Cerebral haemodynamics and depression in the elderly

Forgetful, sad and old: Do vascular cognitive impairment and depression share a common pre-disease network and how is it impacted by ageing?

Vascular cognitive impairment (VCI) and depression frequently coexist in geriatric populations and reciprocally increase disease risks. We assert that a shared pre-disease state of the psycho-immune-neuroendocrine (PINE) network model mechanistically explains bidirectional associations between VCI and depression. Five pathophysiological sub-networks are identified that are shared by VCI and depression: neuroinflammation, kynurenine pathway imbalance, hypothalamic-pituitary-adrenal (HPA) axis overactivity, impaired neurotrophic support and cerebrovascular dysfunction. These do not act independently, and their complex interactions necessitate a systems biology approach to better define disease pathogenesis. The PINE network is already established in the context of non-communicable diseases (NCDs) such as depression, hypertension, atherosclerosis, coronary heart disease and type 2 diabetes mellitus. We build on previous literature to specifically explore mechanistic links between MDD and VCI in the context of PINE pathways and discuss key mechanistic commonalities linking these comorbid conditions and identify a common pre-disease state which precedes transition to VCI and MDD. We expand the model to incorporate bidirectional interactions with biological ageing. Diathesis factors for both VCI and depression feed into this network and the culmination of shared mechanisms (on an ageing substrate) lead to a critical network transition to one or both disease states. A common pre-disease state underlying VCI and depression can provide clinicians a unique opportunity for early risk assessment and intervention in disease development. Establishing the mechanistic elements and systems biology of this network can reveal early warning or predictive biomarkers together with novel therapeutic targets. Integrative studies are recommended to elucidate the dynamic networked biology of VCI and depression over time.

Analysis of cervical and upper thoracic spinal segmental rotation angles during end-range neck rotation: Comparison with and without neck pain

BACKGROUND

Neck pain is a common manifestation of musculoskeletal disorders of the cervical and thoracic spine. Manual therapy interventions to the thoracic spine are recommended for treating patients with several types of neck pain. However, only a few studies have investigated the thoracic spine mobility associated with neck movement.

OBJECTIVES

Compare cervical and upper thoracic rotation angles in subjects with and without neck pain.

METHODS

The subjects included nine individuals who experienced neck pain (pain, Group P) and 11 who did not (non-pain, Group N). The rotation angle was measured using MRI. The imaging limb position was at 90% of the maximum neck rotation. The MR images were analyzed using image analysis software to calculate the rotation angle of C1 to Th3. The rotation angle of the segment was then calculated by subtracting the rotation angle corresponding to the lower vertebra from that corresponding to the upper vertebra. The total rotation of each segment was calculated as the sum of the right and left rotation angle. Then, the segmental rotation angles were compared between groups.

RESULTS/FINDINGS

The rotation angles of C3-C4, C7-Th1, and Th1-Th2 were significantly smaller in Group P than in Group N, and C5-C6 and C6-C7 were significantly larger in Group P than in Group N. There was no statistical difference in rotational angle at all other spinal levels measured.

CONCLUSIONS

The results of this study indicate subjects with neck pain had hypermobility of the lower cervical spine and hypomobility of the cervico-thoracic junction and upper thoracic spine compared with subjects without neck pain. These results add to current understanding of biomechanical factors that may be related to neck pain.

Alteration in cerebral blood flow, kynurenines with respect to mood profile in freshly recruited armed forces personnel

The present study is conducted to understand the association of mood profile with the kynurenine pathway (KP) metabolites, and cerebral hemodynamics in freshly recruited central armed forces personnel. Profile of Mood States questionnaire was utilized to assess mood profile, and Total Mood Disturbance (TMD) score was calculated. Transcranial Doppler was used to record blood flow velocity bilaterally of the middle cerebral artery. Chromatographic profile of the kynurenine metabolites was obtained in serum. Further, personnel were stratified according to sociodemographic variables (gender, age and diet) to observe the changes in their KP metabolic status. An activation of the kynurenic acid branch of the KP and the reduction in the mean blood flow velocity, and an increase in Gosling pulsatility index (PI) were observed in females having high TMD score. On gender comparative analysis, kynurenine metabolites of quinolinic acid branch and serotonin were significantly high in males. In males, with increase in age, a significant increase in the quinolinic acid branch of the KP was observed. Furthermore, a significant difference in level metabolites of the KP among the vegetarian and non-vegetarian groups was also observed. In conclusion we observed that increased TMD score was associated with cerebral hypoperfusion and higher vascular resistance along with activation of the KP. Our findings highlighted the importance of multi-facet brain function to showcase the close interaction of various dimensionalities and true picture of the assessee.

Investigating the association between depression and cerebral haemodynamics-A systematic review and meta-analysis

BACKGROUND

Vascular mechanisms may play a role in depression. The aim of this review is to summarise the evidence on alterations in cerebral haemodynamics in depression.

METHODS

MEDLINE (1946- present), Embase (1947-present), Web of Science (1970-present), PsycINFO (1984-present), CINAHL (1976-present) and CENTRAL were searched using a predefined search strategy. A meta-analysis was conducted in four groups: 1) global cerebral blood flow (CBF) in ml/min/100 g, 2) CBF velocity (CBFv) in cm/s (maximum flow of left middle cerebral artery, 3) combined CBF and CBFv, 4) Ratio of uptake of Tc 99 m HMPAO (region of interest compared to whole brain). Data are presented as mean difference or standardised mean difference and 95% confidence interval (95% CI). A narrative synthesis of the remaining studies was performed.

RESULTS

87 studies were included. CBF was significantly reduced in depressed patients compared to HC [15 studies, 538 patients, 416 HC, MD: -2.24 (95% CI -4.12, -0.36), p = 0.02, I² = 64%]. There were no statistically significant differences in other parameters. The narrative synthesis revealed variable changes in CBF in depressed patients, particularly affecting the anterior cingulate and prefrontal cortices.

