Persistently high depressive symptoms are associated with increased stroke risk, according to a study published May 13 in Journal of the American Heart Association. This research included health information from 16,178 men and women age 50 or older who participated in the Health and Retirement Study between 1998 and 2010. Participants were interviewed every two years about depressive symptoms, history of stroke, and stroke risk factors, among other health measures. Stroke risk was elevated among participants with stable high (hazard ratio [HR], 2.14) or remitted (HR, 1.66) depressive symptoms, compared with participants with stable low or no depressive symptoms. Stable high depressive symptoms predicted stroke among all subgroups. Remitted depressive symptoms predicted increased stroke risk among women (HR, 1.86) and non-Hispanic white participants (HR, 1.66).
Chronic traumatic encephalopathy (CTE) is associated with altered and accelerated deposition of amyloid β, according to a study published online ahead of print May 6 in Acta Neuropathologica. Researchers studied a heterogeneous cohort of deceased athletes and military veterans with neuropathologically diagnosed CTE. The investigators found that amyloid β deposition was present in 52% of subjects with CTE. Moreover, amyloid β deposition in CTE occurred at an accelerated rate and with altered dynamics in CTE, compared with a normal aging population. In addition, amyloid β deposition was significantly associated with the presence of the APOE e4 allele, older age at symptom onset, and older age at death. Neuritic plaques were significantly associated with increased CTE tauopathy stage, comorbid Lewy body disease, and dementia.
Low-dose tetrahydrocannabinol (THC) does not significantly reduce dementia-related neuropsychiatric symptoms at 21 days, though it is well tolerated, according to a study published online ahead of print May 13 in Neurology. In a double-blind, placebo-controlled study, investigators randomly assigned patients with dementia and clinically relevant neuropsychiatric symptoms to receive 1.5 mg of THC or matched placebo three times daily for three weeks. Neuropsychiatric symptoms were reduced during both treatment conditions. The difference in reduction from baseline between THC and placebo was not significant. Changes in scores for agitation, quality of life, or activities of daily living also were not significantly different between treatment arms. The number of patients experiencing mild or moderate adverse events was similar in both groups. No effects on vital signs, weight, or episodic memory were observed.
Exposure to elevated levels of fine particulate matter is associated with smaller total cerebral brain volume, according to a study published in the May issue of Stroke. Researchers analyzed 943 adults in the Framingham Offspring Study who were relatively healthy and free of dementia and stroke. Investigators evaluated associations between exposure to fine particulate matter and total cerebral brain volume, hippocampal volume, white matter hyperintensity volume, and covert brain infarcts. A 2-μg/m3 increase in fine particulate matter was associated with –0.32% smaller total cerebral brain volume and 1.46 higher odds of covert brain infarcts. Living further away from a major roadway was associated with 0.10 greater log-transformed white matter hyperintensity volume for an interquartile range difference in distance, but no clear pattern of association was observed for extensive white matter.
Higher occupational attainment is associated with longer survival in autopsy-confirmed frontotemporal lobar degeneration, according to a study published online ahead of print April 22 in Neurology. Researchers performed a retrospective chart review of 83 demographically matched patients with autopsy-confirmed frontotemporal lobar degeneration or Alzheimer’s disease. They used linear regression to test for associations among occupational attainment, education, and patient survival. Median survival was 81 months among patients with frontotemporal lobar degeneration and 95 months among patients with Alzheimer’s disease. Years of education and occupational attainment were similar for both groups. Higher occupational attainment was associated with longer survival in frontotemporal lobar degeneration, but not in Alzheimer’s disease. The findings support the theory that education, occupation, and mental activity create cognitive reserve and protect against disease.
Obesity is a major risk factor for the incidence and chronicity of excessive daytime sleepiness (EDS), and weight loss is associated with its remission, according to a study published March 1 in Sleep. Investigators followed up 1,395 people from a random, general population sample of 1,741 participants in the Penn State Adult Cohort after 7.5 years. The incidence of EDS was 8.2%. Of people with EDS, 62% had remission. Significant interactions between depression and polysomnographic parameters on incident EDS showed that in depressed individuals, incident EDS was associated with sleep disturbances. In individuals without depression, incident EDS was associated with increased physiologic sleep propensity. Diabetes, allergy or asthma, anemia, and sleep complaints also predicted EDS. “EDS has huge implications for public health and policy,” stated the researchers.