Dietary patterns are related to cognitive functioning in elderly enriched with individuals at increased risk for Alzheimer's disease.

PURPOSE: To investigate cross-sectional associations between dietary patterns and cognitive functioning in elderly free of dementia. METHODS: Data of 389 participants from the German DELCODE study (52% female, 69 ± 6 years, mean Mini Mental State Score 29 ± 1) were included. The sample was enriched with elderly at increased risk for Alzheimer's disease (AD) by including participants with subjective cognitive decline, mild cognitive impairment (MCI) and siblings of AD patients. Mediterranean and MIND diets were derived from 148 Food Frequency Questionnaire items, and data-driven patterns by principal component analysis (PCA) of 39 food groups. Associations between dietary patterns and five cognitive domain scores were analyzed with linear regression analyses adjusted for demographics (model 1), and additionally for energy intake, BMI, other lifestyle variables and APOe4-status (model 2). For PCA-derived dietary components, final model 3 included all other dietary components. RESULTS: In fully adjusted models, adherence to Mediterranean and MIND diet was associated with better memory. The 'alcoholic beverages' PCA component was positively associated with most cognitive domains. Exclusion of MCI subjects (n = 60) revealed that Mediterranean and MIND diet were also related to language functions; associations with the alcoholic beverages component were attenuated, but most remained significant. CONCLUSION: In line with data from elderly population samples, Mediterranean and MIND diet and some data-derived dietary patterns were related to memory and language function. Longitudinal data are needed to draw conclusions on the putative effect of nutrition on the rate of cognitive decline, and on the potential of dietary interventions in groups at increased risk for AD.

Characterization of Cerebellar Atrophy and Resting State Functional Connectivity Patterns in Sporadic Adult-Onset Ataxia of Unknown Etiology (SAOA).

Sporadic adult-onset ataxia of unknown etiology (SAOA) is a non-genetic neurodegenerative disorder of the cerebellum of unknown cause which manifests with progressive ataxia without severe autonomic failure. Although SAOA is associated with cerebellar degeneration, little is known about the specific cerebellar atrophy pattern in SAOA. Thirty-seven SAOA patients and 49 healthy controls (HCs) were included at two centers. We investigated the structural and functional characteristics of SAOA brains using voxel-based morphometry (VBM) and resting-state functional imaging (rs-fMRI). In order to examine the functional consequence of structural cerebellar alterations, the amplitude of low-frequency fluctuation (ALFF) and degree centrality (DC) were analyzed, and then assessed their relation with disease severity, disease duration, and age of onset within these regions. Group differences were investigated using two-sample t tests, controlling for age, gender, site, and the total intracranial volume. The VBM analysis revealed a significant, mostly bilateral reduction of local gray matter (GM) volume in lobules I-V, V, VI, IX, X, and vermis VIII a/b in SAOA patients, compared with HCs. The GM volume loss in these regions was significantly associated with disease severity, disease duration, and age of onset. The disease-related atrophy regions did not show any functional alternations compared with HCs but were functionally characterized by high ALFF and poor DC compared with intact cerebellar regions. Our data revealed volume reduction in SAOA in cerebellar regions that are known to be involved in motor and somatosensory processing, corresponding with the clinical phenotype of SAOA. Our data suggest that the atrophy occurs in those cerebellar regions which are characterized by high ALFF and poor DC. Further studies have to show if these findings are specific for SAOA, and if they can be used to predict disease progression.

Genome-wide significant risk factors for Alzheimer's disease: role in progression to dementia due to Alzheimer's disease among subjects with mild cognitive impairment.