LIMITATIONS

There were various sources of heterogeneity including the severity of depression, use of antidepressant medication, imaging modality used and reporting of outcomes. All of these factors made direct comparisons between studies difficult.

CONCLUSIONS

The reduction in CBF in depressed patients compared to HCs may indicate a role for assessment and CBF altering interventions in high-risk groups. However, results were inconsistent across studies, warranting further work to investigate specific subgroups.

Cerebrovascular reactivity is blunted in young adults with major depressive disorder: The influence of current depressive symptomology

BACKGROUND

In middle-aged adults with depression, cerebral vasodilatory reactivity is blunted; however, this has not been examined in treatment-naïve young adults with major depressive disorder (MDD). We tested the hypothesis that cerebrovascular reactivity would be blunted in young adults (18-30 yrs) with MDD compared to healthy non-depressed adults (HA) and would be attenuated to a greater extent in adults with symptomatic MDD (sMDD) compared to adults with MDD in remission (euthymic MDD; eMDD).

METHODS

Sixteen adults with MDD [21±3yrs; n = 8 sMDD (6 women); n = 8 eMDD (5 women)] and 14 HA (22±3yrs; 9 women) participated. End-tidal carbon dioxide concentration (P_ETCO₂; capnograph), beat-to-beat mean arterial pressure (MAP; finger photoplethysmography), middle cerebral artery blood velocity (MCAv; transcranial Doppler ultrasound), and internal carotid artery (ICA) diameter and blood velocity (Doppler ultrasound) were continuously measured during baseline and rebreathing-induced hypercapnia. Cerebrovascular reactivity was calculated as the relative increase in vascular conductance during hypercapnia.

RESULTS

In adults with MDD, cerebrovascular reactivity in the MCA (∆39±9 HA vs. ∆31±13% MDD, p = 0.04), but not the ICA (∆36±24 HA vs. ∆34±18% MDD, p = 0.84), was blunted compared to HA. In the MCA, cerebrovascular reactivity was reduced in adults with sMDD compared to adults with eMDD (∆36±11 eMDD vs. ∆25±13% sMDD, p = 0.02).

LIMITATIONS

The cross-sectional nature approach limits conclusions regarding the temporal nature of this link.

CONCLUSION

These data indicate that MCA cerebrovascular reactivity is blunted in young adults with MDD and further modulated by current depressive symptomology, suggesting that the management of depressive symptomology may secondarily improve cerebrovascular health.

Higher fasting C-peptide is associated with post-stroke depression: a multicenter prospective cohort study

BACKGROUND

Fasting C-peptide (FCP) has been shown to play an important role in the pathophysiology of mood disorders including depression and schizophrenia, but it is unknown whether it also predicts post-stroke depression (PSD). This study examined the association between FCP and PSD at 6 months after acute ischemic-stroke onset among Chinese subjects.

METHODS

A total of 656 stroke patients were consecutively recruited from three hospitals of Wuhan city, Hubei province. Clinical and laboratory data were collected on admission. PSD status was evaluated by DSM-V criteria and 17-item Hamilton Rating Scale for Depression (HAMD-17) at 6 months after acute ischemic stroke. The χ2-test, Mann-Whitney U-test, and t-test were used to check for statistical significance. Multivariate logistic regression model was used to explore independent predictor of PSD.

RESULTS

In the univariate analysis, significant differences were found between the PSD and non-PSD groups in terms of FCP level (p = 0.009). After multivariate adjustments, FCP remained a significant independent predictor of PSD, with an adjusted odds ratio of 1.179 (95%CI: 1.040-1.337, p = 0.010).

CONCLUSIONS

Higher FCP levels on admission were found to be associated with PSD at 6 months after acute ischemic-stroke onset. For stroke patients, doctors should pay attention to the baseline FCP for screening high-risk PSD in clinical practice.

Microvascular Contribution to Late-Onset Depression: Mechanisms, Current Evidence, Association With Other Brain Diseases, and Therapeutic Perspectives

Depression is common in older individuals and is associated with high disability and mortality. A major problem is treatment resistance: >50% of older patients do not respond to current antidepressants. Therefore, new effective interventions for prevention and treatment of depression in older individuals need to be developed, which requires a better understanding of the mechanisms underlying depression. The pathophysiology of depression is multifactorial and complex. Microvascular dysfunction may be an early and targetable mechanism in the development of depression, notably depression that initiates in late life (late-onset depression). Late-onset depression commonly co-occurs with other diseases or syndromes that may share a microvascular origin, including apathy, cognitive impairment, dementia, and stroke. Together, these disabilities may all be part of one large phenotype resulting from global cerebral microvascular dysfunction. In this review, we discuss the pathophysiology of microvascular dysfunction-related late-onset depression, summarize recent epidemiological evidence on the association between cerebral microvascular dysfunction and depression, and indicate potential drivers of cerebral microvascular dysfunction. We also propose the hypothesis that depression may be a manifestation of a larger phenotype of cerebral microvascular dysfunction, highlight potential therapeutic targets and interventions, and give directions for future research.

Association of Cerebral Artery Stenosis With Post-stroke Depression at Discharge and 3 Months After Ischemic Stroke Onset

Background: Post-stroke depression (PSD) is one of the most common complications after stroke, which seriously affects patients' recovery outcome. Although vascular depression has been extensively studied, the relationship between cerebral artery stenosis and PSD has not been clarified so far. Methods: Two hundred ninety-eight patients with ischemic stroke (72 women, 226 men) with computed tomography angiography (CTA) or magnetic resonance angiography (MRA) were included in this study. Cerebral artery stenosis ≥50% was used as the cut-off value. The DSM-V diagnostic criteria of PSD was met and the 17-item Hamilton Rating Scale for Depression (HAMD-17) score over 7 at discharge and 3 months after stroke onset was regarded as the primary outcome. The χ²-test, Mann-Whitney U-test, and t-test were used to check for statistical significance. Results: At discharge, Barthel index (p < 0.001), left middle cerebral artery stenosis (p = 0.019), drinking history (p = 0.048), basilar artery stenosis (p = 0.037) were significantly associated with PSD. At 3 months after ischemic stroke onset, Barthel index (p = 0.011), left middle cerebral artery stenosis (p = 0.012), female gender (p = 0.001) were significantly associated with PSD. Conclusions: The findings demonstrated that left middle cerebral artery and basilar artery stenosis are associated with PSD. It was suggested that cerebral artery stenosis was a risk factor of PSD and should be recognized and intervened early. Registration Number: ChiCTR-ROC-17013993.

