Mediterranean Diet Adherence and Health-Related Quality of Life during Pregnancy: Is the Mediterranean Diet Beneficial in Non-Mediterranean Countries?

This study aimed to examine the association of Mediterranean diet (MD) adherence and MD components with health-related quality of life (HRQoL) in pregnant women from Spain and Sweden. A total of 138 pregnant women from Spain (age: 32.9 ± 4.6 years old) and 302 pregnant women from Sweden (age: 31.3 ± 4.1 years old) were included. MD adherence was assessed with the Mediterranean food pattern (i.e., a MD index) at the 14-16th gestational weeks. HRQoL was assessed with the Spanish and Swedish versions of the 36-item Short-Form Health Survey (SF-36 and RAND-36, respectively) at the 14-16th and 34-37th gestational weeks. A greater MD adherence was associated with better physical functioning, bodily pain, vitality, emotional role, and mental health in cross-sectional associations (2nd trimester) in the Spanish sample (all p < 0.05). Furthermore, a greater MD adherence was associated with lower bodily pain in both Spanish and Swedish samples (both p < 0.05) in the 3rd trimester. The associations of MD adherence with pain seem to be explained by a greater intake of fiber, fish, fruits, nuts, and legumes (all p < 0.05). A greater MD adherence, driven by a higher intake of fiber, fish, fruits, nuts, and legumes, was associated with lower pain throughout pregnancy in both Mediterranean and non-Mediterranean populations.

To capture the child's interest - nurses experiences of 'Saga stories in health talks'.

BACKGROUND: As unhealthy lifestyle habits have been found to be established early in life and often track into adulthood, early preventive initiatives are important. 'Saga Stories in health talks' is a newly developed material that is intended to be used as a support for nurses at child health care (CHC) centers in their health talks with children and parents in Sweden. The aim of this study is to explore how CHC nurses experience the usability of the 'Saga Stories in health talks' material. METHODS: This study used a qualitative design. The material 'Saga Stories in health talks' was tested by 33 CHC nurses working in 11 CHC centers in three regions in Sweden. All CHC nurses were invited to participate in the interviews and 17 agreed. The interviews were transcribed and analysed using content analysis. RESULTS: Three categories and eight sub-categories emerged. The categories were: (1) An appreciated tool suitable for health talks, (2) Illustrations to capture children's interest in the conversation with families, and (3) Barriers and facilitators. Saga Stories in health talks' was experienced by the CHC nurses as an appreciated tool with content highly relevant to what should be discussed during the health talks. The CHC nurses described the material as well-designed with illustrations that helped them capture the child's interest and increase their participation, while still involving the parents. Support from colleagues, the researchers, and managers were seen as important facilitators. Challenges included structural factors such as how and when to best use the material, especially concerning that the 4-year visit contained many other mandatory parts. CONCLUSIONS: This pilot study show that the material 'Saga Stories in health talks' was highly appreciated by CHC nurses and facilitated their health talks with families in CHC. Important aspects with the material were the relevant content and the focus on healthy living habits, as well as the child friendly illustrations. These findings can be used when similar material is developed to facilitate health talks with families in other contexts. Our results also highlight the importance to adjust the implementation of a new material with already established practice and routines.

Hyperactivity in preschool age is associated with higher fat-free mass and healthy lifestyle behaviours five years later: A longitudinal study of Swedish children.

