Construction and validation of the area level deprivation index for health research: A methodological study based on Nepal Demographic and Health Survey.

Area-level factors may partly explain the heterogeneity in risk factors and disease distribution. Yet, there are a limited number of studies that focus on the development and validation of the area level construct and are primarily from high-income countries. The main objective of the study is to provide a methodological approach to construct and validate the area level construct, the Area Level Deprivation Index in low resource setting. A total of 14652 individuals from 11,203 households within 383 clusters (or areas) were selected from 2016-Nepal Demographic and Health survey. The index development involved sequential steps that included identification and screening of variables, variable reduction and extraction of the factors, and assessment of reliability and validity. Variables that could explain the underlying latent structure of area-level deprivation were selected from the dataset. These variables included: housing structure, household assets, and availability and accessibility of physical infrastructures such as roads, health care facilities, nearby towns, and geographic terrain. Initially, 26-variables were selected for the index development. A unifactorial model with 15-variables had the best fit to represent the underlying structure for area-level deprivation evidencing strong internal consistency (Cronbach's alpha = 0.93). Standardized scores for index ranged from 58.0 to 140.0, with higher scores signifying greater area-level deprivation. The newly constructed index showed relatively strong criterion validity with multi-dimensional poverty index (Pearson's correlation coefficient = 0.77) and relatively strong construct validity (Comparative Fit Index = 0.96; Tucker-Lewis Index = 0.94; standardized root mean square residual = 0.05; Root mean square error of approximation = 0.079). The factor structure was relatively consistent across different administrative regions. Area level deprivation index was constructed, and its validity and reliability was assessed. The index provides an opportunity to explore the area-level influence on disease outcome and health disparity.

Investigating Health Inequality Using Trend, Decomposition and Spatial Analyses: A Study of Maternal Health Service Use in Nepal.

Objectives: (a) To quantify the level and changes in socioeconomic inequality in the utilization of antenatal care (ANC), institutional delivery (ID) and postnatal care (PNC) in Nepal over a 20-year period; (b) identify key drivers of inequality using decomposition analysis; and (c) identify geographical clusters with low service utilization to inform policy. Methods: Data from the most recent five waves of the Demographic Health Survey were used. All outcomes were defined as binary variables: ANC (=1 if ≥4 visits), ID (=1 if place of delivery was a public or private healthcare facility), and PNC (=1 if ≥1 visits). Indices of inequality were computed at national and provincial-level. Inequality was decomposed into explanatory components using Fairile decomposition. Spatial maps identified clusters of low service utilization. Results: During 1996-2016, socioeconomic inequality in ANC and ID reduced by 10 and 23 percentage points, respectively. For PND, the gap remained unchanged at 40 percentage points. Parity, maternal education, and travel time to health facility were the key drivers of inequality. Clusters of low utilization were displayed on spatial maps, alongside deprivation and travel time to health facility. Conclusion: Inequalities in the utilization of ANC, ID and PNC are significant and persistent. Interventions targeting maternal education and distance to health facilities can significantly reduce the gap.

The double burden of malnutrition among women of reproductive age and preschool children in low- and middle-income countries: A scoping review and thematic analysis of literature.

The aim of this review was to map the literature on the double burden of malnutrition (DBM) among women of reproductive age (WRA) and preschool children in low- and middle-income countries (LMICs). The study aimed to provide an understanding of how DBM construct has been defined in the current literature and to elucidate plausible mechanisms underlying DBM development and its common risk factor among the two subgroups. We systematically searched for literature from the following databases: EMBASE, CINAHL, MEDLINE, LILACS, Scopus and ProQuest Dissertations & Thesis Global and identified articles that specifically reported on the coexistence of undernutrition and overnutrition sequalae at the population, household, or individual levels among WRA and preschool children in LMICs. A thematic analysis using the Braun and Clarke approach was conducted on excerpts from the articles to reveal emerging themes underlying the occurrence of DBM from the included studies. Of the initial 15 112 articles found, 720 met the inclusion criteria. Anthropometric measures for overnutrition and undernutrition including body mass index for WRA and height-for-age, weight-for-age, and weight-for-height Z-scores for preschool children were frequently used indicators for defining DBM across all levels of assessment. In fewer cases, DBM was defined by the pairing of cardiometabolic risk factors (e.g., hypertension) as measures for overnutrition and micronutrient deficiency (e.g., iron deficiency) as measures for undernutrition. The following themes emerged as plausible mechanisms for DBM development: nutrition transition, breastfeeding, diet behavior, biological mechanism, and statistical artifact. Factors such as child age, child sex, maternal age, maternal education, maternal occupation, household food security, household wealth, urbanicity, and economic development were commonly associated with most of the DBM phenotypes. Our review findings showed that the understanding of the DBM in current literature is very ambiguous. There is need for future research to better understand the DBM construct and its etiology.

