Walking and Talking as Predictors of Falls in the General Population: The Leiden 85-Plus Study

OBJECTIVES

To compare the value of dual tasking in predicting falling in the general population of oldest old with that of easy-to-administer single tasks.

DESIGN

Prospective population-based follow-up study.

SETTING

Municipality of Leiden, the Netherlands.

PARTICIPANTS

Representative cohort of 380 individuals, all aged 85 at baseline.

MEASUREMENTS

During enrollment, walking time over a 12-meter distance was measured, as well as the verbal fluency to recite names of animals or professions during a 30-second period. In the dual task, performance was assessed when participants combined walking with reciting names. Incidence of falls and fractures was assessed by interviewing participants and checking their medical histories.

RESULTS

After 1 year of follow-up, 42% of the participants reported one or more falls, and 4% suffered a fracture. Total walking time, number of steps, and verbal fluency were all strongly related to incident falls (P for trend for all <.01), but dual-task performance was not a better predictor for incident falls than single-task performance.

CONCLUSION

The dual-task test in this study had no predictive value above that of a single-task test to predict falling. Dual tasks with more-sensitive measures of impaired dual-task execution might have better test characteristics. In this study, history of falls and performance on an easy-to-administer single walking task identified old persons at higher risk for falling who could benefit from fall preventive strategies.

High-density vs low-density lipoprotein cholesterol as the risk factor for coronary artery disease and stroke in old age

BACKGROUND

A high total serum cholesterol level does not carry a risk of cardiovascular mortality among people 85 years and older and is related to decreased all-cause mortality. At this old age, there are few data on fractionated lipoprotein levels in the determination of cardiovascular disease risk. The aim of this study was to evaluate the relationships between low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol levels and mortality from specific causes among people in the oldest age categories.

METHODS

Between September 1, 1997, and September 1, 1999, a total of 705 inhabitants in the community of Leiden, the Netherlands, reached the age of 85 years. Among these old people, we initiated a prospective follow-up study to investigate determinants of successful aging. A total of 599 subjects participated (response rate, 87%) and all were followed up to September 2001. Serum levels of total, LDL, and HDL cholesterol were assessed at baseline along with detailed information on comorbid conditions. The main outcome measure was all-cause and specific mortality risk.

RESULTS

During 4 years of follow-up, 152 subjects died. The leading cause of death was cardiovascular disease, with similar mortality risks in all tertiles of LDL cholesterol level. In contrast, low HDL cholesterol level was associated with a 2.0-fold higher risk of fatal cardiovascular disease (95% confidence interval [CI], 1.2-3.2). The mortality risk of coronary artery disease was 2.0 (95% CI, 1.0-3.9) and for stroke it was 2.6 (95% CI, 1.0-6.6). Both low LDL cholesterol and low HDL cholesterol concentrations were associated with an increased mortality risk of infection: 2.7 (95% CI, 1.2-6.2) and 2.4 (95% CI, 1.1-5.6), respectively. The risks were unaffected by comorbidity.

CONCLUSION

In contrast to high LDL cholesterol level, low HDL cholesterol level is a risk factor for mortality from coronary artery disease and stroke in old age.

Living with epilepsy: long-term prognosis and psychosocial outcomes

OBJECTIVE

To analyze the impact of seizures on everyday life and the long-term effects of epilepsy on health status and psychosocial outcomes.

METHODS

Follow-up study was conducted of a cohort of consecutive patients newly diagnosed with epilepsy between 1953 and 1967. In 1995 (mean follow-up 34 years), a random sample of 333 patients received a questionnaire asking clinical and demographic information and validated measures for psychosocial outcomes. Comparisons were made with the general Dutch population.

RESULTS

The response rate was 73% (116 men and 127 women); mean age was 49.9 years (SD 11.2 years). Mean age at epilepsy onset was 15 years (SD 11 years); mean duration was 24.4 years (SD 13.1 years). In total, 134 (55%; 72 men and 62 women) patients were seizure-free for the previous 5 years, and 81 patients still had seizures in the last year. One hundred twenty-seven patients were taking antiepileptic drugs, of which 51 were on monotherapy. Epilepsy patients have a positive health evaluation, comparable with the general Dutch population. Fewer epilepsy patients married or had children than the general Dutch population; more patients live at home with their parents or in foster homes or institutions (p < 0.001). Having epilepsy at school age has a significant negative effect on learning achievement (p < 0.01). Employment status is affected less, though more epilepsy patients are unfit to work than individuals from the general population (p < 0.05).

CONCLUSIONS

Epilepsy has a marked negative impact on education and achievement in later life. Despite worse psychosocial outcomes than the Dutch population, patients with epilepsy cope well with their epilepsy, regardless of their handicaps.

Association of the -2849 interleukin-10 promoter polymorphism with autoantibody production and joint destruction in rheumatoid arthritis

OBJECTIVE

To analyze the -2849 A/G interleukin-10 (IL-10) promoter polymorphism, which is associated with high (AG/GG) and low (AA) IL-10 production, in a cohort of rheumatoid arthritis (RA) patients and controls in order to gain a better understanding of its role in the incidence and progression of RA.

METHODS

Allele frequencies of the promoter polymorphism -2849 A/G and carriage rates were compared in 283 RA patients, 413 patients with other rheumatic diseases, and 1,220 healthy controls. The rate of joint damage and baseline levels of IgG and IgM rheumatoid factors and anti-citrullinated peptide antibodies were measured and were correlated with the IL-10 gene polymorphism. Furthermore, the correlation between the invasiveness of fibroblast-like synoviocytes (FLS) and the -2849 IL-10 genotype was tested.