BACKGROUND: There is evidence for a link between hyperactivity and obesity, especially among older children. Both conditions seem to be multifactorial in origin and hypotheses of common underlying issues, such as emotional dysregulation, have been suggested. However, studies of the co-occurrence of the two conditions in younger age groups have been inconclusive. OBJECTIVES: We aimed to study the longitudinal associations of psychological strengths and difficulties at 4 years of age with health behaviours, body composition, physical fitness, and cardiovascular disease (CVD) risk factors 5 years later. METHODS: Parents of 226 4-year-old children filled out the Strengths and Difficulties Questionnaire (SDQ). At 9 years of age, we assessed health behaviours, physical fitness, body composition, and CVD risk factors. Associations were examined with linear regression models that were adjusted for sex, age of the child at 9, and maternal education. RESULTS: In the adjusted models, hyperactivity at 4 was associated with higher fat-free mass (ß = 0.18, p = 0.007) and lower levels of sedentary behaviour (ß -0.14, p = 0.043) at 9 years. Furthermore, greater emotional problems at 4 were associated with lower intake of fruit and vegetables (ß -0.14, p = 0.038) at 9 years. However, there were no statistically significant associations between psychological difficulties and fat-mass index. CONCLUSIONS: Our novel data provide no evidence of an association between hyperactivity in preschool age and obesity or obesity-related behaviours in school age. Future studies examining how psychological factors relate to obesity development should consider a developmental perspective.

Effectiveness of a Smartphone App (MINISTOP 2.0) integrated in primary child health care to promote healthy diet and physical activity behaviors and prevent obesity in preschool-aged children: randomized controlled trial.

BACKGROUND: Childhood overweight and obesity is a public health priority. We have previously reported the efficacy of a parent-oriented mobile health (mHealth) app-based intervention (MINISTOP 1.0) which showed improvements in healthy lifestyle behaviors. However, the effectiveness of the MINISTOP app in real-world conditions needs to be established. OBJECTIVE: To evaluate the real-world effectiveness of a 6-month mHealth intervention (MINISTOP 2.0 app) on children's intake of fruits, vegetables, sweet and savory treats, sweet drinks, moderate-to-vigorous physical activity, and screen time (primary outcomes), and on parental self-efficacy (PSE) for promoting healthy lifestyle behaviors, and children's body mass index (BMI) (secondary outcomes). METHODS: A hybrid type 1 effectiveness-implementation design was utilized. For the effectiveness outcomes, a two-arm, individually randomized controlled trial was conducted. Parents (n = 552) of 2.5-to-3-year-old children were recruited from 19 child health care centers across Sweden, and, randomized to either a control (standard care) or intervention group (MINISTOP 2.0 app). The 2.0 version was adapted and translated into English, Somali and Arabic to increase reach. All recruitment and data collection were conducted by the nurses. Outcomes were assessed at baseline and after six months, using standardized measures (BMI) and a questionnaire (health behaviors, PSE). RESULTS: Among the participating parents (n = 552, age: 34.1 ± 5.0 years), 79% were mothers and 62% had a university degree. Twenty-four percent (n = 132) of children had two foreign-born parents. At follow-up, parents in the intervention group reported lower intakes of sweet and savory treats (-6.97 g/day; p = 0.001), sweet drinks (-31.52 g/day; p < 0.001), and screen time (-7.00 min/day; p = 0.012) in their children compared to the control group. The intervention group reported higher total PSE (0.91; p = 0.006), PSE for promoting healthy diet (0.34; p = 0.008) and PSE for promoting physical activity behaviors (0.31; p = 0.009) compared to controls. No statistically significant effect was observed for children's BMI z-score. Overall, parents reported high satisfaction with the app, and 54% reported using the app at least once a week. CONCLUSION: Children in the intervention group had lower intakes of sweet and savory treats, sweet drinks, less screen time (primary outcomes) and their parents reported higher PSE for promoting healthy lifestyle behaviors. Our results from this real-world effectiveness trial support the implementation of the MINISTOP 2.0 app within Swedish child health care. TRIAL REGISTRATION: Clinicaltrials.gov NCT04147039; https://clinicaltrials.gov/ct2/show/NCT04147039.

Study protocol for an effectiveness-implementation hybrid trial to evaluate a health promotion intervention in parents and their 5-year-old child: Saga Stories in health talks in Swedish child healthcare.

