Lifestyle Correlates of Female Snus Use and Smoking: A Large Population-Based Survey of Women in Norway.

INTRODUCTION: While smoking in Norway has become less prevalent, snus use has increased, including among women. The aims of this study were to describe female snus use and its correlates, and to contrast patterns of snus use and smoking. METHODS: In 2011-2012, data on tobacco use, age, education, alcohol consumption, sexual behaviors, and physical activity were collected from a population based sample of 13 756 Norwegian women aged 18-45 years, using a self-administered questionnaire. RESULTS: Ever-use prevalence of snus ranged from 29.6% to 4.5% among those aged 18-19 years and 40-45 years, respectively. In contrast, the corresponding figures for smoking were 24.1% and 44.1%. Among snus users, 54.1% and 22.8% of 18-19 and 40 to 45-year-olds had never smoked, respectively. Debut age for snus use increased markedly with age, and was higher than debut age for smoking. Female snus use was positively associated with intermediate education, alcohol consumption, number of sexual partners, and hard physical activity. Smoking was also positively associated with alcohol consumption and number of sexual partners, but negatively associated with physical activity and education. CONCLUSION: While most snus users among older women were former or current smokers, this was not the case among younger women. Low snus debut age and extensive snus use among younger women suggest that measures to reduce snus use should be targeted at young adolescents. The correlates of female snus use and smoking were not identical, and were similar to those previously documented for men.

Cervical cancer prevented by screening: Long-term incidence trends by morphology in Norway.

Both major morphologic types of cervical cancer, squamous cell carcinoma (SCC) and adenocarcinoma (AC), are causally related to persistent infection with high-risk human papillomavirus (hrHPV), but screening has primarily been effective at preventing SCC. We analysed incidence trends of cervical cancer in Norway stratified by morphologies over 55 years, and projected SCC incidence in the absence of screening by assessing the changes in the incidence rate of AC. The Cancer Registry of Norway was used to identify all 19,530 malignancies in the cervix diagnosed in the period 1956-2010. The majority of these (82.9%) were classified as SCCs, 10.5% as ACs and the remaining 6.6% were of other or undefined morphology. By joint-point analyses of a period of more than five decades, the average annual percentage change in the age-standardised incidence was -1.0 (95%CI: -2.1-0.1) for cervical SCC, 1.5 (95%CI:1.1-1.9) for cervical AC and -0.9 (95%CI: -1.4 to -0.3) for cervical cancers of other or undefined morphology. The projected age-standardised incidence rate of cervical SCC in Norway, assuming no screening, was 28.6 per 100,000 woman-years in 2010, which compared with the observed SCC rate of 7.3 corresponds to an estimated 74% reduction in SCC or a 68% reduction due to screening in the total cervical cancer burden. Cytology screening has impacted cervical cancer burden more than suggested by the overall observed cervical cancer incidence reduction since its peak in the mid-1970s. The simultaneous substantial increase in cervical adenocarcinoma in Norway is presumably indicative of an increase in exposure to HPV over time.

Correlates of HPV vaccine uptake in school-based routine vaccination of preadolescent girls in Norway: A register-based study of 90,000 girls and their parents.

OBJECTIVE: To assess demographic, socioeconomic and behavioural correlates of HPV vaccination of preadolescent girls in a publicly funded, school-based vaccination programme. METHODS: Data for all Norwegian girls born 1997-1999, eligible for routine school-based HPV vaccination in 2009-2011 (n=90,842), and their registered mother and father, were merged from national registries. Correlates of girl vaccination status were analysed by unadjusted and multivariable logistic regression. RESULTS: In total, 78.2% of the girls received the first dose of the HPV vaccine, 74.6% received three doses, and 94.8% received the MMR vaccine. Correlates associated with initiation of HPV vaccination included parental age, income and education, maternal occupational status and cervical screening attendance, and girl receipt of the MMR vaccine. Rates of completion of HPV vaccination among initiators were high, and disparities in completion were negligible. Maternal and paternal correlates of daughter HPV vaccination status were similar. CONCLUSIONS: Routine school-based vaccination generally provides equitable delivery, yet some disparities exist. Information campaigns designed to reach the sub-groups with relatively low vaccine uptake could reduce disparities. In none of the sub-groups investigated did uptake of the HPV vaccine approach that of the MMR vaccine, further demonstrating a general potential for improvement in HPV vaccine uptake.

Quality assessment of the registration of vulvar and vaginal premalignant lesions at the Cancer Registry of Norway.