Few data are available concerning the role of risk markers for Alzheimer's disease (AD) in progression to AD dementia among subjects with mild cognitive impairment (MCI). We therefore investigated the role of well-known AD-associated single-nucleotide polymorphism (SNP) in the progression from MCI to AD dementia. Four independent MCI data sets were included in the analysis: (a) the German study on Aging, Cognition and Dementia in primary care patients (n=853); (b) the German Dementia Competence Network (n=812); (c) the Fundació ACE from Barcelona, Spain (n=1245); and (d) the MCI data set of the Amsterdam Dementia Cohort (n=306). The effects of single markers and combined polygenic scores were measured using Cox proportional hazards models and meta-analyses. The clusterin (CLU) locus was an independent genetic risk factor for MCI to AD progression (CLU rs9331888: hazard ratio (HR)=1.187 (1.054-1.32); P=0.0035). A polygenic score (PGS1) comprising nine established genome-wide AD risk loci predicted a small effect on the risk of MCI to AD progression in APOE-ɛ4 (apolipoprotein E-ɛ4) carriers (HR=1.746 (1.029-2.965); P=0.038). The novel AD loci reported by the International Genomics of Alzheimer's Project were not implicated in MCI to AD dementia progression. SNP-based polygenic risk scores comprising currently available AD genetic markers did not predict MCI to AD progression. We conclude that SNPs in CLU are potential markers for MCI to AD progression.

[Advance directive of probands in pharmaceutical research : A medical ethics discussion]. / Probandenverfügung in der Arzneimittelforschung : Eine medizinethische Diskussion.

In the fourth Act on the amendment of pharmaceutical legal and other regulations in November 2016, the legislature has designated the proband advance directive based on the instrument of patient advance directive to enable group beneficial research with persons not capable of giving consent. This article describes the existing conditional need for group beneficial research and presents the problem of the decisive instrument for advance directives at the center of the considerations. The features of the proband advance directive concluded by the legislature stand in opposition to a successful implementation, particularly due to the necessary concrete clarification content far in advance for informed research participants. This article describes solution possiblities, which refer to the realization of the instrument of a proxy research authorization as well as the consideration of an advance research planning based on the advance care planning.

[The importance of molecular imaging (PET) in the diagnostics of dementia]. / Bedeutung molekularer Bildgebung (PET) in der Diagnostik von Demenzerkrankungen.

Due to the expanding older population and increasing prevalence of dementia and currently lacking curative therapy but potentially conceivable availability of molecular-specific treatment to delay the progression of cognitive decline, the early diagnosis of cognitive deficits and their etiological differential diagnosis becomes increasingly more important. The advances in nuclear medicine diagnostics in the field of neurodegenerative diseases within the last few years have been substantial. In this article the relevance of these technologies in the diagnostic process of dementia is described.

[Guideline-adherent inpatient psychiatric psychotherapeutic treatment of behavioral and psychological symptoms of dementia : Normative definition of personnel requirements]. / Leitliniengerechte stationäre psychiatrisch-psychotherapeutische Behandlung psychischer und Verhaltenssymptome bei Demenz : Normative Personalbedarfsermittlung.

BACKGROUND: Dementia is of increasing medical and societal relevance. Hospitalization of dementia patients is mostly due to behavioral and psychological symptoms of dementia (BPSD). There is a need for sufficient qualified personnel in hospitals in order to be able to effectively treat these symptoms. OBJECTIVES: This study aims at identifying the personnel requirements for guideline-conform, evidence-based inpatient treatment concepts for patients with BPSD and to compare these with the resources defined by the German psychiatric personnel regulations (Psych-PV). Furthermore, it was the aim to identify how often patients with dementia received non-pharmacological therapy during inpatient treatment. METHODS: Based on the current scientific evidence for treatment of BPSD, a schedule for a multimodal non-pharmacological treatment was defined and based on this the corresponding personnel requirements were calculated. Using the treatment indicators in psychiatry and psychosomatics (VIPP) database as a reference, it was calculated on what proportion of treatment days patients were classified into G1 according to the German Psych-PV and at least once received more than two treatment units per week. RESULTS: For the implementation of a guideline-oriented and evidence-based treatment plan, a higher need for personnel resources than that provided by the Psych-PV was detected in all areas. Currently patients with dementia who received at least more than two treatment units per week during inpatient hospitalization, were classified into G1 according to German Psych-PV on 17.9 % of treatment days. CONCLUSION: Despite evidence for the efficacy of non-pharmacological treatment measures on BPSD, these forms of treatment cannot be sufficiently provided under the current conditions. The realization of a new quality controlled therapeutic concept is necessary to enable optimized treatment of patients with BPSD.

