Spillover improved survival in non-invited patients of the colorectal cancer screening programme

Objectives

In colorectal cancer screening, randomized clinical trials have shown a 16% mean reduction in colorectal cancer mortality, but the Finnish randomized health services study showed no effect. We quantified spillover (the total indirect effect caused by the programme on the non-invited) and corrected the effectiveness estimate of the Finnish programme.

Methods

We retrieved from the Finnish Cancer Registry data on all non-invited colorectal cancer patients diagnosed in 1999–2013 in municipalities that adopted screening ( n = 18,948). Patients were stratified by three 5-year diagnostic periods and two calendar periods of programme adoption in the municipality of residence. Follow-up ended on 31 December 2013. We measured the spillover effect in patient survival, based on differences of adjusted estimates of the colorectal cancer-related hazard of death between pairs of consecutive diagnostic periods.

Results

The spillover effect was estimated as 9 percentage points (95% confidence interval: −1 to 19 percentage points). It was 13 percentage points in men (−1 to 26 percentage points) and 5 percentage points in women (−9 to 20 percentage points). The corrected effect estimate of implementing screening in Finland was 5 percentage points.

Conclusions

The corrected Finnish effectiveness estimate was consistent with estimates from randomized trials. Indirect effects (spillover) bias the invitee–control contrast. In this case, spillover was an inherent benefit of the Finnish programme.

Cumulative risk of false positive test in relation to breast symptoms in mammography screening: a historical prospective cohort study

Mammography has been found effective as the primary screening test for breast cancer. We estimated the cumulative probability of false positive screening test results with respect to symptom history reported at screen. A historical prospective cohort study was done using individual screening data from 413,611 women aged 50-69 years with 2,627,256 invitations for mammography screening between 1992 and 2012 in Finland. Symptoms (lump, retraction, and secretion) were reported at 56,805 visits, and 48,873 visits resulted in a false positive mammography result. Generalized linear models were used to estimate the probability of at least one false positive test and true positive at screening visits. The estimates were compared among women with and without symptoms history. The estimated cumulative probabilities were 18 and 6 % for false positive and true positive results, respectively. In women with a history of a lump, the cumulative probabilities of false positive test and true positive were 45 and 16 %, respectively, compared to 17 and 5 % with no reported lump. In women with a history of any given symptom, the cumulative probabilities of false positive test and true positive were 38 and 13 %, respectively. Likewise, women with a history of a 'lump and retraction' had the cumulative false positive probability of 56 %. The study showed higher cumulative risk of false positive tests and more cancers detected in women who reported symptoms compared to women who did not report symptoms at screen. The risk varies substantially, depending on symptom types and characteristics. Information on breast symptoms influences the balance of absolute benefits and harms of screening.

Parity and mortality in cases of childhood-onset diabetes mellitus

AIMS

This study aims to assess the association between parity and mortality in adults with childhood-onset type 1 diabetes (T1D) and their matched controls.

METHODS

Individual data (308 617 person-years) on mortality and the reproductive histories of a Finnish cohort of 2307 women and 2819 men with T1D, each with two matched controls, were obtained from the National Population Register. All persons with diabetes had been diagnosed with T1D in 1965-1979 at the age of 17 or under.

RESULTS

All-cause mortality in people without offspring was significantly higher than that in people with children among both people with diabetes and non-diabetic control persons in both sexes (all p-values <0.01). In men with offspring, the decrease of mortality rate compared with men without offspring was less marked among those with diabetes (9% reduction in mortality hazard ratio (HR) with one offspring, 47% with two) than among those without diabetes (33% HR (p = 0.025) and 61% HR (p = 0.023) reduction, respectively). In women with offspring, the association between parity and mortality was independent of diabetes status. Having at least two offspring was associated with a decreased hazard of diabetes-related death regardless of sex; among women with diabetes, even having one offspring was associated with a decreased hazard of dying from diabetes (HR = 0.46; 95% CI 0.31, 0.69).

CONCLUSIONS

The association between parity and mortality follows different patterns in men and women with T1D. To what extent this reflects effects of health on family planning decisions in people with T1D cannot be defined without further studies. Copyright © 2016 John Wiley & Sons, Ltd.

Proportion of women with self-reported opportunistic mammography before organized screening

BACKGROUND

In Finland, organized nationwide breast cancer (BC) screening is biennially offered for women aged 50-69 years. The aim was to estimate, for the first time in Finland, the proportion of women having opportunistic mammography at age less than 50 years and to investigate the role of BC family history and educational level for having opportunistic mammography.

