Survival after antireflux surgery versus medication in patients with reflux oesophagitis or Barrett's oesophagus: multinational cohort study.

BACKGROUND: The aim was to examine the hypothesis that antireflux surgery with fundoplication improves long-term survival compared with antireflux medication in patients with reflux oesophagitis or Barrett's oesophagus. METHOD: Individuals aged between 18 and 70 years with reflux oesophagitis or Barrett's oesophagus (intestinal metaplasia) documented from in-hospital and specialized outpatient care were selected from national patient registries in Denmark, Finland, Iceland, and Sweden from 1980 to 2014. The study investigated all-cause mortality and disease-specific mortality, comparing patients who had undergone open or laparoscopic antireflux surgery with fundoplication versus those using antireflux medication. Multivariable Cox regression analysis was used to estimate hazard ratios (HRs) with 95 per cent confidence intervals for all-cause mortality and disease-specific mortality, adjusted for sex, age, calendar period, country, and co-morbidity. RESULTS: Some 240 226 patients with reflux oesophagitis or Barrett's oesophagus were included, of whom 33 904 (14.1 per cent) underwent antireflux surgery. The risk of all-cause mortality was lower after antireflux surgery than with use of medication (HR 0.61, 95 per cent c.i. 0.58 to 0.63), and lower after laparoscopic (HR 0.56, 0.52 to 0.60) than open (HR 0.80, 0.70 to 0.91) surgery. After antireflux surgery, mortality was decreased from cardiovascular disease (HR 0.58, 0.55 to 0.61), respiratory disease (HR 0.62, 0.57 to 0.66), laryngeal or pharyngeal cancer (HR 0.35, 0.19 to 0.65), and lung cancer (HR 0.67, 0.58 to 0.80), but not from oesophageal cancer (HR 1.05, 0.87 to 1.28), compared with medication, The decreased mortality rates generally remained over time. CONCLUSION: In patients with reflux oesophagitis or Barrett's oesophagus, antireflux surgery is associated with lower mortality from all causes, cardiovascular disease, respiratory disease, laryngeal or pharyngeal cancer, and lung cancer, but not from oesophageal cancer, compared with antireflux medication.

Occupation and cutaneous melanoma: a 45-year historical cohort study of 14·9 million people in five Nordic countries.

BACKGROUND: The age-adjusted incidence of cutaneous melanoma (CM) in the Nordic countries has increased during the last 60 years. Few prospective population-based studies have estimated the occupational variation in CM risk over time. OBJECTIVES: To determine occupational variation in CM risk. METHODS: A historical prospective cohort study with a 45-year follow-up from 1961 to 2005 (Nordic Occupational Cancer Study, NOCCA) based on record linkages between census and cancer registry data for Nordic residents aged 30-64 years in Denmark, Finland, Iceland, Norway and Sweden. National occupational codes were converted to 53 occupational categories, and stratified into indoor, outdoor and mixed work, and into socioeconomic status. The standardized incidence ratios (SIRs) were estimated as observed number of CM cases divided by the expected number calculated from stratum-specific person-years and national CM incidence rates. RESULTS: During a follow-up of 385 million person-years, 83 898 incident cases of CM were identified. In all countries combined, men with outdoor work had a low SIR of 0·79 [95% confidence interval (CI) 0·77-0·81] and men with indoor work had a high SIR of 1·09 (95% CI 1·07-1·11). Differences in women pointed in the same direction. High socioeconomic status was associated with an excess risk: SIR 1·34 (95% CI 1·28-1·40) in men and SIR 1·31 (95% CI 1·26-1·36) in women. Technical, transport, military and public safety workers with potential skin exposure to carcinogens had excess risks. CONCLUSIONS: Occupational variation in CM risk may be partly explained by host, socioeconomic and skin exposure factors. Differences in CM risk across socioeconomic groups attenuated slightly over time.

Reintervention or mortality within 90 days of bariatric surgery: population-based cohort study.