BACKGROUND: A crucial factor concerning the utility of Cancer Registries is the data quality with respect to comparability, completeness, validity and timeliness. However, the data quality of the registration of premalignant lesions has rarely been addressed. High grade vulvar intraepithelial neoplasia (VIN) and vaginal intraepithelial neoplasia (VaIN) are premalignant lesions which may develop into cancer, and are often associated with infection with the human papillomarvirus (HPV). The aim was to evaluate the quality of registration of VIN and VaIN at the Cancer Registry of Norway (CRN). MATERIAL AND METHODS: We re-collected all notifications with high grade VIN and VaIN diagnoses during 2002 to 2007 from pathology laboratories, and compared these to the data in the CRN database so as to quantitatively measure the completeness, validity and timeliness of the data. RESULTS: Over the period 2002 to 2007 we estimated the completeness of the 1556 VIN and 297 VaIN notifications to be 95.0% and 92.9%, respectively. The original and reabstracted topography codes showed major discrepancies for 12 of 642 (1.9%) VIN and 7 of 128 (5.5%) VaIN notifications. The original and reabstracted morphology codes for VIN and VaIN were identical for 724 out of 814 notifications. Sixteen notifications had a major discrepancy. For the period 2002 to 2007 the median time elapsed between date of diagnosis and date of registration were 436 and 441 days for VIN and VaIN cases, respectively. DISCUSSION: Based on the present analysis of the comparability, completeness, validity and timeliness of premalignant lesions of vulva and vagina, we conclude that the Cancer Registry of Norway is able to monitor such premalignant lesions satisfactorily.

Young age at first intercourse and risk-taking behaviours--a study of nearly 65 000 women in four Nordic countries.

BACKGROUND: Risk-taking behaviours such as early initiation of smoking, alcohol drinking and sexual activity often cluster within individuals and could be characteristics of adolescents who in general are risk takers. In the present study, using a large population-based sample of 64 659 women aged 18-45 years in four Nordic countries, we investigate whether young age at first sexual intercourse is associated with subsequent risk-taking behaviours. METHODS: We examined the association between young age at first sexual intercourse (age ≤14 years) and subsequent risk-taking behaviours by using multivariate logistic regression by which odds ratios (ORs) and the corresponding 95% confidence intervals (95% CIs) were estimated. RESULTS: The OR of reporting more than 10 lifetime sexual partners was almost four times higher among women who reported a young age at first intercourse (OR = 3.79; 95% CI: 3.60-4.00) in comparison with women >14 years at first intercourse. Furthermore, women who were young at first intercourse were more likely to report two or more recent partners (OR = 1.67; 95% CI: 1.54-1.82) and to have a history of STIs (OR = 2.03; 95% CI: 1.93-2.13). In addition, young age at first intercourse was associated with current smoking (OR = 2.31; 95% CI: 2.20-2.43) and binge drinking (OR = 1.36; 95% CI: 1.28-1.44). All ORs were adjusted for age, years of education and country of residence. CONCLUSION: Young age at first intercourse is associated with subsequent risk-taking behaviours. Our study emphasizes the importance of targeting prevention efforts towards the complexity of risk-taking behaviours.

Genital chlamydia, genital herpes, Trichomonas vaginalis and gonorrhea prevalence, and risk factors among nearly 70,000 randomly selected women in 4 Nordic countries.

BACKGROUND: The aim of this study was to assess the prevalence of women reporting ever having genital chlamydia, genital herpes, Trichomonas vaginalis, and gonorrhea, and to identify factors associated with each of these sexually transmitted infections (STIs). METHODS: The study was based on a large cross-sectional survey conducted in 2004-2005 among randomly sampled women (18-45 years) from the computerized population registries in Denmark, Iceland, Norway, and Sweden. A total of 69,567 women were included in the study. RESULTS: The overall prevalence in Denmark, Iceland, Norway, and Sweden was 1.5% for reporting ever having had Trichomonas vaginalis, 1.9% for gonorrhea, 4.8% for genital herpes, and 17.0% for genital chlamydia. The prevalence of each of these STIs varied with birth cohort and country. In addition, they were strongly associated with lifetime number of partners and having a previous diagnosis of another sexually transmitted infection. Moreover, a diagnosis of genital chlamydia or gonorrhea was associated with early age at first intercourse and smoking initiation. Finally, reporting genital chlamydia was associated with early age at drinking initiation, and ever use of hormonal contraceptives and condoms. CONCLUSION: Genital chlamydia occurs frequently among women in the Nordic countries. Risk-taking behavior, particularly sexual behavior, is strongly associated with STIs, which suggest that further information is needed about STIs and their consequences, targeting high-risk groups. There is also a need for continued monitoring of STIs in order to follow the prevalence and to gain further knowledge about risk factors.

Association between smoking and genital warts: longitudinal analysis.

