Dietary inflammatory index (DII®) and the risk of depression symptoms in adults.

BACKGROUND & AIMS: Findings from observational studies investigating the association between Dietary Inflammatory Index (DII®) scores and depression symptoms (DepS) are inconsistent. This study aims to assess the association between energy-adjusted DII (E-DII™) and DepS using the North West Adelaide Health Study (NWAHS) cohort as well as update a previous meta-analysis. METHODS: A total of 1743 (mean ± SD age: 56.6 ± 13.6 years, 51% female) study participants from NWAHS were included in the cross-sectional study and 859 (mean ± SD age: 58.4 ± 12.1 years, 52.6% female) in the longitudinal analyses. The Center for Epidemiological Studies Depression Scale (CES-D) was used for the measurement of DepS. E-DII scores were calculated from the dietary data collected using a validated food frequency questionnaire (FFQ). Data from two stages [Stage 3 (2008-10) and North West 15 (NW15) (2015)] were used. Log- and negative binomial regression were used to assess the association between quartiles of E-DII and DepS. A recent meta-analysis was updated by including 12 publications (six cross-sectional and six cohort studies) on the association between DII and DepS. RESULTS: In the cross-sectional analysis, a higher E-DII score (i.e., more pro-inflammatory diet) was associated with a 79% increase in odds of reporting DepS [ORQuartile4vs1: 1.79; 95% CI: 1.14-2.81; p = 0.01; p for trend (ptrend) = 0.03]. Males with higher E-DII had a more than two-fold higher odds of DepS (ORQuartile4vs1: 2.27; 95% CI: 1.02-5.06; p = 0.045; ptrend = 0.09). Females with higher E-DII had an 81% increase in odds of DepS (ORQuartile4vs1: 1.81; 95% CI: 1.01-3.26; p = 0.046; ptrend = 0.07). These associations were consistent in the longitudinal analysis. Comparing highest to lowest quintiles of E-DII, the updated meta-analysis showed that a pro-inflammatory diet is associated with a 45% increase in odds of having DepS (OR: 1.45; 95% CI: 1.20-1.74; p < 0.01) with higher odds in females (OR: 1.53; 95% CI: 1.16-2.01; p = 0.01) compared to their male counterparts (OR: 1.29; 95% CI: 0.98-1.69; p = 0.15). CONCLUSION: The data from the NWAHS and the updated meta-analysis of observational studies provide further evidence that a pro-inflammatory diet is positively associated with increased risk of DepS. These findings support the current recommendation on consuming a less inflammatory diet to improve DepS.

Association between dietary patterns and adult depression symptoms based on principal component analysis, reduced-rank regression and partial least-squares.