BACKGROUND: Bariatric surgery carries a risk of severe postoperative complications, sometimes leading to reinterventions or even death. The incidence and risk factors for reintervention and death within 90 days after bariatric surgery are unclear, and were examined in this study. METHODS: This population-based cohort study included all patients who underwent bariatric surgery in one of the five Nordic countries between 1980 and 2012. Data on surgical and endoscopic procedures, diagnoses and mortality were retrieved from national high-quality and complete registries. Multivariable Cox regression analysis was used to calculate hazard ratios (HRs), adjusted for country, age, sex, co-morbidity, type of surgery and approach, year and hospital volume of bariatric surgery. RESULTS: Of 49 977 patients, 1111 (2·2 per cent) had a reintervention and 95 (0·2 per cent) died within 90 days of bariatric surgery. Risk factors for the composite outcome reintervention/mortality were older age (HR 1·65, 95 per cent c.i. 1·36 to 2·01, for age at least 50 years versus less than 30 years) and co-morbidity (HR 2·66, 1·53 to 4·62, for Charlson co-morbidity index score 2 or more versus 0). The risk of reintervention/mortality was decreased for vertical banded gastroplasty compared with gastric bypass (HR 0·37, 0·28 to 0·48) and more recent surgery (HR 0·51, 0·39 to 0·67, for procedures undertaken in 2010 or later versus before 2000). Sex, surgical approach (laparoscopic versus open) and hospital volume did not influence risk of reintervention/mortality, but laparoscopic surgery was associated with a lower risk of 90-day mortality (HR 0·29, 0·16 to 0·53). CONCLUSION: Reintervention and death were uncommon events within 90 days of bariatric surgery even in this unselected nationwide cohort from five countries. Older patients with co-morbidities have an increased relative risk of these outcomes.

ANTECEDENTES: La cirugía bariátrica conlleva un riesgo de complicaciones postoperatorias graves, que algunas veces ocasionan reintervenciones o incluso son causa de mortalidad. La incidencia y los factores de riesgo de reinterveniones y mortalidad a los 90 días tras cirugía bariátrica no están claros, y fueron examinados en este estudio. MÉTODOS: Todos los pacientes que fueron sometidos a cirugía bariátrica en uno de los cinco países nórdicos en 1980-2012 fueron incluidos en un estudio de cohortes de base poblacional. Los datos de los procedimientos quirúrgicos y endoscópicos, diagnóstico, y mortalidad se obtuvieron a partir de registros nacionales completos y de alta calidad. Mediante una regresión de Cox multivariable se obtuvieron los cocientes de riesgos instantáneos (hazard ratios, HR) y los intervalos de confianza 95% (i.c. del 95%) ajustados por país, edad, sexo, comorbilidad, y tipo, abordaje, año y volumen de casos de cirugía bariátrica del hospital. RESULTADOS: De un total de 49.977 pacientes, 1.111 (2,2%) precisaron una reintervención y 95 (0,2%) fallecieron durante los primeros 90 días tras la cirugía bariátrica. Los factores de riesgo para el resultado compuesto reintervención/mortalidad fueron la edad avanzada (HR = 1,7 (i.c. del 95% 1,4-2,0) edad ≥ 50 versus < 30 años)) y la comorbilidad (HR = 2,7 (i.c. del 95% 1,5-4,6) puntuación del índice de comorbilidad de Charlson ≥ 2 versus 0)). Se observó una disminución de los HRs tras la gastroplastia vertical con banda en comparación con el bypass gástrico (HR = 0,4, (i.c. del 95% 0,3-0,5)) y el periodo de estudio más reciente (HR = 0,5 (i.c. del 95% 0,4-0,7) ≥ 2010 versus < 2000)). El sexo, el abordaje quirúrgico laparoscópico versus abierto y el volumen del hospital no influyeron sobre el riesgo de reintervención/mortalidad, pero la cirugía laparoscópica se asoció con una mortalidad a los 90 días más baja (HR 0,3, i.c. del 95% 0,2-0,5). CONCLUSIÓN: La reintervención y la mortalidad son eventos infrecuentes durante los primeros 90 días tras la cirugía bariátrica, incluso en esta cohorte nacional y no seleccionada de cinco paises. Los pacientes mayores con comorbilidades tienen un riesgo relativo aumentado de reintervención y mortalidad.

Conservative management of women with cervical intraepithelial neoplasia grade 2 in Denmark: a cohort study.