RESULTS

The IL-10 genotype was not associated with the incidence of RA, but instead, correlated with disease progression, as determined by the extent of joint destruction. A higher rate of joint destruction was observed in patients with the genotype associated with high IL-10 production. Since FLS are thought to be involved in joint destruction, we analyzed IL-10 genotypes in conjunction with FLS invasiveness. Although adenoviral gene transfer of IL-10 to FLS inhibited their invasiveness, no differences were observed in vitro in the FLS from RA patients who were -2849 non-G carriers compared with those who were G carriers. Instead, patients with the -2849 AG/GG genotype, which is associated with high IL-10 production, had higher autoantibody titers at baseline.

CONCLUSION

The -2849 IL-10 promoter polymorphism is associated with autoantibody production and subsequent joint damage in RA.

Evidence for non-random distribution of Fcgamma receptor genotype combinations

Human IgG receptors (FcgammaR) display considerable heterogeneity, and are crucial immune response modulating molecules. FcgammaRIIA, FcgammaRIIIA, and FcgammaRIIIB display functional biallelic polymorphisms. FcgammaR polymorphisms have been found associated with susceptibility to infectious and autoimmune diseases. Linked transmission of FcgammaR alleles was studied by determining the distribution of FcgammaRIIA-FcgammaRIIIA-FcgammaRIIIB genotype combinations in 514 Dutch Caucasian, and 149 Japanese blood donors. The structure of the FcgammaR locus was studied by radiation hybrid mapping of FcgammaRIA, FcgammaRIIA, FcgammaRIIB, FcgammaRIIIA, FcgammaRIIIB, and adjacent genes from the pentraxin family. In addition, crossing-over frequencies within the FcgammaR locus were determined in 63 Dutch Caucasian families, encompassing 183 individuals. FcgammaRII and FcgammaRIII subclasses were mapped in close proximity (0.47-3.14 cR). Accordingly, crossing-over frequencies within the FcgammaRII-III locus in Dutch families were low. Analysis of combined FcgammaR genotypes strongly suggested non-random distribution of FcgammaRIIA-FcgammaRIIIA-, and FcgammaRIIIA-FcgammaRIIIB genotypes in Dutch donors (P<0.001 and P<0.00001, respectively), and of FcgammaRIIA-FcgammaRIIIb genotypes in Japanese blood donors (P<0.02). Frequencies of FcgammaRII-FcgammaRIII haplotypes differed significantly between Dutch and Japanese (P<0.00001). This study provides important information for the interpretation of studies reporting associations of FcgammaR alleles with disease, and underscores the apparent differences in FcgammaR heterogeneity between ethnic groups.

Seroreactivity to epidermodysplasia verruciformis-related human papillomavirus types is associated with nonmelanoma skin cancer

DNA from epidermodysplasia verruciformis-related human papillomavirus (EV-HPV) types is frequently found in nonmelanoma skin cancer (squamous and basal cell carcinoma). Epidemiological studies that investigate the relation between EV-HPV infection and nonmelanoma skin cancer are scarce. We designed a case-control study in which we looked for HPV infection in 540 cases with a history of skin cancer and 333 controls. By measuring seroreactivity to L1 virus-like particles of EV-HPV types 5, 8, 15, 20, 24, and 38 and the genital type HPV16 and by estimating the skin cancer relative risk among HPV seropositives, we analyzed whether EV-HPV serorecognition is associated with nonmelanoma skin cancer. Seroreactivity to five of the six EV-HPV types tested (HPV5, 8, 15, 20, and 24) was significantly increased in the squamous cell carcinoma cases. After adjusting for age and sex, the estimated squamous cell carcinoma relative risk was significantly increased in HPV8 and HPV38 seropositives [odds ratio (OR) = 14.7 (95% confidence interval (CI), 1.6-135) and OR = 3.0 (95% CI, 1.1-8.4), respectively]. The estimated relative risk for nodular and superficial multifocal basal cell carcinoma was also significantly increased in the HPV8 seropositives [OR = 9.2 (95% CI, 1.1-78.2) and OR = 17.3 (95% CI, 2.1-143), respectively] and in the HPV20 seropositives [OR = 3.2 (95% CI 1.3-7.9) and OR = 3.4 (95% CI 1.2-9.5), respectively]. The relative risk of developing malignant melanoma was not increased among HPV seropositives, and no associations were found for HPV16. Restricted analyses among the HPV seropositives only, to exclude distortion by interindividual differences in seroresponsiveness, underscored the significance of our findings. Restricted analyses among patients with skin cancer only, however, revealed that EV-HPV seropositivity was not significantly more present in patients with nonmelanoma skin cancer than in those with melanoma skin cancer. Taken together, our results indicate that EV-HPV serorecognition is nonspecifically associated with nonmelanoma skin cancer and suggest that EV-HPV-directed seroresponses are induced upon skin cancer formation, rather than upon infection.

Predicting kidney graft failure using time-dependent renal function covariates

Chronic rejection and recurrent disease are the major causes of late graft failure in renal transplantation. To assess outcome, most researchers use Cox proportional hazard analysis with time-fixed covariates. We developed a model adding time-dependent renal function covariates to improve the prediction of late graft failure. We studied 692 kidney transplants at the Leiden University Medical Center that had functioned for at least 6 months. Graft failure from chronic rejection or recurrent disease occurred in 106 patients. The reciprocal of last recorded serum creatinine (RC), the ratio of RC and RC at 6 months (RC6), and the time elapsed since last observation (TEL) were used as time-dependent covariates. Cadaveric donor transplantation, a lower RC, and a lower ratio of RC/RC6 were independently associated with graft failure. The impact of the last recorded RC was dependent on its value, TEL, and the time since transplantation. Validation of the model confirmed much higher failure predictions in those with subsequent graft failure compared with nonfailures. This study illustrates that the prediction of late graft failure could be improved significantly by using time-dependent renal function covariates.

