Investigating sex and gender differences in dietary intake and the relationship with cardiometabolic diseases

A quarter of adult deaths are attributable to suboptimal diets globally, with cardiovascular (CVD) and metabolic diseases being the leading cause of diet-related deaths. The aim of this thesis was to investigate the relationship of sex and gender with diet and cardiometabolic diseases via a range of geographically diverse studies, through a mixed methods approach. Three quantitative studies focusing on sex differences were conducted: one looking at biases in relation to self-reported energy intake by a systematic review and meta-analysis; one cross-sectional analysis of dietary behaviours and associations with cardiometabolic risk factors in seven low- and middle-income countries (LMICs); and a prospective analysis of cohort data from the UK looking at dietary intake and associated risks of CVD and premature mortality. Questions arising from these studies were explored through qualitative studies in Fiji: a policy landscape analysis and focus group discussions to understand gender differences in diet knowledge, attitudes and behaviours and gender considerations in policies. No sex bias in the accuracy of dietary assessment was identified, with similar levels of energy underestimation by women and men. Across the seven LMICs in the cross-sectional analysis, both women and men had poor dietary behaviours, however, women who reported positive (good) salt use behaviour were less likely to have undiagnosed hypertension (not evident for men). Diets of women and men were also poor in the UK cohort, yet an association between specific combinations of macronutrients and a reduced risk of mortality was identified for women and men, and a reduced risk of CVD for men. The policy analysis conducted in Fiji revealed a conflation between “gender” and “reproductive health”, and that gender differences in diet-related diseases were not viewed as policy issues. Finally, the focus group discussions identified gender constructs around food, however, upstream determinants of poor diets such as climate change and socioeconomic factors were identified as crucial influences on diet, by women and men. Collectively, findings identified poor diets for both sexes, with some modest sex differences in associations between diet and disease, which are unlikely due to differences in reporting. Results from the qualitative studies highlight the importance of considering gender in view of other equity factors. These findings will be important in the development of equitable food policy globally

Contextualising sex and gender research to improve women's health: An early- and mid-career researcher perspective

The field of sex and gender research in health and medicine is growing, and many early- and mid-career researchers (EMCRs) are developing skills in this area. As EMCRs specialising in sex and gender research, we aim to better understand sex- and gender-based determinants of human health, challenge long-standing and pervasive gender biases, and contribute to improving the evidence base upon which clinical guidelines and policy interventions are developed. To effectively achieve these goals, we believe that EMCRs would benefit from understanding the challenges of working in this space and participate in driving change in three key areas. First, in creating greater links between the goals of sex and gender research and addressing systemic bias against women and gender minorities, to effectively translate knowledge about sex and gender differences into improved health outcomes. Second, in expanding the reach of sex and gender research to address women's health in an intersectional way and ensure that it also benefits the health of men, transgender and gender-diverse people and those who are intersex. Third, in working with others in the scientific community to improve methods for sex and gender research, including updating data collection practises, ensuring appropriate statistical analyses and shifting scientific culture to recognise the importance of null findings. By improving focus on these three areas, we see greater potential to translate this research to improve women's health and reduce health inequities for all

Gender differences in the accuracy of dietary assessment methods to measure energy intake in adults:protocol for a systematic review and meta-analysis

Introduction Diet is an important modifiable risk factor for many chronic diseases. Measurement of dietary intake usually relies on self-report, subject to multiple biases. There is a need to understand gender differences in the self-report of dietary intake and the implications of any differences in targeting nutrition interventions. Literature in this area is limited and it is currently unknown whether self-report dietary assessment methods are equally accurate for women and men. The aim of this systematic review is to determine whether there are differences by gender in reporting energy intake compared with a reference measure of total energy expenditure. Methods and analysis A comprehensive search of published original research studies will be performed in MEDLINE, Scopus, Web of Science, EMBASE, CINAHL and Cochrane library. Original research studies will be included if they were conducted in free-living/unhospitalised adults and included a measure for both women and men of (a) self-reported energy intake and (b) total energy expenditure by doubly labelled water. One author will conduct the electronic database searches, two authors will independently screen studies, conduct a quality appraisal of the included studies using standardised tools and extract data. If further information is needed, then study authors will be contacted. If appropriate, a random-effects meta-analysis will be conducted, with inverse probability weighting, to quantify differences in the mean difference in agreement between reported energy intake and measured energy expenditure between women and men, by self-report assessment method. Subgroup analyses will be conducted by participant factors, geographical factors and study quality. Ethics and dissemination All data used will be from published primary research studies or deidentified results provided at the discretion of any study authors that we contact. We will submit our findings to a peer-reviewed scientific journal and will disseminate results through presentations at international scientific conferences. PROSPERO registration number CRD42019131715

