Type 2 Diabetes and Biomarkers of Brain Structure, Perfusion, Metabolism, and Function in Late Mid-Life: A Multimodal Discordant Twin Study.

BACKGROUND: Type 2 diabetes (T2D) is associated with an increased risk of dementia and early features may become evident even in mid-life. Characterizing these early features comprehensively requires multiple measurement modalities and careful selection of participants with and without T2D. OBJECTIVE: We conducted a cross-sectional multimodal imaging study of T2D-discordant twins in late mid-life to provide insights into underlying mechanisms. METHODS: Measurements included computerized cognitive battery, brain MRI (including arterial spin labelling, diffusion tensor, resting state functional), fluorodeoxyglucose (FDG)-PET, and retinal optical coherence tomography. RESULTS: There were 23 pairs, mean age 63.7 (±6.1) years. In global analyses, T2D was associated with poorer attention (ß= -0.45, p <0.001) and with reduced FDG uptake (ß= -5.04, p = 0.02), but not with cortical thickness (p = 0.71), total brain volume (p = 0.51), fractional anisotropy (p = 0.15), mean diffusivity (p = 0.34), or resting state activity (p = 0.4). Higher FDG uptake was associated with better attention (ß= 3.19, p = 0.01) but not with other cognitive domains. In regional analyses, T2D was associated with lower accumbens volume (ß= -44, p = 0.0004) which was in turn associated with poorer attention. CONCLUSION: T2D-related brain dysfunction in mid-life manifests as attentional loss accompanied by evidence of subtle neurodegeneration and global reduction in cerebral metabolism, in the absence of overt cerebrovascular disease.

Hypertension in the older person: is age just a number?

Older patients with hypertension are at a higher risk of cardiovascular events compared to younger adults but are also more vulnerable to the adverse effects of blood pressure (BP) lowering. Frailty is an important predictor of vulnerability to such adverse events, and age alone may not best reflect underlying risk. Therefore, an individualised approach to management of hypertension in the older person is required. Such an approach requires knowledge of frailty, the physiology of hypertension and ageing and a contextual understanding of best evidence. Management needs to be holistic and take account of the older person's care needs, wishes and priorities. This review describes physiological considerations and current guidelines and best practices regarding BP lowering in older people and highlights areas with paucity of evidence. A proposed and testable approach to managing hypertension in the older person (≥70 years) is discussed.

Is Blood Pressure Lowering in the Very Elderly With Previous Stroke Associated With a Higher Risk of Adverse Events?

Background We investigated whether blood pressure lowering for secondary prevention is associated with a reduction in recurrent stroke risk and/or a higher risk of adverse events in very elderly compared with younger trial participants. Methods and Results This is a random effects meta-analysis of randomized controlled trials of blood pressure lowering for secondary stroke prevention to evaluate age-stratified (<80, ≥80 years) risk of adverse events. Ovid-MEDLINE was searched for trials between 1970 and 2020. Summary-level data were acquired including outcomes of stroke, cardiovascular events, mortality, and adverse events. Seven trials were included comprising 38 596 participants, of whom 2336 (6.1%) were aged ≥80 years. There was an overall reduction in stroke risk in the intervention group compared with controls (risk ratio [RR], 0.90 [95% CI, 0.80, 0.98], I2=49%), and the magnitude of risk reduction did not differ by age subgroup (<80, ≥80 years). There was no increase in the risk of hypotensive symptoms in the intervention group for patients aged <80 years (RR, 1.19 [95% CI, 0.99], 1.44, I2=0%), but there was an increased risk in those ≥80 years (RR, 2.17 [95% CI, 1.22], 3.86, I2=0%). No increase was observed in the risk of falls, syncope, study withdrawal, or falls in either age subgroup. Conclusions Very elderly people in secondary prevention trials of blood pressure lowering have an increased risk of hypotensive symptoms, but with no statistical increase in the risk of falls, syncope, or mortality. However, evidence is lacking for frail elderly with multiple comorbidities who may be more vulnerable to adverse effects of blood pressure lowering.