Effect of smoking and sun on the aging skin

Smoking and ultraviolet radiation are known to have a detrimental effect on human skin. Important characteristics of the aging skin are elastosis and telangiectasia. The purpose of the study was to assess the relative importance of age per se, and the detrimental effects caused by sun exposure and smoking on the development of cutaneous elastosis and telangiectasia in a well-defined group of individuals. We made use of 966 individuals who participated in a case-control study to investigate environmental and genetic risk factors for skin cancer. Exposure measurements for sunlight and smoking were collected and the amount of elastosis and telangiectasia in the face and neck was recorded according to a four-graded score varying from none to severe. Relative risks were estimated using exposure odds ratios from cross-tabulation and logistic regression. Multivariate logistic regression was used to adjust for potential confounders. Among both sexes a strong association was observed between increasing age, sun exposure, and amount of elastosis. The association between increasing age, sun exposure, and amount of telangiectasia was strong among men, but less apparent among women. Smoking was also associated with elastosis among both sexes, and with telangiectasia predominantly among men. Intrinsic differences between men and women (e.g., hormones) or behavior differences (e.g., more frequent use of creams and cosmetics among women) could account for this apparent difference in the occurrence of telangiectasia. In contrast to elastosis, telangiectasia may not be a good marker of the aging skin, specifically not in women.

[Osteoporosis in elderly women should always be treated, despite the new professional guideline from the Dutch Institute for Health Care Improvement (CBO)]

According to the Dutch Institute for Healthcare Improvement [Dutch acronym: CBO] professional guideline 'Osteoporosis' (second revision), the treatment of osteoporosis should be based on the patient's age because bone loss at an advanced age is thought to be partly physiological. It is recommended that women < 70 years old are treated if the bone mineral density T-score is below -2.5. For women > or = 70 years of age, a lower cut-off point has been chosen, i.e. a Z-score below -1. However, bone strength is dependent on bone mineral density and the fracture risk doubles if the bone mineral density decreases by one standard deviation. Therefore at an advanced age, any bone loss experienced increases the fracture risk, whether or not the mineral loss is physiological. Moreover, most elderly people carry additional risk factors that increase fracture risk. Therefore in women > or = 70 years of age, the treatment of osteoporosis should be considered if the T-score is below -2.5. In this situation, use of the Z-score is not appropriate.

A common variant of the methylenetetrahydrofolate reductase gene (1p36) is associated with an increased risk of cancer

Folate metabolism is thought to play an important role in carcinogenesis through its involvement in both DNA methylation and nucleotide synthesis. A common Ala(222)/Val variant in the methylenetetrahydrofolate reductase (MTHFR) gene leads to a disturbed folate metabolism and is associated with decreased genomic DNA methylation. We previously reported that the MTHFR Val/Val genotype was associated with increased cancer mortality in men from a population-based cohort of subjects ages > or = 85 years. To further explore the deleterious effects of the MTHFR genotype, we studied the association of the genotype with cancer risk in 860 men ages 65-84 years who were followed >10 years (Zutphen Elderly Study). During follow-up, 149 new cases of cancer occurred among the 793 men without cancer at baseline. The risk of developing cancer was 1.80-fold (95% confidence interval, 1.09-3.00) higher among men with the Val/Val genotype than among men with the Ala/Ala genotype. Except for lung cancer [relative risk (RR), 1.15], the risks of common forms of cancers were significantly increased among men with the Val/Val genotype [cancer of the prostate (RR, 3.48); the colorectum (RR, 3.65); the kidney and bladder (RR, 5.48)]. The risks of cancer were particularly increased among men with a lower folate and a higher alcohol intake and men of an older age. In conclusion, our current and previous studies in two independent populations indicate that a common Ala/Val variant in the MTHFR gene is a risk factor for cancer in elderly men from the general population. The mechanism underlying this association might involve genomic instability as a result of insufficient methylation of genomic DNA.

Atherosclerosis and cognitive impairment are linked in the elderly. The Leiden 85-plus Study

Post-mortem analyses suggest that atherosclerosis more often contributes to late-onset dementia than hitherto expected. We set out to further unravel the relation between atherosclerosis and cognitive impairment. We therefore tested the hypothesis that the number of cardiovascular pathologies is positively associated with cognitive impairment in elderly subjects, and that the smaller number of cardiovascular pathologies in women explains the better cognitive function of elderly women. Within the Leiden 85-plus Study, we assessed the atherosclerotic burden by counting the number of cardiovascular pathologies in the medical histories of a population-based sample of 599 subjects aged 85 years (response 87%). Significantly more men than women had a history of cardiovascular pathologies (67% compared to 59%, P<0.001). In addition, cognitive function was assessed. All subjects completed the Mini-Mental State Examination (MMSE). Cognitive speed and memory were determined with specific neuro-psychological tests in those with a MMSE-score above 18 points. There was a highly significant dose-response relationship between the number of cardiovascular pathologies and cognitive impairment for both men and women. The median MMSE-score was 26 points in subjects without cardiovascular disease and decreased to 25 points for subjects who had two or more cardiovascular pathologies (P for trend =0.003). Similar associations were found for cognitive speed but not for memory. Our data confirm that in old age atherosclerosis significantly contributes to cognitive impairment. Since treatments for atherosclerosis appear to be particularly effective in elderly people, we consider our finding of utmost clinical importance in possibly preventing cognitive impairment and late-onset dementia.

