The Association Between Generalized Anxiety Disorder and Resting-State Prefrontal Cortex Oxygenation Is Modified by Self-Reported Physical Activity: Results From The Irish Longitudinal Study on Ageing

Physical activity dose for generalized anxiety disorder & worry: Results from the Irish longitudinal study on ageing

The lowest moderate-to-vigorous physical activity (MVPA) dose that conveys protection for Generalized Anxiety Disorder (GAD) and worry is unknown. This study quantified associations of weekly accumulated MVPA doses with GAD and worry across 10 years using data from The Irish Longitudinal Study on Ageing (TILDA). Continuous MVPA (metabolic equivalent of task [MET] minutes per week [MET.min.week-1]; e.g., moderate-intensity brisk walking = 4METs), three-dose and, more precise, five-dose MVPA categories were examined. Worry symptoms and GAD status were measured using the Penn State Worry Questionnaire-Abbreviated and the Composite International Diagnostic Interview. Multivariable negative random effect binomial regression and logistic models adjusted for relevant covariates quantified associations across time. Among the 7,650 participants, compared to no MVPA (0 MET.min.week-1), 18 % (OR: 0.82; 95 %CI: [0.69-0.98]), 22 % (OR: 0.78; [ 0.64-0.95]) and 31 % (OR: 0.69; [0.59-0.79]) lower odds of GAD were found for the doses of 1-<600, 600-<1,200 and ≥2,400 MET.min.week-1 respectively. Post-hoc analysis demonstrated 47 % lower odds (OR: 0.53; (0.36-0.78) of GAD for 1-<200 MET.min.week1 compared to inactivity. Compared to no activity, engaging in even minimal physical activity equivalent of 10 min/day for five days/week of moderate-intensity activity (e.g., brisk walking), may lower the risk of GAD over time among older adults.

Capturing postural blood pressure dynamics with near-infrared spectroscopy-measured cerebral oxygenation

Orthostatic hypotension (OH) is highly prevalent in older adults and associated with dizziness, falls, lower physical and cognitive function, cardiovascular disease, and mortality. OH is currently diagnosed in a clinical setting with single-time point cuff measurements. Continuous blood pressure (BP) devices can measure OH dynamics but cannot be used for daily life monitoring. Near-infrared spectroscopy (NIRS) has potential diagnostic value in measuring cerebral oxygenation continuously over a longer time period, but this needs further validation. This study aimed to compare NIRS-measured (cerebral) oxygenation with continuous BP and transcranial Doppler-measured cerebral blood velocity (CBv) during postural changes. This cross-sectional study included 41 participants between 20 and 88 years old. BP, CBv, and cerebral (long channels) and superficial (short channels) oxygenated hemoglobin (O2Hb) were measured continuously during various postural changes. Pearson correlations between BP, CBv, and O2Hb were calculated over curves and specific characteristics (maximum drop amplitude and recovery). BP and O2Hb only showed good curve-based correlations (0.58-0.75) in the initial 30 s after standing up. Early (30-40 s) and 1-min BP recovery associated significantly with O2Hb, but no consistent associations were found for maximum drop amplitude and late (60-175 s) recovery values. Associations between CBv and O2Hb were poor, but stronger for long-channel than short-channel measurements. BP associated well with NIRS-measured O2Hb in the first 30 s after postural change. Stronger associations for CBv with long-channel O2Hb suggest that long-channel NIRS specifically reflects cerebral blood flow during postural transitions, necessary to better understand the consequences of OH such as intolerance symptoms.

Age and sex related differences in orthostatic cerebral oxygenation: Findings from 2764 older adults in the Irish Longitudinal Study on Ageing (TILDA)

AIMS

Cerebral hypoperfusion is implicated in the pathogenesis of associations between orthostatic hypotension and adverse outcome such as falls, cognitive impairment, depression, and mortality. Although the blood pressure response to orthostasis has been well studied there is a lack of information on orthostatic cerebrovascular responses in older populations.

METHODS AND RESULTS

We measured cerebral hemodynamics, utilizing near infrared spectroscopy, coupled with peripheral blood pressure during an active stand in a large population of well-phenotyped older adults (N = 2764). Multi-level mixed effect models were utilized to investigate associations with age and sex, as well as confounders including anti-hypertensive medications. Normative cerebral oxygenation responses were also modelled utilizing generalized additive models for location, scale, and shape (GAMLSS). Older age groups experienced larger initial drops in oxygenation and a slower recovery, and responses also differed by sex. The drop after standing ranged from -1.85 % (CI: -2.02 to -1.68) in the males aged 54-59 years vs -1.15 % (CI: -1.31 to -1.00 %) in females aged 54-59 years, to -2.67 % (CI: -3.01 to -2.33) in males aged ≥ 80 years vs -1.97 % (CI: -2.32 to -1.62) females aged ≥ 80 years. Reduced oxygenation levels were also evident in those taking anti-hypertensive medications.

CONCLUSION

Cerebral autoregulation is impaired with age, particularly in older women and those taking anti-hypertensives. SBP during the stand explained some of the age gradient in the late recovery stage of the stand for the oldest age group. Reported orthostatic symptoms did not correlate with hypoperfusion. Therefore, measures of orthostatic cerebral flow should be assessed in addition to peripheral BP in older patients irrespective of symptoms. Further studies are required to investigate the relationship between NIRS measurements and clinical outcomes such as falls, cognitive impairment and depression.

Executive Functioning Constructs in Anxiety, Obsessive-Compulsive, Post-Traumatic Stress, and Related Disorders

PURPOSE OF REVIEW

We synthesize theories proposing complex relations between cognitive functioning and anxiety-related concepts. We evaluate vulnerability theories suggesting that deficits in various cognitive functioning domains predict future anxiety-associated concepts. We examine scar theories asserting the opposite direction of effects (i.e., anxiety predicting cognitive dysfunction). Furthermore, we examine more novel frameworks on this topic.

RECENT FINDINGS

Reliable evidence exists for the scar and vulnerability theories. This includes mounting data on diverse anxiety symptoms predicting cognitive dysfunction (and conversely) unfolding at between- and within-person levels (dynamic mutualism theory). It also includes data on the stronger effects or central influence of anxiety (versus non-anxiety) symptoms on executive functioning (EF; i.e., higher-order cognitive control governing myriad thinking and action repertoires) versus non-EF domains and vice versa (network theory). In addition, it reviews emerging evidence that enhanced cognitive control can correlate with higher anxiety among children (overgeneralized control theory). The generally inverse relations between anxiety symptoms and cognitive dysfunction are bidirectional and complex within and between persons. Plausible mediators and moderators merit more attention, including immune, metabolism, and neural markers and the social determinants of health.