Cause of death in mild cognitive impairment: a prospective study (NEDICES).

BACKGROUND AND PURPOSE: Previous studies have reported the occurrence of increased mortality rates among individuals with mild cognitive impairment (MCI), but possible links between MCI subtypes and cause-specific mortality need to be explored. To examine short-term mortality (5 years), long-term mortality (13 years) and cause-specific mortality of individuals over 65 years of age suffering from MCI compared with cognitively unimpaired individuals in the Neurological Disorders in Central Spain (NEDICES) cohort. METHODS: Mild cognitive impairment was classified using standardized psychometric and functional assessment in accordance with diagnostic convention. Cox's proportional hazards models, adjusted by sociodemographics and comorbidity factors, were used to assess the risk of death at 5 and 13 years of MCI subtypes compared with a reference group of older people without cognitive impairment (N = 2329). Causes of death were obtained from the National Population Register of Spain. RESULTS: There were 1484 deceased individuals at 13 years. MCI subtypes were defined as amnestic single domain (N = 259), amnestic multiple domain (N = 197) and non-amnestic (N = 641). After adjusting for covariates, only the amnestic multiple domain MCI subtype showed an increased hazard ratio (HR) for mortality at 5 years versus the reference group. However, the HR for mortality at 13 years was increased for all MCI subtypes. The HR by MCI subtype was 1.19 in the non-amnestic subtype (95% CI 1.05-1.36), 1.31 in the amnestic single domain subtype (95% CI 1.10-1.56) and 1.67 in the amnestic multiple domain subtype (95% CI 1.38-2.02). In terms of cause-specific mortality, the chance of death from dementia was statistically higher in all MCI subtypes. CONCLUSION: Amnestic multiple domain MCI showed the greatest risk of mortality in comparison with other MCI subtypes at different intervals. Dementia was the only cause-specific mortality that was increased in MCI individuals.

Consistency of clinical diagnosis of dementia in NEDICES: A population-based longitudinal study in Spain.

BACKGROUND: Few longitudinal studies have verified the clinical diagnosis of dementia based on clinical examinations. We evaluated the consistency of the clinical diagnosis of dementia over a period of 3 years of follow-up in a population-based, cohort study of older people in central Spain. METHODS: Individuals (N = 5278) were evaluated at baseline (1994-1995) and at follow-up (1997-1998). The evaluation included a screening questionnaire for dementia and a neurological assessment. RESULTS: Dementia screening consisted of a 37-item version of the Mini-Mental State Examination (MMSE) and the Pfeffer Functional Activities Questionnaire (FAQ). Study neurologists investigated those participants who screened positively (N = 713) as well as 843 who had screened negatively to test the sensitivity of the screening instruments or because they had a positive screening for other chronic neurological diseases. We detected 295 patients among those who screened positive and 13 among those who screened negatively. Three years follow-up evaluation demonstrated 14 diagnostic errors at baseline (4.5%) leading to a final number of 306 patients with dementia. The corrected prevalence of dementia was 5.8% (95% confidence interval [CI] 5.2-6.5). CONCLUSIONS: The diagnosis of dementia was highly accurate in this population-based, Spanish cohort study, and our prevalence figures agree with other European surveys. Given the high cost and difficulties of population rescreening and its relatively low yield, we conclude that a single 2-phase investigation (screening followed by clinical examination) provides accurate information for most population-based prevalence studies of dementia.

Phytoseiid mites (Acari: Phytoseiidae) from Chile, with descriptions of three new species and a redescription of Chileseius camposi.