OBJECTIVE: Assess the progression, persistence, and regression of cervical intraepithelial neoplasia grade 2 (CIN2) after new guidelines on conservative treatment, compared with previous practice. DESIGN: Nationwide register-based cohort study. SETTING: Denmark. POPULATION: Women aged 18-44 years diagnosed with CIN2 on biopsy: 6721 in 2008-2011 and 6399 in 2014-2017. METHODS: Register data were retrieved from before (2008-2011) and after (2014-2017) the introduction of new guidelines. Histology diagnoses at second visit were used to assess progression (CIN3+), persistence (CIN2), or regression (CIN1/normal). MAIN OUTCOME MEASURES: Proportion of CIN2 by type of management. Relative risk (RR) and corresponding 95% confidence intervals (95% CIs) for progression, persistence, and regression at second visit in 2014-2017, versus 2008-2011. RESULTS: The proportion of CIN2 managed conservatively increased from 29.6% in 2008-2011 to 53.3% in 2014-2017 (RR 1.81, 95% CI 1.73-1.89). Time to second visit increased by 2 months. Regression increased from 23.5 to 30.2% (RR 1.29, 95% CI 1.22-1.36), whereas persistence and progression decreased, from 42.6 to 34.9% (RR 0.82, 95% CI 0.78-0.86) and from 28.0 to 22.8% (RR 0.81, 95% CI 0.77-0.86), respectively. In 2008-2011, women managed conservatively had a regression rate of 41.8%, persistence rate of 40.9%, and progression rate of 16.6%. In 2014-2017, these rates were 46.7, 35.5, and 17.1%, respectively. CONCLUSION: After implementation of the new guidelines, conservative management became more frequent, and is now used for more than half of women with CIN2. Lesion regression became more frequent, now experienced by 47% of women managed conservatively. Similar regression rates were seen in women younger and older than 30 years, suggesting that conservative management is justifiable for women of childbearing age. TWEETABLE ABSTRACT: In Denmark, more than half of women with CIN2 are managed conservatively, and half of these women experience lesion regression.

High-grade cervical intraepithelial neoplasia in human papillomavirus self-sampling of screening non-attenders.

BACKGROUND: Self-sampling for human papillomavirus (HPV) offered to women who do not participate in cervical cancer screening is an increasingly popular method to increase screening coverage. The rationale behind self-sampling is that unscreened women harbour a high proportion of undetected precancer lesions. Here, we compare the cervical intraepithelial neoplasia grade 2 or worse (⩾CIN2) detection rate between non-attenders who participated in self-sampling and women attending routine screening. METHODS: A total of 23 632 women who were qualified as non-attenders in the Copenhagen Region were invited for HPV-based self-sampling. Of these, 4824 women returned a self-sample, and HPV-positive women were referred for cytology and HPV co-testing as follow-up. The entire cohort and a reference cohort (3347 routinely screened women) were followed for histopathology confirmed ⩾CIN2. Odds ratio (OR) and the relative positive predictive value of ⩾CIN2 detection between the two populations were estimated. RESULTS: Women participating in self-sampling had a higher ⩾CIN2 detection than women undergoing routine cytology-based screening (OR=1.83, 95% CI: 1.21-2.77) and a similar detection as routinely screened women tested with cytology and HPV testing (OR=1.03, 95% CI: 0.75-1.40). The positive predictive value for ⩾CIN2 was higher in screening non-attenders than in routinely HPV- and cytology-screened screened women (36.5% vs 25.6%, respectively). CONCLUSIONS: Self-sampling offered to non-attenders showed higher detection rates for ⩾CIN2 than routine cytology-based screening, and similar detection rates as HPV and cytology co-testing. This reinforces the importance of self-sampling for screening non-attenders in organised cervical cancer screening.

Prevalence of Human Papillomavirus in Self-Taken Samples from Screening Nonattenders.

The Copenhagen Self-Sampling Initiative (CSi) has shown how human papillomavirus (HPV)-based self-sampling can be used to increase screening participation among 23,632 nonattenders in the Capital Region of Denmark. In this study, we describe HPV prevalence and genotype frequency in 4,824 self-samples as determined by three HPV assays (the CLART, Onclarity, and Hybrid Capture 2 [HC2] assays) and compare the results with those for physician-taken follow-up samples. The HPV self-sample findings were also compared to the findings for a reference population of 3,347 routinely screened women from the Horizon study, which had been undertaken in the same screening laboratory. Nonattenders had an HPV prevalence of 11.3% as determined by the CLART assay, which was lower than that for women from the Horizon study (18.5%). One-third of the CSi women who tested HPV positive by self-sampling tested HPV negative on the physician-taken follow-up sample. The CLART and Onclarity assays agreed on 64% (95% confidence interval [CI], 60 to 68%) of the HPV-positive self-taken samples. When the HC2 assay results were added into a three-way comparison, the level of agreement decreased to 27% (95% CI, 24 to 29%). Our findings suggest that further validation of HPV assays on self-taken samples is needed for optimal HPV detection and correct clinical management of HPV-positive women.