Diabetes Mellitus-Related Fractional Glucose Uptake in Men and Women Imaged With 18F-FDG PET-CT

CONTEXT

Cohort studies show that cognitive dysfunction and both vascular and Alzheimer's dementia are more common in patients with type 2 diabetes mellitus (T2DM).

OBJECTIVE

To review and compare brain volume and 18F-fluorodeoxyglucose (FDG) uptake in brain of individuals age 60 to 70 years with or without type 2 diabetes.

DESIGN

We searched 620 medical records for negative 18FDG PET-CT scans obtained during 33 months. Records showing history of cognitive impairment, Alzheimer's disease, neurologic disorders, any history of brain atrophy, or documented cerebral infarction on neuroimaging were excluded from the study.

RESULTS

A total of 119 medical records met the inclusion criteria. Data from 63 women and 56 men (without T2DM, 86; with T2DM, 33) were analyzed. Brain volume was larger in men than women (mean ± SD, 1411 ± 225 cm3 vs 1325 ± 147 cm3, respectively; P = 0.02), but men had a significantly lower fractional glucose uptake (SUVgluc), calculated as fasting blood glucose × SUVmax. [median (minimum, maximum), 63.6 (34.6, 126.6) vs 70.0 (36.4, 134.3); P = 0.02]. Brain volume was also larger in persons without T2DM than in those with T2DM (1392 ± 172 cm3 vs 1269 ± 183 cm3; P < 0.001), but SUVgluc was similar between these groups. Brain volume correlated with SUVgluc in both men and women overall (P < 0.001) but not in men and women with T2DM (P = 0.20 and 0.36, respectively).

CONCLUSION

In men without T2DM, median brain volume was larger and fractional glucose uptake was less than in women without T2DM. In men and women with T2DM, brain volume and fractional glucose uptake were similar. The findings support the hypothesis that fractional glucose uptake becomes impaired in men with T2DM.

Comprehensive Cardiac Rehabilitation for Secondary Prevention After Transient Ischemic Attack or Mild Stroke: PSYCHOLOGICAL PROFILE AND OUTCOMES

PURPOSE

Having previously reported that comprehensive cardiac rehabilitation (CCR) is effective for secondary prevention post-transient ischemic attack (TIA)/mild nondisabling stroke (MNDS), we present psychometric findings for the same sample that elucidate subacute TIA/MNDS psychological outcomes and test whether CCR would be independently associated with psychological improvements.

METHODS

In this prospective cohort trial patients with ≥1 risk factor, recruited from a stroke prevention clinic within 12 months (mean = 11.5 weeks) post-TIA/MNDS, entered CCR.

RESULTS

Of the 110 recruited patients, 100 (mean age = 65.4 years; 46 females) entered CCR and 80 completed CCR (mean duration = 7.6 months). At CCR entry, 16.5% and 39.2% screened positively for depression and anxiety, decreasing nonsignificantly at exit to 4.2%, and significantly to 16.9% (P = .008), respectively. Age-corrected deficits occurred more frequently than expected (P ≤ .03); at entry, mental health status (13.3%), clock-drawing (31.6%), oral-verbal fluency (16.9%), word-list learning (11.2%), and recall (12.6%); at exit, clock-drawing (30.0%). Entry-to-exit, mean depression, anxiety, mental and physical health status, word-list learning, memory, digit-symbol coding, and oral-verbal fluency scores improved significantly (P ≤ .031). No reliable change indices were significant. Psychological service recipients improved significantly more than nonrecipients in depression (P = .049). Baseline North American Adult Reading Test score predicted exercise attendance (R = 0.275; P = .044); New York Heart Association (NYHA) class and depression score predicted exit physical health status (R = 0.770, P < .001); and depression score predicted exit mental health status (R = 0.523, P < .001).

CONCLUSIONS

Anxiety and executive dysfunction persisted post-TIA/MNDS. Although promising for secondary prevention post-TIA/MNDS, CCR was not independently associated with psychological improvements. CCR psychological treatment may benefit depression. Subacute NYHA class and depression may later affect quality of life.

Depression in people with type 2 diabetes: current perspectives

Type 2 diabetes mellitus (T2DM) is associated with depressive symptoms, and comorbid depression in those with T2DM has been associated with adverse clinical profiles. Recognizing and addressing psychological symptoms remain significant clinical challenges in T2DM. Possible mediators of the reciprocal relationship between T2DM and depression may include physical activity levels, effectiveness of self-management, distress associated with a new T2DM diagnosis, and frailty associated with advanced diabetes duration. The latter considerations contribute to a "J-shaped" trajectory from the time of diagnosis. There remain significant challenges to screening for clinical risks associated with psychological symptoms in T2DM; poorer outcomes may be associated with major depressive episodes, isolated (eg, anhedonic), or subsyndromal depressive symptoms, depressive-like symptoms more specific to T2DM (eg, diabetes-related distress), apathy or fatigue. In this review, we discuss current perspectives on depression in the context of T2DM with implications for screening and management of these highly comorbid conditions.

Frontocingulate cerebral blood flow and cerebrovascular reactivity associated with antidepressant response in late-life depression

BACKGROUND

Vascular pathology is common in late-life depression (LLD) and may contribute to alterations in cerebral blood flow (CBF) and cerebrovascular reactivity (CVR). In turn, such hemodynamic deficits may adversely affect brain function and clinical course. The goal of this study was to examine whether altered cerebral hemodynamics in depressed elders predicted antidepressant response.