OBJECTIVES: To assess the association between smoking and the reported clinical diagnosis of genital warts. METHODS: A sample of 58,094 women (aged 18-45) randomly drawn from the general female population of Denmark, Iceland, Norway and Sweden answered a questionnaire on lifestyle and health. Longitudinal data were reconstructed based on self report of age-specific events. In a Cox regression model, women who reported having been clinically diagnosed with genital warts were followed up until the age at first diagnosis, while women who reported never having been diagnosed with genital warts were censored at the age of interview. Age-specific smoking doses and ages at onset of smoking, sexual intercourse, condom use, hormonal contraceptive use, first pregnancy and alcohol drinking were included in the model as time-dependent covariates. The model also included lifetime number of coital partners and country of origin as fixed covariates. RESULTS: Ever-smokers reported a lower age at first intercourse and more coital partners than never-smokers. The adjusted model showed that sexual behaviour strongly influenced the risk of being diagnosed with genital warts, and that smokers in addition had an increased risk compared with non-smokers (adjusted HR=1.27, 95% CI 1.17 to 1.37). There was also a modest additional dose-response effect of smoking, with smokers experiencing a 0.6% increased risk of being diagnosed with genital warts for each additional cigarette smoked daily (adjusted HR=1.006, 95% CI 1.001 to 1.012). CONCLUSIONS: Smokers experienced a moderately increased risk of being diagnosed with genital warts. This finding could be explained by the immunosuppressive effects of nicotine, or by confounding not accounted for in the adjusted model.

Early smoking initiation, sexual behavior and reproductive health - a large population-based study of Nordic women.

OBJECTIVE: To investigate associations between early smoking initiation, risk-taking behavior and reproductive health. METHOD: A random sample of 69,486 women aged 18-45 from Denmark, Iceland, Norway and Sweden was surveyed in 2004-2005. We compared behavior and health among women who initiated smoking early (before age 15), later (at 15 or later) and never smokers. RESULTS: Adult women who initiated smoking early reported more lifetime and recent sexual partners and less condom use than women who initiated smoking later, and they had lower debut ages for coitus, pregnancy and alcohol consumption. Experiences of teenage pregnancy, abortion/miscarriage and having had at least one sexually transmitted infection (gonorrhea, herpes simplex, trichomonas vaginalis, chlamydia, genital warts) were more frequent among early than among later smoking initiators. Never smoking women reported fewer partners, later debut ages, and more condom use and were less likely to have experienced teenage pregnancy, abortion/miscarriage and having had at least one sexually transmitted infection than either group of smokers. CONCLUSION: Early smoking initiators were more likely to engage in risk-taking behavior and experience adverse reproductive events than were smokers who initiated later. Age at smoking initiation may be an indicator of future reproductive health. Early smoking initiators represent targets for reproductive health information.

Perspectives of non-attenders for cervical cancer screening in Norway: a qualitative focus group study.

OBJECTIVE: The attendance rate for cervical cancer screening in Norway is currently suboptimal at 69%, and an in-depth understanding of postponement of cervical cancer screening from the perspective of non-attenders is lacking. This study aims to generate knowledge about how non-attenders for cervical cancer screening reflect on booking a screening appointment. METHODS: Using the Norwegian cervical cancer screening registry, we identified and recruited women who were non-attenders to screening. Nine focus group interviews were carried out, with 41 women participating in the interviews. RESULTS: Four main themes were generated, which provide a comprehensive understanding of how women who are overdue for screening reflect on their hesitancy to book a screening appointment: 'It's easy to forget about it', 'Women have to arrange their own appointment', 'It has to be a 'must'' and 'It's a humiliating situation'. CONCLUSION: The degree to which women regard screening as important is affected by the nudging strategies employed in the screening programme and the facilitation of attendance provided by healthcare services. Dependence on one's personal initiative to schedule a screening appointment and perception of a lack of responsibility on the part of healthcare services to attend screening may undermine informed and shared decision-making about screening attendance.

FightHPV: Design and Evaluation of a Mobile Game to Raise Awareness About Human Papillomavirus and Nudge People to Take Action Against Cervical Cancer.

