Modest consumption of fish with high omega-3 fatty acids, such as tuna, is associated with a lower risk for cognitive decline and stroke. According to a report in the August 5 Neurology, 3,660 participants 65 and older underwent MRI; five years later, 2,313 participants had repeat scanning. Dietary intake was assessed using food frequency questionnaires. The risk for having one or more prevalent subclinical infarcts was lower among subjects who consumed fish three or more times per week, compared with less than once per month (relative risk, 0.74). Fish consumption was also associated with trends toward lower incidence of subclinical infarcts. “Additionally, tuna/other fish intake was associated with better white matter grade, but not with sulcal and ventricular grades, markers of brain atrophy,” noted the researchers. These associations were not found for fried fish consumption.
High and low thyrotropin levels are associated with an increased risk for Alzheimer’s disease in women, according to a study in the July 28 Archives of Internal Medicine. A total of 1,864 cognitively intact, clinically euthyroid participants were studied (mean age, 71; 59% were women). Alzheimer’s disease was diagnosed in 209 participants (142 women) during the mean follow-up of 12.7 years. Women at the lowest ( 2.1 mIU/L) tertiles of serum thyrotropin concentration had adjusted hazard ratios of 2.39 and 2.15, respectively, compared with those in the middle tertile, the investigators observed. This relationship continued after exclusion of those receiving thyroid supplementation and when analyses were limited to participants with serum thyrotropin levels of 0.1 to 10.0 mIU/L, but not when analyses were limited to patients with serum thyrotropin levels of 0.5 to 5.0 mIU/L. The association between thyrotropin level and Alzheimer’s disease was not found in men.
PET scans involving use of carbon 11–labeled Pittsburgh Compound B ([(11)C]PiB) may help to assess β-amyloid deposition in the brain among patients with Alzheimer’s disease. In a study in the August 11 online Archives of Neurology, 10 patients underwent intraventricular pressure monitoring with a frontal cortical biopsy for suspected normal-pressure hydrocephalus. “In patients with β-amyloid aggregates in the frontal cortical biopsy specimen, PET imaging revealed higher [(11)C]PiB uptake in the frontal, parietal, and lateral temporal cortices and in the striatum as compared with the patients without frontal β-amyloid deposits,” stated the researchers. They concluded that studies are needed to determine whether [(11)C]PiB could be used as a diagnostic tool, particularly for early Alzheimer’s disease.
Physical frailty in old age is associated with Alzheimer’s disease pathology, reported researchers in the August 12 Neurology. Brain autopsies from 165 deceased participants from the Rush Memory and Aging Project were studied, and information was collected on physical frailty based on grip strength, time to walk 8 feet, body composition, and fatigue. “The level of Alzheimer’s disease pathology was associated with frailty proximate to death, accounting for 4% of the variance of physical frailty,” reported the investigators. Frailty had no association with cerebral infarcts or Lewy body disease pathology. The findings were unchanged after the researchers controlled for time interval between last clinical evaluation to autopsy. Other potential confounders such as the presence of dementia, physical activity, parkinsonian signs, pulmonary function, and history of chronic diseases did not change this association.
Individuals with a spouse who currently smokes may have an increased risk for stroke, researchers reported in the September American Journal of Preventive Medicine. The investigators followed 16,225 stroke-free participants 50 and older for an average of 9.1 years. Proxy and self-report of first stroke totaled 1,130 events. Having a spouse who currently smoked was associated with an increased risk for first stroke among both never smokers and former smokers (hazard ratio, 1.42 and 1.72, respectively). Former smokers married to current smokers had a stroke risk similar to current smokers. “The health benefits of quitting smoking likely extend to both the individual smoker and his or her spouse,” the study authors concluded.
Women with the MTHFR 677TT genotype who have migraine with aura have an increased risk for cardiovascular disease and stroke, according to a study in the August 12 Neurology. Of the 25,001 women studied, 4,577 (18.3%) reported a history of migraine; 39.5% of the 3,226 women with active migraine indicated aura. During a mean of 11.9 years of follow-up, 625 cardiovascular disease events occurred. The TT genotype was associated with lower risk for migraine with aura (relative risk [RR], 0.79) and did not increase the risk for cardiovascular disease. However, migraine with aura doubled the risk for cardiovascular disease (RR, 2.06). The presence of migraine with aura and the TT genotype greatly increased that risk (RR, 3.66) and also increased the risk for ischemic stroke (RR, 4.19).

—Marguerite Spellman

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