METHODS

21 depressed elders completed cranial 3T MRI, including a pseudo-continuous Arterial Spin Labeling (pcASL) acquisition on both room air and during a hypercapnia challenge. Participants then completed 12 weeks of open-label sertraline. Statistical analyses examined the relationship between regional normalized CBF and CVR values and change in Montgomery-Asberg Depression Rating Scale (MADRS) and tested for differences based on remission status.

RESULTS

10 participants remitted and 11 did not. After controlling for age and baseline MADRS, greater change in MADRS with treatment was associated with lower pre-treatment normalized CBF in the caudal anterior cingulate cortex (cACC) and lateral orbitofrontal cortex (OFC), as well as lower CVR with hypercapnia in the caudal medial frontal gyrus (cMFG). After controlling for age and baseline MADRS score, remitters exhibited lower CBF in the cACC and lower CVR in the cMFG.

LIMITATIONS

Our sample was small, did not include a placebo arm, and we examined only specific regions of interest.

CONCLUSIONS

Our findings suggest that increased perfusion of the OFC and the ACC is associated with a poor antidepressant response. They do not support that vascular pathology as measured by CBF and CVR negatively affects acute treatment outcomes.

Can we clinically recognize a vascular depression? The role of personality in an expanded threshold model

The vascular depression (VD) hypothesis postulates that cerebrovascular disease may "predispose, precipitate, or perpetuate" a depressive syndrome in elderly patients. Clinical presentation of VD has been shown to differ to major depression in quantitative disability; however, as little research has been made toward qualitative phenomenological differences in the personality aspects of the symptom profile, clinical diagnosis remains a challenge.We attempted to identify differences in clinical presentation between depression patients (n = 50) with (n = 25) and without (n = 25) vascular disease using questionnaires to assess depression, affect regulation, object relations, aggressiveness, alexithymia, personality functioning, personality traits, and counter transference.We were able to show that patients with vascular dysfunction and depression exhibit significantly higher aggressive and auto-aggressive tendencies due to a lower tolerance threshold. These data indicate that VD is a separate clinical entity and secondly that the role of personality itself may be a component of the disease process. We propose an expanded threshold disease model incorporating personality functioning and mood changes. Such findings might also aid the development of a screening program, by serving as differential criteria, ameliorating the diagnostic procedure.

Reduced cerebral perfusion predicts greater depressive symptoms and cognitive dysfunction at a 1-year follow-up in patients with heart failure

OBJECTIVE

Cerebral hypoperfusion is common in heart failure (HF) and believed to underlie poor neurocognitive outcomes in this population. Up to 42% of HF patients also exhibit depressive symptomatology that may stem from reduced cerebral blood flow. However, no study has examined this possibility or whether reduced brain perfusion increases risk for future cognitive dysfunction in older adults with HF.

METHODS

One hundred HF patients underwent transcranial Doppler ultrasonagraphy to quantify global cerebral blood flow velocity (CBF-V) and were administered a cognitive test battery to assess global cognition, attention/executive function, and memory abilities. All participants then completed the Beck Depression Inventory-II to assess depressive symptomatology. These procedures were performed at baseline and at 12-month follow-up.

RESULTS

Repeated measures revealed that CBF-V declined over the 12-month period. Regression analyses showed that reduced baseline CBF-V predicted worse performances in attention/executive function (p < 0.05 for all) and a trend for memory (p = 0.09) in addition to greater depressive symptomatology (p < 0.05) at the 12-month follow-up, even after controlling for baseline factors and medical and demographic variables.

CONCLUSIONS

Cerebral perfusion declined over time and was associated with poorer cognitive function and greater depressive symptoms at a 1-year follow-up in HF. Prospective studies with long-term follow-ups that employ neuroimaging are needed to examine whether cognitive dysfunction and depression in HF stem from the adverse effects of cerebral hypoperfusion on the cerebral structure.

Tea consumption and depressive symptoms in older people in rural China

OBJECTIVES

To examine the association between tea consumption and depressive symptoms in Chinese older people and to explore the mediating role of cerebrovascular disease in the association.

DESIGN

Population-based cross-sectional study.

SETTING

A rural community near Qufu in Shandong, China.

PARTICIPANTS

Community-dwelling individuals aged 60 and older (mean 68.6; 59.3% female) from the Confucius Hometown Aging Project (N = 1,368).

MEASUREMENTS

Data were collected through interviews, clinical examinations, and psychological testing, following a standard procedure. Presence of high depressive symptoms was defined as a score of 5 or greater on the 15-item Geriatric Depression Scale.

RESULTS

Of the 1,368 participants, 165 (12.1%) were weekly and 489 (35.7%) were daily tea consumers. Compared with no or irregular tea consumption, controlling for age, sex, education, leisure activities, number of comorbidities, and Mini-Mental State Examination score, the odds ratios of having high depressive symptoms were 0.86 (95% confidence interval (CI) = 0.56-1.32) for weekly and 0.59 (95% CI = 0.43-0.81) for daily tea consumption (P for linear trend = .001); the linear trend of the association remained statistically significant when further controlling for history of stroke, transient ischemic attacks, and presence of carotid plaques.

CONCLUSIONS

Daily tea consumption is associated with a lower likelihood of depressive symptoms in Chinese older people living in a rural community. The association appears to be independent of cerebrovascular disease and atherosclerosis.

