[Serum folate and vitamin B12 in older people: results from the Chilean National Health Survey 2009-2010]

Micronutrient Deficiencies in Older Adults in Latin-America: A Narrative Review

BACKGROUND

The population in Latin America and Caribbean (LAC) has experienced a major demographic transition with increased numbers of older adults (OA). This change brings opportunities in the public health sector to implement health prevention interventions and delay the onset of geriatric syndromes. Micronutrients play an important role in the maintenance of biological function which contributes to longevity. Micronutrient deficiencies (MD) in OA increase the risk for onset of chronic comorbidities and geriatric syndromes.

AIM

To review and summarize the existing data on micronutrient status in OA in the LAC region and discuss the gaps and challenges in public health approaches to address deficiencies.

METHODS

Literature review in Medline for records describing nutritional biomarkers in older adults (≥ 60y) from community dwelling and population-based studies in LAC.

RESULTS

Few countries (including Chile, Ecuador, Costa Rica, Brazil, and Mexico) have documented one or more nutritional deficiencies for OA in national health surveys, however across the entire region, evidence of micronutrient levels is scarce. Some surveys have documented a high prevalence and large heterogeneity in the prevalence of vitamin D followed by B12 deficiency, being the 2 MDs most studied due their effects on cognition, frailty, and bone mineral density in the OA population. Other MD including C, E, A, copper, zinc, iron, and selenium have also been reported.

CONCLUSION

Information on the micronutrient status in OA from LAC is poorly documented. Research and capacity building initiatives in the region are crucial to develop tailored strategies that address the specific nutritional needs and challenges faced by the ageing population in Latin-America.

Components of Successful Staple Food Fortification Programs: Lessons From Latin America

BACKGROUND

There are few effectiveness evaluations of food fortification programs, and little is known about what makes programs successful.

OBJECTIVE

We examined 3 food fortification programs in Latin America to identify common features that might explain their success and to draw lessons for program design and implementation everywhere: The vitamin A fortification of sugar in Guatemala with impact on vitamin A status of the population, the fortification of a basket of foods with iron and other micronutrients in Costa Rica with impact on iron status and anemia in women and children, and the fortification of wheat flour with folic acid in Chile, which reduced the incidence of neural tube defects.

METHODS

We identified pertinent literature about these preselected programs and asked regional experts for any additional information. We also conducted structured interviews of key informants to provide historical and contextual information.

RESULTS

Institutional research capacity and champions of fortification are features of successful programs in Latin America. We also found that private/public partnerships (industry, government, academia, and civil society) might be key for sustainability. To achieve impact, program managers need to use fortification vehicles that are consumed by the nutritionally vulnerable and to add bioavailable fortificants at adequate content levels in order to fill dietary gaps and reduce micronutrient deficiencies. Adequate monitoring and quality control are essential.

CONCLUSIONS

For future programs, we recommend that the evaluation be specified up-front, including a baseline/end line and data collection along the program impact pathway to inform needed improvements and to strengthen causal inferences.

Vitamin B12 and folate levels in healthy Swiss senior citizens: a prospective study evaluating reference intervals and decision limits

BACKGROUND

The vitamin B12 and folate status in nonanaemic healthy older persons needs attention the more so as decrease in levels may be anticipated from reduced haematinic provision and/or impaired intestinal uptake.

METHODS

A total of 1143 subjectively healthy Swiss midlands participants (637 females and 506 males), ≥60 years of age were included in this study. Levels of vitamin B12, holotranscobalamin (holoTC), methylmalonic acid (MMA), homocysteine (Hcy), serum folate, red blood cell (RBC) folate were measured. Further, Fedosov's wellness score was determined. Associations of age, gender, and cystatin C/creatinine-based estimated kidney function, with the investigated parameters were assessed. Reference intervals were calculated. Further, ROC analysis was done to assess accuracy of the individual parameters in recognizing a deficient vitamin B12 status. Finally, decision limits for sensitive, specific and optimal recognition of vitamin B12 status with individual parameters were derived.

RESULTS

Three age groups: 60-69, 70-79 and ≥ 80 had median B12 (pmol/L) levels of 237, 228 and 231 respectively (p = 0.22), holoTC (pmol/L) of 52, 546 and 52 (p = 0.60) but Hcy (μmol/L) 12, 15 and 16 (p < 0.001), MMA (nmol/L) 207, 221 and 244 (p < 0.001). Hcy and MMA (both p < 0.001), but not holoTC (p = 0.12) and vitamin B12 (p = 0.44) were found to be affected by kidney function. In a linear regression model Fedosov's wellness score was independently associated with kidney function (p < 0.001) but not with age. Total serum folate and red blood cell (RBC) folate drift apart with increasing age: whereas the former decreases (p = 0.01) RBC folate remains in the same bandwidth across all age groups (p = 0.12) A common reference interval combining age and gender strata can be obtained for vitamin B12 and holoTC, whereas a more differentiated approach seems warranted for serum folate and RBC folate.