Evaluation of sex differences in dietary behaviours and their relationship with cardiovascular risk factors:a cross-sectional study of nationally representative surveys in seven low- and middle-income countries

Background: Cardiovascular diseases (CVD) are the leading causes of death for men and women in low-and-middle income countries (LMIC). The nutrition transition to diets high in salt, fat and sugar and low in fruit and vegetables, in parallel with increasing prevalence of diet-related CVD risk factors in LMICs, identifies the need for urgent action to reverse this trend. To aid identification of the most effective interventions it is crucial to understand whether there are sex differences in dietary behaviours related to CVD risk. Methods: From a dataset of 46 nationally representative surveys, we included data from seven countries that had recorded the same dietary behaviour measurements in adults; Bhutan, Eswatini, Georgia, Guyana, Kenya, Nepal and St Vincent and the Grenadines (2013-2017). Three dietary behaviours were investigated: positive salt use behaviour (SUB), meeting fruit and vegetable (F&V) recommendations and use of vegetable oil rather than animal fats in cooking. Generalized linear models were used to investigate the association between dietary behaviours and waist circumference (WC) and undiagnosed and diagnosed hypertension and diabetes. Interaction terms between sex and dietary behaviour were added to test for sex differences. Results: Twenty-four thousand three hundred thirty-two participants were included. More females than males reported positive SUB (31.3 vs. 27.2% p-value < 0.001), yet less met F&V recommendations (13.2 vs. 14.8%, p-value< 0.05). The prevalence of reporting all three dietary behaviours in a positive manner was 2.7%, varying by country, but not sex. Poor SUB was associated with a higher prevalence of undiagnosed hypertension for females (13.1% vs. 9.9%, p-value = 0.04), and a higher prevalence of undiagnosed diabetes for males (2.4% vs. 1.5%, p-value = 0.02). Meeting F&V recommendations was associated with a higher prevalence of high WC (24.4% vs 22.6%, p-value = 0.01), but was not associated with undiagnosed or diagnosed hypertension or diabetes. Conclusion: Interventions to increase F&V intake and positive SUBs in the included countries are urgently needed. Dietary behaviours were not notably different between sexes. However, our findings were limited by the small proportion of the population reporting positive dietary behaviours, and further research is required to understand whether associations with CVD risk factors and interactions by sex would change as the prevalence of positive behaviours increases

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P &lt; 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

A retrospective study on the growth trajectories and nutritional support of preterm infants admitted to the Neonatal Intensive Care Unit at Dunedin Hospital

Introduction Premature infants are at high risk of undernutrition and extrauterine growth restriction (EUGR) and thus, monitoring of growth is crucial for optimizing the health and well-being of this vulnerable population group. The newly published INTERGROWTH-21st Preterm Growth Standard released in late 2015 provides the first prescriptive growth trajectory of how an infant should grow however, it has not yet been implemented clinically. Objectives Thus, the aim of the present study is i) to determine if differences in growth z-scores and risk of undernutrition among preterm infants born < 33 weeks gestation exist between the INTERGROWTH standard and commonly used NZ growth reference charts; and ii) to assess the growth trajectory of a sample population of preterm infants < 33 weeks gestational age admitted to a New Zealand tertiary care facility using the INTERGROWTH standard, and evaluate the relation between feeding practices and these growth outcomes from birth to approximately 48 weeks Post Menstrual Age (PMA). Results and Discussion Longitudinal data were retrospectively collected on infants born < 33 weeks gestation admitted to Dunedin NICU between January 2013 and June 2015. Weight, length and head circumference at birth, 28 days of life (28-DOL), 36 weeks and 48 weeks PMA were collected, z-scores were calculated using the INTERGROWTH Preterm Growth Standard, and commonly used UK-90 and Fenton Preterm Growth References. A number of different classifications were used to define insufficient growth including the proportion of infants classified with a z-score of < -1.28 SD (less than the 10th chart centile), z-score ≥ -2 & <-1 SD) often used to assess ‘at risk’ and a z-score SD <-2 used to define stunting and underweight. McNemar chi-squared test and paired t-tests were employed to assess whether significant differences in classification existed between the INTERGROWTH standard and the growth reference charts. Growth velocity (g/kg/day) was determined via an exponential model from birth to 36 weeks PMA and the post-discharge period from 36 weeks PMA to 48 weeks PMA. Nutritional practices including enteral nutrition, withholding of feeds, nutrient intake at 36 weeks PMA and feeding at discharge were described. Multiple regression was used to explore associations between growth outcomes and nutritional variables. In total, data were collected on 103 preterm infants. Mean (SD) gestational age of infants was 29.1 (2.5) weeks and birth weight was 1290 (403) g. A comparison of the growth using the different charts revealed significant z-score differences, specifically for weight z-score ≥ -2 & <-1 at birth, head circumference at birth across all categories, and length z-score < -1.28 SD at 36 weeks PMA. Overall, mean z-scores determined using the UK-90 were significantly lower for all growth measures at birth and 36 weeks PMA compared with the INTERGROWTH (all, P<0.001) with the exception of weight-for-age at 36 weeks PMA An overall evaluation of preterm growth using the INTERGROWTH standard revealed that the prevalence of growth faltering (weight-for-age z-score <-1.28) increased from 9% at birth to 13% at 28-DOL, 19% at 36 weeks and 30% at 48 weeks PMA. Mean (SD) GV in-hospital [14.2 (3.3) g/kg/d] declined substantially post-discharge [8.2 (1.7) g/kg/d], falling well below the desirable rate of 18g/kg/d. Weight at 28-DOL was a significant predictor of improved growth through to 48 weeks PMA. Fortified human milk in hospital was positively associated with length at 36 weeks PMA while reported feeding of infant formula at discharge was associated with improved head circumference at 48 weeks PMA. Conclusion Differences were evident between the INTERGROWTH Preterm Growth Standard, with the UK-90 exhibiting the most pronounced differences and misidentification of infants at risk of poor growth. Secondly, EUGR was highly prevalent in this sample population of preterm infants. Optimal growth in the first month of life appears critical for the support of desirable postnatal growth outcomes and reinforces the need for early nutritional support. In addition, a greater emphasis on post-discharge nutrition and growth monitoring is warranted in this sample population