The vascular depression hypothesis: mechanisms linking vascular disease with depression

The 'Vascular Depression' hypothesis posits that cerebrovascular disease may predispose, precipitate or perpetuate some geriatric depressive syndromes. This hypothesis stimulated much research that has improved our understanding of the complex relationships between late-life depression (LLD), vascular risk factors, and cognition. Succinctly, there are well-established relationships between LLD, vascular risk factors and cerebral hyperintensities, the radiological hallmark of vascular depression. Cognitive dysfunction is common in LLD, particularly executive dysfunction, a finding predictive of poor antidepressant response. Over time, progression of hyperintensities and cognitive deficits predicts a poor course of depression and may reflect underlying worsening of vascular disease. This work laid the foundation for examining the mechanisms by which vascular disease influences brain circuits and influences the development and course of depression. We review data testing the vascular depression hypothesis with a focus on identifying potential underlying vascular mechanisms. We propose a disconnection hypothesis, wherein focal vascular damage and white matter lesion location is a crucial factor, influencing neural connectivity that contributes to clinical symptomatology. We also propose inflammatory and hypoperfusion hypotheses, concepts that link underlying vascular processes with adverse effects on brain function that influence the development of depression. Testing such hypotheses will not only inform the relationship between vascular disease and depression, but also provide guidance on the potential repurposing of pharmacological agents that may improve LLD outcomes.

Not all depression is created equal: sex interacts with disease to precipitate depression

Depression is a common mental disorder that co-occurs in other neurological and somatic diseases. Further, sex differences exist in the prevalence rates of many of these diseases, as well as within non-disease associated depression. In this review, the case is made for needing a better recognition of the source of the symptoms of depression with respect to the sex of the individual; in that, some disease states, which includes the neuroendocrine and immune reactions to the underlying pathophysiology of the disease, may initiate depressive symptoms more often in one sex over the other. The diseases specifically addressed to make this argument are: epilepsy, Alzheimer’s disease, cancer, and cardiovascular disease. For each of these conditions, a review of the following are presented: prevalence rates of the conditions within each sex, prevalence rates of depressive symptoms within the conditions, identified relationships to gonadal hormones, and possible interactions between gonadal hormones, adrenal hormones, and immune signaling. Conclusions are drawn suggesting that an evaluation of the root causes for depressive symptoms in patients with these conditions is necessary, as the underlying mechanisms for eliciting the depressive symptoms may be qualitatively different across the four diseases discussed. This review attempts to identify and understand the mechanisms of depression associated with these diseases, in the context of the known sex differences in the disease prevalence and its age of onset. Hence, more extensive, sex-specific model systems are warranted that utilize these disease states to elicit depressive symptoms in order to create more focused, efficient, and sex-specific treatments for patients suffering from these diseases and concurrent depressive symptoms.

Cerebral hemodynamics and incident depression: the Rotterdam Study

BACKGROUND

According to the vascular depression hypothesis, subclinical cerebrovascular disease can cause depression in older adults. To test this hypothesis, several cross-sectional studies have assessed structural brain parameters, but few have examined hemodynamic alterations in the brain.

METHODS

From the Rotterdam Study, we studied a cohort of 1494 participants (65+ years of age) free of depression, dementia, and stroke at baseline. In the middle cerebral artery blood flow velocities and vasomotor reactivity were measured with transcranial Doppler ultrasonography. All participants were repeatedly assessed for depressive symptoms with Centre for Epidemiological Studies-Depression scale (CES-D). Participants with depressive symptoms (CES-D ≥16) had a semi-structured interview, to classify the depression according to DSM-IV criteria. All analyses were adjusted for sociodemographic data, vascular risk factors, and incident stroke.

RESULTS

Lower peak-systolic, end-diastolic, and mean blood flow velocities at baseline were associated with higher CES-D scale scores at follow-up. Mean blood flow velocity predicted incident depressive symptoms (odds ratio [OR]: .74, 95% confidence interval [CI]: .60-.91, p = .004) and depressive disorders (OR: .83, 95% CI: .69-.98, p = .032), whereas decreased baseline vasomotor reactivity predicted incident depressive disorders only (OR: .66, 95% CI: .53-.83, p < .001).

CONCLUSIONS

Lower blood flow velocity, indicating reduced cerebral metabolism, predicted depressive symptoms and depressive disorders. Reduced vasomotor reactivity, which might indicate cerebral microangiopathy, predicted depressive disorders only, in healthy older adults. These findings provide prospective evidence for vascular depression hypothesis.

Improved Cerebral Vasomotor Reactivity After Exercise Training in Hemiparetic Stroke Survivors

Background and Purpose—

Animal studies provide strong evidence that aerobic exercise training positively influences cerebral blood flow, but no human studies support the use of exercise for improving cerebral hemodynamics. This randomized study in stroke survivors assessed the effects of treadmill aerobic exercise training (TM) on cerebral blood flow parameters compared to a control intervention of nonaerobic stretching.

Methods—

Thirty-eight participants (19 in TM group and 19 in control group) with remote stroke (>6 months) and mild to moderate gait deficits completed middle cerebral artery blood flow velocity measurements by transcranial Doppler ultrasonography before and after a 6-month intervention period. Middle cerebral artery blood flow velocity was assessed bilaterally during normocapnia and hypercapnia (6% CO 2 ). Cerebral vasomotor reactivity (cVMR) was calculated as percent change in middle cerebral artery blood flow velocity from normocapnia to hypercapnia (cVMR percent) and as an index correcting percent change for absolute increase in end tidal CO 2 (cVMR index).

Results—

The TM group had significantly larger improvements than did controls for both ipsilesional and contralesional cVMR index ( P ≤0.05) and contralesional cVMR percent ( P ≤0.01). Statin users in the TM group (n=10) had higher baseline cVMR and lower training-induced cVMR change, indicating that cVMR change among those not using statins (n=9) primarily accounted for the between-group effects. There was a 19% increase in V o 2 peak for the TM group compared to a 4% decrease in the control group ( P <0.01), and peak fitness change correlated with cVMR change ( r =0.55; P <0.05).

Conclusions—

Our data provide the first evidence to our knowledge of exercise-induced cVMR improvements in stroke survivors, implying a protective mechanism against recurrent stroke and other brain-related disorders. Statin use appears to regulate cVMR and the cVMR training response.

