Martha Dlugaj

Effect of long-term outdoor air pollution and noise on cognitive and psychological functions in adults.

It has been hypothesized that air pollution and ambient noise might impact neurocognitive function. Early studies mostly investigated the associations of air pollution and ambient noise exposure with cognitive development in children. More recently, several studies investigating associations with neurocognitive function, mood disorders, and neurodegenerative disease in adult populations were published, yielding inconsistent results. The purpose of this review is to summarize the current evidence on air pollution and noise effects on mental health in adults. We included studies in adult populations (≥18 years old) published in English language in peer-reviewed journals. Fifteen articles related to long-term effects of air pollution and eight articles on long-term effects of ambient noise were extracted. Both exposures were separately shown to be associated with one or several measures of global cognitive function, verbal and nonverbal learning and memory, activities of daily living, depressive symptoms, elevated anxiety, and nuisance. No study considered both exposures simultaneously and few studies investigated progression of neurocognitive decline or psychological factors. The existing evidence generally supports associations of environmental factors with mental health, but does not suffice for an overall conclusion about the independent effect of air pollution and noise. There is a need for studies investigating simultaneously air pollution and noise exposures in association mental health, for longitudinal studies to corroborate findings from cross-sectional analyses, and for parallel toxicological and epidemiological studies to elucidate mechanisms and pathways of action.

Long-term air pollution and traffic noise exposures and mild cognitive impairment in older adults : a cross-sectional analysis of the Heinz Nixdorf recall study

Background: Mild cognitive impairment (MCI) describes the intermediate state between normal cognitive aging and dementia. Adverse effects of air pollution (AP) on cognitive functions have been proposed, but investigations of simultaneous exposure to noise are scarce. Objectives: We analyzed the cross-sectional associations of long-term exposure to AP and traffic noise with overall MCI and amnestic (aMCI) and nonamnestic (naMCI) MCI. Methods: At the second examination of the population-based Heinz Nixdorf Recall study, cognitive assessment was completed in 4,086 participants who were 50–80 years old. Of these, 592 participants were diagnosed as having MCI (aMCI, n = 309; naMCI, n = 283) according to previously published criteria using five neuropsychological subtests. We assessed long-term residential concentrations for size-fractioned particulate matter (PM) and nitrogen oxides with land use regression, and for traffic noise [weighted 24-hr (LDEN) and night-time (LNIGHT) means]. Logistic regression models adjusted for individual risk factors were calculated to estimate the association of environmental exposures with MCI in single- and two-exposure models. Results: Most air pollutants and traffic noise were associated with overall MCI and aMCI. For example, an interquartile range increase in PM2.5 and a 10 A-weighted decibel [dB(A)] increase in LDEN were associated with overall MCI as follows [odds ratio (95% confidence interval)]: 1.16 (1.05, 1.27) and 1.40 (1.03, 1.91), respectively, and with aMCI as follows: 1.22 (1.08, 1.38) and 1.53 (1.05, 2.24), respectively. In two-exposure models, AP and noise associations were attenuated [e.g., for aMCI, PM2.5 1.13 (0.98, 1.30) and LDEN 1.46 (1.11, 1.92)]. Conclusions: Long-term exposures to air pollution and traffic noise were positively associated with MCI, mainly with the amnestic subtype. Citation: Tzivian L, Dlugaj M, Winkler A, Weinmayr G, Hennig F, Fuks KB, Vossoughi M, Schikowski T, Weimar C, Erbel R, Jöckel KH, Moebus S, Hoffmann B, on behalf of the Heinz Nixdorf Recall study Investigative Group. 2016. Long-term air pollution and traffic noise exposures and mild cognitive impairment in older adults: a cross-sectional analysis of the Heinz Nixdorf Recall Study. Environ Health Perspect 124:1361–1368; http://dx.doi.org/10.1289/ehp.1509824

Automatic segmentation of cerebral white matter hyperintensities using only 3D FLAIR images.