A total of 40 phytoseiid species has been reported from Chile, including the two species (Neoseiulus californicus (McGregor) and Phytoseiulus persimilis (Athias-Henriot) most widely used worldwide for the biological control of the two-spotted spider mite, Tetranychus urticae Koch (Tetranychidae). In this paper we report nine other species found in new collecting conducted since 1989, including three new species: Amblyseius herbicolus (Chant), Amblyseius tamatavensis Blommers, Arrenoseius robertogonzalezi Trincado Martin n. sp., Neoseiulus anonymus (Chant Baker), Neoseiulus bicaudus (Wainstein), Neoseiulus viticolus Trincado Martin n. sp., Metaseiulus (Metaseiulus) camelliae (Chant Yoshida-Shaul), Metaseiulus (Metaseiulus) neoflumenis Moraes Kreiter and Metaseiulus (Metaseiulus) relictus Trincado Martin n. sp.. Chileseius camposi Gonzalez Schuster, 1962 is redescribed, and a list of all species presently known from Chile and a key to help in their separation are given. A new name, Proprioseiopsis kargi Trincado nom. nov., is a replacement name for Proprioseiopsis globosus Karg, 1976, a junior homonym of Proprioseiopsis globosus (Gonzalez Schuster, 1962).

[Serum pro-oxidant and antioxidant factors and risk of Parkinson's disease: population study]. / Factores prooxidantes y antioxidantes séricos y riesgo para enfermedad de Parkinson: estudio poblacional.

INTRODUCTION: Several studies suggested a role of 'oxidative stress' (increased production of prooxidants, antioxidants deficiencies or both) in the pathogenesis of Parkinson's disease. In this study we have measured the serum levels of a number of prooxidant and antioxidant substances to evaluate their possible relation with the risk for Parkinson's disease. PATIENTS AND METHODS: We assessed the serum levels of iron, ferritin, ansferrin, ceruloplasmine, vitamin A, alpha-carotene, beta-carotene, and alpha-tocopherol, in 28 patients with Parkinson's disease and 85 matched controls. All of them were recruited from a population study. RESULTS: None of the values studied differed significantly between the two study groups, and none of them were correlated with age at onset, duration of the disease, scores of the Unified Parkinson Disease Rating Scale or the Hoehn and Yahr staging in the Parkinson's disease group. CONCLUSIONS: These results confirm the previous findings of classic case-control studies, suggesting the absence of relationship of the studied values with the risk for Parkinson's disease.

Cumulative effect of depression on dementia risk.

Objective. To analyze a potential cumulative effect of life-time depression on dementia and Alzheimer's disease (AD), with control of vascular factors (VFs). Methods. This study was a subanalysis of the Neurological Disorders in Central Spain (NEDICES) study. Past and present depression, VFs, dementia status, and dementia due to AD were documented at study inception. Dementia status was also documented after three years. Four groups were created according to baseline data: never depression (nD), past depression (pD), present depression (prD), and present and past depression (prpD). Logistic regression was used. Results. Data of 1,807 subjects were investigated at baseline (mean age 74.3, 59.3% women), and 1,376 (81.6%) subjects were evaluated after three years. The prevalence of dementia at baseline was 6.7%, and dementia incidence was 6.3%. An effect of depression was observed on dementia prevalence (OR [CI 95%] 1.84 [1.01-3.35] for prD and 2.73 [1.08-6.87] for prpD), and on dementia due to AD (OR 1.98 [0.98-3.99] for prD and OR 3.98 [1.48-10.71] for prpD) (fully adjusted models, nD as reference). Depression did not influence dementia incidence. Conclusions. Present depression and, particularly, present and past depression are associated with dementia at old age. Multiple mechanisms, including toxic effect of depression on hippocampal neurons, plausibly explain these associations.

Selective memory impairment on an adapted Mini-Mental State Examination increases risk of future dementia.