[Clinical Phenomenology of Autoimmune Encephalitis]. / Klinische Phänomenologie der Autoimmunenzephalitiden.

Antibody-associated disorders of the central nervous system constitute a heterogeneous group of disorders that can be roughly divided into two categories: Classic paraneoplastic syndromes associated with so-called well-characterized antibodies (paraneoplastic neurological disorders, PND) and autoimmune disorders with antibodies to membrane-bound or synaptic antigens (autoimmune encephalitis, AE). The discovery of autoimmune encephalitis has led to a paradigm shift in diagnosis and therapy as well as a reclassification of some neuropsychiatric syndromes that were previously classified as idiopathic or simply covered with descriptive terms.In this review article, especially clinical aspects of autoimmune encephalitis will be discussed, as there has been a rapid increase in knowledge in this regard within the past decade; increasingly overlap syndromes and associations with other disease entities have been detected. In addition to general aspects, characteristics of anti-NMDAR-, anti-LGI1-, anti-GABAA and GABABR, anti-AMPAR-, anti-CASPR2-, anti-mGluR, anti-GlycinR-, anti-GAD, anti- DPPX- and anti-D2 R encephalitis and the anti-IgLON5 encephalopathy will be presented.

[Cognitive Behavioral Therapy and Assertive Community Treatment Reduces Days in Hospital and Delays Hospital Admission in Severe Psychotic Disorders]. / Kognitive Verhaltenstherapie und Assertive Community Treatment reduzieren die Anzahl stationärer Tage und verlängern die Zeit bis zu einer stationären Aufnahme bei schweren psychotischen Störungen.

The primary aim of this study was to assess the effectiveness of integrated home treatment (IV, i. e. intensive cognitive behavioral therapy and pharmacotherapy provided within a framework of assertive community treatment) in individuals with severe mental disorders (n = 13) within the German healthcare system. A treatment-as-usual group (TAU, n = 13) was identified by propensity score matching. Symptoms (CGI), functioning (GAF) and service engagement (SES) were assessed. Quality of life (MSLQ-R) was rated by the IV patients. A reduction of days spent in hospital [IV: 2.3 (6.1); TAU: 33.6 (53.6); Z = 45; p = 0.044], time to admission (IV: 384 days 95% CI 309 - 459.1; TAU: 234.9 days 95% CI 127.2 - 342.5; log rank: Chi-square = 4.31, p < 0.05), severity of the illness (p < 0.01), positive symptoms (p < 0.001), and cognitive symptoms (p < 0.05), as well as functioning (p < 0.05) and service engagement (p < 0.05) was observed in IV patients. Despite differences on a descriptive level, differences in total admissions (IV: 15.3%; TAU: 53.8%; odds ratio = 0.155, 95% CI 0.0243 - 1.00) were not significant. A methodological limitation is that symptom ratings were not performed by independent and blinded raters.

Predictors of hippocampal atrophy in critically ill patients.

