Davide Seripa

Late-life depression, mild cognitive impairment, and dementia: possible continuum?

Clinical and epidemiologic research has focused on the identification of risk factors that may be modified in predementia syndromes, at a preclinical and early clinical stage of dementing disorders, with specific attention to the role of depression. Our goal was to provide an overview of these studies and more specifically to describe the prevalence and incidence of depression in individuals with mild cognitive impairment (MCI), the possible impact of depressive symptoms on incident MCI, or its progression to dementia and the possible mechanisms behind the observed associations. Prevalence and incidence of depressive symptoms or syndromes in MCI vary as a result of different diagnostic criteria and different sampling and assessment procedures. The prevalence of depression in individuals with MCI was higher in hospital-based studies (median: 44.3%, range: 9%-83%) than in population-based studies (median: 15.7%, range: 3%-63%), reflecting different referral patterns and selection criteria. Incidence of depressive symptoms varied from 11.7 to 26.6/100 person-years in hospital-based and population-based studies. For depressed normal subjects and depressed patients with MCI, the findings on increased risk of incident MCI or its progression to dementia were conflicting. These contrasting findings suggested that the length of the follow-up period, the study design, the sample population, and methodological differences may be central for detecting an association between baseline depression and subsequent development of MCI or its progression to dementia. Assuming that MCI may be the earliest identifiable clinical stage of dementia, depressive symptoms may be an early manifestation rather than a risk factor for dementia and Alzheimer disease, arguing that the underlying neuropathological condition that causes MCI or dementia also causes depressive symptoms. In this scenario, at least in certain subsets of elderly patients, late-life depression, MCI, and dementia could represent a possible clinical continuum.

APOE and Alzheimer disease: a major gene with semi-dominant inheritance

Apolipoprotein E (APOE) dependent lifetime risks (LTRs) for Alzheimer Disease (AD) are currently not accurately known and odds ratios alone are insufficient to assess these risks. We calculated AD LTR in 7351 cases and 10 132 controls from Caucasian ancestry using Rochester (USA) incidence data. At the age of 85 the LTR of AD without reference to APOE genotype was 11% in males and 14% in females. At the same age, this risk ranged from 51% for APOE44 male carriers to 60% for APOE44 female carriers, and from 23% for APOE34 male carriers to 30% for APOE34 female carriers, consistent with semi-dominant inheritance of a moderately penetrant gene. Using PAQUID (France) incidence data, estimates were globally similar except that at age 85 the LTRs reached 68 and 35% for APOE 44 and APOE 34 female carriers, respectively. These risks are more similar to those of major genes in Mendelian diseases, such as BRCA1 in breast cancer, than those of low-risk common alleles identified by recent GWAS in complex diseases. In addition, stratification of our data by age groups clearly demonstrates that APOE4 is a risk factor not only for late-onset but for early-onset AD as well. Together, these results urge a reappraisal of the impact of APOE in Alzheimer disease.

Development and Validation of a Multidimensional Prognostic Index for One-Year Mortality from Comprehensive Geriatric Assessment in Hospitalized Older Patients

Our objective was to construct and validate a Multidimensional Prognostic Index (MPI) for 1-year mortality from a Comprehensive Geriatric Assessment (CGA) routinely carried out in elderly patients in a geriatric acute ward. The CGA included clinical, cognitive, functional, nutritional, and social parameters and was carried out using six standardized scales and information on medications and social support network, for a total of 63 items in eight domains. A MPI was developed from CGA data by aggregating the total scores of the eight domains and expressing it as a score from 0 to 1. Three grades of MPI were identified: low risk, 0.0-0.33; moderate risk, 0.34-0.66; and severe risk, 0.67-1.0. Using the proportional hazard models, we studied the predictive value of the MPI for all causes of mortality over a 12-month follow-up period. MPI was then validated in a different cohort of consecutively hospitalized patients. The development cohort included 838 and the validation cohort 857 elderly hospitalized patients. Of the patients in the two cohorts, 53.3 and 54.9% were classified in the low-risk group, respectively (MPI mean value, 0.18 +/- 0.09 and 0.18 +/- 0.09); 31.2 and 30.6% in the moderate-risk group (0.48 +/- 0.09 and 0.49 +/- 0.09); 15.4 and 14.2% in the severe-risk group (0.77 +/- 0.08 and 0.75 +/- 0.07). In both cohorts, higher MPI scores were significantly associated with older age (p = 0.0001), female sex (p = 0.0001), lower educational level (p = 0.0001), and higher mortality (p = 0.0001). In both cohorts, a close agreement was found between the estimated mortality and the observed mortality after both 6 months and 1 year of follow-up. The discrimination of the MPI was also good, with a ROC area of 0.751 (95%CI, 0.70-0.80) at 6 months and 0.751 (95%CI, 0.71-0.80) at 1 year of follow-up. We conclude that this MPI, calculated from information collected in a standardized CGA, accurately stratifies hospitalized elderly patients into groups at varying risk of mortality.