Hypertension and cerebral vasoreactivity: a continuous arterial spin labeling magnetic resonance imaging study

Hypertension is associated with microvascular and macrovascular brain injury but its direct influence on the cerebral circulation is not fully clear. Our objective was to investigate the association of hypertension with global and regional cerebral vasoreactivity to CO(2) using continuous arterial spin labeling MRI, independent of stroke and white matter hyperintensities. Participants (n=62; mean age: 66.7±1.0 years, 55% women, 84% white, 65% hypertension, 47% stroke) underwent arterial spin labeling perfusion MRI during normal breathing, 5% CO(2) rebreathing, and hyperventilation, as well as 24-hour ambulatory blood pressure monitoring. Vasoreactivity was the slope of the regression between cerebral perfusion and end-tidal CO(2). White matter hyperintensity volumes were quantified. Nighttime dipping was calculated as the percentage decline in nighttime/daytime blood pressure. After accounting for stroke and white matter hyperintensity volume, hypertensive participants had lower global vasoreactivity (1.11±0.13 versus 0.43±0.1 mL/100 g per minute per millimeter of mercury; P=0.0012). Regionally, this was significant in the frontal, temporal, and parietal lobes. Higher mean systolic blood pressure was associated with lower vasoreactivity (decreased by 0.11 U/10-mm Hg increase in systolic blood pressure; P=0.04), but nighttime dipping was not (P=0.2). The magnitude of decrease in vasoreactivity in hypertension without stroke was comparable to the magnitude of decrease in vasoreactivity in stroke without hypertension. Hypertension has a direct negative effect on the cerebrovascular circulation independent of white matter hyperintensities and stroke that is comparable to that seen with stroke. Because lower vasoreactivity is associated with poor outcomes, studies of the impact of antihypertensive on vasoreactivity are important.

The NIH Cognitive and Emotional Health Project. Report of the Critical Evaluation Study Committee

BACKGROUND

The Cognitive and Emotional Health Project (CEHP) seeks to identify the demographic, social, and biological determinants of cognitive and emotional health in the older adult. As part of the CEHP, a critical evaluation study committee was formed to assess the state of epidemiological research on demographic, social, and biological determinants of cognitive and emotional health.

METHODS

Criteria for inclusion in the survey were large cohort studies, longitudinal in design, participants predominantly 65 years or older, with measurements of both cognition and emotion, and information on a wide variety of demographic, psychosocial, and biological factors. North American and European studies, which met these criteria, were selected for the review. Outcome measures included cognition, cognitive decline, and cognitive function. For emotion, symptoms included depression and anxiety, positive and negative affect, subjective well being, mastery, and resilience.

RESULTS

Ninety-six papers were identified that addressed cognitive and emotional outcomes. A large variety of risk factors were consistently identified with cognitive outcomes, particularly those previously associated with increased risk of cardiovascular disease. There was considerable overlap between risk factors for cognitive and emotional outcomes.

CONCLUSION

This review identifies a large number of lifestyle and health behaviors that alter the risk for maintenance of cognitive and emotional health. Large longitudinal cohort studies are a unique source to explore factors associated with cognitive and emotional health. Secondary analyses of these studies should be encouraged as should the development of standardized questionnaires to measure cognitive and emotional health. Future research in this field should study cognitive and emotional health simultaneously.

Effects of central arterial aging on the structure and function of the peripheral vasculature: implications for end-organ damage

Over the past decade, numerous studies have shown that increased aortic stiffness is associated with major cardiovascular disease end points, including heart disease, stroke, and kidney disease. Cardiac abnormalities and enhanced atherogenesis in the setting of increased pulsatile load on heart and arteries have been well described. However, recent studies have shown a further association between excessive pressure pulsatility and a number of afflictions of aging that share a predominant microvascular etiology, including many forms of kidney disease and cognitive impairment. In these disorders, microvascular remodeling and impaired regulation of local blood flow, which are related to large artery stiffness and pressure pulsatility, are associated with evidence of diffuse microscopic tissue damage. This brief review will summarize age-related changes in aortic and peripheral vascular function and will discuss potential mechanisms leading from changes in properties of large arteries to excessive pressure pulsatility, abnormal microvascular structure and function, and end-organ dysfunction and damage.

Biomarkers of cerebrovascular disease in dementia

There is increasing recognition that cerebrovascular disease contributes significantly to the development and progression of patients with dementia. The concepts of pure vascular and pure degenerative dementia have been replaced with a recognition that, in many patients, there is a spectrum of neurodegenerative and vascular processes. This is supported by preliminary studies showing response to vascular therapeutics and ventriculo-peritoneal shunting in patients with Alzheimer's disease. This article examines the imaging biomarkers that are available for the characterization of microvascular abnormality in the ageing brain, with particular reference to microvascular angiopathy, cerebral embolic disease, orthostatic hypotension and abnormalities of Monro-Kellie homeostasis.

Relationship between age at onset and magnetic resonance image-defined hyperintensities in mood disorders

OBJECTIVES

To examine in patients with mood disorders the relationship of age at onset with the location and degree of MRI-defined brain hyperintensities.

METHOD

Fifty-two patients diagnosed as having mood disorders and 14 controls participated in the study. Brain MR images were analyzed according to semiquantitative ratings for the anatomical distribution and severity of T2-weighted hyperintensities. We compared these hyperintensities among the three age- and sex-matched groups of late-onset mood disorder patients (LOM), early-onset mood disorder patients (EOM), and controls. The time since the onset of disorder was significantly longer in the EOM than in the LOM group. We also conducted linear multiple regression analysis using the severity of hyperintensities as dependent variable to determine whether the clinical features correlate with vascular pathology.

RESULTS

As for deep white matter hyperintensity (DWMH), LOM exhibited higher ratings than EOM; as for brain areas, significant between-group differences were detected in the bilateral frontal areas and in the left parieto-occipital area. No significant difference was observed between EOM and controls. As for periventricular hyperintensity, there was no difference among the three groups. We obtained a significant regression model to predict DWMH ratings; age, number of ECTs, and LOM were selected as significant variables.