Referral population studies underestimate differences between human papillomavirus assays in primary cervical screening.

OBJECTIVE: We studied how representative cytologically abnormal women ("referral populations") are with respect to uncovering differences between human papillomavirus (HPV) assays in the primary screening where most women are cytologically normal. METHODS: A total of 4997 women were tested with SurePath® cytology, and Hybrid Capture 2 (HC2), cobas, CLART and APTIMA HPV assays. Women with positive test results were offered a follow-up. For all detected HPV infections and HPV-positive high-grade cervical intraepithelial neoplasia (≥CIN2), we studied the distributions of assay-specific signal strengths in the baseline samples as documented by the assays' automatically generated reports. We calculated the likelihood of test result discordance as the proportion of HPV-positive samples that were not confirmed by all four assays. RESULTS: Median signal strengths for HPV infections were weaker in normal than abnormal cytology (P<.001, adjusted for women's age, multiple infections and the reason for taking the sample). For HC2, they were RLU/CO 11.0 (interquartile range, IQR: 3.3-52.8) vs 124.2 (IQR: 22.8-506.9), respectively; for cobas, Ct 33.5 (IQR: 29.6-37.5) vs 26.9 (IQR: 23.7-31.3), respectively; for APTIMA, S/CO 10.2 (IQR: 5.8-11.3) vs 11.1 (IQR: 9.4-15.5), respectively. Similar patterns were observed for HPV-positive ≥CIN2. The four HPV assays more frequently returned discordant test results in normal than in abnormal cytology. Relative frequency of discordance in detecting HPV infections was 0.39 (95% confidence interval: 0.33-0.48) for abnormal vs normal cytology. CONCLUSIONS: These data suggest that referral population studies, by not including sufficient numbers of cytology normal women, underestimate the differences between HPV assays that would become apparent in primary screening.

Impact of technology on cytology outcome in cervical cancer screening of young and older women.

Little is known about age-dependent variation in outcomes of cervical cytology with modern technologies. This population-based study evaluated age-dependent changes after routine implementation of ThinPrep and SurePath technology in two independent laboratories, and controlled for time trends in a third laboratory using manually read conventional cytology continually. Data were collected from the Danish National Health Care Registers. For each laboratory, we compared proportions of abnormal cytology defined as atypical squamous cells of undetermined significance or worse (ASCUS+) by age and technology phase. The study included 489,960 cytological samples with no recent abnormality from women aged 23-59 years, routinely screened between 1998 and 2007. Implementation of SurePath liquid-based cytology (LBC) was followed by an increase in abnormal cytology in women aged 23-29 years from 4.6 to 6.1%, relative proportion (RP): 1.31 [95% confidence interval (CI): 1.08-1.61], and a decrease in women aged 45-59 years from 2.9 to 2.0%, RP: 0.71 (95% CI: 0.60-0.83). Implementation of ThinPrep LBC was followed by a decrease in abnormal cytology both in women aged 23-29 years from 7.7 to 6.8%, RP: 0.89 (95% CI: 0.78-1.02) and in women aged 45-59 years from 3.4 to 1.0%, RP: 0.30 (95% CI: 0.24-0.37). With implementation of imaging-assisted reading, regardless of the brand of technology, the proportion of abnormality increased by around 30% in all age groups (range from 19 to 41%). In the laboratory with unchanged technology no trends in abnormality proportions were observed. The impact of LBC implementation on cytological abnormality proportions varied considerably across age groups.

Occupation and risk of primary fallopian tube carcinoma in Nordic countries.