MATERIAL AND METHODS

The study material comprises two self-administered, population-based questionnaires from altogether 9845 healthy women; 4666 women in Women's Health and Use of Hormone-study (WHH survey), and 5179 in Breast Cancer Screening, Lifestyle and Quality of Life-study (EET survey). We report the estimated proportions of women with self-reported opportunistic mammography at age <50 years in percentages.

RESULTS

The response percentages were 53% in the WHH survey and 52% in the EET survey. The percentage of women with self-reported opportunistic mammography was 66.7% and 60.4% in the two questionnaires, respectively. Regarding family history of BC, 76.5% and 68.5% of women with BC family history in a first degree relative reported having had a mammography, in contrast to that of 65.5% and 59.4% of women without BC family history. Opportunistic mammography was also more common in women with >12 years of education than women with ≤12 years of education.

DISCUSSION AND CONCLUSIONS

Overall, some two thirds of the women reports of having had a mammography before organized screening started. Opportunistic mammography was more likely among women with a positive family history of BC in a first degree relative as well as more than 12 years of education. Regardless of low response activity, the observed popularity of opportunistic mammography before organized screening gives ground for further evaluation of the related health care practices. Screening activity before organized screening also influences the evaluation of the screening program, as women have different, indeterminate histories of pre-organized screening.

Coverage and accuracy of myeloproliferative and myelodysplastic neoplasms in the Finnish Cancer Registry

Background Registration of haematological malignancies presents specific challenges, and a wide range of data is required to ensure case ascertainment and proper classification of these diseases. We studied the data quality of myeloproliferative and myelodysplastic neoplasms in the Finnish Cancer Registry (FCR), comparing information with hospital discharges. Material and methods Hospital discharges (HILMO) in 2007-2013 including diagnostic codes of myeloproliferative and myelodysplastic neoplasms were extracted. Patients were individually linked to the FCR database for all haematological malignancies registered in 1953-2013. Coverage and accuracy of the FCR and agreement between registers was estimated. Results In total 5289 individuals were retrieved from two registers. Of these, 1406 were common, 1080 only found in the FCR and 2803 only in the HILMO. Coverage of myeloproliferative and myelodysplastic neoplasms in the FCR was 47.0% (95% CI 45.7-48.4%). Almost one quarter of the registrations in the FCR was based on a death certificate only. The accuracy of diagnosis was 51.4% (95% CI 49.4-53.3%), but it varied substantially by disease category. Kappa statistic for agreement between registers was excellent (0.83, 95% CI 0.80-0.85) for common cases. 7.6% of cases in the HILMO was registered as leukaemias in the FCR. Conclusions More than half of the patients found in the HILMO were entirely missing from the FCR. However, some of the diagnoses in HILMO may be preliminary and this represents the maximal number of missing cases. Cancer registers benefit from supplementary data sources, such as hospital discharges, to increase coverage and accuracy of register data on haematological malignancies.

Genome-wide time-to-event analysis on smoking progression stages in a family-based study

BACKGROUND

Various pivotal stages in smoking behavior can be identified, including initiation, conversion from experimenting to established use, development of tolerance, and cessation. Previous studies have shown high heritability for age of smoking initiation and cessation; however, time-to-event genome-wide association studies aiming to identify underpinning genes that accelerate or delay these transitions are missing to date.

METHODS

We investigated which single nucleotide polymorphisms (SNPs) across the whole genome contribute to the hazard ratio of transition between different stages of smoking behavior by performing time-to-event analyses within a large Finnish twin family cohort (N = 1962), and further conducted mediation analyses of plausible intermediate traits for significant SNPs.

RESULTS

Genome-wide significant signals were detected for three of the four transitions: (1) for smoking cessation on 10p14 (P = 4.47e-08 for rs72779075 flanked by RP11-575N15 and GATA3), (2) for tolerance on 11p13 (P = 1.29e-08 for rs11031684 in RP1-65P5.1), mediated by smoking quantity, and on 9q34.12 (P = 3.81e-08 for rs2304808 in FUBP3), independent of smoking quantity, and (3) for smoking initiation on 19q13.33 (P = 3.37e-08 for rs73050610 flanked by TRPM4 and SLC6A16) in analysis adjusted for first time sensations. Although our top SNPs did not replicate, another SNP in the TRPM4-SLC6A16 gene region showed statistically significant association after region-based multiple testing correction in an independent Australian twin family sample.

