Retinal microvascular function and incidence and trajectories of clinically relevant depressive symptoms: the Maastricht Study.

BACKGROUND: Cerebral microvascular dysfunction may contribute to depression via disruption of brain structures involved in mood regulation, but evidence is limited. We investigated the association of retinal microvascular function, a proxy for microvascular function in the brain, with incidence and trajectories of clinically relevant depressive symptoms. METHODS: Longitudinal data are from The Maastricht Study of 5952 participants (59.9 ± 8.5 years/49.7% women) without clinically relevant depressive symptoms at baseline (2010-2017). Central retinal arteriolar equivalent and central retinal venular equivalent (CRAE and CRVE) and a composite score of flicker light-induced retinal arteriolar and venular dilation were assessed at baseline. We assessed incidence and trajectories of clinically relevant depressive symptoms (9-item Patient Health Questionnaire score ⩾10). Trajectories included continuously low prevalence (low, n = 5225 [87.8%]); early increasing, then chronic high prevalence (early-chronic, n = 157 [2.6%]); low, then increasing prevalence (late-increasing, n = 247 [4.2%]); and remitting prevalence (remitting, n = 323 [5.4%]). RESULTS: After a median follow-up of 7.0 years (range 1.0-11.0), 806 (13.5%) individuals had incident clinically relevant depressive symptoms. After full adjustment, a larger CRAE and CRVE were each associated with a lower risk of clinically relevant depressive symptoms (hazard ratios [HRs] per standard deviation [s.d.]: 0.89 [95% confidence interval (CI) 0.83-0.96] and 0.93 [0.86-0.99], respectively), while a lower flicker light-induced retinal dilation was associated with a higher risk of clinically relevant depressive symptoms (HR per s.d.: 1.10 [1.01-1.20]). Compared to the low trajectory, a larger CRAE was associated with lower odds of belonging to the early-chronic trajectory (OR: 0.83 [0.69-0.99]) and a lower flicker light-induced retinal dilation was associated with higher odds of belonging to the remitting trajectory (OR: 1.23 [1.07-1.43]). CONCLUSIONS: These findings support the hypothesis that cerebral microvascular dysfunction contributes to the development of depressive symptoms.

Age at cardiovascular disease onset, dementia risk, and the role of lifestyle factors.

INTRODUCTION: We first examined the role of age at cardiovascular disease (CVD) onset for incident dementia, and then examined whether lifestyle factors at guideline-recommended levels in individuals with CVD mitigates dementia risk. METHODS: We used population-based data (Whitehall II: n = 10,308/baseline 1985-1988/examinations every 4-5 years). Lifestyle factors (non-smoking, body mass index [BMI], physical activity, diet) were extracted post-CVD. RESULTS: Over a median of 31.6 years, 3275 (32.1%) developed CVD. At age 70, risk of dementia was higher in individuals with CVD onset before (hazard ratio [HR] of incident dementia for participants with CVD before age 60, using participants without CVD at age 70 as the reference: 1.56, 95% confidence interal [CI] 1.18-2.08) but not after 60 years. In participants with CVD, a greater number of lifestyle factors at recommended levels post-CVD was associated with a lower dementia risk (per lifestyle factor at recommended level HR: 0.73, 95% CI 0.59-0.92). DISCUSSION: Our results suggest that early onset CVD is associated with a higher dementia risk at older ages. In those with CVD, the dementia risk was lower if lifestyle factors are at recommended levels following CVD diagnosis. HIGHLIGHTS: CVD in midlife but not in late life is associated with a higher risk of dementia. Dementia risk in CVD patients is lower if their lifestyle factors are at recommended levels. These findings provide evidence to promote CVD prevention in midlife or earlier. Study findings also show the importance of a healthy lifestyle in those with CVD.

Retinal Microvascular Caliber and Incident Depressive Symptoms: The Multi-Ethnic Study of Atherosclerosis.