BACKGROUND: Unhealthy lifestyle behaviours such as a poor diet, inadequate physical activity, and excessive screen time have been shown to be established in childhood and track into adulthood, demonstrating the need for health promotion interventions in the pre-school years. The overall aim of this project is to: (i) evaluate the effectiveness of `Saga Stories in health talks´ within child healthcare (CHC) on parental self-efficacy to promote healthy diet, physical activity, and screen time behaviours in their child; children's intake of key dietary indicators and screen time and (ii) evaluate and explore the implementation of `Saga Stories in health talks´ with regards to acceptability, appropriateness, feasibility, fidelity, adoption, sustainability, satisfaction, and usage. METHODS: A hybrid type I effectiveness-implementation trial will be conducted. A cluster randomized controlled trial will be used to assess the effectiveness of `Saga Stories in health talks´ in 42 CHC centers across six regions in Sweden. `Saga Stories in health talks´ consists of material for CHC nurses to use to facilitate the health talk with both the child and parent(s) and is complemented with take-home material. Parent and child dyads are recruited (n = 450) from participating CHC centers when they attend their 5-year routine visit. The intervention group receives the health talk using Saga Stories and take-home material, whereas the control group receives the standard health talk. The primary outcome is parental self-efficacy to promote healthy diet, physical activity, and screen time behaviours in their child and secondary outcomes include children's intake of key dietary indicators and screen time. All outcomes are assessed at baseline and 2-months post-intervention. The implementation outcomes that will be assessed are: acceptability, appropriateness, feasibility, satisfaction, usage, fidelity, adoption, and sustainability (assessed quantitatively and qualitatively). DISCUSSION: The Swedish National Board of Health and Welfare have identified the need of more material, education, and working methods for promoting healthy lifestyle behaviours in CHC. Following this trial `Saga Stories in health talks´ has great potential to be implemented in CHC across Sweden to aid nurses to promote and support healthy lifestyle behaviours in pre-school children and their families. TRIAL REGISTRATION: ClinicalTrials.gov , NCT05237362 . Registered 2 February 2022.

Online reach and engagement of a child nutrition peer-education program (PICNIC): insights from social media and web analytics.

BACKGROUND: Parents frequently seek parental advice online and on social media; thus, these channels should be better utilized in child health interventions. The Parents in Child Nutrition Informing Community (PICNIC) program aims to facilitate peer-to-peer sharing of evidence-based child feeding information and support parents within their social networks. The present study aimed to explore web and social media analytics to evaluate reach and user engagement with the PICNIC online components. METHODS: Online user activity data from the PICNIC Facebook closed group and public Page were collected through Facebook Insights, and program-specific website traffic data through Google Analytics. Analytics data from Nov-2019 to April-2021 was evaluated through visualisation and summary statistics to obtain insights into program growth and current reach in Australia, compare demographics of audience reached through the online channels, and explore parents' use and engagement in PICNIC content. RESULTS: Results showed steady program growth in the 18 months of recruitment; participant numbers grew from 102 to 261 peer educators while the Facebook Page audience increased threefold, totalling 1615 followers. Intervention posts shared on Facebook (4-5 posts/week) typically reached only a portion of PICNIC Page followers each week, but also reached a wider audience through their friends. Throughout the evaluated period, Facebook users actively engaged in PICNIC posts, although the level of engagement varied considerably from post to post. Furthermore, results from this study suggest the strategy of directing potentially interested parents from social media to the website for program sign-up was successful. Finally, the explored data gave insights into users' availability, demographics and engagement, which will be used to inform refinement of the PICNIC website and social media strategies. CONCLUSIONS: Our findings confirm the benefits of using a peer education approach and existing social network channels to disseminate evidence-based child feeding information to parents. This study also demonstrates the usefulness of web and social media analytics to be used as part of a continuous evaluation for gaining insight to inform further development and improvement of program strategies. TRIAL REGISTRATION: The PICNIC project was retrospectively submitted for registration with the Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12622000230752 (09/02/2022).

