Order of HPV/Chlamydia infections and cervical high-grade precancer risk: a case-cohort study.

Interactions of carcinogenic human papillomaviruses (most notably HPV types 16/18/31/33/45), and HPV6 or Chlamydia trachomatis are not well understood. We have used seroconversions to study effects the order of these infections has on the risk of high-grade cervical precancer. In a cohort of 94,349 Finnish women with paired sera from consecutive pregnancies within an average of 2.

Prospective seroepidemiologic study of human papillomavirus and other risk factors in cervical cancer.

Background: Several sexually transmitted infections (STI) have been reported to interact with human papillomavirus (HPV) in the etiology of cervical cancer. A large cohort study is required to obtain a both unbiased and stable estimate of their effects.

Methods: Four major biobanks in the Nordic Countries containing samples from about 1,000,000 subjects were linked with nation-wide cancer registries.

Circulating estrogens and progesterone during primiparous pregnancies and risk of maternal breast cancer.

Pregnancy reduces maternal risk of breast cancer in the long term, but the biological determinants of the protection are unknown. Animal experiments suggest that estrogens and progesterone could be involved, but direct human evidence is scant. A case-control study (536 cases and 1,049 controls) was nested within the Finnish Maternity Cohort.

Circulating sex steroids during pregnancy and maternal risk of non-epithelial ovarian cancer.

Background: Sex steroid hormones have been proposed to play a role in the development of non-epithelial ovarian cancers (NEOC) but so far no direct epidemiologic data are available.

Methods: A case-control study was nested within the Finnish Maternity Cohort, the world's largest biorepository of serum specimens from pregnant women. Study subjects were selected among women who donated a blood sample during a singleton pregnancy that led to the birth of their last child preceding diagnosis of NEOC.

Lack of association between human papillomavirus type 16 and 18 infections and female lung cancer.

Background: A carcinogenic role of human papillomavirus (HPV) in lung cancer development has been suggested through both clinical and laboratory research during the last two decades.

Methods: We did a population-based case-control study nested within the Finnish Maternity Cohort to assess the role of HPV16/18 infections in female lung carcinogenesis. The Finnish Maternity Cohort containing samples from more than 600,000 subjects were linked with nationwide cancer registries (1973-2006).

Population fraction of cervical neoplasia attributable to high-risk human papillomaviruses.

Aims: The efficacy of human papillomavirus (HPV) type 16 and 18 vaccines against cervical intraepithelial neoplasia grade II (CIN2+) has been verified, but the active follow-up of studies with invasive cervical cancer or cervical intraepithelial neoplasia grade III (CIN3) as primary end points are ethically not possible. Furthermore, ongoing registry-based passive follow-up studies with invasive cervical cancer as the end point will take time.

Materials & Methods: To evaluate the feasibility of CIN3 as a surrogate end point, we compared high-risk (hr) HPV-associated relative risk and population attributable fraction (PAF) of CIN3 and/or squamous cell carcinoma (SCC) estimated in a large serological case-cohort HPV study.

Risk of being seropositive for multiple human papillomavirus types among Finnish and Ugandan women.

Although infections with multiple human papillomavirus (HPV) types have been reported widely, more information is needed on the occurrence of the different types. We determined the distribution of seroprevalences to multiple HPV types in Finland and Uganda to compare the epidemiology of the different HPV types in the 2 populations. Serum samples were obtained from 2784 Finnish and 1964 Ugandan women (mean ages 22 y and 25 y, respectively) of whom 44% and 57%, respectively, had antibodies to at least 1 of the 7 HPV types (6, 11, 16, 18, 31, 33, 45) tested (p < 0.

Population dynamics of serologically identified coinfections with human papillomavirus types 11, 16, 18 and 31 in fertile-aged Finnish women.

Licensed human papillomavirus (HPV) vaccines are expected to prevent high-risk (hr) HPV-infections (most notably types 16 and 18). Whether HPV vaccination will change the distribution of hrHPVs at the population level is open, since competition between HPV types is not well understood. Two stratified random subcohorts (1983-1997 and 1995-2003) of 7,815 and 3,252 women with a minimum of 2 pregnancies (<32 years) were selected from the Finnish Maternity Cohort.