Pravastatin in elderly individuals at risk of vascular disease (PROSPER): a randomised controlled trial

BACKGROUND

Although statins reduce coronary and cerebrovascular morbidity and mortality in middle-aged individuals, their efficacy and safety in elderly people is not fully established. Our aim was to test the benefits of pravastatin treatment in an elderly cohort of men and women with, or at high risk of developing, cardiovascular disease and stroke.

METHODS

We did a randomised controlled trial in which we assigned 5804 men (n=2804) and women (n=3000) aged 70-82 years with a history of, or risk factors for, vascular disease to pravastatin (40 mg per day; n=2891) or placebo (n=2913). Baseline cholesterol concentrations ranged from 4.0 mmol/L to 9.0 mmol/L. Follow-up was 3.2 years on average and our primary endpoint was a composite of coronary death, non-fatal myocardial infarction, and fatal or non-fatal stroke. Analysis was by intention-to-treat.

FINDINGS

Pravastatin lowered LDL cholesterol concentrations by 34% and reduced the incidence of the primary endpoint to 408 events compared with 473 on placebo (hazard ratio 0.85, 95% CI 0.74-0.97, p=0.014). Coronary heart disease death and non-fatal myocardial infarction risk was also reduced (0.81, 0.69-0.94, p=0.006). Stroke risk was unaffected (1.03, 0.81-1.31, p=0.8), but the hazard ratio for transient ischaemic attack was 0.75 (0.55-1.00, p=0.051). New cancer diagnoses were more frequent on pravastatin than on placebo (1.25, 1.04-1.51, p=0.020). However, incorporation of this finding in a meta-analysis of all pravastatin and all statin trials showed no overall increase in risk. Mortality from coronary disease fell by 24% (p=0.043) in the pravastatin group. Pravastatin had no significant effect on cognitive function or disability.

INTERPRETATION

Pravastatin given for 3 years reduced the risk of coronary disease in elderly individuals. PROSPER therefore extends to elderly individuals the treatment strategy currently used in middle aged people.

A high response is not essential to prevent selection bias: results from the Leiden 85-plus study

We tested the hypothesis that an additional effort to increase the response rate would diminish selection bias in a community-based cohort study. In the Leiden 85-plus Study, all subjects of the town of Leiden who had reached their 85th birthday were informed of the study by mail and then asked to participate by telephone. In an additional recruitment stage, those subjects who did not participate directly were visited and personally asked to participate. When these subjects refused, some nonresponse questions were asked. In this way we collected data on the whole source population. Of 691 eligible elderly subjects, 511 subjects (74%) participated directly. Of those who did not participate directly, 88 subjects participated after the additional effort. The response rate increased from 74% to 87%. Compared to the 511 subjects who directly participated, the 88 subjects who entered the study after the additional effort had poorer health and lower survival. The subjects who refused were more healthy and had poorer mood. The direct sample did not differ from the source population with respect to socio-demographics, health, and mortality. In conclusion, we showed that given a moderately high direct response the additional effort was effective in increasing the response rate, but was also selective and was not necessary to prevent selection bias.

Cognitive decline in AD and mild cognitive impairment is associated with global brain damage

OBJECTIVE

To investigate the relationships between structural damage in the whole brain, the temporal lobes, and the frontal lobes and cognitive decline at old age. The authors hypothesized that widespread brain damage as quantified using magnetization transfer imaging (MTI) is related to global cognitive decline, whereas regional damage to the temporal lobes is related to memory impairment, and regional damage to the frontal lobes is related to executive dysfunctioning.

METHODS

Cognitive function of 22 patients with probable AD, 13 patients with mild cognitive impairment (MCI), and 28 elderly controls was assessed using an extensive neuropsychological test battery. Structural damage in the whole brain, the temporal lobes, and the frontal lobes was estimated using volumetric MTI analysis. Associations between MTI measures and neuropsychological tests were investigated using Pearson correlation analysis.

RESULTS

MTI measures of the whole brain, as well as the temporal and the frontal lobes, were strongly associated with global cognitive deterioration and impairment in memory, orientation, language, praxis, gnosis, and executive functioning. However, there were no specific cognitive correlates of regional brain damage to the temporal and frontal lobes.

CONCLUSIONS

Using whole brain volumetric magnetization transfer imaging, the authors demonstrated that cognitive decline in patients with mild cognitive impairment and AD is associated with widespread structural brain damage. As there were no specific relationships between regional brain damage and impairment of specific cognitive functions, pathology in AD and mild cognitive impairment is much more generalized than was expected.

No increase in mortality and morbidity among carriers of the C282Y mutation of the hereditary haemochromatosis gene in the oldest old: the Leiden 85-plus study

BACKGROUND

The C282Y mutation in the gene for haemochromatosis (HFE) has been associated with various diseases at middle age. However, recent studies indicate that penetrance of the C282Y mutation is low. We explored the association between the C282Y mutation, iron metabolism, and morbidity and mortality in participants of the Leiden 85-plus.

STUDY DESIGN

A cross-sectional comparison and prospective follow-up was conducted in two unselected cohorts of 661 and 552 subjects. All subjects were aged 85 years and over. We determined the prevalence of C282Y homozygous and heterozygous subjects, and the association between the C282Y mutation and iron metabolism, all-cause and specific causes of death.