BACKGROUND AND PURPOSE: Hippocampal atrophy is presumably one morphological sign of critical illness encephalopathy; however, predictors have not yet been determined. METHODS: The data for this report derived from patients treated at the intensive care units (ICUs) of the University Hospital in Bonn in the years 2004-2006. These patients underwent structural magnetic resonance imaging 6-24 months after discharge. Volumes (intracranial, whole brain, white matter, grey matter, cerebral spinal fluid, bilateral hippocampus) were compared with healthy controls. Pro-inflammatory parameters and ICU scoring systems were explored in conjunction with brain volumes. Cut-scores were defined to differentiate patients with high from those with low inflammatory response. RESULTS: Hippocampal and white matter volume were reduced in critically ill patients compared with healthy controls. Procalcitonin showed a very strong correlation (r = -0.903, P = 0.01) and interleukin-6 a moderate correlation (r = -0.538, P = 0.031) with hippocampal volume, but not with other brain volumes. C-reactive protein was linked to grey matter volume. There was no correlation with systemic inflammatory response syndrome criteria (body temperature, heart rate, respiratory rate, white blood cell count) or for hippocampal or whole brain volume. Furthermore, parameters representing severity of disease (APACHE II score, SOFA score, duration of stay and duration of mechanical ventilation) were not associated with hippocampal or other brain volumes. CONCLUSIONS: This analysis suggests that high levels of procalcitonin and interleukin-6 in the blood serum of critically ill patients are associated with a high likelihood of hippocampal atrophy irrespective of the severity of disease measured by ICU scoring systems and other inflammatory parameters.

Incident subjective memory complaints and the risk of subsequent dementia.

OBJECTIVE: In this study, we aimed to analyze the association between new-incident-subjective memory complaints (SMC) and risk of subsequent dementia in a general population sample aged 75+ years. METHOD: Data were derived from follow-up (FUP) waves I-V of the population-based Leipzig Longitudinal Study of the Aged (LEILA75+). We used the Kaplan-Meier survival method to estimate dementia-free survival times of individuals with and without incident SMC and multivariable Cox proportional hazards regression to assess the association between incident SMC and risk of subsequent dementia, controlled for covariates. RESULTS: Of 443 non-demented individuals, 58 (13.1%) developed dementia during a subsequent 5.4-year follow-up period. Participants with incident SMC showed a significantly higher progression to dementia (18.5% vs. 10.0%; P=0.010) and a significantly shorter mean dementia-free survival time than those without (6.2 vs. 6.8 years; P=0.008). The association between incident SMC and risk of subsequent dementia remained significant in the multivariable Cox analysis (adjusted hazard ratio=1.8; P=0.028). CONCLUSION: Our findings suggest higher progression to dementia and shorter dementia-free survival in older individuals with incident SMC. These findings support the notion that such subjective complaints should be taken seriously in clinical practice as possible early indicators of incipient dementia.

Mortality in incident dementia - results from the German Study on Aging, Cognition, and Dementia in Primary Care Patients.

OBJECTIVE: Dementia is known to increase mortality, but the relative loss of life years and contributing factors are not well established. Thus, we aimed to investigate mortality in incident dementia from disease onset. METHOD: Data were derived from the prospective longitudinal German AgeCoDe study. We used proportional hazards models to assess the impact of sociodemographic and health characteristics on mortality after dementia onset, Kaplan-Meier method for median survival times. RESULTS: Of 3214 subjects at risk, 523 (16.3%) developed incident dementia during a 9-year follow-up period. Median survival time after onset was 3.2 years (95% CI = 2.8-3.7) at a mean age of 85.0 (SD = 4.0) years (≥2.6 life years lost compared with the general German population). Survival was shorter in older age, males other dementias than Alzheimer's, and in the absence of subjective memory complaints (SMC). CONCLUSION: Our findings emphasize that dementia substantially shortens life expectancy. Future studies should further investigate the potential impact of SMC on mortality in dementia.

[Services for the early recognition of psychoses and bipolar disorders in Germany: inventory survey study]. / Angebote zur Früherkennung von Psychosen und bipolaren Störungen in Deutschland: Bestandsaufnahme.

