Time Dependency of Cognitive Recovery with Cobalamin Replacement: Report or a Pilot Study

Abstract

There may be a time-limited window of opportunity for effective intervention in patients with cognitive dysfunction and low serum cobalamin.

Biochemical indicators of vitamin B 12 and folate insufficiency and cognitive decline

“…Serum vitamin B 12 concentrations have not been consistently associated with cognitive change in prospective analyses. [25][26][27][28][29] Few groups examined cognition in relation to measures that reflect preclinical or metabolic vitamin B 12 deficiency. In a cross-sectional UK survey of 1,000 individuals aged 75 years or older, cognitive impairment (defined as a MiniMental State Examination score Ͻ22) was more strongly associated with holotranscobalamin, a tissue transport protein for vitamin B 12 , homocysteine, and methylmalonic acid than with serum vitamin B 12 .…”

Practice parameter: Diagnosis of dementia (an evidence-based review)

“…115 Reports of improvement in cognitively impaired individuals with B 12 deficiency are equivocal. [116][117][118][119] Patients with B 12 deficiency have had slightly lower cognitive performance than nondeficient subjects, 120 but low vitamin B 12 levels in nondemented subjects carried no risk for the subsequent development of dementia. 121 The number of patients with dementia caused by B 12 deficiency states has been very small in prevalence studies 122 or meta-analyses of clinic samples.…”

Utilization of Cognitive Support in Episodic Free Recall as a Function of Apolipoprotein E and Vitamin B₁₂ or Folate Among Adults Aged 75 Years and Older.

“…For instance, among older adults vitamin B 12 and folate have been associated cross-sectionally with episodic memory (e.g., Hassing, Wahlin, Winblad, & Bäckman, 1999;Wahlin, Hill, Winblad, & Bäckman, 1996), spatial, and working memory ability, and verbal fluency (Lindeman, Romero, Koehler et al, 2000;Robins Wahlin, Wahlin, Winblad, & Bäckman, 2001), and also with spatial copying skills (Riggs, Spiro, Tucker, & Rush, 1996). Intervention studies (e.g., Martin, Francis, Protetch et al, 1992;Meadows, Kaplan, & Bromfield, 1994) have established a link with improved cognition in demented or cognitively impaired individuals, and low levels of those nutrients have also been associated with an increased risk of developing Alzheimer's disease (e.g., Wang, Wahlin, Basun et al, 2001). More broadly, there is evidence suggesting subclinical differences in those B vitamins may influence cognitive performance (see Calvaresi & Bryan, 2001).…”