Search PubMed⌕ Search

Biomedical subjects

B Jeune

Publications and source records attributed to B Jeune.

At least 19 recordsLinked to original sources
PubMed2006

Short time-frame from first to second hip fracture in the Funen County Hip Fracture Study.

INTRODUCTION: Hip fracture patients represent a frail group of elderly with increased morbidity and mortality. The aim of this study was to evaluate the occurrence and distribution of a second hip fracture in the time interval between the first and the second hip fracture. METHODS: All incident hip fractures in residents of Funen County, Denmark, from 1994 through 2004 were recorded. Verified fractures were sequenced within each patient using the unique Danish identification numbers. RESULTS: In total, 9990 incident hip fractures occurred: 9122 first hip fractures and 868 (8.7%) second fractures. Within the first year after the first hip fracture, the incidence rate of the second fracture in men decreased from 73 per 1000 person-years (py) during the first 3 months to 8 per 1000 py at 12 months; in women, it decreased from 116 per 1000 py during the first 3 months to 15 per 1000 py at 12 months. Of all the second fractures, 50% occurred within 12 months in men and within 19 months in women. CONCLUSIONS: Few hip fracture patients experience a second hip fracture and when they do, it is within a short time-frame from the first. The risk of sustaining a second hip fracture is high during the first 12 months following the first hip fracture, decreasing to a level equal to or below the incidence of the first hip fracture after this 12-month period. Preventive strategies at the time of the first hip fracture should therefore aim at immediate effects, as interventions with effects after 12 months (men) and 19 months (women) bypass at least 50% of the fractures.

Age Distribution↗
PubMed2004

Modest implication of interleukin-6 promoter polymorphisms in longevity.

The multifunctional interleukin-6 has been suggested to contribute to a chronic low-grade inflammatory status, thereby conferring susceptibility to age-related pathological conditions as well as functional decline and increased mortality. Several polymorphisms have been identified in the interleukin-6 promoter, but investigation of the effect of these on interleukin-6 levels and disease susceptibility have led to contradictory results. This study investigates the significance of the three single-point polymorphisms (-597G/A, -572G/C and -174G/C) and the AT-stretch polymorphism (-373(A)n(T)m) in ageing, by comparison of the frequency of each single polymorphism separately as well as the entire promoter haplotype in a total of 1710 Danish subjects ranging in age from 47 to 100 years. We found a modest, but significant, increase in the frequency of interleukin-6 -174GG homozygotes with age suggesting that this genotype is advantageous for longevity.

Adolescent↗
PubMed2004

High prevalence of autoantibodies among Danish centenarians.

The aim of this study was to investigate the prevalence of organ and nonorgan specific autoantibodies in relation to disability and comorbidity in an unselected population of centenarians. A population-based survey of all persons living in Denmark who celebrated their 100th birthday during the period 1 April 1995 to 31 May 1996, a total of 276 persons, was undertaken. Participants underwent an interview, a physical examination and blood sampling. Organ specific autoantibodies (Tg-ab, TPO-ab, PCA-ab) and nonorgan specific autoantibodies (ANA, IgM RF, IgA RF, MPO-ab, c-ANCA, p-ANCA, oxLDL-ab, IgM ACA, IgG ACA, PR3-ANCA, histone-ab, SSA-ab, SSB-ab, Mit-ab) were measured, and comorbidity and disability (Katz Index of ADL) were registered. In all, 207 (75.0%) of 276 eligible subjects participated, and 148 agreed to blood tests. A large majority (79.3%) had at least one autoantibody detected. Organ specific autoantibodies were present in 32.1% of the centenarians. The high level of autoantibodies did not reflect an equally high level of overt autoimmune disease. While nonorgan specific autoantibodies were equally represented in less-disabled/disabled subjects as well as in subjects with low/high comorbidity, significantly fewer subjects with organ specific autoantibodies were found among less-disabled subjects or subjects with low comorbidity. Autoantibodies (both nonorgan and organ specific) are common in an unselected population of centenarians of today, but do not reflect an equally high level of overt autoimmune disease. Non-organ specific autoantibodies are evenly distributed irrespective of the level of disability or comorbidity, suggesting underlying, undiagnosed pathological processes which may be part of the processes involved in frailty.