Time trends in allergic sensitisation and Helicobacter pylori prevalence in Finnish pregnant women.

Background: An increase in the prevalence of allergic conditions has been documented in Finland, correlating with the diminishing prevalence of Helicobacter pylori infections. We investigated whether the increase of allergic sensitisation still continues and correlates with the prevalence of H. pylori infections.

Endogenous steroid hormone levels in early pregnancy and risk of testicular cancer in the offspring: a nested case-referent study.

According to the leading hypothesis on testicular cancer (TC) etiology exposure to a specific pattern of steroid hormones in utero, in particular, to high levels of estrogens and low levels of androgens is the major determinant of TC risk in the offspring. We performed a case-referent study nested within Finnish, Swedish and Icelandic maternity cohorts exploiting early pregnancy serum samples to evaluate the role of maternal endogenous steroid hormones with regard to the risk of TC. TC cases and referents were aged between 0 and 25 years.

Maternal smoking during pregnancy and testicular cancer in the sons: a nested case-control study and a meta-analysis.

Some large ecological studies have noted a significant association of testicular cancer (TC) with maternal smoking during pregnancy, while several more controlled studies have been negative. It has been difficult to obtain reliable data on exposure because of the long lag time to cancer diagnosis. We performed a case-control study nested within Finnish, Swedish and Icelandic maternity cohorts exploiting early pregnancy serum samples to evaluate the role of maternal smoking in the risk of TC in the offspring.

A discrepancy of Chlamydia trachomatis incidence and prevalence trends in Finland 1983-2003.

Background: Reported rates of Chlamydia trachomatis are on the rise contradicting the declining rates of C. trachomatis associated reproductive sequelae in Western countries. Population based evaluation of the real trend of C.

Smoking impairs human papillomavirus (HPV) type 16 and 18 capsids antibody response following natural HPV infection.

The natural history of oncogenic human papillomavirus (HPV) infections results from interactions of the virus, the host, and multiple cofactors. We studied the association between humoral immune response to HPV and smoking in 191 HPV infected women prospectively. Two follow-up samples (first and last) were analysed for serum cotinine levels, IgA and IgG antibodies to HPV16 and 18, and Chlamydia trachomatis using ELISA methods.

Is smoking an independent risk factor for invasive cervical cancer? A nested case-control study within Nordic biobanks.

The strong correlation between smoking and exposure to oncogenic human papillomaviruses (HPVs) has made it difficult to verify the independent role of smoking in cervical carcinogenesis. Thus, the authors evaluated this role. Five large Nordic serum banks containing samples from more than 1,000,000 subjects were linked with nationwide cancer registries (1973-2003).

Maternal Epstein-Barr virus and cytomegalovirus infections and risk of testicular cancer in the offspring: a nested case-control study.

During recent decades the incidence of testicular cancer (TC) has increased rapidly around the world. Associated exogenous etiological factors might therefore be identifiable. We performed a case-control study nested within Finnish, Swedish and Icelandic maternity cohorts exploiting early pregnancy serum samples to evaluate the role of congenital or neonatal infections with Epstein-Barr virus (EBV) and cytomegalovirus (CMV) as risk factors of TC in the offspring.

Maternal serum Chlamydia pneumoniae antibodies and CRP levels in women with preeclampsia and gestational hypertension.

Objective: To determine whether Chlamydia pneumoniae antibodies and highly sensitive C-reactive protein (hsCRP) levels in maternal sera are associated with preeclampsia or gestational hypertension.

Methods: C. pneumoniae antibodies and hsCRP levels were measured in maternal serum during first trimester (mean, 10.

Insulin resistance and depressive symptoms in young adult males: findings from Finnish military conscripts.

Objective: To investigate whether the association between insulin resistance (IR) and depressive symptoms is present already in young adult males. The association between IR and depression has been poorly studied, although the existence of a connection of Type II diabetes with depression is well established. We previously demonstrated at epidemiological level in two groups of men aged 31 years and 61 to 63 years that IR is linked with depressive symptoms.