CONCLUSION

Our results suggest that the functional effect of the TRPM4-SLC6A16 gene region deserves further investigation, and that complex neurotransmitter networks including dopamine and glutamate may play a critical role in smoking initiation. Moreover, comparison of these results implies that genetic contributions to the complex smoking behavioral phenotypes vary among the transitions.

Probiotics and respiratory and gastrointestinal tract infections in Finnish military conscripts - a randomised placebo-controlled double-blinded study

Military conscripts are susceptible to respiratory and gastrointestinal tract infections. In previous studies probiotics have shown potency to reduce upper respiratory and gastrointestinal infections. The aim was to study whether probiotic intervention has an impact on seasonal occurrence of upper respiratory and gastrointestinal infections in two different conscript groups. In a randomised, double-blinded, placebo controlled study (https://clinicaltrials.gov NCT01651195), a total of 983 healthy adults were enrolled from two intakes of conscripts. Conscripts were randomised to receive either a probiotic combination of Lactobacillus rhamnosus GG (LGG) and Bifidobacterium animalis ssp. lactis BB12 (BB12) or a control chewing tablet twice daily for 150 days (recruits) or for 90 days (reserve officer candidates). Clinical examinations were carried out and daily symptom diaries were collected. Outcome measures were the number of days with respiratory and gastrointestinal symptoms and symptom incidence, number and duration of infection episodes, number of antibiotic treatments received and number of days out of service because of the infection. Statistically no significant differences were found between the intervention groups either in the risk of symptom incidence or duration. However, probiotic intervention was associated with reduction of specific respiratory infection symptoms in military recruits, but not in reserve officer candidates. Probiotics did not significantly reduce overall respiratory and gastrointestinal infection morbidity.

Cause and manner of death and phase of the blood alcohol curve

In a large number of forensic autopsies (N = 28,184) the concentrations of ethanol in femoral blood and bladder urine were determined and the urine-to-blood concentration ratios of ethanol were calculated. Based on the differences in ethanol concentration between urine and blood, the deaths were classified as having occurred during the absorptive, the peak or the post-absorptive phase of the blood–alcohol curve. Most people died in the post-absorptive phase, N = 24,223 (86%), whereas 1538 individuals (5.5%) were still absorbing alcohol and 2423 (8.6%) were at or close to the peak BAC at time of death. Both blood–alcohol concentration (BAC) and urine–alcohol concentration (UAC) were significantly higher in the post-absorptive phase (p < 0.001). The proportions of people dying in the absorptive and peak phases increased with advancing age. The cause of death (CoD) and manner of death (MoD) according to death certificates were compared with phase of the blood–alcohol curve using a multinomial regression model with and without making adjustment for possible effects of age, gender and BAC. The relative risk (RR) and relative risk ratios (RRR) showed some associations between CoD and phase of the blood–alcohol curve. Undetermined MoD was significantly higher in the absorptive phase compared with the post-absorptive phase (RRR = 2.12). Deaths related to esophagus, stomach and duodenum (RRR = 2.04) and alcoholic liver diseases (RRR = 1.85) were significantly higher at or close to peak phase compared to the post-absorptive phase. Road-traffic fatalities were more prevalent in the peak BAC phase (RRR = 1.33) and deaths by accidental falls were less in the absorptive phase (RRR = 0.58) compared with the post-absorptive phase. The phase of alcohol intoxication seems relevant to consider by forensic experts when alcohol-related deaths are investigated.

Distinctive Cancer Associations in Patients With Neurofibromatosis Type 1

PURPOSE

The current study was designed to determine the risk of cancer in patients with neurofibromatosis type 1 (NF1) by cancer type, age, and sex with unprecedented accuracy to be achieved by combining two total population-based registers.

PATIENTS AND METHODS

A population-based series of patients with NF1 (N = 1,404; 19,076 person-years) was linked to incident cancers recorded in the Finnish Cancer Registry and deaths recorded in the national Population Register Centre between 1987 and 2012. Standardized incidence ratios (SIRs) and standardized mortality ratios (SMRs) were calculated for selected cancer types. Survival of the patients with cancer with and without NF1 was compared.