Does the place of residence influence your risk of being hypertensive? A study-based on Nepal Demographic and Health Survey.

Even though several studies have examined various risk factors for hypertension, residential influence is poorly explored especially in the low-income countries. We aim to investigate the association between residential characteristics and hypertension in resource limited and transitional settings like Nepal. A total of 14,652 individuals aged 15 and above were selected from 2016-Nepal Demographic and Health Survey. Individuals with blood pressure ≥140/90 mmHg or a history of hypertension (as identified by physicians/health professionals) or under antihypertensive medication were defined as hypertensive. Residential characteristics were represented by area level deprivation index, with a higher score representing higher level of deprivation. Association was explored using a two-level logistic regression. We also assessed if residential area modifies the association between individual socio-economic status and hypertension. Area deprivation had a significant inverse association with the risk of hypertension. Individuals from the least deprived areas had higher odds of hypertension compared to highly deprived areas 1.59 (95% CI 1.30, 1.89). Additionally, the association between literacy a proxy of socio-economic status and hypertension varied with a place of residence. Literate individuals from highly deprived areas were likely to have a higher odds of hypertension compared to those with no formal education. In contrast, literate from the least deprived areas had lower odds of hypertension. These results identify counterintuitive patterns of associations between residential characteristics and hypertension in Nepal, as compared with most of the epidemiological data from high-income countries. Differential stages of demographic and nutritional transitions between and within the countries might explain these associations.

Examining the double burden of malnutrition for preschool children and women of reproductive age in low-income and middle-income countries: a scoping review protocol.

INTRODUCTION: The majority of the populations in low-income and middle-income countries (LMICs) are encountering the double burden of malnutrition (DBM): the coexistence of both undernutrition and overnutrition sequalae. With DBM being a new phenomenon in research, little is known about its aetiology, operational definitions and risk factors influencing its manifestation. The proposed scoping review is aimed at mapping literature with regard to the DBM phenomenon among preschool children and women of reproductive age in LMICs who are among the most high-risk groups to encounter DBM. METHODS: A comprehensive literature search will be conducted in the following electronic databases: MEDLINE, EMBASE, Scopus, CINAHL, LILACS and ProQuest Dissertations and Thesis Global. Additionally, searches in other government and institutional sources (WHO website and university repositories) and forward and backward citation tracking of seminal articles will also be done. Two reviewers will independently conduct title and abstract screening and full-text screening. Similarly, data extraction and coding will independently be done by two reviewers. Information extracted from included literature will be analysed qualitatively using thematic analysis approach and reported as per the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews guidelines. ETHICS AND DISSEMINATION: Ethical approval is not required for this study because the review is based on literature from publicly available sources. The dissemination of our findings will be done through presentations in relevant conferences and publication in a peer-reviewed journal.

Hypothesis and data-driven dietary patterns and colorectal Cancer survival: findings from Newfoundland and Labrador colorectal Cancer cohort.

BACKGROUND: Dietary patterns are commonly used in epidemiological research, yet there have been few studies assessing if and how research results may vary across dietary patterns. This study aimed to estimate the risk of mortality/recurrence/metastasis using different dietary patterns and comparison amongst the patterns. METHODS: Dietary patterns were identified by Cluster Analysis (CA), Principal Component Analysis (PCA), Alternate Mediterranean Diet score (altMED), Recommended Food Score (RFS) and Dietary Inflammatory Index (DII) scores using a 169-item food frequency questionnaire. Five hundred thirty-two colorectal cancer patients diagnosed between 1999 and 2003 in Newfoundland were followed-up until 2010. Overall Mortality (OM) and combined Mortality, Recurrence or Metastasis (cMRM) were identified. Comparisons were made with adjusted Cox proportional Hazards Ratios (HRs), correlation coefficients and the distributions of individuals in defined clusters by quartiles of factor and index scores. RESULTS: One hundred and seventy cases died from all causes and 29 had a cancer recurrence/metastasis during follow-up. Processed meats as classified by PCA (HR 1.82; 95% confidence interval (CI) 1.07-3.09), clusters characterized by meat and dairy products (HR 2.19; 95% CI 1.03-4.67) and total grains, sugar, soft drinks (HR 1.95; 95% CI 1.13-3.37) were associated with a higher risk of cMRM. Poor adherence to AltMED increased the risk of all-cause OM (HR 1.62; 95% CI 1.04-2.56). Prudent vegetable, high sugar pattern, RFS and DII had no significant association with both OM and cMRM. CONCLUSION: Estimation of OM and cMRM varied across dietary patterns which is attributed to the differences in the foundation of each pattern.