CONCLUSION

The present study suggests that the time since the onset of disorder does not affect the development of white matter lesions, but that white matter lesions are associated with late-onset mood disorders. The frontal areas and the left parieto-occipital area would be important for the development of late-onset mood disorders.

The Rotterdam Study: objectives and design update

The Rotterdam Study is a prospective cohort study ongoing since 1990 in the city of Rotterdam in the Netherlands. The study targets cardiovascular, neurological, ophthalmological and endocrine diseases. As of 2008 about 15,000 subjects aged 45 years or over comprise the Rotterdam Study cohort. The findings of the Rotterdam Study have been presented in some 600 research articles and reports (see http://www.epib.nl/rotterdamstudy). This article gives the reasons for the study and its design. It also presents a summary of the major findings and an update of the objectives and methods.

Effects of citalopram and fluoxetine on the corticocerebral blood flow in conscious rabbits

Depression, which is associated with an increased incidence of vascular events, frequently occurs following stroke. Selective serotonin reuptake inhibitory drugs (SSRIs) as antidepressants, are well tolerated, and also seem to be effective in post-stroke depression. The aim of this study was to investigate the effects of the SSRIs citalopram and fluoxetine, on the corticocerebral blood flow (cCBF) in rabbits with unilateral carotid occlusion induced cerebral ischemia. The cCBF was measured by the hydrogen clearance technique. After determination of the mean baseline cCBF, the effects of individual doses (0.1, 0.3 and I mg/kg) of citalopram or fluoxetine on the cCBF were investigated. Following the induction of an impaired cCBF, the changes in cCBF after drug treatments in this condition were likewise measured. The mean arterial blood pressure (MABP) and the heart rate (HR) from the electrocardiogram (ECG) were also determined. Neither citalopram nor fluoxetine influenced the cCBF in the control group. Fluoxetine improved the cCBF only very slightly in the ischemic animals. In contrast, all the doses of citalopram exerted pronounced and dose-dependent cCBF-increasing effects in the animals with unilateral carotid occlusion (maximal mean ACBF: 10, 16 and 27 ml/min/100 g tissue). The HR was decreased in both groups. Only citalopram treatment led to a slight MABP-decreasing effect. Besides enhancement of the serotonergic transmission in the brain, the cCBF-increasing effect of citalopram under ischemic conditions may be of benefit in post-stroke and vascular depression.

Abnormalities of CSF flow patterns in the cerebral aqueduct in treatment-resistant late-life depression: a potential biomarker of microvascular angiopathy

There is growing evidence that microvascular angiopathy (MVA) plays an important role in the development of dementia and affective disorders in older people. At currently available image resolutions it is not possible to image directly the vascular changes associated with MVA, but the effects on blood and cerebrospinal fluid (CSF) flow may be detectable. The aim of this study was to investigate a potential biomarker for MVA based on MRI of abnormalities in CSF flow. Since there is considerable indirect evidence that treatment resistance in late-onset depressive disorder is related to MVA, we assessed the method in a group of 22 normal volunteers and 29 patients with responsive (N=21) or treatment-resistant (N=8) late-onset depressive disorder. Single-slice quantified phase-contrast (PC) images of cerebral blood and CSF flow were collected at 15 points over a cardiac cycle, and the resulting flow curves were parameterized. Significant differences in the CSF flow (width of systolic flow peak and diastolic flow volume, both P<0.01) through the cerebral aqueduct were observed for the group of treatment-resistant patients when compared to age matched controls. No significant difference was observed for a group of 21 patients with treatment-responsive depression. The findings support the hypothesis that MR measurement of CSF flow abnormalities provides a biomarker of MVA, and thus could have application in a wide range of age-related diseases.

Arterial blood flow to the brain in patients with vascular disease: the SMART Study

PURPOSE

To retrospectively investigate which characteristics are related to total arterial blood flow to the brain in patients with symptomatic vascular disease.

MATERIALS AND METHODS

The study was approved by the ethics committee of the authors' institution, and written informed consent was obtained. The total volume flow rate (tVFR) values in the internal carotid arteries and the basilar artery in 636 patients (536 men, 100 women; mean age, 58 years) with symptomatic vascular disease were measured with two-dimensional phase-contrast magnetic resonance (MR) angiography. Reference tVFR values in the general population were obtained from previous research involving 158 subjects (73 men, 85 women; mean age, 60 years).

RESULTS

A higher tVFR was found in patients with symptomatic vascular disease, but this association was statistically significant in only those patients in the 7th decade of life. The mean tVFR decreased with increasing age (-3.4 mL/min per year; 95% confidence interval [CI]: -4.3, -2.5). Diabetes (-27.6 mL/min; 95% CI: -52.6, -2.6) and increasing body mass index (BMI) (-2.8 mL/min per BMI unit; 95% CI: -5.3, -0.2) were associated with lower tVFR. Patients with vascular disease in a cerebral location had lower tVFR values (-39.7 mL/min; 95% CI: -65.1, -14.3) than did patients with symptomatic vascular disease elsewhere in the vascular tree.

CONCLUSION

Patients with symptomatic vascular disease had slightly higher arterial blood flow to the brain compared with the general population. The tVFR decreased with increasing age and increasing BMI, and patients with diabetes had lower tVFR values than did those without diabetes. Patients with vascular disease in a cerebral location had lower tVFR values than did those with symptomatic vascular disease at other arterial sites.

Relationship between oxygen supply and cerebral blood flow assessed by transcranial Doppler and near-infrared spectroscopy in healthy subjects during breath-holding

Background

Breath – holding (BH) is a suitable method for inducing cerebral vasomotor reactivity (VMR). The assessment of VMR is of clinical importance for the early detection of risk conditions and for the follow-up of disabled patients. Transcranial Doppler ultrasonography (TCD) is used to measure cerebral blood flow velocity (CBFV) during BH, whereas near-infrared spectroscopy (NIRS) measures the concentrations of the oxygenated (O₂Hb) and reduced (CO₂Hb) hemoglobin. The two techniques provide circulatory and functional-related parameters. The aim of the study is the analysis of the relationship between oxygen supply and CBFV as detected by TCD and NIRS in healthy subjects performing BH.