Magnetic Resonance (MR) white matter hyperintensities have been shown to predict an increased risk of developing cognitive decline. However, their actual role in the conversion to dementia is still not fully understood. Automatic segmentation methods can help in the screening and monitoring of Mild Cognitive Impairment patients who take part in large population-based studies. Most existing segmentation approaches use multimodal MR images. However, multiple acquisitions represent a limitation in terms of both patient comfort and computational complexity of the algorithms. In this work, we propose an automatic lesion segmentation method that uses only three-dimensional fluid-attenuation inversion recovery (FLAIR) images. We use a modified context-sensitive Gaussian mixture model to determine voxel class probabilities, followed by correction of FLAIR artifacts. We evaluate the method against the manual segmentation performed by an experienced neuroradiologist and compare the results with other unimodal segmentation approaches. Finally, we apply our method to the segmentation of multiple sclerosis lesions by using a publicly available benchmark dataset. Results show a similar performance to other state-of-the-art multimodal methods, as well as to the human rater.

Prevalence of Mild Cognitive Impairment and Its Subtypes in the Heinz Nixdorf Recall Study Cohort

Aims: We investigated the prevalence of mild cognitive impairment (MCI) and its subtypes according to the original (MCI-original) and modified (MCI-modified; neglecting cognitive complaints) Petersen criteria. Methods: 4,145 subjects (aged 50–80 years) from a German population-based study completed a cognitive screening test and were poststratified into 2 groups with sample sizes of 1,125 for impaired and 3,020 for age-appropriate performance. Random samples of 445 impaired participants and 211 age-appropriate participants received a detailed neuropsychological evaluation. The prevalence of MCI was estimated by a bias correction estimator based on stratum weights. The association between MCI and age, gender and education was analyzed in a logistic regression model. Results: The estimated MCI prevalence was 7.8% (95% CI: 5.7–9.9%) for the original, and 12.1% (95% CI: 9.8–14.4%) for the modified criteria. In the MCI-original group, amnestic MCI subtypes were slightly less common than non-amnestic MCI subtypes (3.5 vs. 4.3%). MCI-original was associated with lower education and older age. In the MCI-modified group, the amnestic subtypes were more common than the non-amnestic MCI subtypes (7.8 vs. 4.3%), and MCI was associated with age, gender and education. Conclusions: Prevalence rates of MCI are high in the general population and vary considerably according to the criteria applied.

Association of diabetes mellitus and mild cognitive impairment in middle-aged men and women.

BACKGROUND Several studies reported on the association of type 2 diabetes (T2DM) with dementia. Studies on the association of T2DM and mild cognitive impairment (MCI) are rare. OBJECTIVE To evaluate the gender-specific association of T2DM with MCI and MCI subtypes (amnestic MCI (aMCI) and non-amnestic MCI (naMCI)) in a middle-aged (50-65 years) and old-aged (66-80 years) population-based study sample. METHODS We compared 560 participants with MCI (aMCI n = 289, naMCI n = 271) with 1,376 cognitively normal participants from the Heinz Nixdorf Recall study. Diabetic status was based on self-reported physicians diagnosis or treatment with anti-diabetic medication. We performed group comparisons regarding all cognitive subtests for participants with and without T2DM. Logistic regression models (adjusted for age, education, cardiovascular risk factors, and depression) were used to determine the association of T2DM with MCI and MCI subtypes. RESULTS In the middle-aged group, fully adjusted models showed an association (odds ratio, 95% CI) of T2DM with MCI that was more pronounced in men (total: 2.03, 1.23-3.36, men: 2.16, 1.12-4.14, women 1.69, 0.73-3.89). T2DM was associated with MCI subtypes (aMCI: 2.01, 1.08-3.73; naMCI: 2.06, 1.06-3.98), whereas, the association was stronger with naMCI in men (2.61, 1.14-5.98) and with aMCI in women (3.02, 1.27-7.17). We found no total or gender-specific association of T2DM with MCI or MCI subtypes in the old-aged group. CONCLUSIONS Our data show that T2DM is associated with MCI and MCI subtypes in middle-aged, but not in old-aged participants. Furthermore, the results indicate a gender-specific vulnerability of T2DM on cognition, especially in MCI subtypes.