RESULTS

Prevalence of C282Y homozygosity in both cohorts was 0.2% (1/661 and 1/552, respectively) and of C282Y heterozygosity was 12.4% (82/661) and 11.4% (63/552), respectively. These estimates coincide exactly with reported estimates in younger age groups. Median ferritin level was 97 microg L-1 (IQR 39-162) for heterozygous carriers and 89 microg L-1 (IQR 41-157) for noncarriers (P = 0.66). The serum ferritin concentration for one C282Y homozygous subject, a woman aged 86 years at the time of enrollment in 1986, was 392 microg L-1. Cardiovascular morbidity was comparable between the C282Y heterozygous subjects and the noncarriers in both study cohorts. All-cause and cardiovascular mortality of carriers of the C282Y mutation was similar to that in noncarriers.

CONCLUSIONS

We found two C282Y homozygous subjects, illustrating that homozygosity can be compatible with survival in very old ages. C282Y heterozygosity was not associated with history of cardiovascular disease morbidity, all cause mortality, cardiovascular mortality, or biochemical phenotype of haemochromatosis at old age.

Evidence for additional genetic risk indicators of relapse-onset MS within the HLA region

BACKGROUND

Human leukocyte antigen (HLA)-DR2 carriership is associated with an increased risk for MS. Genome searches using microsatellite markers have consistently shown that additional genetic factors contribute to susceptibility for MS.

OBJECTIVE

To identify loci within the HLA region that predispose to relapse-onset MS independently of HLA-DR2.

METHOD

A case-control study involving 159 patients with definite relapse-onset MS and 273 control subjects was conducted. Six highly polymorphic microsatellite markers encoded within the HLA-C to DR region, that is, D6S1014, D6S273, TNFa, MIB, C1_2_5, and C1_3_2, three single-nucleotide tumor necrosis factor (TNF) promoter gene polymorphisms at positions -238, -308, and -376, and HLA-DR2 carriership were typed.

RESULTS

These data confirmed the well-known association between the HLA-DR2 haplotype and relapse-onset MS, yielding an odds ratio (OR) of 3.6 (95% CI: 2.4 to 5.4; p < 0.0001). Multivariate analyses revealed that C1_3_2*354 was also associated with an increased risk for developing relapse-onset MS independently of HLA-DR2 (OR: 2.0; 95% CI: 1.2 to 3.1; p = 0.004). This allele is encoded within an ancestral haplotype that is highly linked to HLA-DR3. The joint effect of this ancestral haplotype and HLA-DR2 resulted in an OR of 8.7 (95% CI: 2.7 to 29; p < 0.0001) to develop relapse-onset MS. In addition, a protective risk factor was found: carriers of TNFa*107 had a 0.5-fold lower risk to develop relapse-onset MS (95% CI: 0.3 to 0.9; p = 0.026).

CONCLUSION

Within the HLA region, other loci besides HLA-DR2 haplotype modulate susceptibility for relapse-onset MS.

Common chronic diseases and general impairments as determinants of walking disability in the oldest-old population

OBJECTIVES

Walking disability affects older people's autonomy and well-being. We investigated the relative effect of common chronic diseases and general impairments on walking disability in the general oldest-old population.

DESIGN

Population-based cohort study.

SETTING

Leiden 85-plus Study, the Netherlands.

PARTICIPANTS

Five hundred ninety-nine persons aged 85, response rate 87%.

MEASUREMENTS

Walking disability was assessed using a 6-meter walking test. Persons with a walking time below the 25th percentile and those who were physically unable to perform the walking test were categorized as having a walking disability. Information on common chronic diseases was obtained from records of subjects' general practitioners and pharmacies. General impairments were assessed with functional tests and standardized questions during face-to-face interviews. We expressed the effect of common chronic diseases and general impairments as the population attributable risk (PAR), indicating how much disability can be prevented when the identified risk factor is eliminated from the population.

RESULTS

One hundred ninety-two persons (33%) had a walking disability. This disability was highly associated with poor mobility in daily life, recurrent falls, and poor well-being (all P <.001). Of the common chronic diseases, stroke, angina pectoris, diabetes mellitus, and hip fracture but not arthritis contributed most (PARs from 6% to 15%) to walking disability in the population at large. General impairments had higher prevalence rates and higher PARs than common chronic diseases. Cognitive impairment, depressive symptoms, and dizziness upon rising contributed most (PARs between 22 to 27%) to walking disability. In multivariate regression analyses of all common chronic diseases and general impairments, associations remained significant.

CONCLUSION

Within the general oldest-old population, general impairments contribute more substantially to walking disability than do common chronic diseases. The diagnosed diseases did not explain the impairments that led to walking disability. Especially in the oldest old, clinicians should focus not merely on common chronic diseases but particularly on general impairments as targets for diagnostic analysis and treatment to decrease walking disability.

The prognosis of depression in old age: outcome six to eight years after clinical treatment

Previous studies suggest that the short-term outcome in severely depressed elderly in The Netherlands is worse compared to other studies in the Western world. The present study examines the long-term prognosis of hospitalized elderly patients with major depressive disorder and possible predictors of outcome. One hundred and five elderly inpatients with unipolar major depression, admitted by regional mental health services in a geographically delimited area, were evaluated six to eight years after index episode by trained residents using a structured diagnostic interview (C.I.D.I.) The GP was interviewed using a standard questionnaire. At follow-up 40% of the original sample had died. Of the survivors 33% had fared well, 24% had a relapsing course, 22% had residual symptoms, 11% were continuously ill, and 9% had probable dementia. With respect to prognostic factors, personality disorder predicted a worse outcome. All patients with a major depressive disorder at follow-up received specialised care and used antidepressants. None of the patients received ECT. The mortality rate in clinically treated elderly with major depressive disorder is high. Among survivors the long-term prognosis in The Netherlands is comparable with other studies to date. The presence of a personality disorder predicts worse outcome. Though the accessibility of services seems to be good, more vigorous treatment was not applied.