Aged↗
PubMed2001

Association of mutations in the hemochromatosis gene with shorter life expectancy.

BACKGROUND: To investigate whether the frequency of carriers of mutations in the HFE gene associated with hereditary hemochromatosis diminishes with age as an indication that HFE mutations are associated with increased mortality. It is of value in the debate concerning screening for hereditary hemochromatosis to determine the significance of heterozygosity. METHODS: Genotyping for mutations in exons 2 and 4 of the HFE gene using denaturing gradient gel electrophoresis in 1784 participants aged 45 to 100 years from 4 population-based studies: all 183 centenarians from the Danish Centenarian Study, 601 people aged 92 to 93 years from the Danish 1905 Cohort, 400 aged 70 to 94 years from the Longitudinal Study of Aging Danish Twins, and 600 aged 45 to 67 years from a study of middle-aged Danish twins. RESULTS: All participants (N=1784) were screened for mutations in exon 4, and a trend toward fewer heterozygotes for the C282Y mutation-the mutation most often associated with hereditary hemochromatosis-was found. This was significant for the whole population (P=.005) and for women (P=.004) but not for men (P=.26). A group of 599 participants was screened for mutations in exon 2, and there was no variation in the distribution of mutations in exon 2 in the different age groups. CONCLUSIONS: In a high-carrier frequency population like Denmark, mutations in HFE show an age-related reduction in the frequency of heterozygotes for C282Y, which suggests that carrier status is associated with shorter life expectancy.

Age Distribution↗
PubMed2001

[Continuously diminishing menarcheal age in Denmark].

INTRODUCTION: The aim was to follow the development of the parameters of the distribution of age at menarche in Danish women in recent decades. MATERIAL AND METHODS: The study is based on retrospective data from six different samples with a total of 42,784 women, born in the period 1923-1973. RESULTS: We report a renewed decline in the mean menarcheal age in a large Danish sample after a period with a halt in the trend towards an earlier age at menarche in many North European countries. We find a continuously declining mean menarcheal age in Denmark in women born in the years 1964-1973. In a sample of textile workers born in the years 1939-1968 (n = 12,605) we find a higher mean menarcheal age of one year. DISCUSSION: The results indicate that menarcheal age is still delayed in certain groups in Denmark. It can therefore be expected that the menarcheal age will fall even more in the future.

Adolescent↗
PubMed2001

Recent advances in human gene-longevity association studies.

This paper reviews the recent literature on genes and longevity. The influence of genes on human life span has been confirmed in studies of life span correlation between related individuals based on family and twin data. Results from major twin studies indicate that approximately 25% of the variation in life span is genetically determined. Taking advantage of recent developments in molecular biology, researchers are now searching for candidate genes that might have an influence on life span. The data on unrelated individuals emerging from an ever-increasing number of centenarian studies makes this possible. This paper summarizes the rich literature dealing with the various aspects of the influence of genes on individual survival. Common phenomena affecting the development of disease and longevity are discussed. The major methodological difficulty one is confronted with when studying the epidemiology of longevity involves the complexity of the phenomenon, which arises from the polygenic nature of life span and historical mortality change. We discuss this issue and suggest new methodological approaches.

Humans↗
PubMed2001

Variations of cardiovascular disease associated genes exhibit sex-dependent influence on human longevity.

This article investigates the relationship between the polymorphic variations in genes associated with cardiovascular disease and longevity in the Danish population. A new procedure that combines both demographic and the individual genetic information in determining the relative risks of the observed genetic variations is applied. The sex-dependent influences can be found by introducing sex-specific population survival and incorporating the risk of gene-sex interaction. Three genetic polymorphisms, angiotensinogen M/T235, blood coagulation factor VII (FVII) R/Q353 and FVII-323ins10, manifest significant influences on survival in males, with reduced hazards of death for carriers of the angiotensinogen M235 allele, the F VII Q353 allele, and the FVII-323P10 allele. The results show that some of these genotypes associated with lower risk of CVD could also reduce the carrier's death rate and contribute to longevity. However, the presence of sex-dependent effects and the fact that major CVD-associated genes failed to impose detrimental influence on longevity lead us to concur that the aging process is highly complicated.

Alleles↗
PubMed2001

Non-independence of individuals in a population of Drosophila melanogaster: effects on spatial distribution and dispersal.