Methods

20 healthy subjects (15 males and 5 females, age 33 ± 4.5 years) underwent TCD and NIRS examination during voluntary breath – holding. VMR was quantified by means of the breath-holding index (BHI). We evaluated the BHI based on mean CBFV, O₂Hb and CO₂Hb concentrations, relating the baseline to post-stimulus values. To quantify VMR we also computed the slope of the linear regression line of the concentration signals during BH. From the NIRS signals we also derived the bidimensional representation of VMR, plotting the instantaneous O₂Hb concentration vs the CO₂Hb concentration during the BH phase. Two subjects, a 30 years old current smoker female and a 63 years old male with a ischemic stroke event at the left middle cerebral artery, were tested as case studies.

Results

The BHI for the CBFV was equal to 1.28 ± 0.71 %/s, the BHI for the O₂Hb to 0.055 ± 0.037 μmol/l/s and the BHI for CO₂Hb to 0.0006 ± 0.0019 μmol/l/s, the O₂Hb slope was equal to 0.15 ± 0.09 μmol/l/s and the CO₂Hb slope to 0.09 ± 0.04 μmol/l/s. There was a positive correlation between the CBFV and the O₂Hb increments during BH (r = 0.865). The bidimensional VMR pattern shows common features among healthy subjects that are lost in the control studies.

Conclusion

We show that healthy subjects present a common VMR pattern when counteracting cerebral blood flow perturbations induced by voluntary BH. The proposed methodology allows for the monitoring of changes in the VMR pattern, hence it could be used for assessing the efficacy of neurorehabilitation protocols.

Technical note: the swimmer's view for cervical facet joint injections

Image intensifier (C-arm) guided facet infiltration of a mixture of long acting local anaesthetic and corticosteroid is a safe and effective office procedure for cervical spondylosis. Visualisation of lower cervical anatomy using C-arm may not always be possible due to the shadow cast by the shoulders. We describe the successful adaptation of swimmer's view in such cases to carry out the injections.

Hypofrontality and microvascular dysregulation in remitted late-onset depression assessed by functional near-infrared spectroscopy

Accumulated evidence suggests the involvement of vascular factors in late-onset depression. Late-onset depression has characteristics of poor outcome, cognitive decline, and high prevalence rather than early-onset depression. The aim of the present study was to determine whether or not the functional hypofrontality--that is, hypoperfusion and hypometabolism in the frontal lobes-seen in late-onset depression is a trait-dependent abnormality of microvascular regulation. This study was conducted on 10 patients with remitted late-onset major depressive disorder (MDD) and 10 healthy volunteers matched for vascular factors and subcortical, or white matter, hyperintensities (WMH). Using near-infrared spectroscopy combined with magnetic resonance imaging, we investigated the microvascular reactivity in the prefrontal cortex during a cognitive task and during carbon dioxide (CO(2)) inhalation. Activation of the prefrontal cortex during the cognitive task was significantly less in patients as compared with controls, although task performance was not significantly different between the two groups. In the patients, a tendency of negative correlation between the reduced prefrontal activation during a cognitive task and the severity of hyperintensity in periventricular region was observed. Vasomotor reactivity to CO(2) inhalation was significantly lower in the patients than in the controls. Although there was no significant association between the activation during the cognitive and that during the CO(2) inhalation task, the present results suggest that prefrontal microvascular dysregulation as shown by NIRS is involved in the pathophysiological basis of functional hypofrontality in late-onset depression. This finding will provide a new framework for the development of diagnostic methods, treatments, and preventive strategies against late-onset depression.

Is vascular depression a distinct sub-type of depressive disorder? A review of causal evidence

BACKGROUND

Vascular depression is an important conceptual and clinical concept.

OBJECTIVE

To apply criteria which, in an ideal world, should be satisfied before an association between depression and vascular disease can be considered robust.

METHOD

A literature review with discussion of findings in the light of recently suggested guidelines for the development of new psychiatric disorders.

RESULTS

There is considerable evidence linking depression in later life with vascular brain disease but the interaction is bi-directional. Depression and vascular disease could be mediated by factors other than traditional vascular risk factors. There is increasing interest in mechanisms such as inflammatory processes which may mediate both depression and vascular disease.

CONCLUSIONS

Vascular depression provides a useful framework with which to remind the clinician of important interactions between depression and vascular disease but conceptually it may be too restrictive.

Cerebral Haemodynamics in the Elderly: The Rotterdam Study

Transcranial Doppler ultrasonography allows the non-invasive assessment of cerebral haemodynamics. Data on the frequency distribution of these parameters in the oldest old are scarce, which makes a distinction between physiological and pathophysiological ageing difficult. We studied the relation between cerebral haemodynamic parameters and age and sex in 1,720 participants of a population-based study by means of transcranial Doppler ultrasonography. The end-diastolic, peak systolic and mean cerebral blood flow velocity, and cerebrovascular CO2 reactivity declined significantly with increasing age up to 90 years (per year -0.6 cm/s; -0.3 cm/s; -0.5 cm/s, and -0.6%/kPa, respectively). The pulsatility index increased with age (per year 0.01). End-diastolic, peak systolic and mean cerebral blood flow velocities were lower in men compared to women (age-adjusted difference 1.6 cm/s; 4.1 cm/s, and 2.5 cm/s, respectively). Cerebrovascular CO2 reactivity was higher in men compared to women. Adjusting for carotid atherosclerosis did not change the observed sex differences. These findings provide insight into physiologic changes of haemodynamics during ageing and may serve as a starting point for investigations on determinants of pathophysiologic changes in cerebral haemodynamics in the elderly.