Effect of long-term storage on hormone measurements in samples from pregnant women: the experience of the Finnish Maternity Cohort.

Validity of biobank studies on hormone associated cancers depend on the extent the sample preservation is affecting the hormone measurements. We investigated the effect of long-term storage (up to 22 years) on immunoassay measurements of three groups of hormones and associated proteins: sex-steroids [estradiol, progesterone, testosterone, dihydroepiandrosterone sulphate (DHEAS), sex hormone-binding globulin (SHBG)], pregnancy-specific hormones [human chorionic gonadotropin (hCG), placental growth hormone (pGH), alpha-fetoprotein (AFP)], and insulin-like growth factor (IGF) family hormones exploiting the world largest serum bank, the Finnish Maternity Cohort (FMC). Hormones of interest were analyzed in a random sample of 154 Finnish women in the median age (29.

Maternal antibodies in breast milk protect the child from enterovirus infections.

Objective: Enterovirus infections are frequent in infants and may cause severe complications. We set out to assess whether breastfeeding can protect against these infections and whether such an effect is related to maternal antibodies in breast milk or in the peripheral circulation of the infant.

Methods: One hundred fifty infants who were prospectively followed up from birth were monitored for enterovirus infections.

Nordic biological specimen banks as basis for studies of cancer causes and control--more than 2 million sample donors, 25 million person years and 100,000 prospective cancers.

The Nordic countries have a long tradition of large-scale biobanking and comprehensive, population-based health data registries linkable on unique personal identifiers, enabling follow-up studies spanning many decades. Joint Nordic biobank-based studies provide unique opportunities for longitudinal molecular epidemiological research. The purpose of the present paper is to describe the possibilities for such joint studies, by describing some of the major Nordic biobank cohorts with a standardised calculation of the cancer incidence in these cohorts.

The Pro12Ala polymorphism of the PPAR gamma 2 gene influences sex hormone-binding globulin level and its relationship to the development of the metabolic syndrome in young Finnish men.

Association of low sex hormone-binding globulin (SHBG) level with the risk of the metabolic syndrome (MetS) in men has previously been reported. A proline to alanine substitution in codon 12 of the peroxisome proliferator activated receptor gamma 2 (PPARgamma2) gene has been shown to be related to high insulin sensitivity. The relationship of SHBG levels with the Pro12Ala polymorphism of PPARgamma2 in men has not been previously studied.

Atopy and risk of non-Hodgkin lymphoma.

Background: A possible connection between allergy and cancer has been suspected, but allergy-related conditions or atopy have been inconsistently associated with reduced risks of non-Hodgkin lymphoma. We investigated this association in a population-based case-control study and in a prospective study with prediagnostic blood specimens.

Methods: We carried out a population-based study of 3055 case patients with non-Hodgkin lymphoma and 3187 control subjects in Denmark and Sweden, including questionnaire information on allergy and blood specimens, and a nested case-control study within a prospective cohort of more than 400,000 Finnish women.

Activation of maternal Epstein-Barr virus infection and risk of acute leukemia in the offspring.

After identifying an association between maternal Epstein-Barr virus (EBV) reactivation and acute lymphoblastic leukemia (ALL), the authors analyzed a nested case-control study within Finnish and Icelandic maternity cohorts with 7 million years of follow-up to confirm EBV's role in ALL. Offspring of 550,000 mothers were followed up to age 15 years during 1975-1997 by national cancer registries to identify leukemia cases. Mothers of cases and three quarters of matched mothers of controls were identified by national population registers.

Seroprevalence atlas of infections with oncogenic and non-oncogenic human papillomaviruses in Finland in the 1980s and 1990s.

Vaccines against high-risk (hr) human papillomaviruses (HPVs) causing cervical cancer may soon be licensed. Thus, nature of HPV epidemics needs to be studied now. Random sampling for studies on HPV epidemiology was done from all 230,998 women belonging to the population-based Finnish Maternity Cohort and having a minimum of 2 pregnancies between 1983 and 1994.