Understanding Barriers and Enablers to State Action on Salt: Analysis of Stakeholder Perceptions of the VicHealth Salt Reduction Partnership

The Victorian Salt Reduction Partnership (VicSalt Partnership) was launched in 2015, bringing together health and research organisations to develop an action plan for salt reduction interventions at a state level. A comprehensive evaluation was designed to assess the impact of the resulting four-year intervention strategy. As part of the process evaluation, semi-structured interviews were undertaken with stakeholders in March&ndash;May 2017, to understand perceived barriers and enablers to effective strategy implementation. Data were coded in relation to the key topic areas of the interviews with an inductive method used to analyse themes within topics. Seventeen stakeholders were contacted, 14 completed an interview; five from state government or statutory agencies, four from non-government funded organisations, four from research organisations and one from the food industry. Twelve were members of the VicSalt Partnership and two were informal collaborators. Most stakeholders viewed the VicSalt Partnership as a positive example of working collaboratively, and said this was essential for raising awareness of the importance of salt reduction with consumers, the food industry, and the government. Challenges relating to engaging the food industry and federal government through a state-led initiative were identified. New approaches to overcome this, such as forming clear &ldquo;asks&rdquo; to government and committing industry to &ldquo;pledges&rdquo; on reformulation were suggested. Stakeholder interviews and qualitative analysis have provided a range of important insights into barriers and enablers, many of which have already been used to strengthen intervention implementation. The evaluation of the VicSalt Partnership is ongoing and the program is expected to provide a wealth of lessons for state-led interventions to reduce salt intake in Australia and globally

Strengthening Sugar-Sweetened Beverage Taxation for Non-Communicable Disease Prevention: A Comparative Political Economy Analysis Case Study of Fiji and Tonga

Diet-related fiscal policy is an effective NCD prevention strategy. However, current sugar-sweetened beverage (SSB) taxes in Fiji and Tonga have not had the desired effect; SSB consumption in Fiji, for example, contributes to mortality more than double the global rates and is highest in the WHO Western Pacific Region. We therefore aimed to better understand the perceived underlying political economy drivers that have and continue to affect change in each country. Our study design utilised a comparative case study that triangulated documentary policy and stakeholder analysis with semi-structured stakeholder interviews in both countries and an in-depth corporate political activity analysis in Fiji. We drew on theoretical frameworks relevant to political economy to collect and analyse policy and stakeholder data, and utilised established corporate political activity frameworks to analyse industry activity. Common findings to both Fiji and Tonga suggested that the SSB tax impact could be increased through multisectoral engagement, embracing a whole-of-society approach, strengthened institutional structures and leveraging off competing priorities across sectors towards more common goals. These findings provide opportunities and lessons for Fiji and Tonga as well as other similar settings seeking to strengthen or upscale the impact of diet-related fiscal policy