Cerebral microvascular dysfunction may contribute to depression via disruption of brain structures involved in mood regulation, but evidence is limited. The retina allows for visualization of a microvascular bed that shares similarities with the cerebral microvasculature. We investigated the associations between baseline retinal arteriolar and venular calibers (central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE), respectively) and incident depressive symptoms in the Multi-Ethnic Study of Atherosclerosis (MESA). We used longitudinal data on 4,366 participants (mean age = 63.2 years; 48.5% women, 28.4% Black) without baseline depressive symptoms. Depressive symptoms, defined as Center for Epidemiologic Studies Depression Scale score ≥16 and/or use of antidepressant medication, were determined between 2002 and 2004 (baseline; MESA visit 2) and at 3 follow-up examinations conducted every 1.5-2 years thereafter. Fundus photography was performed at baseline. After a mean follow-up period of 6.1 years, 21.9% (n = 958) had incident depressive symptoms. After adjustment for sociodemographic, lifestyle, and cardiovascular factors, a 1-standard-deviation larger baseline CRVE was associated with a higher risk of depressive symptoms (hazard ratio = 1.10, 95% confidence interval: 1.02, 1.17), and a 1-standard-deviation larger baseline CRAE was not statistically significantly associated with incident depressive symptoms (hazard ratio = 1.04, 95% confidence interval: 0.97, 1.11). In this study, larger baseline CRVE, but not CRAE, was associated with a higher incidence of depressive symptoms.

Associations of plasma NfL, GFAP, and t-tau with cerebral small vessel disease and incident dementia: longitudinal data of the AGES-Reykjavik Study.

We investigated the associations of plasma neurofilament light (NfL), glial fibrillary acidic protein (GFAP), and total tau (t-tau) with markers of cerebral small vessel disease (SVD) and with incident dementia. We also investigated whether associations of NfL, GFAP, and t-tau with incident dementia were explained by SVD. Data are from a random subsample (n = 1069) of the population-based AGES-Reykjavik Study who underwent brain MRI and in whom plasma NfL, GFAP, and t-tau were measured at baseline (76.1 ± 5.4 years/55.9% women/baseline 2002-2006/follow-up until 2015). A composite SVD burden score was calculated using white matter hyperintensity volume (WMHV), subcortical infarcts, cerebral microbleeds, and large perivascular spaces. Dementia was assessed in a 3-step process and adjudicated by specialists. Higher NfL was associated with a higher SVD burden score. Dementia occurred in 225 (21.0%) individuals. The SVD burden score significantly explained part of the association between NfL and incident dementia. WMHV mostly strongly contributed to the explained effect. GFAP was not associated with the SVD burden score, but was associated with WMHV, and WMHV significantly explained part of the association between GFAP and incident dementia. T-tau was associated with WMHV, but not with incident dementia. In conclusion, the marker most strongly related to SVD is plasma NfL, for which the association with WMHV appeared to explain part of its association with incident dementia. This study suggests that plasma NfL may reflect the contribution of co-morbid vascular disease to dementia. However, the magnitude of the explained effect was relatively small, and further research is required to investigate the clinical implications of this finding.

Microvascular Dysfunction and Whole-Brain White Matter Connectivity: The Maastricht Study.

BACKGROUND: Microvascular dysfunction is involved in the development of various cerebral disorders. It may contribute to these disorders by disrupting white matter tracts and altering brain connectivity, but evidence is scarce. We investigated the association between multiple biomarkers of microvascular function and whole-brain white matter connectivity. METHODS AND RESULTS: Cross-sectional data from The Maastricht Study, a Dutch population-based cohort (n=4326; age, 59.4±8.6 years; 49.7% women). Measures of microvascular function included urinary albumin excretion, central retinal arteriolar and venular calibers, composite scores of flicker light-induced retinal arteriolar and venular dilation, and plasma biomarkers of endothelial dysfunction (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, and von Willebrand factor). White matter connectivity was calculated from 3T diffusion magnetic resonance imaging to quantify the number (average node degree) and organization (characteristic path length, global efficiency, clustering coefficient, and local efficiency) of white matter connections. A higher plasma biomarkers of endothelial dysfunction composite score was associated with a longer characteristic path length (ß per SD, 0.066 [95% CI, 0.017-0.114]) after adjustment for sociodemographic, lifestyle, and cardiovascular factors but not with any of the other white matter connectivity measures. After multiple comparison correction, this association was nonsignificant. None of the other microvascular function measures were associated with any of the connectivity measures. CONCLUSIONS: These findings suggest that microvascular dysfunction as measured by indirect markers is not associated with whole-brain white matter connectivity.