BACKGROUND: In order to successfully implement early recognition and intervention services in psychiatry, it is crucial to improve the attention to and recognition of severe mental disorders and to establish low threshold services that are available at short notice for diagnostic and treatment procedures. MATERIAL AND METHODS: For this inventory survey study, questionnaires regarding the presence and type of early recognition services for psychoses and bipolar disorders were sent separately to German psychiatric hospitals by mail in September and October 2012. Additionally, an internet search and telephone inquiries as well as an alignment of responses from the two surveys and with network lists from published and ongoing early recognition studies were performed. RESULTS: Response rates in the psychosis and bipolar disorder surveys were 21 % (51/246) and 36 % (91/255), respectively. Three quarters of participating institutions reported at least an interest in creating an early recognition service for psychoses and one half for bipolar disorders. Overall, 26 institutions were identified that already offer early recognition of psychoses and 18 of bipolar disorders. Of these 16 are low threshold early recognition centres with direct access at short notice for first-episode patients and person from at-risk groups and separate specific public relations work. Of these early recognition centres five have a separate and easy to find homepage available; in an additional 15 institutions the specific websites are part of the institutions homepage. CONCLUSION: Despite widespread interest and the increasingly recognized importance of early recognition and intervention services in psychiatry, there is currently no nationwide coverage with early recognition services for severe mental disorders in Germany. Public relations and information activities are not (yet) sufficiently provided to reach affected persons and their environment. Common standards are (still) missing and interdisciplinary models are sparse. To correct these shortcomings, amongst other factors, acquisition of sufficient funding for such services is required.

[Treating Late Life Depression with Antidepressants--A Summary of Recommendations in International Guidelines]. / Medikamentöse Behandlung der Depression im Alter--Empfehlungen aus Internationalen Leitlinien und aktueller Literatur.

Late life depression is associated with severe health consequences, e.g. elevated risk of medical comorbidity and decreased quality of life. This paper summarizes the recommendations of the international guidelines on evidence-based pharmacological treatment of depression in late life in a systematic review. Pharmacological treatments for depression recommended by most of the guidelines, however, hardly address the issue of the possible side effects of antidepressants and other factors of multi-medication on the elderly. Different guidelines pay different degrees of attention to the specific group of geriatric patients. There is a lack of evidence-based treatment recommendation that takes into consideration the specific age-related issues of sensitivity to adverse effects or pharmacokinetic interaction. Further research is required to provide a database for more refined recommendations in guidelines.

Apolipoprotein E epsilon 4 genotype and a physically active lifestyle in late life: analysis of gene-environment interaction for the risk of dementia and Alzheimer's disease dementia.

BACKGROUND: As physical activity may modify the effect of the apolipoprotein E (APOE) ε4 allele on the risk of dementia and Alzheimer's disease (AD) dementia, we tested for such a gene-environment interaction in a sample of general practice patients aged ⩾75 years. METHOD: Data were derived from follow-up waves I-IV of the longitudinal German study on Ageing, Cognition and Dementia in Primary Care Patients (AgeCoDe). The Kaplan-Meier survival method was used to estimate dementia- and AD-free survival times. Multivariable Cox regression was used to assess individual associations of APOE ε4 and physical activity with risk for dementia and AD, controlling for covariates. We tested for gene-environment interaction by calculating three indices of additive interaction. RESULTS: Among the randomly selected sample of 6619 patients, 3327 (50.3%) individuals participated in the study at baseline and 2810 (42.5%) at follow-up I. Of the 2492 patients without dementia included at follow-up I, 278 developed dementia (184 AD) over the subsequent follow-up interval of 4.5 years. The presence of the APOE ε4 allele significantly increased and higher physical activity significantly decreased risk for dementia and AD. The co-presence of APOE ε4 with low physical activity was associated with higher risk for dementia and AD and shorter dementia- and AD-free survival time than the presence of APOE ε4 or low physical activity alone. Indices of interaction indicated no significant interaction between low physical activity and the APOE ε4 allele for general dementia risk, but a possible additive interaction for AD risk. CONCLUSIONS: Physical activity even in late life may be effective in reducing conversion to dementia and AD or in delaying the onset of clinical manifestations. APOE ε4 carriers may particularly benefit from increasing physical activity with regard to their risk for AD.

A hierarchy of predictors for dementia-free survival in old-age: results of the AgeCoDe study.