BACKGROUND & AIMS: There have been inconsistent findings on the association between dietary patterns and depressive symptoms (DepS). In addition, studies have used single analysis methods to identify dietary patterns. In the current study, we aimed to determine the association between dietary patterns, derived by principal component analysis (PCA), reduced-rank regressions (RRR) and partial least-squares (PLS), and DepS among adults using a cohort study in Australia. METHODS: We examined a total of 1743 study participants (≥24 years, 48.9% males) using cross-sectional and longitudinal data from the North West Adelaide Health Study (NWAHS). The Center for Epidemiological Studies-Depression (CES-D) scale was used to assess DepS and a score ≥16 was considered as having depression. Dietary data were collected using a food frequency questionnaire. Eicosapentaenoic acid (EPA)/Docosahexaenoic acid (DHA), folate, magnesium (Mg) and zinc (Zn) densities were chosen as the response variables for RRR and PLS analyses. Dietary patterns were identified by PCA, RRR and PLS. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated across quartiles (Q) using log-binomial logistic regression to assess the association between dietary patterns and DepS. Sensitivity analyses, including a longitudinal association between dietary patterns and DepS among 859 participants, were performed. Multiple imputation was performed to investigate the effect of missing data on the estimates. RESULTS: In this study, 16.9% (14.2% in men and 20.8% in women) of the participants had DepS. We retained two, four and four dietary patterns captured by PCA, RRR and PLS respectively. The 'prudent' pattern determined by PCA [ORQ4VsQ1 = 0.57; 95% CI: 0.35, 0.92] and PLS [ORQ4VsQ1 = 0.66; 95% CI: 0.43, 1.00] together with the 'typical Australian' pattern determined by RRR [ORQ4VsQ1 = 0.60; 95% CI: 0.40, 0.90] were inversely associated with DepS whereas the 'western' pattern derived by PCA [ORQ4VsQ1 = 2.04; 95% CI: 1.12, 3.68] and PLS [ORQ4VsQ1 = 1.62; 95% CI: 1.05, 2.50] was positively associated with DepS. In the longitudinal analysis, the 'prudent' pattern determined by PCA [ORQ4VsQ1 = 0.52; 95% CI: 0.25, 1.09] tended to be inversely associated with DepS whereas 'western' patterns determined by PCA [ORQ4VsQ1 = 3.47; 95% CI: 1.37, 8.78] and PLS [ORQ4VsQ1 = 2.47; 95% CI: 1.24, 4.91] were positively associated with DepS. We found that a dietary pattern characterized by high intakes of fruits, vegetables, medium fat dairy, nuts, legumes, and fish was inversely associated with DepS in this population-based study. Contrary to this, a dietary pattern characterized by high intakes of processed and red meat, fast foods (snacks and takeaway foods), soft drinks, white bread and high-fat dairy products were significantly associated with DepS. Multiple imputation and sensitivity analysis identified similar patterns of association between dietary pattern and DepS. CONCLUSIONS: The findings indicate that the 'western' pattern was consistently associated with an increased risk, and the 'prudent' pattern tended to be associated with a reduced risk of DepS. This suggests that dietary interventions may assist with the treatment of DepS. However, current evidence on the impact of diet on DepS should be supported using further longitudinal studies with extended follow up, larger sample sizes and repeated measures.

Urinary Iodine Excretion among Nepalese School Children in Terai Region.

OBJECTIVES: To assess the current iodine status among school children in Terai region of Nepal. METHODS: A cross sectional study was conducted in 2012 among the school children aged 6-12y in three Terai districts (Siraha, Saptari and Jhapa) of eastern Nepal. A total of 1105 casual urine samples were collected from children of different schools of above districts. Urinary iodine excretion was estimated using ammonium persulphate digestion method. RESULTS: The median urinary iodine excretion in school children was 226.33µg/L (234.16µg/L, 229.25µg/L and 210.67µg/L in Siraha, Saptari and Jhapa districts respectively). About 12.7% (n = 140) children were found to be iodine deficient and 34.2% (n = 378) children had excessive iodine nutrition. CONCLUSIONS: There was good improvement in iodine nutrition among children in Terai region, with a large part of population showing excessive iodine nutrition.

Urinary iodine excretion and thyroid function status in school age children of hilly and plain regions of Eastern Nepal.