The aetiology of primary Fallopian tube carcinoma (PFTC) is poorly understood. Occupational exposures may contribute to PFTC risk. We studied incidence of PFTC in occupational categories in the Nordic female population aged 30-64 years during the 1960, 1970, 1980/1981 and/or 1990 censuses in Denmark, Finland, Iceland, Norway and Sweden. Standardized incidence ratios (SIRs) for the years following inclusion in the study up to 2005 were calculated for 53 occupations; the expected numbers of cases were based on PFTC incidence in the national populations. Altogether 2,206 PFTC cases were detected during follow up via data linkages with the Nordic cancer registries. Significantly increased risks of PFTC were observed for smelting workers (SIR 3.99, 95% confidence interval 1.46-8.68, Obs = 6), artistic workers (2.64, 1.44-4.43, Obs = 14), hairdressers (2.18, 1.41-3.22, Obs = 25), packers (1.62, 1.11-2.29, Obs = 32), nurses (1.49, 1.14-1.92, Obs = 60), shop workers (1.25, 1.07-1.46, Obs = 159) and clerical workers (1.20, 1.07-1.35, Obs = 271) and these sustained over times and different Nordic countries. There was a nonsignificant increased risk for PFTC among welders, printers, painters and chemical process workers. The risk was significantly and consistently low for women working in farming (0.68, 0.47-0.95, Obs = 34) and among economically inactive women (0.88, 0.82-0.94, Obs = 833). The possible role of occupational exposures to the PFTC risks found in this study must be further evaluated in studies with a possibility to adjust for possible confounding factors, such as reproductive and life-style factors, which was not possible in our study.

What women want. Women's preferences for the management of low-grade abnormal cervical screening tests: a systematic review.

BACKGROUND: If human papillomavirus (HPV) testing will replace cytology in primary cervical screening, the frequency of low-grade abnormal screening tests will double. Several available alternatives for the follow-up of low-grade abnormal screening tests have similar outcomes. In this situation, women's preferences have been proposed as a guide for management decisions. OBJECTIVES: To determine women's preferences for the follow-up of low-grade cervical screening abnormalities. SEARCH STRATEGY: Using Medical Subject Headings (MeSH) terms, PubMed was searched for articles published up to December 2010. The reference lists of the retrieved studies were consulted. SELECTION CRITERIA: Studies asking women to state a preference between active follow-up and observation for the management of low-grade abnormalities on screening cytology or HPV tests. DATA COLLECTION AND ANALYSIS: Information on study design, participants and outcomes was retrieved using a prespecified form. Studies were sorted by design. MAIN RESULTS: Thirteen studies were included in the review. In all five studies that surveyed women with abnormal tests before any management had started, two-thirds preferred active follow-up, predominantly as immediate colposcopy, to observation, predominantly as repeated Pap smears. In all but two studies testing other situations, women more often expressed a preference for active follow-up than for observation; however, women appeared to be somewhat more willing to accept observation if reassured of the low risk of cervical cancer. CONCLUSIONS: Even for low-grade abnormal cervical tests, women tend to prefer active management strategies. It may be a challenge to meet their expectations of optimal follow-up when HPV testing is used in primary screening.

Incomplete follow-up of positive HPV tests: overview of randomised controlled trials on primary cervical screening.

BACKGROUND: It has been suggested that adjustment for incomplete compliance with follow-up in women with positive human papillomavirus (HPV) tests would be appropriate for estimating the true sensitivity of cervical screening with HPV testing. We assessed the compliance and its impact on > or =CIN3 detection in all eight randomised controlled trials (RCT) with published baseline-round data. METHODS: We extracted data on recommended follow-up procedures, follow-up compliance, and > or =CIN3 detection for both arms of each RCT, and assessed their correlation. RESULTS: Compliance with a direct referral for colposcopy was around 90% in all RCTs, whereas compliance with repeated testing among HPV-positive/cytology-negative women was around 60% in three RCTs and 73% in one RCT. Detection of > or =CIN3 was significantly increased in two out of six RCTs with reported data. The correlation between compliance with follow-up in HPV-positive women and relative > or =CIN3 detection was 0.48 (P=0.33). CONCLUSION: There is at present scant evidence to support the view that the measured sensitivity of HPV screening is a simple reflection of compliance with follow-up. Adjustment of measured cervical intraepithelial neoplasia detection on the basis of compliance data may not always be justifiable, and if adjustment is made, it should be used very judiciously.

Breast density and outcome of mammography screening: a cohort study.

The purpose of this study was to investigate the effect of breast density on breast cancer (BC) mortality in a mammography screening programme. The cohort included 48 052 women participating in mammography screening in Copenhagen, Denmark, where biennial screening is offered to women aged 50-69 years. We collected information for the years 1991-2001 on screening outcome, incident BCs (screen-, interval-, and later detected), and BC deaths. Breast density was dichotomised into fatty (F) and mixed/dense (M/D) breasts. Screening sensitivity was measured as the odds ratio of interval versus screen-detected cancer for dense versus F breasts. Poisson regression was used to estimate the ratios for BC incidence, case fatality, and mortality between women with M/D and F breasts. For women with M/D breasts, the odds ratio of an interval cancer was 1.62 (95% confidence interval, CI, 1.14-2.30), and the age-adjusted rate ratios were 2.45 (95% CI 2.14-2.81) for BC incidence, 0.60 (95% CI 0.43-0.84) for case fatality, and 1.78 (95% CI 1.17-2.72) for BC mortality. The study shows that BC in women with M/D breasts is more frequent, but on average less severe, than in women with F breasts.

