Association of vitamin D and vitamin B12 with cognitive impairment in elderly aged 80 years or older: a cross-sectional study.

BACKGROUND: The present study aimed to assess the association of vitamin D and vitamin B12 with cognitive impairment in elderly people. METHODS: The data were obtained from a cross-sectional study that included individuals aged 80 years or older living in the urban and rural areas of the cities of Siderópolis and Treviso in the state of Santa Catarina, Brazil. In total, 165 elderly people were included in the analysis. The outcome of cognitive decline was assessed by the Mini-Mental State Examination. Vitamin D and vitamin B12 levels were measured from blood samples. The socio-demographic, anthropometric and health variables used in the analysis were collected from a questionnaire. Crude and adjusted analyses of the relationship between vitamins D and B12 and cognitive decline were performed using a Poisson regression model. RESULTS: The prevalence of cognitive decline was 35.2%. In the adjusted model, individuals who had vitamin D levels >19 ng mL-1 showed a lower prevalence of cognitive decline (prevalence ratio = 0.59; 95% confidence interval = 0.39-0.87). Those participants who had vitamin B12 levels of ≥496 pg mL-1 had a higher prevalence of cognitive decline (prevalence ratio = 1.90; 95% confidence interval = 1.08-3.36). CONCLUSIONS: The present study showed that individuals aged ≥80 years who had vitamin D levels of ≤18 ng mL-1 had a higher prevalence of cognitive decline even after adjustment for potential confounders. In addition, the study demonstrated that vitamin B12 levels of ≥496 pg mL-1 in this population were also a risk factor for cognitive decline. A cross-sectional analysis does not enable the inference of a cause-effect relationship and additional studies are needed to understand these relationships.

The effect of vitamin D on cognitive functions in young female patients: a prospective controlled study using the Montreal Cognitive Assessment.

AIM: Our aim was to determine whether there is a relationship between vitamin D [25(OH)D] and cognitive functioning in women with low 25(OH)D levels. METHODS: Ninety female patients, 25-45 years of age, who attended our outpatient clinic and had 25(OH)D levels < 30 ng/mL, were included. The Montreal Cognitive Assessment (MoCA) scale was used to determine cognitive functioning; the scale is divided into seven subgroups. Patients were divided into three subgroups according to their 25(OH)D levels. After a three-month period of 25(OH) D replacement, the patients underwent a re-evaluation using the MoCA scale. RESULTS: The total MoCA score before treatment was significantly different from the score after treatment (p < 0.05). Language and delayed recall functions were significantly different before and after treatment (p < 0.05). CONCLUSION: Vitamin D levels were related to cognitive functioning in our study group.

The effect of vitamin D on cognitive functions in young female patients: a prospective controlled study using the Montreal Cognitive Assessment / O efeito da vitamina D nas funções cognitivas em pacientes jovens do sexo feminino: um estudo prospectivo controlado usando a avaliação cognitiva de Montreal

ABSTRACT Aim: Our aim was to determine whether there is a relationship between vitamin D [25(OH)D] and cognitive functioning in women with low 25(OH)D levels. Methods: Ninety female patients, 25-45 years of age, who attended our outpatient clinic and had 25(OH)D levels < 30 ng/mL, were included. The Montreal Cognitive Assessment (MoCA) scale was used to determine cognitive functioning; the scale is divided into seven subgroups. Patients were divided into three subgroups according to their 25(OH)D levels. After a three-month period of 25(OH) D replacement, the patients underwent a re-evaluation using the MoCA scale. Results: The total MoCA score before treatment was significantly different from the score after treatment (p < 0.05). Language and delayed recall functions were significantly different before and after treatment (p < 0.05). Conclusion: Vitamin D levels were related to cognitive functioning in our study group.

RESUMO Objetivo: Nosso objetivo foi determinar se existe uma relação entre a vitamina D [25(OH)D] e o funcionamento cognitivo em mulheres com baixos níveis de 25(OH)D. Métodos: Noventa pacientes do sexo feminino (25-45 anos de idade) que se apresentaram ao nosso ambulatório e tinham níveis de 25(OH)D <30 ng/mL foram incluídas. A escala de avaliação cognitiva de Montreal (MoCA) foi usada para determinar o funcionamento cognitivo; a escala é dividida em sete subgrupos. As pacientes foram divididas em três subgrupos de acordo com seus níveis de 25(OH)D. Após um período de três meses de reposição de 25(OH)D, as pacientes foram submetidas a uma reavaliação de acordo com a escala MoCA. Resultados: O escore total da MoCA antes do tratamento foi significativamente diferente do escore após o tratamento (p <0,05). As funções de idioma e recordação atrasada foram mais significativamente diferentes entre antes e depois do tratamento (p <0,05). Conclusão: O nível de vitamina D foi relacionado ao funcionamento cognitivo em nosso grupo de estudo.

Vitamin D and alcohol: A review of the current literature.

Vitamin D is associated with bone mineral density, and its deficiency is a global health problem. In psychiatry, low vitamin D levels have been associated with schizophrenia, depression, psychotic symptoms, and, more recently, alcohol use disorders. Alcohol use disorders are among the most prevalent mental disorders worldwide. Therefore, our aim was to evaluate the association between alcohol use and vitamin D serum levels. The PubMed, SCIELO, and Lilacs databases were searched for this systematic review. We assessed all articles published from 1976 to December 2015, and we examined the associated reference lists to retrieve articles that appeared to fulfill our criteria. Of 932 articles, 49 met our inclusion criteria. The majority of the papers (71.4%) were cross-sectional studies. Alcohol intake was found to be positively associated with vitamin D status in 15 articles and negatively associated with vitamin D in 18 articles; no association was found in 16 articles. Heterogeneous results were found in our review, with a similar number of papers indicating a positive association, a negative association or the absence of any association between alcohol use and vitamin D levels. Nevertheless, it is important to note that the studies in which a positive association was found were more recent papers that involved considerably larger sample sizes than those in other studies. The older studies compared vitamin D levels in alcoholic and non-alcoholic patients, in contrast to more recent studies, which focused on more specific populations. In addition, most of the selected papers were from high latitude countries, where exposure to sunlight tends to be lower than in tropical countries. The data concerning vitamin D levels in patients with alcohol use disorders remain controversial. Additional research using a standardized methodology is necessary to demonstrate the real impact of alcohol consumption on vitamin D serum levels as well as on the health status of alcohol users.