Alleles associated with physical activity levels are estimated to be older than anatomically modern humans

Cross-sectional and longitudinal interaction effects of physical activity and APOE-ε4 on white matter integrity in older adults: The MAPT study

BACKGROUND

Physical activity (PA) has been shown to modulate the detrimental effect of carrying the apolipoprotein-E epsilon 4 (APOE-ɛ4) allele on brain structure. However, the current literature mainly provides cross-sectional data, and longitudinal studies investigating the interaction between genotype and PA on white matter (WM) integrity are lacking.

OBJECTIVES

We investigated both the cross-sectional and the longitudinal interactive effects of APOE-ɛ4 and PA on WM integrity in older adults.

METHODS

Fractional anisotropy, as well as axial, radial, and mean diffusivity, extracted from brain diffusion tensor imaging (DTI) were used to assess WM integrity in non-demented older adults. They were categorized according to their APOE-ɛ4 status (carriers vs. non-carriers), and their level of total (TPA), moderate to vigorous (MVPA) and light (LPA) PA were assessed using a questionnaire. Mixed model regressions were performed to test the interactive effects of APOE-ɛ4 status and PA on WM integrity at baseline and over a 3-year follow-up.

RESULTS

190 subjects with a mean age 74.5 years (SD = 3.9) were examined. Despite a lack of cross-sectional associations, sensitivity analyses revealed that, in the carrier group only, higher levels of LPA, but not MVPA, were mainly associated with higher axial and mean diffusivity values over time.

CONCLUSIONS

This study partially confirms the previously reported interactive associations between PA, APOE-ɛ4 genotype and WM integrity, supporting the hypothesis that PA may protect against fiber loss in WM tracts containing crossing fibers. Future studies assessing sedentary behaviors in addition to PA could bring relevant contributions to the field. CLINICAL TRIAL REGISTRATION NUMBER FROM CLINICALTRIALS.GOV: NCT00672685.

The spatiotemporal movement of patients in and out of a psychiatric hospital: an observational GPS study

BACKGROUND

Movement is a basic component of health. Little is known about the spatiotemporal movement of patients with mental disorders. The aim of this study was to determine how spatiotemporal movement of patients related to their symptoms and wellbeing.

METHOD

A total of 106 patients (inpatients (n = 69) and outpatients (n = 37)) treated for a wide range of mental disorders (transdiagnostic sample) carried a GPS-enabled smartphone for one week at the beginning of treatment. Algorithms were applied to establish spatiotemporal clusters and subsequently related to known characteristics of these groups (i.e., at the hospital, at home). Symptomatology, Wellbeing, and Psychological flexibility were also assessed.

RESULTS

Spatiotemporal patterns of inpatients and outpatients showed differences consistent with predictions (e.g., outpatients showed higher active areas). These patterns were largely unassociated with symptoms (except for agoraphobic symptoms). Greater movement and variety of movement were more predictive of wellbeing, however, in both inpatients and outpatients.

CONCLUSION

Measuring spatiotemporal patterns is feasible, predictive of wellbeing, and may be a marker of patient functioning. Ethical issues of collecting GPS data are discussed.