Vitamin intake is associated with improved visuospatial and verbal semantic memory in middle-aged individuals

Life-Course Socioeconomic Position and Mild Cognitive Impairment in Midlife: Evidence from the 1958 British Birth Cohort

BACKGROUND

Dementia has been the leading cause of death in the UK since 2015. Increasing evidence supports an association between socioeconomic position (SEP) and dementia onset in later life. However, limited studies have examined how life-course SEP influences the development of mild cognitive impairment (MCI), an intermediate state potentially preceding dementia. Therefore, the present study aims to examine the relationship between life-course SEP and MCI amongst adults aged 50 years in Great Britain.

METHODS

We employed data from the National Child Development Study (NCDS), also known as the 1958 British Birth Cohort, to determine the associations between SEP and MCI in 6590 participants. We categorised life-course measures of SEP as stable high/low or moving upward/downward over the life course. We assessed MCI at age 50 using one standard deviation below the averaged combined scores from all cognitive tests available. We then used binary logistic regression to estimate the longitudinal associations between life-course SEP and MCI.

RESULTS

Relative to those of a high SEP across the life course, participants who moved upward, downward, or remained at a low SEP were significantly associated with 25% (95% CI 1.02-1.54, p = 0.035), 70% (95% CI 1.27-2.27, p < 0.001), and 85% (95% CI 1.50-2.29, p < 0.001), respectively, higher odds of MCI, independent of all selected covariates.

CONCLUSIONS

Lower life-course SEP was associated with significantly higher odds of MCI onset in middle life within the NCDS cohort. Public health policies targeting cognitive impairment should encompass a life-course approach to reduce socioeconomic inequalities.

Hyperhomocysteinemia is key for increased susceptibility to PND in aged mice

Background

Postoperative neurocognitive disorder (PND) is a severe postoperative complication with no effective therapy that affects up to 19–52% of senior patients. Age and surgery type have been identified as risk factors. However, what caused the increased risk in the elderly is poorly understood.

Methods

We utilized a PND model in aged mice undergoing experimental laparotomy with general anesthesia to evaluate the causal relationship between hyperhomocysteinemia and increased PND susceptibility. PND was assessed by Novel Object Tasks, Fear Conditioning Tests, and Barnes Maze Tests. Serum homocysteine (Hcy) as well as vitamin B12 and folate acid levels were tested before, immediately after surgery and from day 1 to day 29 after surgery by ELISA. The effectiveness of preventative strategy including diet supplementation of vitamin B12 + folic acid (Vit B12 + FA) and S‐adenosylmethionine (SAM) injection targeting hyperhomocysteinemia were also tested.

Results

PND in aged mice lasted for at least 2 weeks after experimental laparotomy, which was not observed in young adult mice. Serum Hcy results indicated a significant correlation between postoperative cognitive performance and perioperative Hcy level. Preoperative supplementation with VB12 and folic acid (FA) in the diet or S‐adenosylmethionine (SAM) injection reduced perioperative serum Hcy level and inhibited the development of PND in aged mice.

Conclusions

Serum homocysteine accumulation is a fundamental cause for increased susceptibility of PND in aged mice. Preoperative diet supplementation of VitB12 + FA can effectively reduce PND in aged mice, which may be a promising prophylaxis treatment in clinical settings.