed to rank 10 health concerns relevant to MSM, including anal cancer, on a list from one to 10 in terms of importance to them (one = most important issue, 10 = least important issue; Table 3). Data was still included in the analyses if a respondent gave equal rank to two or more of the health concerns listed. Section two asked respondents with a PCP about their openness and comfort discussing anal health with their PCP, whether they discussed anal cancer issues with their PCP, and if they had received any type of anal cancer screening (Table 2, Part 2). The survey's final section focused on HPV vaccination. Questions assessed vaccine uptake among respondents, discussion rates about vaccination with a health care provider, and whether respondents had insurance coverage for the vaccine. Respondents without insurance coverage were asked if they were willing to pay for the full cost of the vaccine (Table 2, Part 3). For respondents unwilling to pay the full vaccine cost, they were asked to specify how much money, if any, they would be willing to pay (Table 4). Ottawa Public Health's Research Ethics Board approved this study in July 2013.
Between August 2013 and January 2014, the cross-sectional survey was administered to men as they registered for health services at an STI testing and treatment clinic in Ottawa, Ontario specifically dedicated to serving the MSM population. Surveys were completed voluntarily and anonymously. Men 18 years of age or older who attended the clinic were eligible to participate.
Descriptive statistics were used to evaluate demographic characteristics and individual responses to survey questions. Pearson's Chi-square ([X.sup.2]) test was used to compare responses between men who had discussed anal cancer issues with their PCP versus men who had not. Binary logistic regression was used to assess differences in anal cancer knowledge based on age. Statistical analyses were completed using IBM SPSS version 22 for Mac.
During the survey administration period, 311 men visited the clinic; 280 participated in the survey (response rate 90.0%). Respondents' mean age was 37 [+ or -] 11.86 years (range 18-69). Slightly more than half of respondents (n = 153; 55.0%) were aware that MSM are more likely to develop anal cancer compared to the general population (Table 2). The most commonly reported sources for such information were news media (n = 53; 34.6%) and STI educational pamphlets (n = 40; 26.1%). Approximately 25% of respondents listed either their PCP (n = 24; 15.7%) or another healthcare provider (n = 15; 9.8%) as their source for anal cancer knowledge. Other sources included family and friends (n = 27; 17.6%) and the internet (n = 19; 12.4%). While only 132 respondents (47.7%) were aware that HPV is the primary cause for anal cancer, 216 (77.7%) were aware of the HPV vaccine to protect against infection (Table 2). From the list of 10 major health concerns relevant to MSM, HIV/AIDS was, on average, ranked higher than anal cancer. Overall, the other eight health issues ranked either similar to or lower than anal cancer (Table 3). By dividing respondents' rankings up based on age group (1834, 35-49 and >49), some minor variations were seen, particularly among the oldest age group (>49 years old). Overall, however, rankings of health concerns were fairly consistent across all three age groups (Table 3).
Of 209 men with a PCP, 187 (89.5%) had either already informed their PCP about having sex with other men or indicated they were comfortable letting their PCP know this information (Table 2). Only 31 men (14.8%), however, reported having a discussion regarding anal cancer prevention and screening with their PCP (Table 2). Of these, 11 men (35.5%) reported they had initiated the conversation, 16 (51.6%) reported that their PCP had initiated the conversation, and four did not specify. Of the remaining respondents, the majority (n = 153; 86.0%) indicated anal health was a subject they would be comfortable discussing with their PCP (Table 2). Only 24 men (11.5%) reported receiving anal cancer screening (Table 2); 10 had received a digital rectal exam (DRE), one received anoscopy, and five had received both (combined total 16 men; 7.7%). Among the other eight, five listed colon cancer screening tests as their anal cancer screening test (colonoscopy, sigmoidoscopy, and fecal occult blood testing), while three did not specify.