Prevalence, clinical features and avoidability of adverse drug reactions as cause of admission to a geriatric unit: a prospective study of 1756 patients.

AbstractBackground: Drug use increases with advancing age, and in older patients it is associated with an increase in adverse drug reactions (ADRs). ADRs are a primary cause of morbidity and mortality worldwide. Objectives: To evaluate the prevalence, clinical characteristics and avoidability of ADR-related hospital admissions in elderly patients. Methods: From November 2004 to December 2005, all patients aged ≥65 years consecutively admitted to the Geriatric Unit of the Casa Sollievo della Sofferenza Hospital, San Giovanni Rotondo in Italy, were evaluated for enrolment in the study. ADRs were defined according to the WHO Adverse Reaction Terminology system. Drugs were classified according to Anatomical Therapeutic Chemical classification system. The Naranjo algorithm was used to evaluate the relationship between drug use and the ADR (definite, probable, possible or doubtful) and Hallas criteria were used to evaluate the avoidability of the ADR (definitely avoidable, possibly avoidable or unavoidable). All cases of a suspected ADR were discussed by a team trained in drug safety, including three geriatricians, one clinical pharmacologist and one pharmacist. Only cases of an ADR with an agreement ≥80% were included. Results: Of the 1756 patients observed, 102 (5.8%, 42 males, 60 females, mean age 76.5 ± 7.4 years, range 65–93 years) showed certain (6.8%) or probable (91.2%) ADR-related hospitalization. Gastrointestinal disorders (48 patients, 47.1%); platelet, bleeding and clotting disorders (20 patients, 19.6%); and cardiovascular disorders (13 patients, 12.7%) were the most frequent ADRs. NSAIDs (23.5%), oral anticoagulants (20.6%), low-dose aspirin (acetylsalicylic acid) [13.7%] and digoxin (12.7%) were the drugs most frequently involved in ADRs. Of the ADRs, 45.1% were defined as definitely avoidable, 31.4% as possibly avoidable, 18.6% as unavoidable and 4.9% as unclassifiable. Of 78 patients with definitely or possibly avoidable ADRs, 17 patients (21.8%) had received an inappropriate prescription, 29 patients (37.2%) had not received a prescription for an effective gastroprotective drug concomitantly with NSAID or low-dose aspirin treatment and 32 patients (41%) were not monitored during drug treatment. Conclusion: In the elderly, almost 6% of hospitalizations are ADR related. Most of these ADRs are potentially avoidable. Strategies that reduce inappropriate prescriptions and monitoring errors, as well as improving active prevention of ADRs, are needed in elderly subjects.

Diet and Alzheimer’s disease risk factors or prevention: the current evidence

Preventing or postponing the onset of Alzheimer’s disease (AD) and delaying or slowing its progression would lead to a consequent improvement of health status and quality of life in older age. Elevated saturated fatty acids could have negative effects on age-related cognitive decline and mild cognitive impairment (MCI). Furthermore, at present, epidemiological evidence suggests a possible association between fish consumption, monounsaturated fatty acids and polyunsaturated fatty acids (PUFA; in particular, n-3 PUFA) and a reduced risk of cognitive decline and dementia. Poorer cognitive function and an increased risk of vascular dementia (VaD) were found to be associated with a lower consumption of milk or dairy products. However, the consumption of whole-fat dairy products may be associated with cognitive decline in the elderly. Light-to-moderate alcohol use may be associated with a reduced risk of incident dementia and AD, while for VaD, cognitive decline and predementia syndromes, the current evidence is only suggestive of a protective effect. The limited epidemiological evidence available on fruit and vegetable consumption and cognition generally supports a protective role of these macronutrients against cognitive decline, dementia and AD. Only recently, higher adherence to a Mediterranean-type diet was associated with decreased cognitive decline, although the Mediterranean diet (MeDi) combines several foods, micro- and macro-nutrients already separately proposed as potential protective factors against dementia and predementia syndromes. In fact, recent prospective studies provided evidence that higher adherence to a Mediterranean-type diet could be associated with slower cognitive decline, reduced risk of progression from MCI to AD, reduced risk of AD and a decreased all-cause mortality in AD patients. These findings suggested that adherence to the MeDi may affect not only the risk of AD, but also of predementia syndromes and their progression to overt dementia. Based on the current evidence concerning these factors, no definitive dietary recommendations are possible. However, following dietary advice for lowering the risk of cardiovascular and metabolic disorders, high levels of consumption of fats from fish, vegetable oils, nonstarchy vegetables, low glycemic index fruits and a diet low in foods with added sugars and with moderate wine intake should be encouraged. Hopefully this will open new opportunities for the prevention and management of dementia and AD.