OBJECTIVE: To determine whether selective memory impairment (SMI) on an adapted Mini-Mental State Examination (aMMSE) test increases risk of future dementia in a population-based survey of central Spain. BACKGROUND: SMI is a strong predictor of dementia in the elderly. However, most approaches have used extensive memory batteries, which are not always suitable for screening purposes. METHODS: The basal cohort consisted of 2982 poorly educated individuals aged 65 or over. Dementia, stroke and parkinsonism cases were previously excluded. At entry, participants received a structured interview including an aMMSE. Two groups were created according to basal cognitive performance, namely: (1) aMMSE > 23 and no word remembered on the aMMSE delayed-recall task (SMI group); and (2) aMMSE > 23 and at least one word remembered on the delayed-recall task (control group). In a three-year follow-up wave, conversion rate to dementia was calculated and logistic regression was performed. RESULTS: Of a total of 2507 subjects who completed the two evaluations, 280 qualified for SMI at entry. In the SMI group, 25 subjects (8.9%) developed dementia vs 26 subjects (1.2%) in the control group. Taking the two groups together, and once demographic and medical variables had been controlled, a low delayed-recall score increased dementia conversion rate (OR 0.47, 95% CI 0.34-0.64). Alzheimer's disease was the main cause of dementia (79.8%). CONCLUSIONS: Memory impairment is a risk factor for future dementia in the neurologically-healthy elderly. This can be observed in a subgroup of subjects with SMI defined on the aMMSE delayed-recall subscore. Some other measurements should be added to the SMI construct to improve its predictive validity.

Incidence of Parkinson disease and parkinsonism in three elderly populations of central Spain.

BACKGROUND: A two-phase investigation method (screening followed by detailed examination) is the most accurate epidemiologic approach to estimate the epidemiology of Parkinson disease (PD) and secondary parkinsonism. The scarcity of statistics on the incidence of PD and other types of parkinsonism using this methodology led the authors to estimate them in three elderly populations. METHODS: A Spanish elderly parkinsonism-free cohort was followed for an average of 3 years. At the end of the follow-up, the cohort survivors were contacted by way of screening and clinical examination. RESULTS: The cohort consisted of 5,160 subjects (ages 65 to 85 and over): Eight hundred twenty-eight died before the examination, 3,685 completed the screening procedure, and 647 could not be screened because they refused (108) or were unreachable (539). Sixty-eight incident cases of parkinsonism were found: 30 PD (44.1%), 22 drug-induced parkinsonism (32.3%), 8 parkinsonism with associated features (11.7%), and 3 vascular parkinsonism (4.4%). The remaining five cases (7.3%) were classified as unspecified parkinsonism. Average annual incidence rate (per 100,000 person-years) in the population aged 65 to 85 and over years, adjusted to the standard European population, was 409.9 (95% CI 299.0 to 520.8) for parkinsonism and 186.8 (95% CI 110.4 to 263.2) for PD. Incidence rates of parkinsonism increased with advancing age. For PD, incidence rates increased with age in men but decreased beyond the age of 79 in women. Age-adjusted relative risk in men compared with women was 1.56 (95% CI 0.97 to 2.51) for parkinsonism and 2.55 (95% CI 1.21 to 5.37) for PD. Sixteen (53.3%) patients with PD were detected through the screening and had not been diagnosed previously. CONCLUSIONS: Incidence estimates of PD based on two-phase investigation methodology are higher than those based on other approaches. Men had a risk of developing PD that was twice that of women. A large proportion of PD patients may never seek neurologic attention.

Methods and demographic findings of the baseline survey of the NEDICES cohort: a door-to-door survey of neurological disorders in three communities from Central Spain.

OBJECTIVE: To describe the methods and general results of the baseline longitudinal survey in a defined cohort of elderly people from three areas of Central Spain (urban and rural). The survey was designed to study dementia, essential tremor, Parkinson's disease and stroke. STUDY DESIGN: A population-based longitudinal study with door-to-door interviews. METHODS: This study was carried out in two phases: Phase 1 (health status questionnaire and screening performed by lay interviewers) and Phase 2 (diagnosis of neurological illnesses by neurologists). RESULTS: The study flow chart, screening instruments for neurological disorders, main demographic data (age, sex, educational attainment, occupation) and general health status of the 5,278 screened participants (2,238 men and 3,040 women) are given for the two phases. The response rate was 85.3%, and participation was higher in men and in the urban area. CONCLUSIONS: Participation rates were good in both phases of the NEDICES baseline study, and this was influenced by age, sex and setting of the participants. Educational attainment, occupation and health status data are analogous to other Spanish studies performed in the elderly. As the study population was large and good participation rates were achieved, precise analysis of morbidity of the neurological disorders investigated will be possible.