BACKGROUND: Iodine deficiency is a major public health problem in many developing countries including Nepal. The present study was designed to investigate the urinary iodine excretion (UIE), thyroid function status and household salt iodine content (SIC) in school-aged children (SAC) and to establish the relationships between these factors. METHODS: A community-based cross sectional study was conducted in selected schools of two districts, Tehrathum and Morang, lying in the hill and plain region of eastern Nepal respectively. A total of 640 SAC, (Tehrathum n = 274 and Morang n = 366) aged 6-11 years, were assessed for UIE and household SIC. Among the 640 children, 155 consented to blood samples (Tehrathum n = 78 and Morang n = 77) to test for serum thyroglobulin (Tg), thyroid stimulating hormone (TSH), free triiodothyronine (fT3) and free thyroxine (fT4). UIE was measured by ammonium persulfate digestion method. SIC was measured by iodometric titration method and Tg, TSH, fT4 and fT3 were measured by immunoassay based kit method. RESULTS: In Tehrathum and Morang, 9.5 and 7.7% of SAC had UIE values of UIE <100 µg/L while 59.5 and 41% had iodine nutrition values of >299 µg/L, with median UIE of 345.65 and 270.36 µg/L respectively. The overall medians were as follows, Tg 14.29 µg/L, fT3 3.94 pmol/L, fT4 16.25 pmol/L and TSH 3.61 mIU/L. There was a negative correlation between UIE and Tg (r = -0.236, p = 0.003) and a positive correlation between UIE and SIC (r = 0.349, p < 0.0001). We found 19.5%, n = 15 and 16.7%, n = 13 subclinical hypothyroid cases in Morang and Tehrathum respectively. Iodometric titration showed only 6.4% (n = 41) of the samples had household SIC <15 ppm. Multivariate analysis revealed that use of packaged salt by SAC of Tehrathum district correlated with higher UIE values. CONCLUSIONS: Our focused data suggests that collaborative universal salt iodization (USI) programs are improving the health of children in the Tehrathum and Morang districts of Nepal. We also found that excessive iodine in a large portion of the study groups is a substantial concern and iodine intervention programs need to deal with both deficient and excessive iodine scenarios that can both be present simultaneously in study populations.

Anemia among school children in eastern Nepal.

Anemia is one of the most common public health problems in developing countries like Nepal. This study was done to find the prevalence of anemia among the children aged 4-13 years in eastern Nepal. A cross-sectional study was conducted in 2012 in four districts (Morang, Udayapur, Bhojpur and Ilam) of eastern Nepal to find the prevalence of anemia among the school children of eastern Nepal. Children aged 4-13 years were selected randomly from different schools of above districts and 618 venous blood samples were collected. Hemoglobin level was estimated by using cyanmethemoglobin method. The mean hemoglobin level was 12.2 ± 1.82 gm/dl. About 37.9% (n = 234) children were found anemic. Anemia prevalence was 42.4% (n = 78), 31.6% (n = 60), 45.3% (n = 48) and 34.8% (n = 48) among school children of Morang, Udayapur, Bhojpur and Ilam district, respectively. The study finds anemia as a significant health problem among the school children of eastern Nepal.

Iodine status after iodized salt supplementation in schoolchildren of eastern Nepal.

This study was designed to assess the urinary iodine concentrations of schoolchildren at baseline and after iodized salt supplementation in eastern region of Nepal. A cross sectional study was conducted from August 2009 to July 2011 among schoolchildren of three eastern districts of Nepal: Sunsari, Dhankuta, and Tehrathum. A sample of 828 school age children from the three districts was chosen for the study after obtaining written consent from their guardians. The schoolchildren treatment group (n=300) was provided with a supplement of iodized salt for six months. Urinary iodine concentration was estimated by ammonium persulfate digestion microplate method at baseline and after supplementation. Urinary iodine controls L1, L2 (Seronorm, Norway) were analyzed to obtain intra-assay CVs (L1 = 7.4%, L2 = 3.3%) and inter assay CVs (L1=23.5%, L2=11.26%). Median interquartile range urinary iodine concentration in the three districts: Sunsari, Dhankuta and Tehrathum at baseline versus intervention were 272.0 (131.5-473.0) microg/l versus 294.0 (265.0-304.0) microg/l (p=0.379), 247.0 (144.5-332.32) versus 361.0 (225.66-456.52) microg/l (p<0.001), and 349.5 (203.75-458.09) microg/l versus 268.76 (165.30-331.67) microg/l (p<0.001), respectively. This study indicated improved iodine status and increased median urinary iodine concentration after iodized salt supplementation. Regular monitoring of population urinary iodine concentration at national and regional levels should be performed to ensure that all individuals have optimal delivery of iodine nutrition.