Nonrandom Distribution of Aberrant Promoter Methylation of Cancer-Related Genes in Sporadic Breast Tumors

Purpose: In an effort to additionally determine the global patterns of CpG island hypermethylation in sporadic breast cancer, we searched for aberrant promoter methylation at 10 gene loci in 54 primary breast cancer and 10 breast benign lesions. Experimental Design: Genomic DNA sodium bisulfate converted from benign and malignant tissues was used as template in methyl-specific PCR for BRCA1, p16, ESR1, GSTP1, TRβ1, RARβ2, HIC1, APC, CCND2, and CDH1 genes. Results: The majority of the breast cancer (85%) showed aberrant methylation in at least 1 of the loci tested with half of them displaying 3 or more methylated genes. The highest frequency of aberrant promoter methylation was found for HIC1 (48%) followed by ESR1 (46%), and CDH1 (39%). Similar methylation frequencies were detected for breast benign lesions with the exception of the CDH1 gene (P = 0.02). The analysis of methylation distribution indicates a statistically significant association between methylation of the ESR1 promoter, and methylation at CDH1, TRβ1, GSTP1, and CCND2 loci (P < 0.03). Methylated status of the BRCA1 promoter was inversely correlated with methylation at the RARβ2 locus (P < 0.03). Conclusions: Our results suggest a nonrandom distribution for promoter hypermethylation in sporadic breast cancer, with tumor subsets characterized by aberrant methylation of specific cancer-related genes. These breast cancer subgroups may represent separate biological entities with potential differences in sensitivity to therapy, occurrence of metastasis, and overall prognosis.

Nutraceutical properties of Mediterranean diet and cognitive decline: possible underlying mechanisms.

Recent prospective studies provided evidence that higher adherence to a Mediterranean-type diet could be associated with slower cognitive decline, reduced risk of progression from mild cognitive impairment to Alzheimers disease (AD), reduced risk of AD, and decreased mortality in AD patients. Furthermore, the Mediterranean diet (MeDi) combines several foods, micro- and macronutrients already separately proposed as potential protective factors against dementia and predementia syndromes. At present, epidemiological evidence suggests a possible association between fish consumption, monounsaturated fatty acids, and polyunsaturated fatty acids (PUFA) (particularly, n-3 PUFA), and reduced risk of cognitive decline and dementia. Light to moderate alcohol use may be associated with a reduced risk of incident dementia and AD, while for vascular dementia, cognitive decline, and predementia syndromes, the current evidence is only suggestive of a protective effect. Finally, the limited epidemiological evidence available on fruit and vegetable consumption and cognition generally support a protective role of these macronutrients against cognitive decline, dementia, and AD. We reviewed evidence on the possible mechanisms underlying the suggested protective role of MeDi against age-related changes in cognitive function, predementia syndromes, and dementia, examining the possible role of macronutrients and food nutrients of the MeDi and their nutraceutical properties in modulating the risk of cognitive decline. Although vascular variables are likely to be in the causal pathway between MeDi and dementia syndromes and should be considered as possible mediators, other nonvascular biological mechanisms (i.e., metabolic, oxidative, and inflammatory) may be invoked to explain the complex epidemiological association between MeDi and cognitive decline.

Metabolic Syndrome and Cognitive Impairment: Current Epidemiology and Possible Underlying Mechanisms

A possible role of vascular and lifestyle-related factors was recently proposed for age-related changes of cognitive function, predementia syndromes, and cognitive decline of degenerative (Alzheimers disease, AD) or vascular origin (vascular dementia, VaD). At present, cumulative evidence suggests that vascular risk factors may be important in the development of mild cognitive impairment (MCI), dementia, and AD. Among vascular-related factors, metabolic syndrome (MetS) has been associated with the risk of cognitive decline, overall dementia, and VaD, but contrasting findings also existed on the possible role of MetS in AD. If MetS is associated with increased risk of developing cognitive impairment, regardless of mechanism, then early identification and treatment of these individuals at risk might offer new avenues for disease-course modification. Strategies towards early and effective risk factor management could be of value in reducing risk of metabolic and cognitive decline. Future research is needed to confirm the association between MetS and cognitive impairment and to determine the exact mechanism linking them. Such would provide important insights into the causes and interdependencies of predementia and dementia syndromes, and inspire novel strategies for treating and preventing these disorders. At present, vascular risk factor and MetS management could be employed to delay the onset of dementia syndromes or to prevent the progression of predementia syndromes. In the future, trials could be undertaken to determine whether modifications of these risk factors, including inflammation, could lower risk of developing cognitive decline.