OBJECTIVE: Progression from cognitive impairment (CI) to dementia is predicted by several factors, but their relative importance and interaction are unclear. METHOD: We investigated numerous such factors in the AgeCoDe study, a longitudinal study of general practice patients aged 75+. We used recursive partitioning analysis (RPA) to identify hierarchical patterns of baseline covariates that predicted dementia-free survival. RESULTS: Among 784 non-demented patients with CI, 157 (20.0%) developed dementia over a follow-up interval of 4.5 years. RPA showed that more severe cognitive compromise, revealed by a Mini-Mental State Examination (MMSE) score < 27.47, was the strongest predictor of imminent dementia. Dementia-free survival time was shortest (mean 2.4 years) in such low-scoring patients who also had impaired instrumental activities of daily living (iADL) and subjective memory impairment with related worry (SMI-w). Patients with identical characteristics but without SMI-w had an estimated mean dementia-free survival time of 3.8 years, which was still shorter than in patients who had subthreshold MMSE scores but intact iADL (4.2-5.2 years). CONCLUSION: Hierarchical patterns of readily available covariates can predict dementia-free survival in older general practice patients with CI. Although less widely appreciated than other variables, iADL impairment appears to be an especially noteworthy predictor of progression to dementia.

[Prediction of Alzheimer's dementia]. / Prädiktion der Alzheimer-Demenz.

The prediction of Alzheimer's dementia is relevant for the development and design of prevention trials but also for individual counselling of patients. There are two key characteristics which determine the level of prediction that can be achieved. Firstly, the prevalence of Alzheimer's dementia in the respective setting is important. In low prevalence settings, such as primary care populations, it is probably impossible to achieve positive predictive values above 50%. In high prevalence settings, such as memory clinics, the positive predictive value of Alzheimer's dementia can be much higher. The second major characteristic is the level of cognitive impairment of an individual. The predictive power for Alzheimer's dementia increases from the cognitively healthy status to the status of progressive mild cognitive impairment. Prediction can further be increased by the use of cerebral spinal fluid and brain imaging biomarkers of Alzheimer's disease. The combination of different biomarkers may increase prediction even further. The present article reviews studies and outlines the principles of prediction of Alzheimer's dementia.

[Therapy for patients with dementia. Treatment strategies in the elderly]. / Therapie von Demenzerkrankungen. Behandlungsstrategien im Alter.

BACKGROUND: The number of patients with dementia is increasing. There is often uncertainty about adequate treatment. OBJECTIVES: In this paper, current treatment recommendations for dementia are summarized. MATERIAL AND METHODS: The basis of the article is the S3 guideline on dementia from the Gesellschaft für Psychiatrie und Psychotherapie, Psychosomatik und Nervenheilkunde (DGPPN) and Deutschen Gesellschaft für Neurologie (DGN). In addition, newer therapeutic approaches and recent publications have been taken into consideration. RESULTS: Before the initiation of treatment, a meaningful differential diagnosis is required to identify potentially reversible causes of dementia syndrome and to determine the correct treatment for specific dementia types. For Alzheimer's disease, acetylcholinesterase inhibitors (donepezil, galantamine, rivastigmin) and memantine are efficacious and provide patient-related benefit. For other dementia types, there is evidence for efficacy of these drugs in some cases. Neuropsychiatric symptoms should first be managed by individual counseling and caregivers education and support. If this is not sufficiently effective, individual psychopharmacological drugs are available for specific conditions. DISCUSSION: Dementia can not be cured, but current treatment can achieve relief of disease burden and improve quality of life for patients and caregivers.

[Potentially inappropriate medication in elderly primary care patients : A retrospective, longitudinal analysis]. / Potenziell inadäquate Medikamente bei älteren hausärztlich versorgten Patientinnen und Patienten : Eine retrospektive Längsschnittanalyse.