Of 272 men completing the survey's third section, 38.6% had either been vaccinated (n = 44, 16.2%) or had discussed the option with a healthcare professional (n = 61; 22.4%; Table 2). Vaccination rate varied among age groups with 20.2% of men aged 35-49 reporting vaccination while only 10.6% of men over the age of 49 reported having been vaccinated. Among men aged 18-34, 15.8% had received the HPV vaccine. Mean age at time of vaccination was 34.5 [+ or -] 10.3 years (range 19-56 years). Among vaccinated men, 28 (63.6%) had insurance coverage for the vaccine. Among men (n = 230) who either did not have insurance coverage or were unsure if their insurance covered the vaccine, 62 (27.0%) indicated they would pay the entire cost of the vaccine despite unknown effectiveness in sexually-active MSM (Table 4). Another 112 (48.7%) were willing to pay part of the vaccine cost while only 23 (10.0%) were unwilling to pay anything (Table 4). Overall, 218 men (80.1%) indicated they had either a) received the vaccine, b) had insurance coverage for the vaccine, or c) were willing to pay for all or part of the vaccine cost.
Men who had discussed anal cancer screening and prevention with their PCP were significantly more knowledgeable about anal cancer and HPV infection than men who had not discussed the subject with their PCP (Table 5). They were also significantly more likely to have been vaccinated; however, there was no statistical difference between these two groups in terms of their willingness to pay for the vaccine (Table 5). Respondents' age was inversely correlated with anal cancer and HPV knowledge (Table 6).
We observed relatively low awareness among MSM of their increased anal cancer risk and its association with HPV. Others have observed similar knowledge gaps among MSM (Blackwell & Eden, 2011; Gilbert, Brewer, Reiter, Ng, & Smith, 2011; Gutierrez et al., 2013). High awareness of the HPV vaccine, notwithstanding the aforementioned knowledge gaps, suggests many MSM may be unaware that the vaccine is relevant to them in terms of anal cancer prevention. Gilbert, Brewer, & Reiter (2011) observed in 2009 that only 21% of American MSM believed HPV vaccination was effective or indicated for males.
We observed a positive association between anal cancer discussions with a PCP and knowledge of anal cancer risk, its association with HPV infection, and uptake of the HPV-quadrivalent vaccine. Despite this, we observed limited discussion between respondents and their PCPs regarding anal cancer risk, prevention, and screening. American (Blackwell & Eden, 2011) and Australian (Pitts, Fox, Willis, & Anderson, 2007) studies also report low rates of discussion about anal cancer between MSM and their PCPs (10.2% and 19.2% respectively). Almost half of our respondents were unaware they were at increased risk of developing anal cancer which may partially explain why they do not broach the subject with their PCP. These findings emphasize the importance for Canadian PCPs to initiate discussions about anal cancer as an inclusive strategy to address and improve anal health among all MSM patients.
Early detection of anal cancer has been shown to lead to decreased morbidity and increased survival (Bilimoria et al., 2009). In view of this, MSM should be aware of the clinical signs and symptoms of anal cancer and PCPs should consider regular screening. Screening modalities include the digital anal rectal exam (DARE) (Berry, Jay, Palefsky, & Welton, 2004; Darragh & Winkler, 2011; Fox, 2009; Jay, 2011), the anal Papanicolaou test (PAP smear) with referral onto HRA for abnormal cytology (Chiao, Giordano, Palefsky, Tyring, & El Serag, 2006; Goldie et al., 1999; Goldie et al., 2000; Nathan et al., 2010; Palefsky et al. 1997), or direct visualization by HRA as first-line screening (Berry et al., 2009; Lam et al., 2011). HRA requires specific infrastructure and training and to the best of our knowledge is currently only available in Montreal, Toronto, Ottawa and Vancouver. Where HRA is not available, the DARE can identify subclinical masses by palpating the anal canal, and can be used as an effective screening tool for both anal and prostate cancers. While the DRE was the most common test performed in our study, it was rarely performed, and we cannot infer from our survey whether the PCP was actually performing a more thorough DARE or simply a routine DRE for prostate screening only. Large-scale trials are needed to demonstrate a mortality benefit to screening and to determine if detection and ablation of precancerous AIN lesions by HRA reduces anal cancer incidence.