RESULTS

In malignant peripheral nerve sheath tumors and CNS tumors, the cancers traditionally associated with NF1, we observed SIRs of 2,056 (95% CI, 1,561 to 2,658), and 37.5 (95% CI, 30.2 to 46.0), respectively, and SMRs of 2,301 (95% CI, 1,652 to 3,122) and 30.2 (95% CI, 19.1 to 45.2), respectively. We found an unequivocally increased risk for breast cancer. In particular, SIR was 11.1 (95% CI, 5.56 to 19.5) for breast cancer in women with NF1 age < 40 years; the overall SMR for breast cancer was 5.20 (95% CI, 2.38 to 9.88). Particularly high overall SIRs were observed in patients with NF1 age < 15 years: women, 87.6 (95% CI, 58.6 to 125); men, 45.6 (95% CI, 28.4 to 68.5). An estimated lifetime cancer risk for patients with NF1 was 59.6%. The 5-year survival of patients with cancer and NF1, excluding nervous tissue cancers, was worse than that of comparable patients with cancers without NF1 (54.0% v 67.5%; P = .01).

CONCLUSION

Our results emphasize the general cancer proclivity of patients with NF1. These findings should translate to clinical practices to determine clinical interventions and focused follow-up of patients with NF1.

Comparing net survival estimators of cancer patients

The net survival of a patient diagnosed with a given disease is a quantity often interpreted as the hypothetical survival probability in the absence of causes of death other than the disease. In a relative survival framework, net survival summarises the excess mortality that patients experience compared with their relevant reference population. Based on follow-up data from the Finnish Cancer Registry, we derived simulation scenarios that describe survival of patients in eight cancer sites reflecting different excess mortality patterns in order to compare the performance of the classical Ederer II estimator and the new estimator proposed by Pohar Perme et al. At 5 years, the age-standardised Ederer II estimator performed equally well as the Pohar Perme estimator with the exception of melanoma in which the Pohar Perme estimator had a smaller mean squared error (MSE). At 10 and 15 years, the age-standardised Ederer II performed most often better than the Pohar Perme estimator. The unstandardised Ederer II estimator had the largest MSE at 5 years. However, its MSE was often superior to those of the other estimators at 10 and 15 years, especially in sparse data. Both the Pohar Perme and the age-standardised Ederer II estimator are valid for 5-year net survival of cancer patients. For longer-term net survival, our simulation results support the use of the age-standardised Ederer II estimator.

Use of exogenous hormones and the risk of breast cancer: results from self-reported survey data with validity assessment

PURPOSE

Main aim was to estimate the association between use of exogenous hormones and breast cancer (BC) risk in a large population-based survey, and to assess the representativeness and overall validity of the data.

METHODS

The survey 'Women's Health and Use of Hormones' was conducted in Finland in 2009, including 7,000 BC cases and 20,000 matched population controls. Conditional logistic regression was used to estimate odds ratios and their 95 % confidence interval. For validation, exposure prevalences were compared with population data from Statistics Finland and two large population-based surveys.

RESULTS

We found positive associations with BC risk and exclusive use of hormone-releasing intrauterine device (HR IUD) in postmenopausal women (1.48, 95 % CI 1.10-1.99), when compared to never-users of any hormonal contraceptive and considering only prediagnostic use in cases. Regarding use of other hormonal contraceptives (HC), a positive association between long HC use (≥2 years) and BC was observed in both groups, OR being 1.37 (95 % CI 1.12-1.68) for premenopausal and 1.11 (95 % CI 1.03-1.20) for postmenopausal women, when compared to never-users of other HC.

CONCLUSIONS

Observed association between HR IUD use and risk of BC in postmenopausal women is worrying and deserves further attention. Selection bias seemed not to explain this result. Considering the increasing popularity of HR IUD use in, e.g., USA, impact of possible adverse effects in public health could be significant.

Age-related incidence of cervical cancer supports two aetiological components: a population-based register study

OBJECTIVE

To assess whether age-related incidence of cervical cancer supports two aetiological components and to assess trends in these components due to risk factors and to organised screening in Finland.

DESIGN

Population-based register study.

SETTING

Finnish Cancer Registry.

POPULATION

Cervical cancer cases and female population in Finland in 1953-2012.

METHODS

Cervical cancer incidence was estimated using Poisson regression where age-specific incidence consists of two (early-age and late-age) normally distributed components.

MAIN OUTCOME MEASURES

Accumulated net risks (incidences) and numbers of cancer cases attributed to each age-related component by calendar time.

