Comparison of two modes of vitamin B12supplementation on neuroconduction and cognitive function among older people living in Santiago, Chile: A cluster randomized controlled trial. a study protocol [ISRCTN 02694183]

Abstract

Background: Older people have a high risk of vitamin B 12deficiency; this can lead to varying degrees of cognitive and neurological impairment. CBL deficiency may present as macrocytic anemia, subacute combined degeneration of the spinal cord, or as neuropathy, but is often asymptomatic in older people. Less is known about subclinical vitamin B12 deficiency and concurrent neuroconduction and cognitive impairment. A Programme of Complementary Feeding for the Older Population (PACAM) in Chile delivers 2 complementary fortified foods that provide approximately 1.4 μg/day of vitamin B12 (2.4 μg/day elderly RDA). The aim of the present study is to assess whether supplementation with vitamin B12 will improve neuroconduction and cognitive function in older people who have biochemical evidence of vitamin B12 insufficiency in the absence of clinical deficiency. Methods. We designed a cluster double-blind placebo-controlled trial involving community dwelling people aged 70-79 living in Santiago,