RESUMEN
Objectives: Prenatal calcium supplementation is recommended by the WHO to decrease the risk of preeclampsia when dietary calcium intake is low; yet, this recommendation has not been successfully implemented to date. We aimed to evaluate the preference and acceptability of 4 different options for delivering prenatal calcium supplements (conventional tablets, chewable tablets, unflavoured powder, and flavoured powder) at the WHO recommended dose among pregnant women in urban Bangladesh. Methods: In a modified discrete-choice experiment, pregnant women (n = 132) completed a 4-day ‘run-in period' in which each delivery vehicle was sampled once, followed by a 21-day ‘selection period' during which participants freely selected a single vehicle per day. Preference was objectively based on the probability of selection of each vehicle; acceptability was assessed using questionnaires. Results: Conventional tablets had the highest probability of selection (62%); the probability of selection of chewable tablets (19%), flavored powder (12%), and unflavored powder (5%) were all significantly lower than for conventional tablets (P < 0.001). Palatability and product characteristics of the conventional tablets were more acceptable based on subjective report than for the other delivery vehicles. Conclusions: Our methodological approach used both objective and subjective measures to consistently identify the most preferred and accepted prenatal calcium delivery vehicle. Observation of participants' actual supplement use, in addition to expressed perceptions of acceptability, demonstrated that a conventional tablet is likely to be the most successful calcium delivery vehicle for future use in field studies and scale-up of the WHO recommendation for prenatal calcium supplementation in Bangladesh.
RESUMEN
Vitamin D deficiency is a global public-health concern, even in tropical regions where the risk of deficiency was previously assumed to be low due to cutaneous vitamin D synthesis stimulated by exposure to sun. Poor vitamin D status, indicated by low serum concentrations of 25-hydroxyvitamin D [25(OH)D], has been observed in South Asian populations. However, limited information is available on the vitamin D status of young infants in this region. Therefore, to gain preliminary insights into the vitamin D status of infants in rural Bangladesh, 25(OH)D was assessed in a group of community-sampled control participants in a pneumonia case-control study in rural Sylhet, Bangladesh (25°N) during the winter dry season (January-February). Among 29 infants aged 1-6 months, the mean 25(OH)D was 36.7 nmol/L [95% confidence interval (CI) 30.2-43.2]. The proportion of infants with vitamin D deficiency defined by 25(OH)D <25 nmol/L was 28% (95% CI 10-45), 59% (95% CI 40-78) had 25(OH)D<40 nmol/L, and all were below 80 nmol/L. From one to six months, there was a positive correlation between age and 25(OH)D (Spearman=0.65; p=0.0001). Within a larger group of 74 infants and toddlers aged 1-17 months (cases and controls recruited for the pneumonia study), young age was the only significant risk factor for vitamin D deficiency [25(OH)D <25 nmol/L]. Since conservative maternal clothing practices (i.e. veiling) and low frequency of intake of foods from animal source (other than fish) were common among the mothers of the participants, determinants of low maternal-infant 25(OH)D in Bangladesh deserve more detailed consideration in future studies. In conclusion, the vitamin D status in young infants in rural Sylhet, Bangladesh, was poorer than might be expected based on geographic considerations. The causes and consequences of low 25(OH)D in infancy and early childhood in this setting remain to be established.