RESUMEN
We studied neuroinflammation in individuals with late-life depression, as a risk factor for dementia, using [11C]PK11195 positron emission tomography (PET). Five older participants with major depression and 13 controls underwent PET and multimodal 3T magnetic resonance imaging (MRI), with blood taken to measure C-reactive protein (CRP). We found significantly higher CRP levels in those with late-life depression and raised [11C]PK11195 binding compared with controls in brain regions associated with depression, including subgenual anterior cingulate cortex, and significant hippocampal subfield atrophy in cornu ammonis 1 and subiculum. Our findings suggest neuroinflammation requires further investigation in late-life depression, both as a possible aetiological factor and a potential therapeutic target.
Asunto(s)
Proteína C-Reactiva/análisis , Corteza Cerebral , Trastorno Depresivo Mayor , Inflamación , Receptores de GABA/metabolismo , Anciano , Anciano de 80 o más Años , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/inmunología , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Trastorno Depresivo Mayor/sangre , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/inmunología , Trastorno Depresivo Mayor/patología , Femenino , Hipocampo/diagnóstico por imagen , Hipocampo/inmunología , Hipocampo/metabolismo , Hipocampo/patología , Humanos , Inflamación/diagnóstico por imagen , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/patología , Imagen por Resonancia Magnética , Masculino , Imagen Multimodal , Tomografía de Emisión de PositronesRESUMEN
OBJECTIVES: Subjective memory complaints (SMC) are common. We aimed to characterize the relationship between psychiatric illness and white matter disease to SMC in a sample of healthy older people. MEASUREMENTS: Cognitively normal subjects between 55 and 90 years had age-adjusted and education-adjusted Consortium to Establish a Registry for Alzheimer's disease (CERAD) scores ≤1.5 SD from standard mean. ApoE genotyping was performed using polymerase chain reaction. Sixty subjects (30 SMC, 30 controls) underwent 3T MRI, which was rated by two raters blinded to the diagnosis, for periventricular (PVH) and deep white matter hyperintensities (DWMH) using the Fazekas scale. Subjective memory was assessed by asking the participant, Do you feel like your memory or thinking is becoming worse? RESULTS: Two hundred and fifteen volunteers were assessed. Ninety-six were cognitively normal (mean age 62.5 years). SMC were reported by 52/96 subjects (54%). These were compared with subjects who denied SMC. Participants with a history of depression or anxiety were more likely to have SMC (p = 0.02). The frequency distribution of ApoE4 allele and CERAD scores were similar. White matter load was similar (p ≤ 0.47), with a high prevalence of PVH and DWMH seen (100% and 88% of scans, respectively). CONCLUSION: Both SMC and white matter disease were common. SMC were associated with a history of depression or anxiety but not with white matter disease. Evaluation for a history of depression and anxiety in people with SMC is supported by these findings.