Body composition, physical fitness and cardiovascular risk factors in 9-year-old children.

The independent associations of body composition and physical fitness components with cardiovascular disease (CVD) risk factors in childhood are not fully understood. Thus, this cross-sectional study examined the independent associations of body composition and physical fitness with CVD risk factors in Swedish 9-year-old children (n = 411). Unadjusted linear regression analyses showed that body mass index (BMI), % fat mass and fat mass index were all positively associated with systolic and diastolic blood pressure, Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) and Metabolic Syndrome (MetS) score (all ß ≥ 0.229, P ≤ 0.001). These associations were virtually unaffected by adjustments for basic covariates (child's age and sex, maternal educational level and maternal BMI), fat-free mass and physical fitness. Fat-free mass index had generally weak associations with CVD risk factors and no associations were statistically significant after adjustments (all P > 0.27). Greater cardiorespiratory fitness and motor fitness were associated with lower HOMA-IR and MetS score in unadjusted models (all ß ≤ - 0.158, P ≤ 0.039) but not after adjustments for basic covariates and body composition. These findings indicate that cardiovascular health promotion in childhood may focus on the maintenance of a healthy fat mass.

Self-reported (IFIS) versus measured physical fitness, and their associations to cardiometabolic risk factors in early pregnancy.

Physical fitness is a strong marker of health, but objective fitness measurements are not always feasible. The International FItness Scale (IFIS) for self-reported fitness is a simple-to-use tool with demonstrated validity and reliability; however, validation in pregnancy needs to be confirmed. Also, its association with cardiometabolic health in pregnant women is unknown. Hence, we examined (1) the validity of the IFIS with objectively measured fitness, and (2) the associations of self-reported versus objectively measured cardiorespiratory fitness (CRF) and muscular strength with cardiometabolic risk factors in early pregnancy. Women (n = 303) from the HealthyMoms trial were measured at gestational week 14 for: CRF (6-min walk test); upper-body muscular strength (handgrip strength test); self-reported fitness (IFIS), body composition (air-displacement plethysmography); blood pressure and metabolic parameters (lipids, glucose, insulin). Higher self-reported fitness was associated with better measured fitness (ANOVA overall p < 0.01 for all fitness types), indicating the usefulness of the IFIS in pregnancy. Furthermore, higher self-reported overall fitness and CRF were associated with lower cardiometabolic risk scores (ANOVA p < 0.001), with similar results shown for measured CRF (ANOVA p < 0.001). The findings suggest that IFIS could be useful to stratify pregnant women in appropriate fitness levels on a population-based level where objective measurement is not possible.

How to Support Child Healthcare Nurses in Sweden to Promote Healthy Lifestyle Behaviors from the Start of Life.

Child healthcare (CHC) nurses have a key role in promoting and supporting healthy lifestyle behaviors from a young age. Thus, this study aims to investigate the perspectives of CHC nurses regarding discussing food introduction, physical activity/active play, and screen time with parents; explore facilitators and barriers influencing the discussion of healthy lifestyle behaviors with parents; and explore the perspectives of CHC nurses regarding a complementary program to promote healthy lifestyle behaviors from the start of life. A total of fifteen nurses participated in semi-structured interviews, which were recorded, transcribed verbatim, and analyzed using thematic analysis. There were four themes that were generated: parental needs; facilitators and barriers; parental groups; and future working methods. This study found that CHC nurses have seen an increase in the need for support among today's parents. Time, the need to tailor information, and confidence to address sensitive topics were perceived as the largest barriers during daily work for the nurses. Furthermore, large variations in parental groups were found. Finally, the CHC nurses displayed a willingness and openness to change and develop current working methods using digital solutions. These solutions could possibly ease the workload and at the same time, support parents to create healthy lifestyle behaviors from the start of their child's life.

