The Institutional Review Boards of The Ohio State University, the University of Michigan, and the Centers for Disease Control and Prevention (CDC) approved this study.

This study was part of the Community Awareness, Resources, and Education (CARE) Project, one of eight Centers for Population Health and Health Disparities (P50) funded by the National Institutes of Health (NIH). We report on one component of the CARE Project, a case-control study that focused on the determinants of abnormal cervical cytology among women living in Appalachian Ohio. A secondary aim of this study was to examine HPV prevalence among these women, the focus of this report. Appalachian Ohio is a 32 county region (29 at the time of this study) located in the southern and eastern sections of Ohio. Cervical cancer incidence and mortality rates are 12% and 21% higher, respectively, in Appalachian Ohio counties compared to the non-Appalachian counties in Ohio [10]. We conducted the current study between January 2006 and December 2008. Data from the CARE Project are available upon request.

Women included in this study were from 17 participating health clinics located throughout the Appalachian Ohio region. Women were eligible to participate if they were: 1) age 18 or older; 2) a resident of an Appalachian Ohio county; 3) had an intact uterine cervix and corpus; 4) were not pregnant; 5) did not have a history of cervical cancer; and 6) provided written informed consent. Women scheduled for a routine Papanicolaou (Pap) test on a day that a study nurse was at one of 17 clinics were asked to participate in the study. Women completed a self-administered questionnaire following consent and prior to undergoing their Pap test. During the visit, the provider took an additional research cytology sample and obtained a cervical sample in specimen transport medium (STM; Qiagen Inc., Valencia, CA) for HPV testing.

Women with abnormal cervical cytology at study entry were considered cases for the case-control study that aimed to identify the determinants of abnormal cervical cytology. Women were classified as having abnormal cervical cytology according to the 2001 Bethesda System for Reporting Pap Smear Results [16]. Using this system, cases were classified as having atypical squamous cells of undetermined significance (ASC-US), atypical squamous cells cannot exclude HSIL (ASC-H), atypical glandular cells (AGC), low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesions (HSIL), adenocarcinoma in situ (AIS), or carcinoma. We randomly selected three women with normal cervical cytology at study entry from the same clinic within a three-month window around the date of the case’s abnormal cervical cytology to serve as controls. This part of the CARE Project had a participation rate of 70% [17], with a total of 1131 women included in the case-control study. We report data on 1116 women (278 cases, 838 controls), excluding 15 women with inadequate HPV results.

The STM sample was stored at –70°C until shipped to the Centers for Disease Control and Prevention (CDC). At CDC, the samples were thawed and 150 µL of the 1.0 mL sample were extracted with the MagNA Pure DNA kit III (Roche Applied Science, Indianapolis, IN), with 10 µL of extract used in the Research Use Only (RUO) Linear Array (LA) HPV Genotyping Test (Roche Diagnostics, Indianapolis, IN). The LA assay detects 37 HPV types (6, 11, 16, 18, 26, 31, 33, 35, 39, 40, 42, 45, 51, 52, 53, 54, 55, 56, 58, 59, 61, 62, 64, 66, 67, 68, 69, 70, 71, 72, 73, 81, 82, 83, 84, 89, and IS39) and includes ß-globin as an endogenous positive control. Samples positive for the XR probe on the LA HPV strip that were also positive for HPV 33, 35, and 58 were tested with an HPV 52 quantitative PCR assay to confirm or exclude the presence of HPV 52 [18]. Samples negative for both ß-globin and HPV were considered inadequate for interpretation and omitted from analyses.

Based on HPV testing results, we examined detection of: 1) any HPV type; 2) a high-risk HPV type (16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 64, 66, 67, 68, 69, 70, 73, 82, or IS39); 3) a low-risk HPV type (6, 11, 40, 42, 54, 55, 61, 62, 71, 72, 81, 83, 84, or 89); and 4) a vaccine-preventable HPV type (i.e., a type included in the quadrivalent HPV vaccine [19]: type 6, 11, 16, or 18). We used the same high- and low-risk classification scheme as a recent national study that analyzed data from the National Health and Nutrition Examination Survey (NHANES) [4] in order to facilitate comparisons between data from the CARE Project and the NHANES. For descriptive purposes, we also examined the detection of high-risk HPV types using a classification scheme from the International Agency for Research on Cancer (IARC)(types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68; Groups 1 and 2A of the IARC scheme)[20]. Lastly, we examined the detection of each individual HPV type and detection of multiple HPV types (i.e., women testing positive for two or more HPV types). We do not, however, report detailed data on multiple-type HPV infections (e.g., HPV types present in the multiple-type infections). We feel such detailed data are beyond the scope of this manuscript, but the data will be considered for a future publication.

We collected data on a wide range of health-related and demographic characteristics and examined them as potential correlates of HPV detection (Table 1). Data on potential correlates were obtained during the self-administered questionnaire that women completed prior to undergoing their cervical cancer screening test upon study entry.