Association of type 2 diabetes according to the number of risk factors within the recommended range with incidence of major depression and clinically relevant depressive symptoms: a prospective analysis.

BACKGROUND: Type 2 diabetes is associated with an increased risk of depression, but the extent to which risk factor modification can mitigate this risk is unclear. We aimed to examine the association between the incidence of major depression and clinically relevant depressive symptoms among individuals with type 2 diabetes, according to the number of risk factors within the recommended target range, compared with individuals without diabetes. METHODS: We did a prospective analysis of population-based data from the UK Biobank and the Maastricht Study. Individuals with type 2 diabetes were categorised according to the number of risk factors within the recommended target range (non-smoking, guideline-recommended levels of glycated haemoglobin (HbA1c), blood pressure, BMI, albuminuria, physical activity, and diet). The primary outcome, based on data from the UK Biobank, was the incidence of major depression ascertained from hospital records; the secondary outcome, based on data from the UK Biobank and the Maastricht Study, was clinically relevant depressive symptoms based on a score of 10 or higher on the Patient Health Questionnaire (PHQ-9). FINDINGS: The study population of the UK Biobank comprised 77 786 individuals (9047 with type 2 diabetes and 68 739 without diabetes; median age 59 years [IQR 51-64]; 34 136 [43·9%] women and 43 650 [56·1%] men). A median of 12·7 years (IQR 11·8-13·4) after recruitment (between March 13, 2006, and Oct 1, 2010), 493 (5·5%) of 9047 individuals with type 2 diabetes and 2574 (3·7%) of 68 739 individuals without diabetes developed major depression. Compared with individuals without diabetes, those with type 2 diabetes had a higher risk of major depression (hazard ratio [HR] 1·61 [95% CI 1·49-1·77]). Among individuals with type 2 diabetes, the excess risk of depression decreased stepwise with an increasing number of risk factors within the recommended target range (HR 2·04 [95% CI 1·65-2·52] for up to two risk factors within the recommended target range; 1·95 [1·65-2·30] for three risk factors within the recommended target range; 1·38 [1·16-1·65] for four risk factors within the recommended target range; and 1·34 [1·12-1·62] for five to seven risk factors within the recommended target range). In the UK Biobank dataset, a median of 7·5 years (IQR 6·8-8·2) after the baseline examination, 147 (7·5%) of 1953 individuals with type 2 diabetes and 954 (4·5%) of 21 413 individuals without diabetes had developed clinically relevant depressive symptoms. The study population of the Maastricht Study comprised 4530 individuals (1158 with type 2 diabetes and 3372 without diabetes; median age 60 years [IQR 53-66]; 2244 [49·5%] women and 2286 [50·1%] men). A median of 5·1 years (IQR 4·1-6·1) after recruitment (between Sept 1, 2010, and Dec 7, 2017), 170 (14·7%) of 1158 individuals with type 2 diabetes and 227 (6·7%) of 3372 individuals without diabetes developed clinically relevant depressive symptoms. Similarly, in both the UK Biobank dataset and the Maastricht Study cohort, among individuals with type 2 diabetes, the excess risk of clinically relevant depressive symptoms decreased stepwise with an increasing number of risk factors within the recommended target range. INTERPRETATION: Among individuals with type 2 diabetes, the excess risk of major depression and clinically relevant depressive symptoms decreased stepwise with an increasing number of risk factors within the recommended target range. This study provides further evidence to promote risk factor modification strategies in individuals with type 2 diabetes and to encourage the adoption of a healthy lifestyle. FUNDING: ZonMW, Hartstichting, and Diabetes Fonds.