Effectiveness of a Smartphone App to Promote Healthy Weight Gain, Diet, and Physical Activity During Pregnancy (HealthyMoms): Randomized Controlled Trial.

BACKGROUND: Excessive gestational weight gain (GWG) during pregnancy is a major public health concern associated with negative health outcomes for both mother and child. Scalable interventions are needed, and digital interventions have the potential to reach many women and promote healthy GWG. Most previous studies of digital interventions have been small pilot studies or have not included women from all BMI categories. We therefore examined the effectiveness of a smartphone app in a large sample (n=305) covering all BMI categories. OBJECTIVE: To investigate the effectiveness of a 6-month intervention (the HealthyMoms app) on GWG, body fatness, dietary habits, moderate-to-vigorous physical activity (MVPA), glycemia, and insulin resistance in comparison to standard maternity care. METHODS: A 2-arm parallel randomized controlled trial was conducted. Women in early pregnancy at maternity clinics in Östergötland, Sweden, were recruited. Eligible women who provided written informed consent completed baseline measures, before being randomized in a 1:1 ratio to either an intervention (n=152) or control group (n=153). The control group received standard maternity care while the intervention group received the HealthyMoms smartphone app for 6 months (which includes multiple features, eg, information; push notifications; self-monitoring; and feedback features for GWG, diet, and physical activity) in addition to standard care. Outcome measures were assessed at Linköping University Hospital at baseline (mean 13.9 [SD 0.7] gestational weeks) and follow-up (mean 36.4 [SD 0.4] gestational weeks). The primary outcome was GWG and secondary outcomes were body fatness (Bod Pod), dietary habits (Swedish Healthy Eating Index) using the web-based 3-day dietary record Riksmaten FLEX, MVPA using the ActiGraph wGT3x-BT accelerometer, glycemia, and insulin resistance. RESULTS: Overall, we found no statistically significant effect on GWG (P=.62); however, the data indicate that the effect of the intervention differed by pre-pregnancy BMI, as women with overweight and obesity before pregnancy gained less weight in the intervention group as compared with the control group in the imputed analyses (-1.33 kg; 95% CI -2.92 to 0.26; P=.10) and completers-only analyses (-1.67 kg; 95% CI -3.26 to -0.09; P=.031]). Bayesian analyses showed that there was a 99% probability of any intervention effect on GWG among women with overweight and obesity, and an 81% probability that this effect was over 1 kg. The intervention group had higher scores for the Swedish Healthy Eating Index at follow-up than the control group (0.27; 95% CI 0.05-0.50; P=.017). We observed no statistically significant differences in body fatness, MVPA, glycemia, and insulin resistance between the intervention and control group at follow up (P≥.21). CONCLUSIONS: Although we found no overall effect on GWG, our results demonstrate the potential of a smartphone app (HealthyMoms) to promote healthy dietary behaviors as well as to decrease weight gain during pregnancy in women with overweight and obesity. TRIAL REGISTRATION: ClinicalTrials.gov NCT03298555; https://clinicaltrials.gov/ct2/show/NCT03298555. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/13011.

Engaging New Parents in the Development of a Peer Nutrition Education Model Using Participatory Action Research.

This study investigated the implementation model and research methods of a peer education program for new parents focused on infant feeding and nutrition. Two hundred and sixty-nine parents with an infant aged birth to two years old were invited to become co-researchers in a Participatory Action Research (PAR) study over three years. Data included focus group and online participant meeting transcripts, social media data, correspondence between the implementation team and peer educators, and field notes. All data were consolidated regularly and discussed by project participants and the research team. After each PAR cycle, structured content analysis was conducted, informing the next iteration of the implementation model and research methods. Participating parents were highly engaged in child feeding peer-to-peer education, but felt more effective and comfortable being considered as a child-feeding information resource sharer or 'champion' rather than a formal peer educator. Similarly, quantitative data collection was only effective when it was integrated seamlessly into the implementation model. PAR methodology suited the diversity and dynamic real-life study setting, facilitating substantial improvements to the peer nutrition intervention model and data collection methods. Our study demonstrated that a genuine collaboration between health professionals and participants to implement research in practice can achieve both intervention outcomes and research aims.

