Brain Inflammation May Result From Psychologic Stress in Persons Living With HIV

People living with HIV have known greater rates of stroke, but the reason for that risk was the focus of an abstract presented last week at IAS 2021, this year's virtual annual meeting of the International AIDS Society, which took place July 18 to 21.

“Even after accounting for traditional risk factors and HIV-related variables, ischemic stroke remains up to 65% higher for persons living with HIV,” the investigators wrote.

Stress, as it relates to neural inflammatory pathways, may be the reason why, they believe, so they investigated “the relationship between stress, metabolic activity in stress-related brain regions, and arterial inflammation on 18F-fluorodeoxyglucose (FDG)-PET [positron emission tomography], the latter being predictive of ischemic stroke and other CVD events.”

Overall, the authors analyses (Voxelwise group comparisons and linear regression analyses) showed the following associations:

• Perceived stress, chronic stress, posttraumatic stress, and depression were shown to have a significant negative correlation with metabolic activity in the amygdala and hippocampal brain regions.
• Stress and amygdalar network activity did not have a significant relationship.
• Perceived stress and chronic stress had a positive correlation with carotid inflammation.
• Metabolic activity had a significant association with aortic inflammation in the dorsolateral and medial prefrontal brain regions.

In addition, the following metabolic activity ranges were seen in the regions—entorhinal cortex, amygdala, hippocampi, carotid—of the brain evaluated:

• Perceived stress: from 0.122 (95% CI, 0.014-0.230; P = .029) in the carotid region to –0.030 (95% CI, –0.057 to 0.003; P = .031) in the entorhinal cortex
• Chronic stress: from 0.115 (95% CI, 0.011-0.219; P = .032) in the carotid region to –0.024 (95% CI, – 0.003 to –0.047; P = .026) in the amygdala
• Posttraumatic stress: from –0.027 (95% CI, –0.005 to –0.048; P = .014) in the amygdala to –0.031 (95% CI, –0.058 to –0.004; P = .025) in the entorhinal cortex
• Depression: from –0.031 (95% CI, –0.011 to –0.052 (P = .003) in the hippocampi to –0.032 (95% CI, –0.058 to –0.005 (P = .020) in the entorhinal cortex

The Perceived Stress Scale, Chronic Burden Scale, PTSD Checklist-Civilian, HIV Stigma Scale, and Patient Health Questionnaire-9 were used to gauge stress, as was total adverse childhood experiences.

Among their study cohort of 32 persons living with an undetectable HIV viral load (≤ 40 copies/mL) who underwent FDG-PET and clinical and neuropsychiatric testing, the mean (SD) age was 60 (7) years, and 97% were assigned male sex at birth. Most (78%) were non-Hispanic White, and 88% had been living with HIV for a median 29 years. Their top 5 cardiovascular risk factors were hyperlipidemia (78%), aspirin/statin use (66%), any current alcohol use (59%), current/prior cocaine use (59%), and hypertension (53%). There were also 30 age- and sex-matched controls who were not living with HIV.

“These findings warrant further investigation into the mechanisms by which stress and brain metabolic activity in stress-responsive regions are associated with greater arterial inflammation in people living with HIV,” the authors concluded.

Reference

Chow FC, Strom A, Abohashem S, et al. Psychological stress is associated with carotid inflammation in persons with treated HIV infection. Presented at: IAS 2021; July 18-21, 2021. Accessed July 23, 2021. https://conference.ias2021.org/media-391-psychological-stress-is-associated-with-carotid-inflammation-in-persons-with-treated-hiv-i