RESULTS

The accumulated cervical cancer incidence in 2008-2012 was only 30% of that in 1953-1962, before the screening started. The fit of the observed age-specific rates and the rates based on the two-component model was good. In 1953-62, the accumulated net risk ratio (RR; early-age versus late-age) was 0.42 (95% CI 0.29-0.61). The early-age component disappeared in 1973-77 (RR 0.00; 95% CI 0.00-0.08). Thereafter, the risk for the early-age component increased, whereas the risk for the late-age component decreased, and in 2008-2012 the RR was 0.55 (95% CI 0.24-0.89).

CONCLUSIONS

In Finland, cervical cancer incidence has two age-related components which are likely to indicate differences in risk factors of each component. The trend in risk of both components followed the effects of organised screening. Furthermore, the risk related to the early-age component followed changes in risk factors, such as oncogenic HPV infections and other sexually transmitted diseases and smoking habits.

TWEETABLE ABSTRACT

Cervical cancer incidence has two age-related components which are likely to have differencies in their aetiology.

Impact of classical risk factors of type 2 diabetes among Asian Indian, Chinese and Japanese populations

AIMS

This review investigated the population impact of major modifiable type 2 diabetes (T2D) risk factors, with special focus on native Asian Indians, to estimate population attributable risks (PARs) and compare them with estimates from Chinese and Japanese populations.

METHODS

Information was obtained on risk factors in 21,041 Asian Indian, 17,774 Chinese and 17,986 Japanese populations from multiple, large, cross-sectional studies (the DECODA project) of T2D. Crude and adjusted PARs were estimated for the major T2D risk factors.

RESULTS

Age had the highest crude and adjusted PARs among Asian Indians and Chinese in contrast to waist-hip ratio among Japanese. After adjusting for age, the PAR for body mass index (BMI) in Asian Indians (41.4% [95% CI: 37.2%; 45.4%]) was second only to triglycerides (46.4% [95% CI: 39.5%; 52.8%]) compared with 35.8% [95% CI: 29.9%; 41.4%] in Japanese and 38.4% [95% CI: 33.5%; 43.2%] in Chinese people. The PAR for BMI adjusted for age, LDL and triglycerides (39.7% [95% CI: 31.6%; 47.2%]) was higher than for any other factor in Asian Indians, and was much higher than in the Chinese (16.8% [95% CI: 3.0%; 30.9%]) and Japanese (30.4% [95% CI: 17.5%; 42.2%]) populations.

CONCLUSION

This review provides estimates of the association between major risk factors and prevalences of T2D among Asian populations by examining their PARs from large population-based samples. From a public-health point of view, the importance of BMI in Asian Indians is especially highlighted in comparison to the other Asian populations. Given these results and other recent findings on the causality link between BMI and T2D, it can be postulated that obesity may be involved in the aetiology of T2D through interaction with ethnic-specific genetic factors, although ethnicity itself is not a direct risk factor for T2D as people of all ethnic backgrounds develop diabetes.

Does Hair Dye Use Increase the Risk of Breast Cancer? A Population-Based Case-Control Study of Finnish Women

INTRODUCTION

Role of hair dyes in the etiology of breast cancer has occasionally raised concern but previous research has concluded with mixed results. Remnants of prohibited aromatic amines have been found in many hair dye products, and elevated levels of DNA-adducts of these amines have been detected from breast epithelial cells of hair dye users. However, the IARC working group has concluded that there is inadequate evidence for carcinogenicity of personal hair dye use and limited evidence in experimental animals for carcinogenicity of hair colorants.

MATERIAL AND METHODS

We investigated whether the use of hair dyes is associated with breast cancer risk in women. The study design was a retrospective population-based case-control study in Finland, with a self-administered questionnaire from 6,567 breast cancer patients, aged 22-60 years and diagnosed in 2000-2007, and their 21,598 matched controls. We report odds ratios (OR) with 95% confidence interval (95% CI) from a conditional logistic regression model applied to the frequency matched sets of cases and controls. Bias-adjusted odds ratios from the sensitivity analysis are also presented.

RESULTS

After adjusting for potential confounders, the odds of breast cancer increased by 23% (OR: 1.23, 95% CI: 1.11-1.36) among women who used hair dyes compared to those who did not. In women born before 1950 an increase of 28% was noted (OR: 1.28, 95% CI: 1.10-1.48). We also observed a significant trend between the OR and cumulative use of hair dyes (P: 0.005). Bias-adjusted odds ratios varied between 1.04 and 2.50.