Identification of physical activity and sedentary behaviour dimensions that predict mortality risk in older adults: Development of a machine learning model in the Whitehall II accelerometer sub-study and external validation in the CoLaus study.

Background: Identification of new physical activity (PA) and sedentary behaviour (SB) features relevant for health at older age is important to diversify PA targets in guidelines, as older adults rarely adhere to current recommendations focusing on total duration. We aimed to identify accelerometer-derived dimensions of movement behaviours that predict mortality risk in older populations. Methods: We used data on 21 accelerometer-derived features of daily movement behaviours in 3991 participants of the UK-based Whitehall II accelerometer sub-study (25.8% women, 60-83 years, follow-up: 2012-2013 to 2021, mean = 8.3 years). A machine-learning procedure was used to identify core PA and SB features predicting mortality risk and derive a composite score. We estimated the added predictive value of the score compared to traditional sociodemographic, behavioural, and health-related risk factors. External validation in the Switzerland-based CoLaus study (N = 1329, 56.7% women, 60-86 years, follow-up: 2014-2017 to 2021, mean = 3.8 years) was conducted. Findings: In total, 11 features related to overall activity level, intensity distribution, bouts duration, frequency, and total duration of PA and SB, were identified as predictors of mortality in older adults and included in a composite score. Both in the derivation and validation cohorts, the score was associated with mortality (hazard ratio = 1.10 (95% confidence interval = 1.05-1.15) and 1.18 (1.10-1.26), respectively) and improved the predictive value of a model including traditional risk factors (increase in C-index = 0.007 (0.002-0.014) and 0.029 (0.002-0.055), respectively). Interpretation: The identified accelerometer-derived PA and SB features, beyond the currently recommended total duration, might be useful for screening of older adults at higher mortality risk and for diversifying PA and SB targets in older populations whose adherence to current guidelines is low. Funding: National Institute on Aging; UK Medical Research Council; British Heart Foundation; Wellcome Trust; French National Research Agency; GlaxoSmithKline; Lausanne Faculty of Biology and Medicine; Swiss National Science Foundation.

Association of Type 2 Diabetes, According to the Number of Risk Factors Within Target Range, With Structural Brain Abnormalities, Cognitive Performance, and Risk of Dementia.

OBJECTIVE: Type 2 diabetes is associated with increased risks of cognitive dysfunction and brain abnormalities. The extent to which risk factor modification can mitigate these risks is unclear. We investigated the associations between incident dementia, cognitive performance, and brain abnormalities among individuals with type 2 diabetes, according to the number of risk factors on target, compared with control subjects without diabetes. RESEARCH DESIGN AND METHODS: Prospective data were from UK Biobank of 87,856 individuals (n = 10,663 diabetes, n = 77,193 control subjects; baseline 2006-2010), with dementia follow-up until February 2018. Individuals with diabetes were categorized according to the number of seven selected risk factors within the guideline-recommended target range (nonsmoking; guideline-recommended levels of glycated hemoglobin, blood pressure, BMI, albuminuria, physical activity, and diet). Outcomes were incident dementia, domain-specific cognitive performance, white matter hyperintensities, and total brain volume. RESULTS: After a mean follow-up of 9.0 years, 147 individuals (1.4%) with diabetes and 412 control subjects (0.5%) had incident dementia. Among individuals with diabetes, excess dementia risk decreased stepwise for a higher number of risk factors on target. Compared with control subjects (incidence rate per 1,000 person-years 0.62 [95% CI 0.56; 0.68]), individuals with diabetes who had five to seven risk factors on target had no significant excess dementia risk (absolute rate difference per 1,000 person-years 0.20 [-0.11; 0.52]; hazard ratio 1.32 [0.89; 1.95]). Similarly, differences in processing speed, executive function, and brain volumes were progressively smaller for a higher number of risk factors on target. These results were replicated in the Maastricht Study. CONCLUSIONS: Among individuals with diabetes, excess dementia risk, lower cognitive performance, and brain abnormalities decreased stepwise for a higher number of risk factors on target.