Dietary risk factors for inflammatory bowel diseases in a high-risk population: Results from the Faroese IBD study.

Background: The Faroe Islands currently have the highest recorded inflammatory bowel disease (IBD) incidence in the world. Objective: This study investigated environmental risk factors for IBD in the Faroese population. Methods: Environmental exposure data including lifestyle risk factors and neurotoxicants collected for over 30 years were retrieved from the Children's Health and the Environment in the Faroes (CHEF) cohorts including mainly mother-child pairs, with exposure data collected from pregnant mothers. For lifestyle risk factors, the incidence of IBD and ulcerative colitis (UC) was calculated as the rate ratio (RR) with 95% confidence intervals (CI) in exposed versus non-exposed persons. For neurotoxicants RR was calculated for persons with high versus low exposure. Results: Six cohorts included 5698 persons with complete follow-up data and at least one exposure, and 37 were diagnosed with IBD. For pilot whale/blubber, the RR was 1.02 (95% CI, 0.48-2.18); RR of 1.01 for fish (95% CI, 0.35-2.91); and of the pollutants studied, a statistical significantly increased risk was found for 1,1,1,-trichloro-2,2-bis-(p-chlorophenyl) ethane (p,p'-DDT); RR 3.04 (95% CI, 1.12-8.30). RRs were 1.96 (95% CI, 1.03-3.73) for smoking and 1.10 (95% CI, 0.55-2.19) for alcohol intake. Conclusion: The high IBD incidence is unlikely to be caused by special dietary habits or by environmental pollutants.

Complexities in the estimation of overdiagnosis in breast cancer screening.

There is interest in estimating and attributing temporal changes in incidence of breast cancer in relation to the initiation of screening programmes, in particular to estimation of overdiagnosis of breast cancer as a result of screening. In this paper, we show how screening introduces complexities of analysis and interpretation of incidence data. For example, lead time brings forward time- and age-related increases in incidence. In addition, risk factors such as hormone replacement therapy use have been changing contemporaneously with the introduction of screening. Although we do not indicate exactly how such complexities should be corrected for, we use some simple informal adjustments to show how they may account for a substantial proportion of increased incidence, which might otherwise erroneously have been attributed to overdiagnosis. We illustrate this using an example of analysis of breast cancer incidence data from Sweden.

The incidence of inflammatory bowel disease in Denmark 1980-2013: a nationwide cohort study.

BACKGROUND: Globally, the incidence rates of inflammatory bowel disease (IBD) are increasing; however, data from high-incidence areas are conflicting. Previous studies in Denmark have assessed incidence rates of Crohn's disease (CD) and ulcerative colitis (UC) using short observation periods. AIM: To investigate trends in IBD incidence in Denmark over a thirty-year period using nationwide data. METHODS: Patients diagnosed with CD or UC in Denmark between 1980 and 2013 were identified in the Danish National Patient Registry (NPR) and included in a nationwide cohort. Incidence rates estimated using different numbers of National Patient Registry records (≥1, 2, 3 or 4) required for case definition were compared. RESULTS: From 1980 to 2013 the incidence of CD increased from 5.2 (95% CI: 5.0-5.4) per 100 000 to 9.1 (95% CI: 8.7-9.5) per 100 000 and the incidence of UC increased from 10.7 (95% CI: 10.4-11.0) per 100 000 to 18.6 (95% CI: 18.0-19.2) per 100 000. The increased incidence in CD and UC was independent of gender. The annual increase in incidence rate was greatest in patients aged <15 years for CD and those older than 15 years for UC. For both CD and UC the incidence rates for females were significantly higher than for males. The number of registry records chosen to define IBD cases greatly influenced incidence estimates. CONCLUSIONS: The incidence of IBD in Denmark continues to increase and is among the highest in the world. Using at ≥2 records of IBD diagnosis in the Danish National Patient Registry will result in more valid incidence estimates.

