The Nun Study and Alzheimer's disease: Quality of vocation as a potential protective factor?

Regional Brain Volume Changes in Catholic Nuns: A Cross-Sectional Study Using Deep Learning-Based Brain MRI Segmentation

OBJECTIVE

Religious behaviors are considered as complex brain-based phenomena that may be associated with structural brain change. To identify the pattern of regional brain volume change in nuns, we investigated structural alterations in the brains of nuns using a fast processing automated segmentation method based on deep learning algorithms.

METHODS

We retrospectively reviewed the medical records of the catholic sisters between the ages of 31 and 80 who are members of the charity of St. Vincent de Paul of Korea. A total of 193 asymptomatic subjects (86 nuns and 107 control subjects) received comprehensive health screening and underwent brain MRI scans. We compared cortical and sub-cortical volume between groups across multiple locations using our in-house U-Net++ deep learning-based automatic segmentation tool.

RESULTS

Compared to the control group, the nun group displayed increased gray matter volume in the right lingual cortex, left isthmus-cingulate, posterior-cingulate, rostral-middle-frontal, superior-frontal, supramarginal, temporal-pole cortices, and bilateral pars-triangularis cortices after correction for multiple comparisons. On the other hand, the nun group showed reduced gray matter volume in the temporal and parietal regions relative to healthy controls.

CONCLUSION

Our study suggests that spiritual practice may affect brain structure, especially in several frontal regions involved in a higher level of insight function.

Posterior cingulate cortex reveals an expression profile of resilience in cognitively intact elders

The posterior cingulate cortex, a key hub of the default mode network, underlies autobiographical memory retrieval and displays hypometabolic changes early in Alzheimer disease. To obtain an unbiased understanding of the molecular pathobiology of the aged posterior cingulate cortex, we performed RNA sequencing (RNA-seq) on tissue obtained from 26 participants of the Rush Religious Orders Study (11 males/15 females; aged 76-96 years) with a pre-mortem clinical diagnosis of no cognitive impairment and post-mortem neurofibrillary tangle Braak Stages I/II, III, and IV. Transcriptomic data were gathered using next-generation sequencing of RNA extracted from posterior cingulate cortex generating an average of 60 million paired reads per subject. Normalized expression of RNA-seq data was calculated using a global gene annotation and a microRNA profile. Differential expression (DESeq2, edgeR) using Braak staging as the comparison structure isolated genes for dimensional scaling, associative network building and functional clustering. Curated genes were correlated with the Mini-Mental State Examination and semantic, working and episodic memory, visuospatial ability, and a composite Global Cognitive Score. Regulatory mechanisms were determined by co-expression networks with microRNAs and an overlap of transcription factor binding sites. Analysis revealed 750 genes and 12 microRNAs significantly differentially expressed between Braak Stages I/II and III/IV and an associated six groups of transcription factor binding sites. Inputting significantly different gene/network data into a functional annotation clustering model revealed elevated presynaptic, postsynaptic and ATP-related expression in Braak Stages III and IV compared with Stages I/II, suggesting these pathways are integral for cognitive resilience seen in unimpaired elderly subjects. Principal component analysis and Kruskal-Wallis testing did not associate Braak stage with cognitive function. However, Spearman correlations between genes and cognitive test scores followed by network analysis revealed upregulation of classes of synaptic genes positively associated with performance on the visuospatial perceptual orientation domain. Upregulation of key synaptic genes suggests a role for these transcripts and associated synaptic pathways in cognitive resilience seen in elders despite Alzheimer disease pathology and dementia.

Czech and Slovak Members of Religious Institutes: Their Health in Comparison to the General Population

This study examines the general health of consecrated persons (CP) in the Czech Republic (CZ) and in Slovakia (SK) compared to control samples of the Czech population. The sample of 293 CP participants (age: M = 47.52, SD = 9.57, females: 78.88%, 180 Czechs, 213 Slovaks) was compared with two control samples, one of which was nationally representative. Comparing CP with the general population, we measured the frequency of recent health complaints, the occurrence of chronic illnesses, general health and the individual chronotype. Compared to the representative sample, CP had a higher chance of suffering from pelvis minor pain and obesity but a lower chance of diabetes. Furthermore, CP had higher odds of having worse general health. Comparing “larks” with “night owls” among CP, the “night owls” had a significantly higher chance of suffering from worse general health. “Night owl” CP also seem to suffer more from backache and depression/anxiety and to have more problems with falling asleep. Compared to the overall society, CP in CZ and SK tend to have similar or worse general health. The results differ from the findings in the US, pointing to the positive health effects of the spiritual experience and structured daily routine of CP. Thus, this study shows the importance of more detailed research on the way of life of Czech and Slovak CP to determine the factors with the most negative health effects.

Study of the Risk and Preventive Factors for Progress of Mild Cognitive Impairment to Dementia

OBJECTIVE

To evaluate the risk factors for progress of mild cognitive impairment to dementia.

METHODS

This study was based on the epidemiological survey in 2011 (No. PKJ2010-Y26) and contained 441 MCI individuals. Cognitive function was measured by the Mini-Mental Status Examination, clinical dementia rating, and montreal cognitive assessment. The association between demographic characteristics and MCI outcomes were evaluated using single-and multifactor ordered logistic regression analysis models.

RESULTS

Of the 441 MCI, 77 progressed to dementia (MCIp: 17.5%, 95% CI: 14.4%-21.6%), 356 remained stable (MCIs: 80.7%, 95% CI: 77.0%-88.4%), and 8 reverted to normal cognition (MCIr: 1.8%, 95% CI: 0.6%-3.0%) at follow-up in 2017. Univariate ordinal regression analysis showed that diabetes (P = .052), marriage (P = .028), worker (P = .069), and manager (P = .075) may be the risk factor for the status of MCI. Multiple ordinal regression results showed that diabetes (P = .049) and marriage (P = .04) significantly affected the cognitive function changes in the MCI patients.

CONCLUSION

Nondiabetics and being married may prevent the progression from MCI to dementia.