Inflammatory diet and risk for colorectal cancer: A population-based case-control study in Newfoundland, Canada.

OBJECTIVE: Chronic inflammation is implicated in causing cancer. Diet plays an important role in regulating chronic inflammation by altering circulating levels of inflammatory biomarkers. Effect of single food or nutrient on cancer often is inconclusive; perhaps due to dietary interactions and multicolinearity. The aim of this study was to determine prediagnostic inflammatory potential of overall diet in relation to risk for colorectal cancer (CRC). METHODS: In all, 547 patients with CRC from Newfoundland Familial Colorectal Cancer Registry and 685 controls from the general population were identified. Data on sociodemographic, medical history, lifestyle, and a 169-item food frequency questionnaire were collected retrospectively from both groups. Energy-adjusted Dietary Inflammatory Index (DII) score was calculated and used as both categorical and continuous variables for analysis. Odds ratio was estimated using multivariable logistic regression after adjusting potential confounders. A linear test for trend was performed using the median value in each quartile. RESULTS: Overall energy-adjusted mean DII score was -0.81 (range -5.19 to 6.93). Cases (-0.73 ± 1.5) had slightly higher DII scores than controls (-0.89 ± 1.6; P = 0.04). After adjusting the potential confounders, a statistically significant association was found between DII score and CRC risk. Using DII as a continuous variable (odds ratio [OR]continuous 1.10, 95% confidence interval [CI] 1.01-1.20) and categorical variable (ORquartile 1 versus 4 1.65, 95% CI 1.13-2.42; Ptrend = 0.02). CONCLUSION: Our findings indicate that proinflammatory diets are associated with an increased risk for CRC in the Newfoundland population.

Vitamin D receptor and calcium-sensing receptor polymorphisms and colorectal cancer survival in the Newfoundland population.

BACKGROUND: Increased serum levels of vitamin D and calcium have been associated with lower risks of colorectal cancer (CRC) incidence and mortality. These inverse associations may be mediated by the vitamin D receptor (VDR) and the calcium-sensing receptor (CASR). We investigated genetic variants in VDR and CASR for their relevance to CRC prognosis. METHODS: A population-based cohort of 531 CRC patients diagnosed from 1999 to 2003 in Newfoundland and Labrador, Canada, was followed for mortality and cancer recurrence until April 2010. Germline DNA samples were genotyped with the Illumina Omni-Quad 1 Million chip. Multivariate Cox models assessed 41 tag single-nucleotide polymorphisms and relative haplotypes on VDR and CASR in relation to all-cause mortality (overall survival, OS) and disease-free survival (DFS). RESULTS: Gene-level associations were observed between VDR and the DFS of rectal cancer patients (P=0.037) as well as between CASR and the OS of colon cancer patients (P=0.014). Haplotype analysis within linkage blocks of CASR revealed the G-G-G-G-G-A-C haplotype (rs10222633-rs10934578-rs3804592-rs17250717-A986S-R990G-rs1802757) to be associated with a decreased OS of colon cancer (HR, 3.15; 95% CI, 1.66-5.96). Potential interactions were seen among prediagnostic dietary calcium intake with the CASR R990G (Pint=0.040) and the CASR G-T-G-G-G-G-C haplotype for rs10222633-rs10934578-rs3804592-rs17250717-A986S-R990G-rs1802757 (Pint=0.017), with decreased OS time associated with these variants limited to patients consuming dietary calcium below the median, although the stratified results were not statistically significant after correction for multiple testing. CONCLUSIONS: Polymorphic variations in VDR and CASR may be associated with survival after a diagnosis of CRC.