BACKGROUND: Human papillomavirus (HPV) is the most common sexually transmitted infection globally. High-risk HPV types can cause cervical cancer, other anogenital cancer, and oropharyngeal cancer; low-risk HPV types can cause genital warts. Cervical cancer is highly preventable through HPV vaccination and screening; however, a lack of awareness and knowledge of HPV and these preventive strategies represents an important barrier to reducing the burden of the disease. The rapid development and widespread use of mobile technologies in the last few years present an opportunity to overcome this lack of knowledge and create new, effective, and modern health communication strategies. OBJECTIVE: This study aimed to describe the development of a mobile app called FightHPV, a game-based learning tool that educates mobile technology users about HPV, the disease risks associated with HPV infection, and existing preventive methods. METHODS: The first version of FightHPV was improved in a design-development-evaluation loop, which incorporated feedback from a beta testing study of 40 participants, a first focus group of 6 participants aged between 40 and 50 years and a second focus group of 23 participants aged between 16 and 18 years. Gameplay data from the beta testing study were collected using Google Analytics (Google), whereas feedback from focus groups was evaluated qualitatively. Of the 29 focus group participants, 26 returned self-administered questionnaires. HPV knowledge before and after playing the game was evaluated in the 22 participants from the second focus group who returned a questionnaire. RESULTS: FightHPV communicates concepts about HPV, associated diseases and their prevention by representing relationships among 14 characters in 6 episodes of 10 levels each, with each level being represented by a puzzle. Main concepts were reinforced with text explanations. Beta testing revealed that many players either failed or had to retry several times before succeeding at the more difficult levels in the game. It also revealed that players gave up at around level 47 of 60, which prompted the redesign of FightHPV to increase accessibility to all episodes. Focus group discussions led to several improvements in the user experience and dissemination of health information in the game, such as making all episodes available from the beginning of the game and rewriting the information in a more appealing way. Among the 26 focus group participants who returned a questionnaire, all stated that FightHPV is an appealing educational tool, 69% (18/26) reported that they liked the game, and 81% (21/26) stated that the game was challenging. We observed an increase in HPV knowledge after playing the game (P=.001). CONCLUSIONS: FightHPV was easy to access, use, and it increased awareness about HPV infection, its consequences, and preventive measures. FightHPV can be used to educate people to take action against HPV and cervical cancer.

Joint occurrence of Merkel cell carcinoma and non-Hodgkin lymphomas in four Nordic countries.

The objective of this study was to assess the reciprocal association between non-Hodgkin lymphoma (NHL) and Merkel cell carcinoma (MCC) using the data of four Nordic Cancer Registries. Data for this study were drawn from the Danish, Finnish, Norwegian, and Swedish cancer registries. Standardized incidence ratios (SIRs) for MCC among NHL patients, and for NHL among MCC patients, were calculated. There were 109 838 individuals with NHL and 1411 individuals with MCC, of which 28 had joint occurrence of NHL and MCC. In 18 cases, NHL was diagnosed first, and in 10 cases, MCC was diagnosed first. The SIR for MCC after NHL was 4.34 (95% confidence interval 2.57-6.85). The SIR for NHL after MCC was 3.13 (1.50-5.77). Although the absolute frequency of joint occurrence of MCC and NHL is low, individuals suffering from one of the cancer forms have an increased risk of the other.

Targeting human papillomavirus to reduce the burden of cervical, vulvar and vaginal cancer and pre-invasive neoplasia: establishing the baseline for surveillance.

BACKGROUND: Infection with high-risk human papillomavirus (HPV) is causally related to cervical, vulvar and vaginal pre-invasive neoplasias and cancers. Highly effective vaccines against HPV types 16/18 have been available since 2006, and are currently used in many countries in combination with cervical cancer screening to control the burden of cervical cancer. We estimated the overall and age-specific incidence rate (IR) of cervical, vulvar and vaginal cancer and pre-invasive neoplasia in Denmark, Iceland, Norway and Sweden in 2004-2006, prior to the availability of HPV vaccines, in order to establish a baseline for surveillance. We also estimated the population attributable fraction to determine roughly the expected effect of HPV16/18 vaccination on the incidence of these diseases. METHODS: Information on incident cervical, vulvar and vaginal cancers and high-grade pre-invasive neoplasias was obtained from high-quality national population-based registries. A literature review was conducted to define the fraction of these lesions attributable to HPV16/18, i.e., those that could be prevented by HPV vaccination. RESULTS: Among the four countries, the age-standardised IR/105 of cervical, vaginal and vulvar cancer ranged from 8.4-13.8, 1.3-3.1 and 0.2-0.6, respectively. The risk for cervical cancer was highest in women aged 30-39, while vulvar and vaginal cancers were most common in women aged 70+. Age-standardised IR/105 of cervical, vulvar and vaginal pre-invasive neoplasia ranged between 138.8-183.2, 2.5-8.8 and 0.5-1.3, respectively. Women aged 20-29 had the highest risk for cervical pre-invasive neoplasia, while vulvar and vaginal pre-invasive neoplasia peaked in women aged 40-49 and 60-69, respectively. Over 50% of the observed 47,820 incident invasive and pre-invasive cancer cases in 2004-2006 can be attributed to HPV16/18. CONCLUSION: In the four countries, vaccination against HPV 16/18 could prevent approximately 8500 cases of gynecological cancer and pre-cancer annually. Population-based cancer and vaccination registries are essential to assess the predicted public health effects of HPV vaccination.