Prevalence of Apolipoprotein E Alleles in Healthy Subjects and Survivors of Ischemic Stroke An Italian Case-Control Study

BACKGROUND AND PURPOSE The epsilon4 allele of the apolipoprotein E (apoE) has been related to the occurrence of myocardial infarction, but its association with ischemic stroke is controversial. We have evaluated the relation between apoE alleles and the occurrence of cerebrovascular ischemia. METHODS The apoE epsilon genotypes of 100 patients with a documented history of ischemic stroke without clinically apparent dementia (stroke+) and 108 subjects without such history (stroke-) were determined. The relative frequency of the apoE alleles and genotypes was estimated in 398 healthy subjects aged < 40 years from the same ethnic background. RESULTS The frequency of the apoE epsilon4 allele in stroke+ (0.18 [95% CI, 0.12 to 0.25]) was higher than in stroke- (0.07 [95% CI, 0.03 to 0.12]; P<.001) or in healthy subjects (0.09 [95% CI, 0.07 to 0.12]; P<.001). Carriers of the epsilon4 allele differed between stroke+ (0.30 [95% CI, 0.19 to 0.42]) and stroke- (0.12 [95% CI, 0.5 to 0.22]; P=.004) or healthy subjects (0.16 [95% CI; 0.12 to 0.22]; P=.015). Accordingly, epsilon3/epsilon3 homozygotes were less frequent in stroke+ (0.59 [95% CI, 0.45 to 0.71]) than in stroke- (0.72 [95% CI, 0.59 to 0.82]; P=.063) or in healthy subjects (0.73 [95% CI, 0.67 to 0.78]; P=.01). In a multiple logistic regression analysis, age (P<.03), positive family history (P<.04) and apoE (P<.002) independently contributed to a stroke history, with epsilon4 carriers exhibiting a higher estimated risk (odds ratio, 5.05). CONCLUSIONS Our data show an association between apoE gene and a personal history of ischemic stroke and support the possibility that the apoE gene is a susceptibility locus for the risk of cerebrovascular ischemic disease.

Immunotherapy for Alzheimer's disease: from anti-β-amyloid to tau-based immunization strategies.

The exact mechanisms leading to Alzheimers disease (AD) are largely unknown, limiting the identification of effective disease-modifying therapies. The two principal neuropathological hallmarks of AD are extracellular β-amyloid (Aβ), peptide deposition (senile plaques) and intracellular neurofibrillary tangles containing hyperphosphorylated tau protein. During the last decade, most of the efforts of the pharmaceutical industry were directed against the production and accumulation of Aβ. The most innovative of the pharmacological approaches was the stimulation of Aβ clearance from the brain of AD patients via the administration of Aβ antigens (active vaccination) or anti-Aβ antibodies (passive vaccination). Several active and passive anti-Aβ vaccines are under clinical investigation. Unfortunately, the first active vaccine (AN1792, consisting of preaggregate Aβ and an immune adjuvant, QS-21) was abandoned because it caused meningoencephalitis in approximately 6% of treated patients. Anti-Aβ monoclonal antibodies (bapineuzumab and solanezumab) are now being developed. The clinical results of the initial studies with bapineuzumab were equivocal in terms of cognitive benefit. The occurrence of vasogenic edema after bapineuzumab, and more rarely brain microhemorrhages (especially in Apo E ε4 carriers), has raised concerns on the safety of these antibodies directed against the N-terminus of the Aβ peptide. Solanezumab, a humanized anti-Aβ monoclonal antibody directed against the midregion of the Aβ peptide, was shown to neutralize soluble Aβ species. Phase II studies showed a good safety profile of solanezumab, while studies on cerebrospinal and plasma biomarkers documented good signals of pharmacodynamic activity. Although some studies suggested that active immunization may be effective against tau in animal models of AD, very few studies regarding passive immunization against tau protein are currently available. The results of the large, ongoing Phase III trials with bapineuzumab and solanezumab will tell us if monoclonal anti-Aβ antibodies may slow down the rate of deterioration of AD. Based on the new diagnostic criteria of AD and on recent major failures of anti-Aβ drugs in mild-to-moderate AD patients, one could argue that clinical trials on potential disease-modifying drugs, including immunological approaches, should be performed in the early stages of AD.