Magnetization transfer imaging in normal aging, mild cognitive impairment, and Alzheimer's disease

The purpose of this study was to assess whether structural brain damage as detected by volumetric magnetization transfer imaging (MTI) is present in mild cognitive impairment (MCI) and Alzheimer's disease (AD) and, if so, whether these abnormalities are global in character or restricted to the temporal lobe. Volumetric MTI analysis of the whole brain and temporal and frontal lobes was performed in 25 patients with probable AD, in 13 patients with MCI, and in 28 controls. Magnetization transfer ratio (MTR) histograms were produced, from which we derived measures for structural brain damage and atrophy. The peak heights of the MTR histograms of MCI and AD patients were lower than those of controls for the whole brain and temporal and frontal lobes, reflecting structural brain damage. AD patients had more atrophy than controls in all regions that were studied. MCI patients differed from controls for temporal lobe atrophy only. Volumetric MTI demonstrates structural changes that are related to cognitive decline in large parts of the brain of AD patients. Moreover, structural changes also were observed in MCI patients, indicating that widespread brain damage can be demonstrated before patients are clinically demented.

Association between high-density lipoprotein and cognitive impairment in the oldest old

Low high-density lipoprotein cholesterol is associated with an increased risk for cardiovascular disease and stroke. At the same time, cardiovascular disease and stroke are important risk factors for dementia. We assessed the association between total and fractionated cholesterol and cognitive impairment and explored whether observed associations were dependent on or independent of atherosclerotic disease. In a population-based study, total cholesterol, triglycerides, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol were measured in 561 subjects 85 years old and grouped in three equal strata representing decreasing serum concentrations. History of cardiovascular disease and stroke was determined. All subjects completed the Mini-Mental State Examination (MMSE), and the presence of dementia was determined. Median MMSE scores were significantly lower in subjects with low high-density lipoprotein cholesterol (25 points vs 27 points, p < 0.001). No differences in MMSE scores were found for other lipids and lipoproteins. MMSE scores in subjects with and without cardiovascular disease were 26 and 27 points (p = 0.007), respectively, and in subjects with and without stroke were 21 and 26 points (p < 0.001), respectively. The associations between low MMSE scores and low high-density lipoprotein cholesterol remained significant after subjects with cardiovascular disease or stroke were excluded. In a comparison of subjects with low high-density lipoprotein cholesterol with subjects with high high-density lipoprotein cholesterol, the odds ratio for dementia was 2.3 (95% confidence interval, 1.2-4.3), and in subjects without cardiovascular disease or stroke, it was 3.7 (95% confidence interval, 1.3-10.1). All odds ratios were unaffected by education, low-density lipoprotein cholesterol, triglycerides, and survival. Low high-density lipoprotein cholesterol is associated with cognitive impairment and dementia. At least part of the association between high-density lipoprotein cholesterol and cognitive function is independent of atherosclerotic disease.

Association of the tumour necrosis factor alpha -308G/A polymorphism with the risk of diabetes in an elderly population-based cohort

Ample evidence supports a role for tumour necrosis factor alpha (TNFalpha) in the development of type 2 diabetes and cardiovascular disease. TNFalpha expression was found to be influenced by a -308G/A polymorphism in the promoter of the gene encoding TNFalpha (TNF). We investigated the contribution of this polymorphism to diabetes and cardiovascular mortality in a population-based cohort of 664 subjects aged 85 years and over (Leiden 85-plus Study). The -308G/A TNF promoter polymorphism was associated with the prevalence of diabetes in old age (P = 0.006). The risk of diabetes among subjects homozygous for the A-allele was estimated to be 4.6-fold (95% CI, 1.6-13.3) higher than among subjects homozygous for the common G-allele. The promoter polymorphism did not, however, predict mortality from all causes, cardiovascular diseases, cancer or infectious diseases during a 10-year follow-up period. In addition to the promoter polymorphism, TNFa and TNFc microsatellite genotypes were determined but these polymorphisms were not associated with morbidity or mortality. In conclusion, the -308G/A polymorphism in the TNF promoter is strongly associated with the risk of diabetes but not cardiovascular mortality in old age.

Production of IL-1beta and IL-1Ra as risk factors for susceptibility and progression of relapse-onset multiple sclerosis

Interleukin-1beta (IL-1beta) is present in multiple sclerosis (MS) lesions. Interleukin-1 receptor antagonist (IL-1Ra) moderates the induction of experimental autoimmune encephalomyelitis (EAE). Here, we show that families that are characterized by high IL-1beta over IL-1Ra production ratio are at 2.2-fold (95% CI, 1.0-4.8; p=0.05) increased risk to have a patient relative with relapse-onset MS than families with a low ratio. It is also related to the reduction of volumetric magnetization transfer ratio (MTR) histogram height, a measure of parenchymal integrity (p=0.04). Those families who combine a high IL-1beta over IL-1Ra ratio with a high tumor necrosis factor (TNF) over IL-10 production ratio have a 6.2-fold (95% CI, 1.8-21; p=0.002) increased risk. Innate production of IL-1beta and IL-1Ra is not related to the outcome of primary progressive MS. Taq1 polymorphism in the IL-1beta gene and the variable number of tandem repeats (VNTR) polymorphism of 86-base pairs within the IL-1Ra gene cannot explain these findings.

Leiden research program on ageing

Research into ageing is among the priorities of the Leiden University Medical Center. Several tight collaborations between basic and clinical departments are the basis of this program. Our focus is to identify determinants of human longevity and disease at old age with an emphasis on inflammation, atherosclerosis, and cognitive decline. To this end we enroll a large series of long-lived families for genetic screening, prospectively follow large cohorts of old people dependent on various genetic and environmental risk factors, and perform randomized controlled trials in the general population testing plausible hypotheses how interventions can maximize rewarding lifespans.