The Need for an Evidence-Based Program in Sweden to Support Parents to Create Healthy Lifestyle Behaviors from the Start of Life-Parental Perceptions.

In Sweden, there have been no interventions promoting the development of healthy lifestyle behaviors starting in infancy. Thus this paper aims to: (i) investigate Swedish parents' experiences regarding feeding of solid foods, screen time, and physical activity in healthy infants; (ii) investigate parents' needs and perceptions regarding information/support provided in primary child healthcare (CHC) and (iii) explore whether a parenting program focused on child diet and active play would be relevant and utilized. Semi-structured interviews were conducted with 20 parents. These were recorded, transcribed verbatim and analyzed using thematic analysis. Seven themes emerged: Feeling excited to enter a new phase; Parents' responsibility of doing it "right" can be stressful; Motivated to learn during specific time windows; Information to trust; The importance of social support from peers; Experiences of support received from CHC; and the Infant, Feeding, Activity, and Nutrition Trial (INFANT) for a Swedish context. Parents were excited to enter new phases in their child's development. However, this came with worry they were doing things "right", leading parents to want more information/support. Overall, Swedish parents were very positive about the prospects of engaging in a primary CHC delivered program to support them to promote healthy lifestyle behaviors from birth and felt this could complement the care currently provided.

International Study of Movement Behaviors in the Early Years (SUNRISE): Results from SUNRISE Sweden's Pilot and COVID-19 Study.

The International Study of Movement Behaviors in the Early Years (SUNRISE) was initiated in response to the 2019 WHO guidelines for physical activity, sedentary behavior, and sleep in children aged 0-5 years. This Swedish pilot study aimed to: (i) assess the proportion of preschoolers meeting the guidelines, (ii) evaluate the feasibility of the methods for the SUNRISE study, and (iii) assess how movement behaviors have been affected in preschoolers during the COVID-19 pandemic. Physical activity and sleep (waist-worn ActiGraph); screen time and movement behaviors (parental questionnaire); motor skills (Ages and Stages Questionnaire); and executive functions (3 iPad games) were assessed in 100 Swedish preschoolers (n = 58 boys). There were 19.4% of preschoolers (n = 14) who met the WHO guidelines. The motor skill and executive function assessments were feasible; however, 20% refused to wear the ActiGraph overnight. Additionally, during the pandemic Swedish children's physical activity, time spent outside on weekdays and weekend days, and screen time significantly increased (+53; +124; +68; +30min/day, respectively, all p-values ≤ 0.001). Methods for the SUNRISE study were feasible in a Swedish context; however, considerations to switch to a wrist-worn accelerometer should be made. Furthermore, children's physical activity increased during the pandemic, which is likely due to how the rules/restrictions were implemented in Sweden.

MINISTOP 2.0: a smartphone app integrated in primary child health care to promote healthy diet and physical activity behaviours and prevent obesity in preschool-aged children: protocol for a hybrid design effectiveness-implementation study.