We used a simple quadrat analysis to globally categorise the spatial distribution of Drosophila melanogaster individuals. Individuals were spatially aggregated and this was not only due to sexual attraction. This aggregation seemed to be maintained during dispersal, hence explaining the great variability of this behaviour observed in our work and by other authors. Thus, individuals are expected to arrive as small groups into a new patch. This may induce costs through competition and benefits by ensuring the presence of reproductive mates and/or if there is a phenomenon of local resource enhancement by the presence of conspecifics, hence influencing the evolution of dispersal.

Animals↗
PubMed2001

Outbreak of Hepatitis B among injecting drug users in Denmark.

BACKGROUND: The incidence of hepatitis B is low in Denmark, but injecting drug users (IDUs) remains a high-risk group for this infection. OBJECTIVES: The aim of the study was to describe a hepatitis B outbreak among IDUs by comparing existing registers. Additionally, we wanted to analyze the genetic variation of the hepatitis B virus involved in the outbreak. STUDY DESIGN: In the County of Funen, registers of laboratory diagnosis, hospital records and reports from clinicians to the Medical Officer of Health (MOH) were compared between 1992 and 1998. HBsAg positive sera recovered from the epidemic were sequenced and compared to known HBV strains. RESULTS: We identified 648 cases of hepatitis B of which 51% (332) were acute infections. The laboratory database identified 96% (319/332) of these, 45% (150/332) were admitted to hospital and 38% (127/332) were reported to public health. By capture-recapture analysis based on MOH reports and hospital records the estimated total number of acute cases were 334 (95% C.I. 283-385). We sequenced 75 HBsAg positive samples and identified two very similar strains of genotype D (serotype ayw3) among IDUs involved in the outbreak. CONCLUSIONS: The current surveillance system did not detect the majority of acute hepatitis B cases in County of Funen. We suggest laboratory-based surveillance of hepatitis B to be implemented at a national level as this may identify new outbreaks faster and more complete than the current surveillance system.

Denmark↗
PubMed2001

Replication studies in longevity: puzzling findings in Danish centenarians at the 3'APOB-VNTR locus.

In Danes we replicated the 3'APOB-VNTR gene/longevity association study previously carried out in Italians, by which the Small alleles (less than 35 repeats) had been identified as frailty alleles for longevity. In Danes, neither genotype nor allele frequencies differed between centenarians and 20-64-year-old subjects. However, when Danish and Italian data were compared, a significant difference (p = 0.0004) was found between the frequencies of Small alleles in youths, which disappeared in centenarians (p = 0.290). Furthermore, the demographic-genetic approach revealed in Danes a significant gene-sex interaction relevant to Long alleles (more than 37 repeats). The different findings in Denmark and Italy suggest that gene/longevity associations are population-specific, and heavily affected by the population-specific genetic and environmental history.

Adult↗
PubMed2001

Functional status and self-rated health in 2,262 nonagenarians: the Danish 1905 Cohort Survey.

OBJECTIVES: To describe the functional capacity and self-rated health of a large cohort of nonagenarians. DESIGN: A cross-sectional survey of all Danes born in 1905 (92-93 years of age), carried out August to October 1998. SETTING: Participants' homes. PARTICIPANTS: Two thousand two hundred and sixty-two nonagenarians, corresponding to a participation rate of 63% (of these, 20% participated by proxy). MEASUREMENTS: Activities of daily living (ADLs) and self-rated health were assessed by interview. Five items from Katz's ADLs (bathing, dressing, transfer, toileting, and eating) were used to construct a three-level five-item ADL scale (not disabled (no disabilities), moderately disabled (1-2 disabilities), severely disabled (3-5 disabilities)). From responses to a more extensive list of questions on ADLs (26 items), we identified scales of strength and agility by means of factor analysis. Furthermore, a 26-item ADL scale was made. Physical performance tests (chair stand, timed walk, lifting a 2.7 kg box, maximum grip-strength, and flexibility tests) were performed among nonproxy responders. RESULTS: According to the five-item ADL scale, 50% of the men and 41% of the women were categorized as not disabled, while 19% and 22%, respectively, were categorized as severely disabled. The five-item ADL scale correlated highly with the 26-item ADL scale (r = 0.83). The ADL scales showed moderate-to-good correlation with each other (r = 0.74-0.83), and with the physical performance tests (r = 0.31-0.58). Only 3.7% of the women and 6.3% of the men walked (normal pace) with a speed of at least 1 meter per second, which is the minimum walking speed required to cross signaled intersections in Denmark. A total of 56% considered their health to be excellent or good. Of the participants, 74% were always or almost always satisfied with their lives, even though only 45% reported that they "felt well enough to do what they wanted." The analyses showed that no single ADL item seemed to be of particular importance for how the participants rated their health. CONCLUSION: The Danish 1905 cohort survey is the largest and the only nationwide survey of a whole birth-cohort of nonagenarians. A total of 2,262 fairly nonselected nonagenarians participated. The level of both self-reported disability and functional limitations measured by physical performance tests among nonagenarians was high. Despite their lower mortality, women were more disabled than men and did not perform as well as men in the physical performance tests. Nevertheless, the majority of the participants considered their health to be good and were satisfied with their lives.