While the National Advisory Committee on Immunization (NACI) recommends the quadrivalent-HPV vaccine for all MSM regardless of sexual history (National Advisory Committee on Immunization, 2012), we observed low rates of vaccination among respondents in our survey. Similar to other researchers (Gilbert, Brewer, & Reiter; 2011; Hernandez et al., 2010) we observed high levels of acceptability to HPV vaccination based on respondents' willingness to pay for part or all of the vaccine cost. Despite the recommendations of the NACI, public funding of the HPV vaccine for males only exists in Alberta (grade 5) and PEI (grade 6) (Public Health Agency of Canada, 2015). In addition to being an effective primary prevention intervention among MSM with minimal sexual exposure (Palefsky et al., 2011), there is evidence suggesting HPV-vaccination may prevent recurrent AIN in persons with previously treated lesions (Swedish, Factor, & Goldstone, 2012) .
While this study primarily focused on the relationship between MSM and their PCP in terms of awareness of anal cancer and prevention, as our study demonstrates, only a minority of men who were aware of their increased risk of anal cancer report learning this from their PCP. This highlights the need for a more comprehensive strategy to raise awareness of increased anal cancer risk among MSM that extends beyond the offices of Canadian PCPs. Further research exploring the most appropriate and effective public health interventions to raise awareness will help guide future efforts. A comprehensive strategy would likely include recruiting other community-based health care resources such as the clinic where our survey was conducted and, as advocated by Blackwell & Eden (2011), public awareness campaigns that target events and social media outlets popular among the MSM population.
To our knowledge, this is the first study to assess the knowledge, attitudes, and experience of a Canadian sample of MSM regarding anal cancer screening and prevention. The results of this study provide evidence of the need for PCPs and other healthcare workers working with MSM across Canada to discuss anal cancer etiology, prevention, and screening options with this population.
Our sample was drawn from men who underwent STI testing at a clinic specific for this purpose and designated by name for MSM. This sampling method likely results in an under-sampling of men who see their PCP directly for STI screening and an over-sampling of MSM who are more open about their sexual orientation. These results are therefore not generalizable to all Canadian MSM. The cross-sectional nature of the survey limits the ability to determine casual relationships between attitudes, knowledge, interventions and anal cancer.
The results of this study indicate that a substantial percentage of MSM are not aware of their increased anal cancer risk nor of options for screening and prevention. Our findings indicate a need for further research to explore these knowledge gaps and determine the best way to increase awareness among MSM. While we advocate screening for anal cancer in high risk populations such as MSM, we recognize large-scale studies are required to better direct specific screening recommendations including studies to determine to what extent screening for and treating AIN effectively reduces anal cancer incidence long term in these populations. While awaiting these data, MSM need to be aware of their risk and we recommend that healthcare providers including PCPs initiate discussions with MSM patients about anal cancer. These discussions should include signs and symptoms to be aware of and available screening options. As per the National Advisory Committee on Immunization recommendations, MSM should also be offered HPV-vaccination. Based on this information, better informed MSM will be able to decide, in conjunction with their PCP, the screening and prevention interventions they wish to undergo.