We examined women’s smoking status (never smoker, former smoker, or current smoker) and whether they had ever been pregnant. We collected information on women’s cervical cancer screening histories and determined if they had a Pap test within the three years prior to study entry and whether they ever had a previous abnormal Pap test. Women indicated if they had ever been told by a doctor that they had an HPV infection (described to women as venereal warts, condylomas, or a papillomavirus infection). Women also indicated their age at first sexual intercourse, number of male sexual partners during their lifetime, number of male sexual partners within the last year, if any of their male partners had been diagnosed with an STI, and if they had any female sexual partners during their lifetime. We collected data on several demographic characteristics, including age, race/ethnicity, marital status, education, and annual household income. Age was categorized as 18–26 years old (within the recommended age range for HPV vaccination [19]), 27–39 years old, and 40 years or older.

We first calculated descriptive statistics in examining the prevalence of HPV among participants. We then used logistic regression to identify correlates of two outcomes: detection of any HPV type and detection of a high-risk HPV type (using the same classification scheme for high-risk HPV types as a recent study that analyzed data from the NHANES) [4]). For each outcome, we entered statistically significant univariable correlates (p<0.05) into a multivariable logistic regression model. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were obtained from these multivariable logistic regression models. All logistic regression models included health clinic as a random effect since women were clustered within health clinics. Data were analyzed using SAS Version 9.2 (SAS Institute Inc., Cary, NC) and all statistical tests were two-tailed, using a critical value of α = 0.05.

Most women were less than 40 years old (67.8%), non-Hispanic white (93.9%), had at least a high school degree (88.2%), and reported a household income of $50,000 or less (82.3%)(Table 1). Less than half of women were married or a member of a couple (48.4%) and about a third indicated that they had never been married (33.3%). Over 40% of women (42.4%) were current smokers with an additional 15.1% being former smokers. A majority of women (85.5%) reported receiving a Pap test in the three years prior to study enrollment. Although 43.9% of women reported a history of at least one prior abnormal Pap test, only 11.5% indicated that a doctor had ever told them they had venereal warts, condylomas, or a papillomavirus infection. Most women reported they were age 16 or older at the time of their first sexual intercourse (67.8%) and just over half (55.1%) reported having at least five male sexual partners during their lifetime. Among women with an abnormal Pap test upon entry into the CARE Project (i.e., cases; n = 278), 143 (51.4%) had ASC-US, 7 (2.5%) had AGC, 112 (40.3%) had LSIL, 15 (5.4%) had HSIL, and 1 (0.4%) had squamous cell carcinoma.

The overall prevalence of any HPV type, as measured by HPV DNA detection in the LA assay, was 43.1% (Table 2). Using the same classification scheme as a recent study that analyzed data from the NHANES [4], a high-risk HPV type was detected in 33.5% of women while a low-risk HPV type as detected in 23.4% of women. Using the classification scheme from IARC [20], a high-risk HPV type was detected in 27.9% of women. A vaccine-preventable HPV type (6, 11, 16, or 18) was detected in 12.5% of women, including 21.0% of women ages 18–26. Among all women, HPV type-specific prevalence ranged from 0.0% to 8.2% (Table 3). The most prevalent HPV types included types 16 (8.2%), 53 (5.7%), 62 (4.8%), 51 (4.7%), 84 (4.6%), 89 (4.5%), 66 (4.3%), and 39 (4.1%). All other HPV types had a prevalence of less than 4.0%, including types 18 (2.7%), 6 (2.2%), and 11 (0.3%). Over 20% of women (22.4%) had two or more HPV types detected.

In multivariable analyses, detection of any HPV type was more common among women ages 18-26 compared to women ages 40 or older (OR = 2.09, 95% CI: 1.26–3.50)(Table 4). Current smokers were more likely to be HPV-positive compared to never smokers (OR = 1.86, 95% CI: 1.26–2.73). Detection of any HPV type was also more common among women with an abnormal Pap test upon entry into the CARE Project (OR = 5.59, 95% CI: 3.73–8.37), at least five male sexual partners during their lifetime (OR = 2.28, 95% CI: 1.56–3.33), or multiple male sexual partners during the last year (OR = 1.98, 95% CI: 1.25–3.14).

Multivariable correlates of high-risk HPV detection were highly similar to those for detection of any HPV type (Table 5). Detection of a high-risk HPV type was more common among women ages 18-26 compared to women ages 40 or older (OR = 3.25, 95% CI: 1.86–5.66) and among current smokers compared to never smokers (OR = 1.52, 95% CI: 1.01–2.30). Detection was also more common among women with a previous abnormal Pap test (OR = 1.51, 95% CI: 1.04–2.21), an abnormal Pap test upon entry into the CARE Project (OR = 6.26, 95% CI: 4.19–9.37), at least five male sexual partners during their lifetime (OR = 2.57, 95% CI: 1.69–3.92), or multiple male sexual partners during the last year (OR = 1.70, 95% CI: 1.07–2.69).

The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the funding agencies.