Inverse probability weighting for self-selection bias correction in the investigation of social inequality in mortality.

Background: Empirical evaluation of inverse probability weighting (IPW) for self-selection bias correction is inaccessible without the full source population. We aimed to: (i) investigate how self-selection biases frequency and association measures and (ii) assess self-selection bias correction using IPW in a cohort with register linkage.

Methods: The source population included 17 936 individuals invited to the Copenhagen Aging and Midlife Biobank during 2009-11 (ages 49-63 years).

The relationship between self-perceived fatigue, muscle endurance, and circulating markers of inflammation in participants of the Copenhagen aging and Midlife Biobank (CAMB).

Background: Fatigue, low muscle endurance, muscle weakness and low-grade inflammation are strongly related to frailty at higher age. When signs of self-perceived fatigue and low muscle endurance are interrelated with low-grade inflammation at midlife, they might be used as early markers for frailty. This study investigated whether the interrelationships among self-perceived fatigue, muscle endurance and inflammation can be observed at midlife.

Educational attainment in young adulthood and self-rated health in midlife - Does allostatic load mediate the association?

This study aimed to examine the extent to which allostatic load (AL), measured in midlife, mediates the association between educational attainment in young adulthood and self-rated health (SRH) in midlife among women and men. The study used data from the Copenhagen Aging and Midlife Biobank (CAMB; n = 5467 participants, aged 48-62 years, 31.5% women).

Health, well-being and social relations in a changing neighbourhood: protocol for a prospective, multimethods study of the consequences of large structural changes in an ethnic diverse social housing area in Denmark.

Introduction: Residential areas constitute an important arena for health, well-being and social relations. Structural interventions such as demolition and area renewal have been used to reduce inequality in health and well-being in disadvantaged areas. However, the effects of larger structural interventions are inconclusive.

Lewis and AB0 blood group-phenotypes in periodontitis, cardiovascular disease, obesity and stroke.

The AB0 blood group has been linked to ischaemic heart disease, stroke, and periodontal disease, while the Lewis blood group has been linked to ischaemic heart disease and obesity, all of which have been associated with periodontitis. AB0 or Lewis blood group phenotype may therefore constitute common hereditary components predisposing to these disorders. In this study, we investigated if blood group phenotype associated with periodontitis in a subpopulation consisting of 702 participants from a Danish cross-sectional cohort and, secondarily, attempted to confirm their association with hypertension, ischaemic heart disease, stroke, and obesity.

Grip Work Measurement with the Jamar Dynamometer: Validation of a Simple Equation for Clinical Use.

Objectives: Previously, we developed and validated an easy test to measure muscle fatigability during sustained maximal handgrip contraction in older persons using a Martin Vigorimeter device. This study aimed at validating the equation to estimate grip work (GW) during sustained maximal handgrip contraction, by monitoring continuously the grip strength (GS) decay using a Jamar Dynamometer-like (JD) device.

Design: Cross sectional, explorative study.

Single nucleotide polymorphisms in genes encoding toll-like receptors 7, 8 and 9 in Danish patients with systemic lupus erythematosus.

Several studies indicate a role for toll-like receptors (TLRs) in the pathogenesis of systemic lupus erythematosus (SLE). We aimed to investigate the risk of SLE and typical clinical and serological manifestations of SLE potentially conferred by selected single nucleotide polymorphisms (SNPs) of genes encoding TLR7, TLR8, and TLR9. Using a multiplexed bead-based assay, we analyzed eight SNPs in a cohort of 142 Danish SLE patients and a gender-matched control cohort comprising 443 individuals.

Cohort Profile: The Danish Conscription Database(DCD): A cohort of 728,160 men born from 1939 through 1959.

The Danish Conscription Database (DCD) was established to enable studies of the influence of early physical and mental exposures on adverse health and social outcomes from a life-course perspective. In Denmark, all young men are requested to appear before the conscription board when they turn 18 years, to be assessed for military service. The DCD was established by digitizing information from conscription board register cards on the height, weight, educational level, intelligence test score and examination details of Danish conscripts.

Associations of subjective vitality with DNA damage, cardiovascular risk factors and physical performance.

Aim: To examine associations of DNA damage, cardiovascular risk factors and physical performance with vitality, in middle-aged men. We also sought to elucidate underlying factors of physical performance by comparing physical performance parameters to DNA damage parameters and cardiovascular risk factors.

Methods: We studied 2487 participants from the Metropolit cohort of 11 532 men born in 1953 in the Copenhagen Metropolitan area.

Social class differences in physical functions in middle-aged men and women.

Objective: The objective of the present study is to analyze gender differences and social class gradients in physical functions; and to study whether the social class gradients in physical functions in midlife differed between men and women.