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Andrew Moores, (1) J. Craig Phillips, (2) Patrick O'Byrne, (2) and Paul MacPherson (3)
(1) Sunnybrook Hospitalist Training Program, University of Toronto, Toronto, ON
(2) School of Nursing, University of Ottawa, Ottawa, ON
(3) Department of Medicine, University of Ottawa, Ottawa, ON
Correspondence concerning this article should be addressed to Andrew Moores, MD, CCFP, Clinical Fellow, Sunnybrook Hospitalist Training Program, Toronto, ON. Email: Andrew.email@example.com
Table 1. Summary of studies focused on effectiveness of different treatment modalities of anal intraepithelial neoplasia (AIN). Study Treatment Modality Fox et al., 2010 Imiquimod cream Singh, Kuohung, and Palefsky, Topical trichloroacetic acid 2009 Pineda et al., 2008 HRA-guided needle tip cautery Nathan, Hickey, Mayuranathan, HRA-guided laser ablation Vowler, and Singh, 2008 Goldstone, Hundert, and Huyett, HRA-guided infrared coagulation 2007 (b) Cranston, Hirschowitz, Cortina, HRA-guided infrared coagulation and Moe, 2008 (e) Response Rate (a) Recurrence Rate (mean number of (mean number of months of months after Study follow-up) treatment) Fox et al., 2010 43% (33) 39% (36) Singh, Kuohung, and Palefsky, 49% 72% (6) 2009 Pineda et al., 2008 78% (41) 57% (19) Nathan, Hickey, Mayuranathan, 63% (12) Vowler, and Singh, 2008 Goldstone, Hundert, and Huyett, 47% (18.3) (c) 53% (10.6) (c) 2007 (b) 100% (11.4) (d) 0% (d) Cranston, Hirschowitz, Cortina, 64% (4.6) and Moe, 2008 (e) (a) Definition of response rate varies from study to study. Some studies defined it as clearance of the lesion, while others defined it as either clearance of the lesion or regression from a high-grade to low-grade lesion. (b) The subjects of this study were exclusively HIV-negative MSM (c) Response and recurrence rates after one treatment (d) Response and recurrence rates after three treatments (e)The subjects of this study were exclusively HIV-positive MSM Table 2. Summary of respondents' answers to survey questions requiring a yes/no response. PART ONE Item N Yes (%) Were you aware that men who have sex with 278 153 (55.0%) men are at greater risk than the general population for developing anal cancer? Were you previously aware that anal 277 132 (47.7%) cancer is caused by certain strains of a sexually transmitted virus called HPV? Were you aware that there is currently a 278 216 (77.7%) vaccine available that can prevent infection with certain strains of HPV? PART TWO Do you have a Family Doctor? 279 209 (74.9%) If yes, is your family doctor aware that 208 156 (75.0%) you have sex with other men? If your doctor is unaware that you have 52 31 (59.6%) sex with other men, are you comfortable letting him/her know you have sex with other men? Has your doctor ever talked to you about 209 31 (14.8%) anal cancer prevention and screening? If no, would you feel comfortable 178 153 (86.0%) discussing anal health with your doctor If no, would you feel more comfortable 23 23 (100%) discussing anal health in a clinic specifically for gay men? Have you ever asked your doctor about the 191 5 (2.6%) possibility of having an anal PAP smear done? Has your doctor ever discussed with you 196 24 (12.2%) or performed other screening tests to potentially detect early signs of anal cancer? PART THREE Have you received the Gardasil vaccine to 272 44 (16.2%) protect against HPV infection? If no, have you ever talked to your 224 61 (27.2%) doctor or another healthcare professional about receiving the vaccine? Do you have private healthcare insurance? 