Activities of Daily Living↗
PubMed2001

Healthy centenarians do not exist, but autonomous centenarians do: a population-based study of morbidity among Danish centenarians.

OBJECTIVE: To assess the prevalence of common illnesses in an unselected population of centenarians. DESIGN: A population-based survey. SETTING: Denmark. PARTICIPANTS: All Danes who celebrated their 100th anniversary between April 1, 1995 and May 31, 1996: 276 persons. MEASUREMENTS: All participants (including proxies) were visited at their domicile for an interview (sociodemographic characteristics, activities of daily living, living conditions, need of assistance from other people, former health and current diseases, current medication) and a clinical examination (dementia screening test, heart and lung auscultation, neurological assessment, height and weight, electrocardiogram, arm and ankle blood pressure, assessment of hearing and vision capacity, a short physical performance test, bio-impedance, lung function test, blood test). Further health information was retrieved from medical files and national health registers. RESULTS: Seventy-five percent (207) of eligible subjects participated in the study. Cardiovascular disease was present in 149 (72%) subjects. Osteoarthritis (major joints) was present in 54%, hypertension (> or =140/ > or =90) in 52%, dementia in 51%, and ischemic heart disease in 28%. The mean number of illness was 4.3 (standard deviation (SD) 1.86). Only one subject was identified as being free from any chronic condition or illness. Sixty percent had been treated for illness with high mortality. In 25 autonomous (nondemented, functioning well physically, living at home) and 182 nonautonomous centenarians, comorbidities were equivalent. CONCLUSION: Because they have a high prevalence of several common diseases and chronic conditions, Danish centenarians are not healthy. However, a minor proportion was identified as being cognitively intact and functioning well.

Activities of Daily Living↗
PubMed2001

Dementia is not inevitable: a population-based study of Danish centenarians.

The authors evaluated the prevalence of dementia in centenarians. In this population-based survey, persons living in Denmark who turned 100 during the period April 1, 1995--May 31, 1996 (N = 276) were interviewed and examined at their residences. Additional health information was retrieved from medical files, including the National Discharge Registry. A participation rate was 75%, and no differences were found between participants and nonparticipants regarding sex and type of housing. The prevalence of mild to severe dementia in centenarians was 51%; 37% had no signs of dementia. Among the 105 demented centenarians, 13 (12%) had diseases (vitamin B12 and folic acid deficiencies, hypothyroidism, Parkinson's disease) that could contribute to a dementia diagnosis. Of the remaining 92 demented participants, 46 (50%) had 1 one or more cerebro- or cardiovascular diseases known to be risk factors in the development of dementia. The prevalence of these risk factors was the same in demented and nondemented participants, whereas hypertension was significantly more frequent in nondemented than demented participants. Dementia is common but not inevitable in centenarians. Cerebro- and cardiovascular diseases are equally common in demented and nondemented persons.

Age Distribution↗
PubMed2001

The Danish 1905 cohort: a genetic-epidemiological nationwide survey.