CONCLUSIONS

Our results suggest that use of hair dyes is associated with breast cancer incidence. The impact on public health may be substantial due to vast popularity of hair coloring in modern societies. It should be noted that regardless of all efforts, a possibility of bias cannot definitively be ruled out and use of a prospective design is warranted. Based on the present results, it may be concluded however that safety of hair dyes in relation to breast cancer cannot yet be fully acknowledged and lack of external safety assessment within the cosmetics industry is of major concern.

Epigenome-wide association of DNA methylation markers in peripheral blood from Indian Asians and Europeans with incident type 2 diabetes: a nested case-control study

BACKGROUND

Indian Asians, who make up a quarter of the world's population, are at high risk of developing type 2 diabetes. We investigated whether DNA methylation is associated with future type 2 diabetes incidence in Indian Asians and whether differences in methylation patterns between Indian Asians and Europeans are associated with, and could be used to predict, differences in the magnitude of risk of developing type 2 diabetes.

METHODS

We did a nested case-control study of DNA methylation in Indian Asians and Europeans with incident type 2 diabetes who were identified from the 8-year follow-up of 25 372 participants in the London Life Sciences Prospective Population (LOLIPOP) study. Patients were recruited between May 1, 2002, and Sept 12, 2008. We did epigenome-wide association analysis using samples from Indian Asians with incident type 2 diabetes and age-matched and sex-matched Indian Asian controls, followed by replication testing of top-ranking signals in Europeans. For both discovery and replication, DNA methylation was measured in the baseline blood sample, which was collected before the onset of type 2 diabetes. Epigenome-wide significance was set at p<1 × 10(-7). We compared methylation levels between Indian Asian and European controls without type 2 diabetes at baseline to estimate the potential contribution of DNA methylation to increased risk of future type 2 diabetes incidence among Indian Asians.

FINDINGS

1608 (11·9%) of 13 535 Indian Asians and 306 (4·3%) of 7066 Europeans developed type 2 diabetes over a mean of 8·5 years (SD 1·8) of follow-up. The age-adjusted and sex-adjusted incidence of type 2 diabetes was 3·1 times (95% CI 2·8-3·6; p<0·0001) higher among Indian Asians than among Europeans, and remained 2·5 times (2·1-2·9; p<0·0001) higher after adjustment for adiposity, physical activity, family history of type 2 diabetes, and baseline glycaemic measures. The mean absolute difference in methylation level between type 2 diabetes cases and controls ranged from 0·5% (SD 0·1) to 1·1% (0·2). Methylation markers at five loci were associated with future type 2 diabetes incidence; the relative risk per 1% increase in methylation was 1·09 (95% CI 1·07-1·11; p=1·3 × 10(-17)) for ABCG1, 0·94 (0·92-0·95; p=4·2 × 10(-11)) for PHOSPHO1, 0·94 (0·92-0·96; p=1·4 × 10(-9)) for SOCS3, 1·07 (1·04-1·09; p=2·1 × 10(-10)) for SREBF1, and 0·92 (0·90-0·94; p=1·2 × 10(-17)) for TXNIP. A methylation score combining results for the five loci was associated with future type 2 diabetes incidence (relative risk quartile 4 vs quartile 1 3·51, 95% CI 2·79-4·42; p=1·3 × 10(-26)), and was independent of established risk factors. Methylation score was higher among Indian Asians than Europeans (p=1 × 10(-34)).

INTERPRETATION

DNA methylation might provide new insights into the pathways underlying type 2 diabetes and offer new opportunities for risk stratification and prevention of type 2 diabetes among Indian Asians.

FUNDING

The European Union, the UK National Institute for Health Research, the Wellcome Trust, the UK Medical Research Council, Action on Hearing Loss, the UK Biotechnology and Biological Sciences Research Council, the Oak Foundation, the Economic and Social Research Council, Helmholtz Zentrum Munchen, the German Research Center for Environmental Health, the German Federal Ministry of Education and Research, the German Center for Diabetes Research, the Munich Center for Health Sciences, the Ministry of Science and Research of the State of North Rhine-Westphalia, and the German Federal Ministry of Health.

Effectiveness of screening for colorectal cancer with a faecal occult-blood test, in Finland

Background

Screening for colorectal cancer (CRC) with guaiac-based faecal occult-blood test (FOBT) has been reported to reduce CRC mortality in randomised trials in the 1990s, but not in routine screening, so far. In Finland, a large randomised study on biennial FOB screening for CRC was gradually nested as part of the routine health services from 2004. We evaluate the effectiveness of screening as a public health policy in the largest population so far reported.