Inflammatory bowel diseases in Faroese-born Danish residents and their offspring: further evidence of the dominant role of environmental factors in IBD development.

BACKGROUND: The incidence of inflammatory bowel disease (IBD) is record high in the Faroe Islands, and many Faroese emigrate to Denmark, where the IBD incidence is considerably lower. AIM: To study the IBD incidence in first-, second- and third-generation immigrants from the Faroe Islands to Denmark to assess the extent to which the immigrants adopt the lower IBD incidence of their new home country. METHODS: Data on Faroese-born Danish residents and their children were retrieved from the Danish Central Population Register for 1980-2014. Incident IBD cases were identified from the Danish National Patient Register. Standardised Incidence Ratios (SIRs) were used to compare the IBD risk in immigrants with that of Danes. 95% confidence intervals (CI) were calculated using the square-root transform. RESULTS: First-generation Faroese immigrants had a higher IBD incidence than Danes, SIR 1.25 (95% CI, 0.97-1.59) for men and 1.28 (95% CI, 1.05-1.53) for women. This excess risk derived from ulcerative colitis (UC), SIR 1.44 (95% CI, 1.10-1.87) for men and 1.36 (95% CI, 1.09-1.68) for women. No excess risk was found for Crohn's disease (CD). The UC risk was nearly doubled during the immigrants' first 10 years in Denmark; SIR 2.13 (95% CI, 1.52-2.92) for men and 1.63 (95% CI, 1.19-2.18) for women. CONCLUSIONS: Although some impact of genetic dilution cannot be excluded, our findings indicate importance of gene-environment interplay in UC, as the excess UC risk in Faroese immigrants to Denmark disappeared over time and over one generation in men and over two generations in women.

Silica dust and lung cancer: results from the Nordic occupational mortality and cancer incidence registers.

Autopsy studies of the relationship between silicosis and lung cancer have been mainly negative; but recent epidemiologic studies have indicated a positive association, and an excess lung cancer risk has been observed in some occupational groups with exposure to silica dust. For the further shedding of light on the possible association between silica dust and lung cancer, analysis was made on mortality and cancer incidence data available in census-based record linkage studies from the Nordic countries for males in occupational groups with potential exposure to silica dust. The study showed an excess lung cancer risk for foundry workers in all the Nordic countries and for miners in Sweden. These results were consistent with findings from previous in-depth epidemiologic studies. The lung cancer risk did not differ significantly from that of the respective national populations for males working in excavation; stone quarries; sand and gravel pits; and glass, porcelain, ceramic, and tile manufacture. Stonecutters, who are probably not exposed to known lung carcinogens at the workplace but in some places to high concentrations of silica dust, showed a significant excess lung cancer risk in both Finland and Denmark. Excess lung cancer risks furthermore were seen for Finish miners, for Finnish males in excavation work, and for Danish glassworkers.

Effect of organized screening on incidence and mortality of cervical cancer in Denmark.

Pap smears were used only on a limited scale in Denmark until the late 1960s. Since then smears have been taken both in organized screening programs and outside the programs by general practitioners, private gynecologists, and hospital wards. The present smear-taking activity is equivalent to an average of one smear every second year per woman. As the responsibility for health care rests with the counties in Denmark, differences are found between the counties both concerning organization of screening programs, and concerning the overall level of the smear-taking activity. An analysis using multiplicative Poisson models on county-based incidence and mortality data for women aged 30-59 years in 1963-1982 showed a statistically significant effect of organized screening in reducing both the incidence (RR = 0.67; 95% CI, 0.61-0.73), and the mortality (RR = 0.68; 95% CI, 0.59-0.78) of cervical cancer from 5 years after introduction of an organized screening program. The level of overall smear-taking activity was found to be of limited importance when organized screening was taken into account.

Tumour size distribution in mammography screening.

Many mammography screening programmes have not been able to show higher percentages of small invasive cancers detected at subsequent screens than at initial screens. This has been a matter of serious concern as it contradicts the very theory of screening. Based on data from the county of Fyn, Denmark we evaluated the distribution based on point estimates, as well as on the entire tumour size distribution. The programme changed the amount of tumours less than 15 or 20 mm, but did not change the amount of tumours less than 10 mm. We evaluated the entire tumour size distribution and found that screen number was the only significant factor, implying that the number of screens changed the tumour size distribution. We recommend that the entire tumour size distribution is used to evaluate the ability of a programme to detect small breast cancers, instead of only point estimates as has previously been the practice.