BACKGROUND: Elderly people are often burdened by several diseases. This accounts for a higher medication intake and increases the risk of adverse drug events. To minimize this risk, several lists (Beers, PRISCUS) have been published of drugs that elderly patients should not take. We present a longitudinal analysis of the use of potentially inappropriate medication (PIM) over a period 4.5 years in a cohort of patients aged 75 years or more. METHODS: Data were collected from the prospective, multicenter, observational study "German Study on Ageing, Cognition and Dementia in Primary Care Patients (AgeCoDe)," initially enrolling 3,327 patients. We investigated the prevalence of PIM by checking medications during visits to patients' homes. Furthermore, we analyzed the use of individual PIM agents over time. RESULTS: At baseline, we found a PIM prevalence of 29 % according to the PRISCUS list, which decreased to 25.0 % 4.5 years later (χ(2): 7.87, p = 0.004). The Beers list yielded a prevalence of 21 % at baseline, decreasing after 4.5 years to 17.1 % (χ(2): 10.77, p = 0.000). A time-dependent multilevel model confirmed these results. Older age, depression, and the use of numerous prescribed agents are independent risk factors for using a PRISCUS-PIM. CONCLUSION: Our results seem to support a trend toward a more rational drug therapy because fewer patients were prescribed PIM. Thus, for the individual patient, the risk of adverse effects and side effects is reduced as are the costs of these effects.

A genome-wide survey of human short-term memory.

Recent advances in the development of high-throughput genotyping platforms allow for the unbiased identification of genes and genomic sequences related to heritable traits. In this study, we analyzed human short-term memory, which refers to the ability to remember information over a brief period of time and which has been found disturbed in many neuropsychiatric conditions, including schizophrenia and depression. We performed a genome-wide survey at 909 622 polymorphic loci and report six genetic variations significantly associated with human short-term memory performance after genome-wide correction for multiple comparisons. A polymorphism within SCN1A (encoding the α subunit of the type I voltage-gated sodium channel) was replicated in three independent populations of 1699 individuals. Functional magnetic resonance imaging during an n-back working memory task detected SCN1A allele-dependent activation differences in brain regions typically involved in working memory processes. These results suggest an important role for SCN1A in human short-term memory.

[Reliability of morbidity data reported by GPs. Results of a longitudinal study in primary care]. / Reliabilität ärztlicher Morbiditätsangaben zu chronischen Krankheiten. Ergebnisse einer Längsschnittstudie im hausärztlichen Bereich.

BACKGROUND: Data on prevalence of chronic diseases are important for planning health care services. Such prevalence data are mostly based on patient self-reports, claims data, or other research data-with limited validity and reliability partially due to their cross-sectional character. Currently, only claims data of statutory health insurance offer longitudinal information. In Germany, these data show a loss of diagnoses of chronic health conditions over time. This study investigated whether there is a similar tendency of loss in the documentation of chronic diseases in data specifically collected for a longitudinal cohort study by general practitioners. In addition, the explanatory power of patient or GP characteristics regarding these losses is investigated. PATIENTS AND METHODS: A total of 3,327 patients aged 75 years and older were recruited for the German Study on Ageing, Cognition and Dementia in Primary Care Patients (AgeCoDe). For 1,765 patients, GP diagnoses of four chronic conditions at three time points were available for a total period of 4.5 years. In order to explain the loss of chronic diagnoses, a multilevel mixed-effects logistic regression was performed. RESULTS: Over the course of 4.5 years, 18.6% of the diagnoses of diabetes mellitus, 34.5% of the diagnoses of coronary heart disease, and 44.9% of the diagnoses of stroke disappeared in the GP documentation for the longitudinal study. The diagnosis of coronary heart disease was less often lost in men than in women. The risk of losing the diagnosis of diabetes was higher in patients who were well known by the GP for a long time. An essential part of the variance of the losses can be explained by practice (owner) effects. CONCLUSION: Data on morbidity collected in epidemiological studies and reported by physicians should always be checked for validity and reliability. Appropriate options (e.g., an investigator collecting the data directly in the field or the comparison of the data with health insurance companies' claims data) are presented and discussed.