Methods

We randomly allocated (1:1) men and women aged 60–69 years to those invited for screening and those not invited (controls), between 2004 and 2012. This resulted in 180 210 subjects in the screening arm and 180 282 in the control arm. In 2012, the programme covered 43% of the target age population in Finland.

Results

The median follow-up time was 4.5 years (maximum 8.3 years), with a total of 1.6 million person-years. The CRC incidence rate ratio between the screening and control arm was 1.11 (95% CI 1.01 to 1.23). The mortality rate ratio from CRC between the screening and control arm was 1.04 (0.84 to 1.28), respectively. The CRC mortality risk ratio was 0.88 (0.66 to 1.16) and 1.33 (0.94 to 1.87) in males and females, respectively.

Conclusions

We did not find any effect in a randomised health services study of FOBT screening on CRC mortality. The substantial effect difference between males and females is inconsistent with the evidence from randomised clinical trials and with the recommendations of several international organisations. Even if our findings are still inconclusive, they highlight the importance of randomised evaluation when new health policies are implemented.

Trial registration

002_2010_august.

Reference values of spirometry for Finnish adults

BACKGROUND

Diagnostic assessment of lung function necessitates up-to-date reference values. The aim of this study was to estimate reference values for spirometry for the Finnish population between 18 and 80 years and to compare them with the existing Finnish, European and the recently published global GLI2012 reference values.

METHODS

Spirometry was performed for 1380 adults in the population-based FinEsS studies and for 662 healthy non-smoking volunteer adults. Detailed predefined questionnaire screening of diseases and symptoms, and quality control of spirometry yielded a sample of 1000 native Finns (387 men) healthy non-smokers aged 18-83 years. Sex-specific reference values, which are estimated using the GAMLSS method and adjusted for age and height, are provided.

RESULTS

The predicted values for lung volumes are larger than those obtained by GLI2012 prediction for the Caucasian subgroup for forced vital capacity (FVC) by an average 6·2% and 5·1% and forced expiratory volume in 1 s (FEV1) by an average 4·2% and 3·0% in men and women, respectively. GLI2012 slightly overestimated the ratio FEV1/FVC with an age-dependent trend. Most reference equations from other European countries, with the exception of the Swiss SAPALDIA study, showed an underestimation of FVC and FEV1 to varying degrees, and a slight overestimation of FEV1/FVC.

CONCLUSION

This study offers up-to-date reference values of spirometry for native Finns with a wide age range. The GLI2012 predictions seem not to be suitable for clinical use for native Finns due to underestimation of lung volumes.

Hierarchical Bayesian model for rare variant association analysis integrating genotype uncertainty in human sequence data

Next-generation sequencing (NGS) has led to the study of rare genetic variants, which possibly explain the missing heritability for complex diseases. Most existing methods for rare variant (RV) association detection do not account for the common presence of sequencing errors in NGS data. The errors can largely affect the power and perturb the accuracy of association tests due to rare observations of minor alleles. We developed a hierarchical Bayesian approach to estimate the association between RVs and complex diseases. Our integrated framework combines the misclassification probability with shrinkage-based Bayesian variable selection. It allows for flexibility in handling neutral and protective RVs with measurement error, and is robust enough for detecting causal RVs with a wide spectrum of minor allele frequency (MAF). Imputation uncertainty and MAF are incorporated into the integrated framework to achieve the optimal statistical power. We demonstrate that sequencing error does significantly affect the findings, and our proposed model can take advantage of it to improve statistical power in both simulated and real data. We further show that our model outperforms existing methods, such as sequence kernel association test (SKAT). Finally, we illustrate the behavior of the proposed method using a Finnish low-density lipoprotein cholesterol study, and show that it identifies an RV known as FH North Karelia in LDLR gene with three carriers in 1,155 individuals, which is missed by both SKAT and Granvil.

The association of statin use with reduced incidence of venous thromboembolism: a population-based cohort study

OBJECTIVES

Venous thromboembolism (VTE) continues to be a frequent medical emergency requiring rapid recognition so as to reach diagnosis and initiate anticoagulation therapy. The use of statins in addition to reducing the incidence of arterial thrombosis for decreasing the incidence and reoccurrence of VTE is reported. The aim of our study was to explore the association between statin usage and the incidence of new VTE at the population level during a 10-year follow-up.

DESIGN

Population-based historic cohort.

SETTING

The Health 2000 Survey was based on a nationally representative sample.

