[Urinary and breast milk iodine concentrations in lactating mothers and its association with certain demographic characteristics in an area with iodine sufficiency]

Introduction: lactating mothers and breastfed infants are most vulnerable to iodine deficiency. The aim of this study was to assess the iodine status of lactating mothers and its association with certain demographic characteristics in an area of iodine sufficiency

Materials and Methods: in this cross-sectional study, 264 lactating mothers, 3-5 days postpartum were randomly selected from health care centers. Breast milk, urine, and salt samples were collected from each mother. Demographic factors including age, education, occupation, date of last pregnancy, parity, gravidity, type of delivery and use of iodine containing supplement during pregnancy were assessed

Results: a total of 254 lactating mothers, aged 28.2 +/- 4.9 years completed this study. Median [interquartile range [IQR]] maternal urinary iodine concentration [UIC] and breast milk iodine concentration [BMIC] was 82 [42-146] and 241 [167-337] [micro]g/L, respectively. Significant correlations were observed between maternal UIC and BMIC [r =0.177, P=0.007]. In multiple linear regression, maternal UIC value was associated with occupation [P=0.010] and parity [P=0.014]; a significant association was observed between BMIC and occupation [P=0.039] and the iodine content of salt [P=0.043]

Conclusion: the present findings indicate that despite lactating mothers being mildly iodine deficient, as defined by median UIC, the iodine levels of breast milk were within an optimal range. In an area with iodine sufficiency, parity, occupation and iodine content of salt are major determinants of iodine status among lactating mothers

[Using a scientific map to compare scientific publications on poly cystic ovary syndrome in Iran, Middle East and other countries]

Introduction: Polycystic ovary syndrome [PCOS], one of the most common gynecological diseases, has been the subject of many scientific studies. Scientific map is one way to obtain useful information about a particular research field status. We aimed to compare the quantity of scientific publications on PCOS in Iran to those of the Middle East and other countries

Materials and Methods: In this scientometric study, the samples included all medical scientific publications about PCOS, indexed in the Web of Knowledge from 2000 to 2016. Bibexcel software was used for calculating subject category co-citation, analyzing social networks and two Pajek and VOS viewer software were used for creating maps

Results: Iran ranked eighth among the top ten leading countries in the production of scientific articles in the field of PCOS. Of overall 6598 scientific publications related to PCOS worldwide, 209 articles were authored by Iranian researchers. In other words, 4.3 % of scientific productions in this field are from our country. In this list, America ranks first with 1670 [34.3%] articles, followed by China with 567 [11.7%], and Turkey with 564 [11.6%] publications ranking second and third. Of the fifteen Iranian research pioneers, each one had at least seven papers in the field of PCOS

Conclusion: Iran ranks among the top ten countries with regard to scientific publications worldwide. Considering the lack of knowledge in certain aspects of PCOS identifying more pioneers in this research field will help highlighting new research topics for future researches in this field

[Application of quantile regression model in assessment of urine iodine related factors in Tehran population]

Quantile regression can be applied to model skewed variables, especially, when the objective is to model the tails of a response variable with highly skewed distribution. The aim of this study is to apply quantile regression to analyze urine iodine data and related factors in a Tehranian population. Data was collected in a cross-sectional study, in which 639 subjects, aged 19 years and over, were enrolled through randomized cluster sampling in Tehran between 2008-9. Due to the high skewness of 24 hr urinary iodine concentrations [UIC24] and to evaluate its extreme points, two linear quantile regression models were fitted. In model I, UIC24 was regressed on iodine content of salt and daily salt intake. These variables were replaced by iodine intake in model II, both models were adjusted by age. Model coefficients were estimated using the linear programming method and simplex algorithm. Significancy of the variables were evaluated by the bootstrap method. The Akaike information criterion [AIC] was used to assess the fitting of the models. All analyses were performed using R software version 2.12.2. Model I showed an increase in coefficients of iodine content of salt, daily salt intake, but a decrease in age coefficient in the length of the urinary iodine concentration percentiles. Model II showed similar results, but better fit [smaller AIC] in percentiles lower than median. Compared to ordinary regression, quantile regression models showed better fit, and a more complete picture and are recommended for modeling all parts of UIC24

[Evaluation of urinary iodine concentration and iodine content of households salt in south of Tehran]

Iodized salt is the main dietary source of iodine in Iran. Previous studies have shown sustainable elimination of iodine deficiency disorders in Iran. The aim of this study was to evaluate urinary iodine concentration and the iodine content of households salt in the south of Tehran in 2009. This cross-sectional study, 91 households were enrolled through randomized cluster sampling. A total of 147 adult subjects [62 males, 85 females], aged 18 and over, were selected from households to provide 24 hr urine samples. Urinary iodine and creatinine concentrations were measured by using the digestion method and autoanalizer assay, respectively. Daily salt consumption was estimated and household salt iodine content was measured by titration. Mean +/- SD iodine concentration of household salt was12.7 +/- 14.7 ppm, and 64.8% of household salts contained < 10 ppm iodine. The median of Urinary Iodine Concentration [UIC] was 48.0 micro g/l. There was no statistically significant difference in UIC, between men and women. The median daily salt consumption was 9.1 g. According to WHO/ICCIDD/UNICEF classification, 17.0, 30.6, 45.6 and 6.8 percent of participants had UICs >100, 50-99, 20-49 and <20 micro g/l, respectively. Iodine contents of household salts were not adequate in the south of Tehran, indicating Tehranians in this region, previously iodine sufficient, now suffer from moderate iodine deficiency. These findings show necessity of more detailed surveys for iodine nutrition improvement and emphasize the importance of attention being paid to the risk of iodine deficiency recurrence in Iran