273 183 (67%) If yes, does your insurance cover the 181 41 (22.7%) cost of the vaccine for you? Would you be willing to pay the full 213 62 (29.1%) amount of money (approximately $500) for the vaccine considering the effectiveness is unknown in people who are already sexually active? Would you be willing to pay the full 230 142 (61.7%) amount of money (approximately $500) for the vaccine if it was shown to be at least partially effective in people who are already sexually active? PART ONE Item No (%) Unsure (%) Were you aware that men who have sex with 125 (45.0%) men are at greater risk than the general population for developing anal cancer? Were you previously aware that anal 145 (52.3%) cancer is caused by certain strains of a sexually transmitted virus called HPV? Were you aware that there is currently a 62 (22.3%) vaccine available that can prevent infection with certain strains of HPV? PART TWO Do you have a Family Doctor? 70 (25.1%) If yes, is your family doctor aware that 52 (25.0%) you have sex with other men? If your doctor is unaware that you have 21 (40 4%) sex with other men, are you comfortable letting him/her know you have sex with other men? Has your doctor ever talked to you about 178 (85.2%) anal cancer prevention and screening? If no, would you feel comfortable 25 (14.0%) discussing anal health with your doctor If no, would you feel more comfortable 0 (0%) discussing anal health in a clinic specifically for gay men? Have you ever asked your doctor about the 186 (97.4%) possibility of having an anal PAP smear done? Has your doctor ever discussed with you 172 (87.8%) or performed other screening tests to potentially detect early signs of anal cancer? PART THREE Have you received the Gardasil vaccine to 228 (83.8%) protect against HPV infection? If no, have you ever talked to your 163 (72.8%) doctor or another healthcare professional about receiving the vaccine? Do you have private healthcare insurance? 90 (33%) If yes, does your insurance cover the 15 (8.3%) 125 (69.1%) cost of the vaccine for you? Would you be willing to pay the full 143 (67.1%) 8 (3.8%) amount of money (approximately $500) for the vaccine considering the effectiveness is unknown in people who are already sexually active? Would you be willing to pay the full 80 (34.8%) 8 (3.5%) amount of money (approximately $500) for the vaccine if it was shown to be at least partially effective in people who are already sexually active? Note: * p < .05; ** p < .01. Table 3. Anal cancer importance compared to nine other health concerns relevant to the MSM population. Mean Ranking * Health Issue Age Group (N) (Standard Deviation) HIV/AIDS 18-34 (139) 1.35 (0.90) 35-49 (82) 1.40 (1.30) >49 (44) 1.48 (1.50) Overall (265) 1.40 (1.15) Anal Cancer 18-34 (133) 4.10 (2.22) 35-49 (82) 4.18 (2.36) >49 (44) 3.77 (2.23) Overall (259) 4.07 (2.26) Depression and Anxiety 18-34 (136) 4.05 (2.05) 35-49 (81) 3.72 (2.06) >49 (42) 5.14 (1.98) Overall (259) 4.11 (2.09) Drug and alcohol use 18-34 (137) 4.69 (2.14) 35-49 (82) 4.27 (2.08) >49 (43) 4.56 (1.99) Overall (262) 4.52 (2.10) Prostate Cancer 18-34 (135) 4.81 (2.08) 35-49 (79) 4.76 (2.36) >49 (43) 4.53 (2.75) Overall (257) 4.76 (2.29) Discrimination 18-34 (134) 5.64 (2.61) 35-49 (81) 5.71 (2.82) >49 (40) 6.32 (2.39) Overall (255) 5.76 (2.64) Heart Disease 18-34 (133) 6.21 (2.36) 35-49 (79) 5.82 (2.19) >49 (41) 5.31 (2.16) Overall (253) 5.94 (2.29) Cigarette Smoking 18-34 (134) 7.39 (8.26) 35-49 (80) 6.78 (2.20) >49 (41) 6.56 (2.40) Overall (255) 6.71 (2.21) Obesity 18-34 (133) 7.90 (2.11) 35-49 (81) 7.46 (2.46) >49 (41) 7.63 (2.54) Overall (255) 7.73 (2.30) Aging 18-34 (129) 8.16 (2.43) 35-49 (81) 8.10 (2.21) >49 (41) 7.53 (2.00) Overall (251) 8.04 (2.30) Median Most Common Health Issue Age Group (N) Ranking * Ranking * (n) HIV/AIDS 18-34 (139) 1 