Sleep-Disordered Breathing, Sleep Quality, and Mild Cognitive Impairment in the General Population

There is increasing evidence that sleep disorders are associated with cognitive decline. We, therefore, examined the cross-sectional association of sleep-disordered breathing (SDB), sleep quality, and three types of sleep complaints (difficulties initiating sleep, difficulties maintaining sleep, and early morning awakening) with mild cognitive impairment (MCI) and its subtypes. A group of 1,793 participants (51% men; 63.8 ± 7.5 years) of the population-based Heinz Nixdorf Recall study (total sample n = 4,157) received a screening for SDB and self-report measures of sleep complaints. Group comparisons were used to compare performances among five cognitive subtests. Multivariate logistic regression models were calculated to determine the association of MCI (n = 230) and MCI subtypes (amnestic MCI, n = 120; non-amnestic MCI, n = 110) with SDB severity levels, poor sleep quality, and sleep complaints. Severe SDB (apnea-hypopnea index ≥30/h, n = 143) was not associated with MCI, amnestic MCI, or non-amnestic MCI. Poor sleep quality was associated with MCI (Odds ratio (OR) = 1.40, 95% confidence interval (CI) = 1.02-2.03; fully adjusted) as well as frequently reported difficulties initiating sleep (OR = 1.94, 1.20-3.14), difficulties maintaining sleep (OR = 2.23, 1.27-4.63), and early morning awakening (OR = 2.30, 1.32-4.00). Severe difficulties initiating sleep (OR = 2.23, 1.21-4.13) and early morning awakening (OR = 2.88, 1.45-5.73) were solely associated with the amnestic MCI subtype, whereas, severe difficulties maintaining sleep (OR = 3.84, 1.13-13.08) were associated with non-amnestic MCI. Our results suggest that poor sleep quality, rather than SDB, is associated with MCI. The selective association of difficulties initiating sleep and early morning awakening with amnestic MCI and of difficulties maintaining sleep with non-amnestic MCI might serve as a marker to improve diagnostic accuracy in the earliest stages of cognitive impairment and will be further investigated in our longitudinal examination.

Elevated Levels of High-Sensitivity C-Reactive Protein are Associated with Mild Cognitive Impairment and its Subtypes: Results of a Population-Based Case-Control Study

As high-sensitivity C-reactive protein (hsCRP) seems to be associated with an increased risk of cognitive decline, this nested case-control study examined the relation of hsCRP and mild cognitive impairment (MCI) at different time points. 148 MCI cases (106 amnestic, 42 non-amnestic (aMCI/naMCI)) and 148 matched controls were identified from a prospective population based cohort study of 4,359 participants (aged 50-80). HsCRP levels were measured 5 years before (baseline) and at the time of neuropsychological testing (follow-up). Odds ratios (OR) for hsCRP quartiles serum levels were calculated for the two time points using logistic regression analyses and were adjusted for cardiovascular covariates. In the fully adjusted model, baseline hsCRP levels were significantly associated with both MCI and aMCI (OR = 2.29, 95% confidence interval (CI), 1.01-5.15, first versus fourth quartile, respective OR = 2.73, 95% CI, 1.09-6.84). At follow-up, the fourth hsCRP quartile was associated with MCI (OR = 3.60, 95% CI, 1.55-8.33), aMCI (OR = 3.73, 95% CI, 1.52-9.17) and naMCI (OR = 3.66, 95% CI, 1.00-13.77). Elevated hsCRP levels, even detected five years before diagnosis, are associated with an at least twofold increased probability of MCI. These findings suggest that inflammation plays an important role in the development and presence of cognitive impairment.

Population-based distribution and psychometric properties of a short cognitive performance measure in the population-based Heinz Nixdorf Recall Study.