CONCLUSION

Whereas the vitamin B12 and holoTC levels remain steady after 60 years of age, we observed a significant increment in MMA levels accompanied by increments in Hcy; this is better explained by age-related reduced kidney function than by vitamin B12 insufficiency. Total serum folate levels but not RBC folate levels decreased with progressing age.

Serum folate, vitamin B12 and cognitive impairment in Chilean older adults

OBJECTIVE

To analyse the relationship between serum folate (SF), vitamin B12 and impaired cognitive function in the Chilean elderly.

DESIGN

We analysed the relationships between impaired cognitive function and age, SF (µg/l) and vitamin B12 (pg/ml) with Student's t test, as well as between impaired cognitive function and gender, educational level, residence area, diabetes and hypertension with the χ 2 test. Multiple logistic regressions with interactions were estimated to assess the impact of SF on impaired cognitive function according to these methods.

SETTING

Chile.

SUBJECTS

Older adults (>65 years, n 1051), drawn from representative households of a national prevalence study, assessed using the Modified Mini Mental Status Examination (MMMSE). Individuals with altered MMMSE scores (≤13 points) were sequentially assessed using the Pfeffer Functional Activities Questionnaire (PFAQ).

RESULTS

Multivariate models using the MMMSE demonstrated an increased risk of impaired cognitive function for seniors who had hypertension, diabetes and higher vitamin B12 levels. SF and its square (SF2) were statistically significant, indicating that this predictor of impaired cognitive function displays a U-shaped distribution. The interaction between SF and vitamin B12 was not statistically significant. Models using the MMMSE plus PFAQ suggested that urban residence decreased the risk of impaired cognitive function, whereas male gender, older age, vitamin B12 levels and hypertension increased this risk. The variables SF and SF2 and the SF × vitamin B12 interaction were statistically significant (P<0.05). The risk of impaired cognitive function depended on different combinations of SF and vitamin B12 levels. When SF was low, a one-unit increase in SF (1 µg/l) diminished the risk. When SF was elevated, a further increase in SF raised the risk, especially at low vitamin B12 levels.

CONCLUSIONS

The relationship between folate, vitamin B12 and impaired cognitive function warrants further study.

Vitamin B12 serostatus in Colombian children and adult women: results from a nationally representative survey

OBJECTIVE

Vitamin B12 deficiency is associated with many adverse health outcomes and is highly prevalent worldwide. The present study assesses the prevalence of vitamin B12 deficiency and marginal deficiency in Colombian children and women and examines the sociodemographic correlates of serum vitamin B12 concentrations in these groups.

DESIGN

Cross-sectional, nationally representative survey.

SETTING

Colombia.

SUBJECTS

Children <18 years old (n 7243), pregnant women (n 1781), and non-pregnant women 18-49 years old (n 499).

RESULTS

The overall prevalence of vitamin B12 deficiency (serum vitamin B12<148 pmol/l) and marginal deficiency (serum vitamin B12=148-221 pmol/l) was, respectively, 6.6 % (95 % CI 5.2%, 8.3%) and 22.5% (95% CI 21.1%, 23.9%). Pregnant women had the highest prevalence of deficiency (18.9 %; 95 % CI 16.6 %, 21.5 %) compared with non-pregnant adult women (18.5%; 95% CI 4.4%, 53.1%) and children (2.8 %; 95 % CI 2.3 % %, 3.3 %). In multivariable analyses among children, mean serum vitamin B12 was positively associated with female sex (12 pmol/l higher compared with males; P=0.004), secondary or higher education of the household head (12 pmol/l higher compared with primary or less; P=0.009) and food security (21 pmol/l higher compared with severe food insecurity; P=0.003). In multivariable analyses among pregnant women, mean serum vitamin B12 was positively associated with education of the household head and inversely associated with living in the National territories, Eastern or Pacific regions.

CONCLUSIONS

The prevalence of vitamin B12 deficiency and marginal deficiency in Colombian women and children is substantial. The burden falls largely on adult women, those with lowest education and those living in the poorest, most rural regions of the country.