OBJECTIVES: The authors studied nonagenarians, a rapidly growing age group whose cognitive and physical abilities have yet to be investigated systematically. METHODS: All Danes born in 1905 were invited to participate in a home-based 2-hour multidimensional interview, including cognitive and physical performance tests and collection of DNA, carried out by lay interviewers. Population-based registers were used to evaluate representativeness. RESULTS: There were 2,262 participants. A total of 1,632 (72%) gave a DNA sample. Participants and nonparticipants were highly comparable with regard to marital status, institutionalization, and hospitalization patterns, but men and rural area residents were more likely to participate. Six months after the survey began, 7.2% of the participants and 11.8% of the nonparticipants had died. DISCUSSION: Despite the known difficulties of conducting surveys among the extremely old, it was possible to conduct a nationwide survey, including collection of DNA, among more than 2,000 fairly nonselected nonagenarians using lay interviewers.

Aged↗
PubMed2000

X-linked genetic factors regulate hematopoietic stem-cell kinetics in females.

X inactivation makes females mosaics for 2 cell populations, usually with an approximate 1:1 distribution. Skewing of this distribution in peripheral blood cells is more common among elderly women. The depletion of hematopoietic stem cells followed by random differentiation may explain the acquired skewing with age. However, an animal model suggests that selection processes based on X-linked genetic factors are involved. We studied peripheral blood cells from 71 monozygotic twin pairs aged 73 to 93 years and from 33 centenarians, and we found that with age, 1 of the cell populations becomes predominant for most women. We also observed a strong tendency for the same cell line to become predominant in 2 co-twins. This suggests that X-linked genetic factors influence human hematopoietic stem cell kinetics. The fact that females have 2 cell lines with different potentials could be one of the reasons women live longer than men.

Aged↗
PubMed2000

Estimation of apolipoprotein E genotype-specific relative mortality risks from the distribution of genotypes in centenarians and middle-aged men: apolipoprotein E gene is a "frailty gene," not a "longevity gene".

We developed a method to estimate genotype-specific average relative mortality risk, R, from genotype distributions in cross-sectional studies of people belonging to different age-groups, and applied the method to new data from a study of apolipoprotein E genotypes (apoE) in 177 Danish centenarians and data from a study of 40-year-old Danish men. Twenty-one percent of the centenarians were epsilon 2-carriers (genotypes epsilon 2 epsilon 2 and epsilon 3 epsilon 2) and 15% were epsilon 4-carriers (genotypes epsilon 4 epsilon 4 and epsilon 4 epsilon 3) compared to 13 and 29%, respectively, of the young men. The R-values were 0.95 (95% CI 0.88 to 1.02) for epsilon 2-carriers and 1.13 (95% CI 1.05 to 1.22) for epsilon 4-carriers, using epsilon 3 epsilon 3- and epsilon 4 epsilon 2 genotypes as reference. Corresponding values for epsilon 4-carriers were obtained by using published data from a French and a Finnish study of centenarians, whereas the values for epsilon 2-carriers were about 0.90 with these data. The method to estimate mortality risk and the results associate with the view that the apoE gene is a "frailty gene." On the other hand, if odds ratios are used to summarize data from studies of this kind, they are more impressive and may propagate the misconception that apoE is a "longevity gene".

Adult↗
PubMed2000

Virulence variability of the Drosophila C virus and effects of the microparasite on demographic parameters of the host (Drosophila melanogaster).

We carried out experiments with the Drosophila C virus (DCV), a nonhereditary virus acting on demographic parameters of infected Drosophila host populations. It is well known that DCV increases mortality rate, decreases developmental time, and increases daily fecundity. As usual for Drosophila viruses, the DCV was multiplied in vivo. In this study we tested the hypothesis of virulence variability in DCV strains by isolating different stocks of the virus. The flies were tested for susceptibility to injection of such isolates and for virulence variability. Possible interactions between demographic parameters in three Drosophila host populations and injected isolates were studied under two egg densities (low and high). The hypothesis of virulence variability of DCV was supported by significant differences in mortality rates, depending on whether virus isolates were ingested or injected. When DCV was ingested, differences between host mortality rates were independent of the Drosophila host populations. Nevertheless, the developmental time was equally decreased by each virus isolate, independent of the host population. Moreover, the two viral stocks strongly increased the egg production of the flies. This experimental approach clearly showed that DCV could be considered a polymorphic virus. The phenotypic interactions between DCV and host flies varied according to parasite genotype.

Animals↗