Low production capacity of interleukin-10 associates with the metabolic syndrome and type 2 diabetes : the Leiden 85-Plus Study

It has been suggested that the metabolic syndrome and type 2 diabetes are manifestations of the inflammatory host response. This host response is orchestrated by the production of pro- and anti-inflammatory cytokines that are under genetic control. We therefore hypothesized that a low production capacity of interleukin-10 (IL-10), a centrally operating cytokine with strong anti-inflammatory properties, associates with the metabolic syndrome and type 2 diabetes in old age. In the current study, 599 inhabitants of the city of Leiden, age 85 years, were visited at their place of residence. The production capacity of the anti-inflammatory cytokine IL-10 was assessed in a whole-blood assay in which lipopolysaccharide was used as a stimulus. Serum concentrations of lipids, lipoproteins, glucose, and HbA(1c) were determined, and a history of type 2 diabetes was obtained. Serum concentrations of total cholesterol, LDL cholesterol, triglycerides, glucose, and HbA(1c) gradually decreased over strata representing higher IL-10 production capacity, whereas the concentration of HDL cholesterol gradually increased (all P < 0.01). The odds ratio for type 2 diabetes was 2.7 (95% confidence interval 1.5-4.9) when subjects with the lowest IL-10 production capacity were compared with those with the highest IL-10 production capacity. These findings showed that low IL-10 production capacity (i.e., a pro-inflammatory response) is associated with the metabolic syndrome and type 2 diabetes.

Survival of patients with epilepsy: an estimate of the mortality risk

PURPOSE

To investigate the extent and causes of the differences in mortality found in studies on mortality in epilepsy based on a quantitative review of the literature.

METHODS

We used MEDLINE database and Cumulative Index Medicus for 1960-2001, Excerpta Medica for 1948-1965, and relevant journals and bibliographies. We selected comparative studies investigating mortality in epilepsy patients conducted in the last 100 years. The Standardized Mortality Ratio (SMR) was selected as primary outcome. Nineteen studies were included. Pooled estimates were precision weighted and tested for homogeneity. Sources of variability between risk estimates were explored by using multivariate fixed-effects models.

RESULTS

SMRs ranged from 1.3 to 9.3. Risk estimates proved heterogeneous (chi-square test statistic: 1,177; df = 18; p < 0.001). The most important determinant was "source population," explaining half of the variance of the estimates (R(2), 0.47; p = 0.006). SMRs in community studies ranged from 1.3 to 3.1, and for institutionalized populations, from 1.9 to 5.1.

CONCLUSIONS

Our results show that the mortality risk in patients with epilepsy is dependent on source population of patients. Within the different source populations, considerable unexplained variance remains. Hence no uniform summary estimate for the elevated mortality could be determined.

Inflammation and stroke: the Leiden 85-Plus Study

BACKGROUND

Experimental evidence indicates that interleukin-10 (IL-10) deficiency is associated with the development of cardiovascular and cerebrovascular disease. We analyzed the relation between low IL-10 production levels, history of stroke, and incident fatal stroke.

SUMMARY OF REPORT

All 85-year-old inhabitants of Leiden, Netherlands (n=599) were visited at their place of residence (response rate, 87%). Production levels of the anti-inflammatory cytokine IL-10 were assessed in a whole blood assay whereby lipopolysaccharide was used as a stimulus. Plasma concentrations of C-reactive protein (CRP) were also used as a marker of inflammation. A history of stroke was obtained at baseline (prevalence, 10%). The number of fatal strokes was prospectively obtained for a median follow-up of 2.6 years (incidence, 1.82 per 100 person-years at risk). Subjects with a history of stroke had significantly lower median IL-10 production levels at baseline than subjects without stroke (558 versus 764 pg/mL; P<0.05). They also had significantly higher median CRP concentrations (6 versus 3 mg/L; P<0.05). The odds ratio for a history of stroke increased to 2.30 (95% CI, 1.12 to 4.72) over strata representing decreasing production levels of IL-10. The relative risk for incident fatal stroke was 2.94 (95% CI, 1.01 to 8.53) when we compared subjects with low or intermediate baseline IL-10 production levels to those with high production levels of IL-10.

CONCLUSIONS

Our data support the hypothesis that subjects with low IL-10 production levels have an increased risk of stroke.

Frequency of functional interleukin-10 promoter polymorphism is different between relapse-onset and primary progressive multiple sclerosis

Interleukin-10 (IL-10) secretion affects the inducibility of experimental autoimmune encephalomyelitis and the outcome of multiple sclerosis (MS). Here, we report that a G to A polymorphism in the IL-10 promoter at position -2849 is significantly associated with low IL-10 production. The frequency of this polymorphism is lower among patients with primary progressive compared with patients with relapse-onset MS and control persons.

Nitric oxide mediates hypoxia-induced cerebral vasodilation in humans

Nitric oxide (NO) plays a pivotal role in the regulation of peripheral vascular tone. Its role in the regulation of cerebral vascular tone in humans remains to be elucidated. This study investigates the role of NO in hypoxia-induced cerebral vasodilatation in young healthy volunteers. The effect of the NO synthase inhibitor N(G)-monomethyl-L-arginine (L-NMMA) on the cerebral blood flow (CBF) was assessed during normoxia and during hypoxia (peripheral O(2) saturation 97 and 80%, respectively). Subjects were positioned in a magnetic resonance scanner, breathing normal air (normoxia) or a N(2)-O(2) mixture (hypoxia). The CBF was measured before and after administration of L-NMMA (3 mg/kg) by use of phase-contrast magnetic resonance imaging techniques. Administration of L-NMMA during normoxia did not affect CBF. Hypoxia increased CBF from 1,049 +/- 113 to 1,209 +/- 143 ml/min (P < 0.05). After L-NMMA administration, the augmented CBF returned to baseline (1,050 +/- 161 ml/min; P < 0.05). Similarly, cerebral vascular resistance declined during hypoxia and returned to baseline after administration of L-NMMA (P < 0.05 for both). Use of phase-contrast magnetic resonance imaging shows that hypoxia-induced cerebral vasodilatation in humans is mediated by NO.