BACKGROUND: Childhood obesity is still a major health problem in many countries, including Sweden. Childhood obesity and obesity-related behaviours in childhood, such as low physical activity and unhealthy eating habits, tend to track into adulthood, which highlights the need for early prevention. Our aims are to evaluate whether a parent-oriented mobile health app (the MINISTOP 2.0 app) integrated into primary child health care can improve diet and physical activity behaviours and reduce the prevalence of overweight and obesity in preschool-aged children as well as to evaluate the implementation among child health care nurses and parents. METHODS: This trial uses a hybrid type 1 effectiveness-implementation design. Families (n = 500) who attend a routine visit to one of 15-20 primary child health care centres throughout Sweden, when their child is 2.5 years, are offered participation in a randomised controlled trial (effectiveness evaluation). After acceptance, families will be randomised (1:1) to control or intervention groups. The intervention group receives a 6-month parent-oriented smartphone intervention aimed at improving the dietary and activity behaviours of their child (the MINISTOP 2.0 app) and the control group receives routine child health care. Dietary habits, physical activity and screen time (primary outcomes), body weight and height in children, and parental self-efficacy (secondary outcomes) are measured at baseline and at 6 months post randomisation. Implementation outcomes (i.e. perceived acceptability, appropriateness, and feasibility) of the intervention will be assessed among primary child health care nurses and parents in the trial through questionnaires and qualitative interviews. DISCUSSION: This trial will evaluate whether the MINISTOP 2.0 app can be used in primary child health care to improve diet and physical activity behaviours, and prevent overweight and obesity, in preschool-aged children. If effectiveness is proven, and the MINISTOP 2.0 app is considered acceptable, appropriate and feasible, it can be implemented nationally as part of the preventive strategies to combat childhood obesity provided by routine child health care. TRIAL REGISTRATION: The trial was registered at the Clinicaltrials.gov register platform (ID NCT04147039 ) on 31 October 2019.

Functional variants in the sucrase-isomaltase gene associate with increased risk of irritable bowel syndrome.

OBJECTIVE: IBS is a common gut disorder of uncertain pathogenesis. Among other factors, genetics and certain foods are proposed to contribute. Congenital sucrase-isomaltase deficiency (CSID) is a rare genetic form of disaccharide malabsorption characterised by diarrhoea, abdominal pain and bloating, which are features common to IBS. We tested sucrase-isomaltase (SI) gene variants for their potential relevance in IBS. DESIGN: We sequenced SI exons in seven familial cases, and screened four CSID mutations (p.Val557Gly, p.Gly1073Asp, p.Arg1124Ter and p.Phe1745Cys) and a common SI coding polymorphism (p.Val15Phe) in a multicentre cohort of 1887 cases and controls. We studied the effect of the 15Val to 15Phe substitution on SI function in vitro. We analysed p.Val15Phe genotype in relation to IBS status, stool frequency and faecal microbiota composition in 250 individuals from the general population. RESULTS: CSID mutations were more common in patients than asymptomatic controls (p=0.074; OR=1.84) and Exome Aggregation Consortium reference sequenced individuals (p=0.020; OR=1.57). 15Phe was detected in 6/7 sequenced familial cases, and increased IBS risk in case-control and population-based cohorts, with best evidence for diarrhoea phenotypes (combined p=0.00012; OR=1.36). In the population-based sample, 15Phe allele dosage correlated with stool frequency (p=0.026) and Parabacteroides faecal microbiota abundance (p=0.0024). The SI protein with 15Phe exhibited 35% reduced enzymatic activity in vitro compared with 15Val (p<0.05). CONCLUSIONS: SI gene variants coding for disaccharidases with defective or reduced enzymatic activity predispose to IBS. This may help the identification of individuals at risk, and contribute to personalising treatment options in a subset of patients.

Genetics of irritable bowel syndrome.

Irritable bowel syndrome (IBS) is a common condition with a complex and largely unknown etiology. There is no cure, and treatment options are mainly directed to the amelioration of symptoms. IBS causes reduced quality of life and poses considerable repercussions on health and socioeconomic systems. There is a heritable component in IBS, and genetic research is a valuable tool for the identification of causative pathways, which will provide important insight into the pathophysiology. However, although some gene-hunting efforts have been conducted and a few risk genes proposed, IBS genetic research is lagging behind compared to other complex diseases. In this mini-review, we briefly summarize existing genetic studies, discuss the main challenges in IBS genetic research, and propose strategies to overcome these challenges for IBS gene discovery.