PARTICIPANTS

8028 individuals aged 30 years or over in Finland.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary end point event was the first ever hospitalisation due to one of the following causes: pulmonary embolism (International Classification of Diseases-10 I26), cerebral venous non-pyogenic thrombosis (I63.6), or venous thrombosis (I80.9-189).

RESULTS

The preselected explanatory variables applied to the Poisson regression model were statin usage (no/yes) during follow-up (2000-2011) and several baseline data (age, sex; usage of blood glucose lowering drugs, vitamin K antagonists and antiplatelet agents). We observed 136 VTE events, the incidence of 1.72 (95% CI 1.44 to 2.04) per 1000 person-years. Current statin usage did not associate with the incidence of VTE according to the univariate model (rate ratio (RR) 0.93, 0.56 to 1.52), but when adjusted with baseline variables (age, sex, medications) the RR declined to 0.60 (0.36 to 1.00, p=0.04).

CONCLUSIONS

Statin use offers protection against first ever VTE events and appears as a primary prevention tool in patients without anticoagulation or antiplatelet medication.

Genome-wide association study on detailed profiles of smoking behavior and nicotine dependence in a twin sample

Smoking is a major risk factor for several somatic diseases and is also emerging as a causal factor for neuropsychiatric disorders. Genome-wide association (GWA) and candidate gene studies for smoking behavior and nicotine dependence (ND) have disclosed too few predisposing variants to account for the high estimated heritability. Previous large-scale GWA studies have had very limited phenotypic definitions of relevance to smoking-related behavior, which has likely impeded the discovery of genetic effects. We performed GWA analyses on 1114 adult twins ascertained for ever smoking from the population-based Finnish Twin Cohort study. The availability of 17 smoking-related phenotypes allowed us to comprehensively portray the dimensions of smoking behavior, clustered into the domains of smoking initiation, amount smoked and ND. Our results highlight a locus on 16p12.3, with several single-nucleotide polymorphisms (SNPs) in the vicinity of CLEC19A showing association (P<1 × 10(-6)) with smoking quantity. Interestingly, CLEC19A is located close to a previously reported attention-deficit hyperactivity disorder (ADHD) linkage locus and an evident link between ADHD and smoking has been established. Intriguing preliminary association (P<1 × 10(-5)) was detected between DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th edition) ND diagnosis and several SNPs in ERBB4, coding for a Neuregulin receptor, on 2q33. The association between ERBB4 and DSM-IV ND diagnosis was replicated in an independent Australian sample. Recently, a significant increase in ErbB4 and Neuregulin 3 (Nrg3) expression was revealed following chronic nicotine exposure and withdrawal in mice and an association between NRG3 SNPs and smoking cessation success was detected in a clinical trial. ERBB4 has previously been associated with schizophrenia; further, it is located within an established schizophrenia linkage locus and within a linkage locus for a smoker phenotype identified in this sample. In conclusion, we disclose novel tentative evidence for the involvement of ERBB4 in ND, suggesting the involvement of the Neuregulin/ErbB signalling pathway in addictions and providing a plausible link between the high co-morbidity of schizophrenia and ND.

Second-generation antihistamines exhibit a protective effect on drivers in traffic-a preliminary population-based case-control study

INTRODUCTION

Although there have been experimental studies concerning driving and drugs, studies on the risk of antihistamines are not numerous. This is the first population-based epidemiological study concerning the association of sedating/nonsedating antihistamines and fatal traffic accidents.

METHODS

Car drivers (n = 428) who died in accidents before reaching the hospital and controls (n = 688) matched for accident area and driving season were studied for antihistamines in blood. At the time of the fatal road traffic accident, 6 drivers had a detectable amount of sedating antihistamines in blood, and the corresponding number for controls was 4; nonsedating antihistamines in blood were detected in 12 accident cases and 28 controls. The fatal accidents occurred between 1998 and 2002 and the information on the controls was collected between 2000 and 2002 in Finland.

RESULTS

Regarding fatal traffic accident causality, the nonsedating antihistamines proved to have a protective effect after adjusting for age and gender (relative risk = 0.40, 95% confidence interval [CI], 0.20 to 0.82; P =.01). The risk of fatal traffic accident of those driving under the influence of sedating antihistamines was 1.61 (0.38 to 6.77, P =.51) times the risk of those without medication.

DISCUSSION

This preliminary study supports the protective effect of second-generation antihistamines with respect to fatal traffic accidents. Due to the small sample size the results are not conclusive.