Method: This study used traditionally used physical performance tests and we added several tests of vigorous physical functioning (trunk muscle strength and power and sagittal flexibility). We measured reaction time, one-legged balance, sagittal flexibility, jump height, chair rise ability, trunk muscle- and handgrip strength in 5,412 participants aged 50 to 60 years (68.

Social gradient in allostatic load among Danish men and women in late midlife.

Objective: The objective of the present study is to describe the prevalence of allostatic load (AL) among Danish men and women in late midlife, and if there is a social gradient in AL.

Method: A total of 5,420 participants from the Copenhagen Aging and Midlife Biobank (CAMB) aged 48 to 63 years (68.5% men, 31.

Smoking and drinking as risk indicators for tooth loss in middle-aged Danes.

Objectives: To investigate tobacco and alcohol consumption as risk indicators for missing teeth in late middle-aged Danes.

Method: In all, 1,517 Copenhagen Aging and Midlife Biobank (CAMB) participants received a clinical oral examination that included number of teeth. Information on smoking, drinking, and various covariates was obtained using self-administered, structured questionnaires.

The relationship between cognitive ability and demographic factors in late midlife.

Objective: The aim of the article is to analyze associations between sex, age, education, and social class and cognitive ability in late midlife and to evaluate differences in cognitive ability among the three Copenhagen Aging and Midlife Biobank (CAMB) cohorts.

Method: The sample comprised 5,417 CAMB participants from three cohorts with scores on the Intelligenz-Struktur-Test 2000 R (I-S-T 2000 R).

Results: Independent associations of cognitive ability with age, sex, education, and occupational social class were observed.

Personality in late midlife: associations with demographic factors and cognitive ability.

Objectives: To analyze associations in late midlife between sex, age, education and social class, and the Big Five personality traits; to analyze associations between personality traits and cognitive ability in late midlife; and to evaluate how these associations are influenced by demographic factors.

Methods: The study sample comprised 5,397 late midlife participants from three cohorts who had completed the NEO Five-Factor Inventory (NEO-FFI) and a measure of cognitive ability.

Results: Associations were demonstrated between the five NEO-FFI personality traits, and all included demographic factors.

Disclosure patterns of mode of conception among mothers and fathers-5-year follow-up of the Copenhagen Multi-centre Psychosocial Infertility (COMPI) cohort.

Background: Most studies on disclosure of mode of conception after fertility treatment have focused on donor insemination. We present a large, longitudinal cohort study of fertility patients who conceived through a variety of fertility treatments, including both non-donor and donor techniques.

Methods: A cohort of 2812 women and men (n = 1406 couples) received questionnaires when initiating fertility treatment and at 1-year and 5-year follow-ups.

Prospective longitudinal cohort study on cumulative 5-year delivery and adoption rates among 1338 couples initiating infertility treatment.

Background: The objective was to assess crude 5-year delivery rates after assisted reproductive technology (ART) treatment, intrauterine inseminations (IUI), spontaneous conceptions (SC) and adoptions in a large infertile cohort.

Methods: A prospective longitudinal survey comprised 1338 infertile couples starting public infertility programmes offering IUIs and three free ART cycles during 2000-2001. The cohort was cross-linked with the National Medical Birth Register to obtain delivery rates for all 1338 couples.

Exposure to bullying at school and depression in adulthood: a study of Danish men born in 1953.

Background: Bullying among children is associated with high symptom load and depression. There is little knowledge about long-term consequences of bullying. The aim of the present study is to examine the association between recall of bullying at school and depression in midlife controlling for adult social class and parents' mental health.

Inbreeding and population structure in two pairs of cryptic fig wasp species.

We used recently developed microsatellites to directly estimate inbreeding levels in two pairs of coexisting cryptic fig wasp species ('Pegoscapus hoffmeyeri sp. A and sp. B', 'P.

Cryptic species of fig-pollinating wasps: implications for the evolution of the fig-wasp mutualism, sex allocation, and precision of adaptation.

Fig-pollinating wasps have provided model systems for developing and testing theories of the evolution of mutualism, sex allocation, and precision of adaptation. With few exceptions, previous studies have assumed one species of pollinator wasp per host fig species. Here we report genetic data demonstrating the coexistence of previously undetected cryptic fig wasp species in at least half of the host fig species surveyed.

The distribution of Wolbachia in fig wasps: correlations with host phylogeny, ecology and population structure.

We surveyed for the presence and identity of Wolbachia in 44 species of chalcid wasps associated with 18 species of Panamanian figs. We used existing detailed knowledge of the population structures of the host wasps, as well as the ecological and evolutionary relationships among them, to explore the relevance of each of these factors to Wolbachia prevalence and mode of transmission. Fifty-nine per cent of these wasp species have Wolbachia infections, the highest proportion reported for any group of insects.