Background: Providing a valid and sensitive measure of different domains of cognitive performance in epidemiologic studies of early old-age populations presents a methodological challenge, given the broad range of variability in cognitive functioning in this age group. Objectives: (1) To provide data on the distribution of cognitive performance scores in a representative sample of an early old-age population, and (2) to assess psychometric properties of a short cognitive performance measure developed within the framework of a cohort study. Design: Population-based cohort study. Setting and Participants: As part of the second examination of the Heinz Nixdorf Recall Study, 4,145 participants aged 50–80 years underwent a short cognitive performance assessment composed of 5 subtests with a mean duration of 7.31 min. Additionally, a subsample of 656 participants had a detailed neuropsychological and neurological examination. Methods: Age- and education-specific cognitive performance scores in the total sample were calculated. Based on data from the subsample, concurrent validity was examined by comparing findings with a clinically validated neuropsychological assessment. Results: In the total sample, younger and more highly educated participants had higher scores of cognitive performance. In the subsample, a good accuracy [area under the curve (AUC) = 0.81 (0.74–0.87)] of the short cognitive performance assessment compared with results from a clinically established Alzheimer disease assessment scale and diagnosis of mild cognitive impairment [AUC = 0.82 (0.78–0.82)] was observed. Conclusion: This brief, cognitive performance measure, documenting good psychometric properties, can be useful in future epidemiological investigations exploring different domains and overall cognitive functioning in early old-age populations.

Long-term air pollution and traffic noise exposures and cognitive function:A cross-sectional analysis of the Heinz Nixdorf Recall study

ABSTRACT Investigations of adverse effects of air pollution (AP) and ambient noise on cognitive functions are apparently scarce, and findings seem to be inconsistent. The aim of this study was to examine the associations of long-term exposure to AP and traffic noise with cognitive performance. At the second examination of the population-based Heinz Nixdorf Recall study (2006–2008), cognitive performance was evaluated in 4086 participants. Long-term residential exposure to size-specific particulate matter (PM) and nitrogen oxides (NOx) with land use regression, to and traffic noise (weighted 24-h (LDEN) and nighttime (LNIGHT) means), was assessed according to the European Union (EU) Directive 2002/49/EC. Multiple regression models were calculated for the relationship of environmental exposures with a global cognitive score (GCS) and in five cognitive subtests, using single- and two-exposure models. In fully adjusted models, several AP metrics were negatively associated with four of five subtests and with GCS. For example, an interquartile range increase in PM2.5 was correlated with verbal fluency, labyrinth test, and immediate and delayed verbal recall. A 10 dB(A) elevation in LDEN and LNIGHT was associated with GCS. Similar but not significant associations were found for the cognitive subtests. In two-exposure models including noise and air pollution simultaneously, the associations did not change markedly for air pollution, but attenuated numerically for noise. Long-term exposures to AP and traffic noise are negatively correlated with subtests related to memory and executive functions. There appears to be little evidence for mutual confounding.

Thyroid-Stimulating Hormone and Mild Cognitive Impairment: Results of the Heinz Nixdorf Recall Study

BACKGROUND Although some studies reported on the association of serum thyroid-stimulating hormone (TSH) concentration and cognition, only one population-based study investigated the association of TSH concentration and mild cognitive impairment (MCI). OBJECTIVE To investigate the gender-specific association of low- and high-normal TSH concentrations with MCI in euthyroid participants. METHODS Analysis sample 1 included 2,563 euthyroid participants (aged 50-80 years) from the second examination of the population-based Heinz Nixdorf Recall study. Gender-specific TSH quintiles (Q1 low, Q2-Q4 middle, Q5 high TSH concentration) were determined and group comparisons of age- and education-adjusted mean scores were performed for all cognitive subtests. Analysis sample 2 included 378 participants with MCI and 931 cognitively normal participants. MCI was diagnosed according to previously published MCI criteria. Multivariate logistic regression models were performed using TSH quintiles (Q2-Q4 as reference) to assess the association of low- and high-normal TSH concentration with MCI. Models were performed unadjusted and adjusted for sociodemographic and cardiovascular risk factors. RESULTS Group comparisons showed significant differences only in the immediate recall of the verbal memory task in women. Only women showed a strong association of high-normal TSH concentration with MCI (unadjusted: odds ratio 2.09, 95% confidence interval 1.29-3.37, full adjusted: 1.86, 1.06-3.27). There was no association with low-normal TSH concentration in women and no association of either low- or high-normal TSH concentration with MCI in men. CONCLUSIONS These results suggest that women with high-normal TSH concentration might be at higher risk of cognitive decline. This needs to be confirmed in the longitudinal analysis.