1 (113) 35-49 (82) 1 1 (70) >49 (44) 1 1 (38) Overall (265) 1 1 (222) Anal Cancer 18-34 (133) 4 2 (44) 35-49 (82) 4 2 (19) >49 (44) 3 2 (18) Overall (259) 4 2 (82) Depression and Anxiety 18-34 (136) 4 4 (26) 35-49 (81) 3 3 (19) >49 (42) 5 3 (12) Overall (259) 4.0 3 (51) Drug and alcohol use 18-34 (137) 4 4 (26) 35-49 (82) 4 3 (18) >49 (43) 4 5 (8) Overall (262) 4.0 3 (51) Prostate Cancer 18-34 (135) 5 3 (34) 35-49 (79) 4.5 3 (13) >49 (43) 4 2 (9) Overall (257) 4.0 3 (52) Discrimination 18-34 (134) 5 4 (20) 35-49 (81) 5 9 (12) >49 (40) 7 9 (9) Overall (255) 5.0 5 and 9 (38) Heart Disease 18-34 (133) 7 8 (23) 35-49 (79) 6 6 (20) >49 (41) 5 4 (11) Overall (253) 6.0 6 (40) Cigarette Smoking 18-34 (134) 7 8 (26) 35-49 (80) 7 7 (20) >49 (41) 7 7 (9) Overall (255) 7.0 7 (51) Obesity 18-34 (133) 8 10 (33) 35-49 (81) 8 10 (21) >49 (41) 9 10 (14) Overall (255) 8.5 10 (69) Aging 18-34 (129) 9 10 (54) 35-49 (81) 9 10 (31) >49 (41) 8 9 (8) Overall (251) 9.0 10 (93) Note: * One = most important issue, 10 = least important issue. Table 4. HPV vaccine costs under- or uninsured respondents were willing to pay. Amount Frequency Percent of Willing to Pay (n) Respondents Full cost 62 27.0 $300 9 3.9 $200 16 7.0 $150 2 0.9 $100 52 22.6 $50 30 13.0 $10 3 1.3 $0 23 10.0 Not specified 33 14.3 Total 230 100.0 Table 5. Group comparisons between respondents who had discussed anal cancer screening and prevention with their primary care physician (PCP) versus those who had not. Pearson's Chi Square Statistic was used. Have discussed screening/prevention with their PCP n (%) Knowledge Aware That: MSM at greater risk for 26 (86.7) developing anal cancer Anal cancer caused by certain 21 (70.0) strains of HPV Vaccine available to protect 28 (93.3) against certain strains of HPV Openness to Vaccine Received the vaccine 11 (35.5) Willing to pay full cost for 10 (43.5) vaccine with unknown efficacy in sexually active people Willing to pay full cost for 15 (62.5) vaccine if at least partial protection were to be demonstrated in sexually active people Have not discussed screening/prevention Pearson's with their PCP Chi-Square n (%) P-value Knowledge Aware That: MSM at greater risk for 94 (53.1) 0.001 developing anal cancer Anal cancer caused by certain 77 (43.8) 0.008 strains of HPV Vaccine available to protect 136 (76.8) 0.018 against certain strains of HPV Openness to Vaccine Received the vaccine 30 (17.1) 0.018 Willing to pay full cost for 47 (32.4) 0.457 vaccine with unknown efficacy in sexually active people Willing to pay full cost for 97 (66.4) 0.541 vaccine if at least partial protection were to be demonstrated in sexually active people Note: This table only includes responses from participants with a primary care physician who completed the second section of the survey. Table 6. Logistic regression test parameters to determine differences based on age of respondent. Wald Question B (SE) Statistic Sig. Knowledge Aware That: MSM at Greater Risk for Anal -0.028 (0.010) 6.996 0.008 Cancer Anal Cancer Caused by Certain -0.040 (0.011) 13.63 0.000 Strains of HPV Vaccine Available to Protect -.034 (0.012) 8.015 .005 Against Certain Strains of HPV 95% C.I., Odds ratio Odds Question ratio Lower Upper Knowledge Aware That: MSM at Greater Risk for Anal 0.973 0.953 0.993 Cancer Anal Cancer Caused by Certain 0.960 0.940 0.981 Strains of HPV Vaccine Available to Protect .967 .944 .990 Against Certain Strains of HPV
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|Author:||Moores, Andrew; Phillips, J. Craig; O'Byrne, Patrick; MacPherson, Paul|
|Publication:||The Canadian Journal of Human Sexuality|
|Date:||Dec 1, 2015|
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