Polymorphisms in or near tumour necrosis factor (TNF)-gene do not determine levels of endotoxin-induced TNF production

Innate differences in tumour necrosis factor (TNF) production have been associated with susceptibility for and outcome of inflammatory diseases. Several studies have tried to identify whether polymorphisms in or near the TNF gene or other markers on the short arm of chromosome 6 (6p21) are related to differences in TNF production. Data on these associations are conflicting. Therefore, we conducted a study among 129 healthy individuals in which TNF production was determined upon stimulation with endotoxin in whole blood cultures. TNFa microsatellite, TNF single nucleotide polymorphisms at position +489, -238, -308 and -376 typing was performed. The data revealed that alleles of TNFa microsatellite and carriership of TNF polymorphisms were not related to TNF production. We conclude that the genes determing the differences in endotoxin-induced TNF production have not been yet identified.

Association of APOE epsilon2/epsilon3/epsilon4 and promoter gene variants with dementia but not cardiovascular mortality in old age

The common apolipoprotein E (APOE) alleles epsilon2, epsilon3, and epsilon4 are associated with the risk of dementia and cardiovascular disease. Recently, two functional variants (- 219G/T and -491A/T) were identified in the promoter of the APOE gene that enable a further characterization of the role of the APOE locus in disease. We investigated the contribution of these APOE gene variants to dementia and cardiovascular mortality in old age using a population-based cohort of 648 subjects aged 85 years and over (Leiden 85-Plus Study). Genotypes containing an APOE epsilon4 allele were associated with a 4.1-fold (95% CI, 2.2-7.7) increased risk of dementia as compared to the epsilon3/epsilon3 genotype in old subjects. Moreover, homozygosity for the -219T allele was found to be associated with a 2.4-fold (95% CI, 1.0-5.8) increased risk independently of epsilon2 and epsilon4; the -491A/T variant was not associated with dementia. Over a 10-year follow-up period, the risk of cardiovascular mortality was not increased among epsilon4 carriers (RR, 0.6; 95% CI, 0.4-1.0) or -219T homozygous subjects (RR, 1.1; 95% CI, 0.7-1.7), nor did it decrease among -491T homozygous subjects (RR, 1.4; 95% CI, 0.6-3.1). In conclusion, both the APOE epsilon2/epsilon3/epsilon4 and the -219G/T variant were identified as risk factors for dementia but not cardiovascular mortality in old age. Our results support the hypothesis that both the isoform and the amount of APOE may influence the risk of dementia. Furthermore, they emphasize that variation at the APOE locus has a higher impact on the risk of dementia than on the risk of cardiovascular disease in old age.

Cardiovascular side effects of inhaled salbutamol in hypoxic asthmatic patients

BACKGROUND

Beta-2 adrenoceptor agonists have been associated with sudden death in asthma patients but the cause and underlying mechanism are unclear. Animal experiments indicate that the combination of hypoxia and β2 agonists may result in detrimental cardiovascular effects. A study was undertaken to investigate the effect of hypoxia on the systemic vascular effects of salbutamol in patients with asthma who are hypoxic by assessing forearm blood flow (FBF) as a measure of peripheral vasodilatation.

METHODS

Eight men with mild asthma underwent the following treatments: normoxia + placebo (NP), normoxia + salbutamol (NS), hypoxia + placebo (HP), and hypoxia + salbutamol (HS). The period of mask breathing started at t=0 minutes, lasted for 60 minutes, and at 30 minutes 800 μg salbutamol was inhaled. The experiment was completed 30 minutes after the inhalation (t=60 minutes). For the hypoxia treatment the Spo2 level was 82%. Differences between treatments were sought using factorial ANOVA on percentage change from the pretreatment value.

RESULTS

There were no significant differences in blood pressure and potassium levels between the treatments. After 60 minutes the increase in FBF was 13% (95% CI –12 to 39) more for HP treatment than for NP, 21% (95% CI –5 to 46) more for NS than for NP, and 32% (95% CI 7 to 58) more for HS than for HP (p=0.016). The inhalation of salbutamol during hypoxia resulted in a significant increase in FBF of 45% (95% CI 20 to 71) compared with NP (p=0.001).

CONCLUSION

Patients with asthma who are hypoxic and inhale β2 agonists have serious systemic vascular side effects which may be an additional explanation for the association between asthma treatment and sudden death.

Innate cytokine profile in patients with complex regional pain syndrome is normal

Complex regional pain syndrome (CRPS) is a disabling disease characterized by the classic symptoms and signs of inflammation. In this study we investigated the innate cytokine profile in patients with CRPS to determine a possible role of the immune system in the pathophysiology of CRPS. The cytokine profile before and after lipopolysaccharide and thrombin stimulation was determined in 26 severely affected CRPS patients and 20 healthy controls. No difference in the production of pro- and anti- inflammatory cytokines between patients and controls was found. Hence, our results do not support a role of genetic factors responsible for the cytokine profile in the pathophysiology of CRPS. These findings encourage further investigations of mechanisms responsible for neurogenic-induced inflammation.