Homocysteine, rather than age of onset, is a better predictor for cognitive function in older adults with bipolar disorder

Abstract

Objectives The association between older‐age bipolar disorder and cognitive impairments may be mediated by vascular burden. The aim of the study was to examine the difference of cognitive function between older people with late‐onset bipolar disorder (LOBD) and early‐onset bipolar disorder (EOBD) by considering rigorous vascular risk burden evaluation, comprehensive cognitive tests, and relevant biochemistry data. Methods We recruited 95 outpatients aged over 55 with a DSM‐IV‐TR diagnosis of bipolar I disorder. Fifty had LOBD, defined by age of onset after 40. Cognitive function was evaluated through a battery of tests assessing verbal memory, attention/speed, visuospatial function, verbal fluency, and cognitive flexibility. Vascular risk assessments included individual disorders, 10‐year Framingham cardiovascular risk scores, and serum levels of homocysteine, vitamin B12, folate, and triiodothyronine. Results No differences were observed between LOBD and EOBD on any cognitive test after adjusting for potential confounders. In addition to age and educational years, multiple linear regression analyses indicated significantly negative associations between serum homocysteine levels and cognitive performances in attention, psychomotor speed, verbal memory, and executive function. Conclusions Among older people with bipolar disorder, LOBD is not associated with more cognitive dysfunction in this study. However, higher serum homocysteine levels were significantly associated with worse cognitive performance in this particular group. Clinicians therefore have to pay attention to the cognitive function in older bipolar patients with higher levels of homocysteine.

Association Between Plasma Homocysteine Levels and Cognitive Deficits in Han Chinese Patients with Schizophrenia across Age Groups

“…Moreover, a previous study showed that plasma Hcy levels increased signi cantly with age in a Northeast Chinese population 10 . In addition, Chen PH et al 6 showed a signi cant association between higher plasma Hcy concentration and worse cognitive performance in patients with late-onset bipolar disorder. Taken together, age may play an important role in determining Hcy levels in both the healthy population and patients with psychiatric disorders.…”

“…Biomarkers, such as homocysteine (Hcy), kynurenic acid, C-reactive protein, and triiodothyronine, have been shown to be potential risk factors for schizophrenia [2][3][4][5] . Hcy interacts with NMDA receptors, induces apoptosis, triggers oxidative stress, injures mitochondrial function and leads to vascular damage, which played an essantial role in the occurrence and development of schizophrenia 6 . Elevated plasma Hcy levels might also contribute to cognitive de cits that are common in patients with schizophrenia, even when the analyses are corrected for the relevant covariates 7 .…”

Association between plasma homocysteine levels and cognitive deficits in Han Chinese patients with schizophrenia across age groups

“…Biomarkers, such as homocysteine (Hcy), kynurenic acid, C-reactive protein, and triiodothyronine, have been shown to be potential risk factors for schizophrenia 2 – 5 . Hcy interacts with NMDA receptors, induces apoptosis, triggers oxidative stress, injures mitochondrial function and leads to vascular damage, which played an essential role in the occurrence and development of schizophrenia 6 . Elevated plasma Hcy levels might also contribute to cognitive deficits that are common in patients with schizophrenia, even when the analyses are corrected for the relevant covariates 7 .…”

Sex differences in the prevalence and clinical correlates of hyperhomocysteinemia in patients with bipolar disorder

“…Therefore, they speculated that functional differentiation may play an important role in the development of HHcy in BD patients (Levine et al, ). A recent study found that Hcy was a better predictor for cognitive function in elderly BD patients (Chen et al, ), which may provide the support for Levine's point of view.…”

“…Therefore, they speculated that functional differentiation may play an important role in the development of HHcy in BD patients (Levine et al, 2005). A recent study found that Hcy was a better predictor for cognitive function in elderly BD patients (Chen et al, 2019), which may provide the support other studies have found that valproic acid use was significantly associated with elevated Hcy level only in children with epilepsy (Dinç & Schulte, 2018). The results of adult patients with epilepsy were contradictory (Dinç & Schulte, 2018).…”