Date of birth in the occurrence of inflammatory bowel disease

Early life exposures and the risk of inflammatory bowel disease: Systematic review and meta-analyses

BACKGROUND

Early life exposures impact immune system development and therefore the risk of immune-mediated diseases, including inflammatory bowel disease (IBD). We systematically reviewed the impact of pre-, peri‑, and postnatal exposures up to the age of five years on subsequent IBD diagnosis.

METHODS

We identified case-control and cohort studies reporting on the association between early life environmental factors and Crohn's disease (CD), ulcerative colitis (UC), or IBD overall. Databases were search from their inception until May 24th, 2019 until July 14th, 2020. We conducted meta-analyses for quantitative review of relevant risk factors that were comparable across studies and qualitative synthesis of the literature for a wide range of early life exposures, including maternal health and exposures during pregnancy, perinatal factors, birth month and related-factors, breastfeeding, hygiene-related factors and social factors, immigration, antibiotics, offspring health, including infections, and passive smoking. PROSPERO registration: CRD42019134980.

FINDINGS

Prenatal exposure to antibiotics (OR 1.8; 95% CI 1.2-2.5) and tobacco smoke (OR 1.5; 95% CI 1.2-1.9), and early life otitis media (OR 2.1; 95% CI 1.2-3.6) were associated with IBD. There was a trend towards an association between exposure to antibiotics in infancy and IBD (OR: 1.7, 95% CI 0.97, 2.9), supported by positive data on population-based data. Breastfeeding was protective against IBD. Other early life risk factors had no association with IBD, but data were limited and heterogenous.

INTERPRETATION

Early life is an important period of susceptibility for IBD development later in life. Tobacco smoke, infections and antibiotics were associated positively, and breastfeeding was associated negatively with IBD. Our findings offer an opportunity to develop primary prevention strategies.

FUNDING

This study did not receive any funding.

Prenatal and Early Life Exposure to the Danish Mandatory Vitamin D Fortification Policy Might Prevent Inflammatory Bowel Disease Later in Life: A Societal Experiment

This register-based national cohort study of 206,900 individuals investigated whether prenatal exposure to small extra doses of vitamin D from fortified margarine prevented inflammatory bowel disease (IBD) later in life; whether the risk of IBD varied according to month or season of birth; and finally, whether there was an interaction between exposure to extra D vitamin and month or season of birth. Fortification of margarine with vitamin D was mandatory in Denmark from the mid-1930s until 1st June 1985, when it was abolished. Two entire birth cohorts, each including two years, were defined: one exposed and one unexposed to the fortification policy for the entire gestation. All individuals were followed for 30 years from the day of birth for an IBD diagnosis in Danish hospital registers. Logistic regression analyses were used to estimate odds ratios (OR) and 95% confidence intervals (CI). Odds for IBD was lower among those exposed to extra D vitamin compared to those unexposed, OR = 0.87 (95% CI: 0.79; 0.95). No association with month or season of birth was found. However, estimates suggested that particularly children born during autumn may have benefitted from the effect of small extra doses of vitamin D. This is, to our knowledge, the first study to explore if prenatal exposure to vitamin D from fortification influenced the risk of IBD. Our results suggest that prenatal exposure to small amounts of extra vitamin D from food fortification may protect against the development of IBD before 30 years of age.

Seasonality of month of birth in children and adolescents with autoimmune thyroiditis: a continuing conundrum

Background The aim of this study was to analyze the seasonal birth month pattern in young patients with autoimmune thyroiditis and compare it with youth controls. Methods Medical records of a total of 298 children and adolescents of Greek origin, with a diagnosis of Hashimoto thyroiditis (HT) before the age of 21 years that were born from 1987 to 2010 were retrospectively reviewed. In addition, 298 consecutive subjects that were born from 1988 to 2012 and evaluated in a tertiary unit for any reason, served as controls, provided that they had no personal or family history of thyroid or any other autoimmune disease. Results Significant differences were found between children and adolescents with HT and healthy controls in the yearly pattern of month of birth distribution (p=0.029). During month-by-month analysis, it was shown that the highest and lowest predispositions to HT were among those born in spring (March) (odds ratio [OR] 2.34, p=0.005), and autumn (November) (OR 0.49, p=0.035), respectively. A binary logistic regression model also revealed that season of birth and sex were the only factors that remained related to HT disease, even after adjustment for confounding factors such as year of birth and age (p<0.001, Nagelkerke r-square 0.151). Conclusions This study suggests that the effect of certain seasonal factors during fetal development, reflected by the seasonal differences in birth pattern, in children and adolescents with autoimmune thyroiditis could contribute to long-term programming of an autoimmune response against the thyroid gland. Further studies are needed to demonstrate a clear cause and effect relationship between month of birth and HT.

Low Sun Exposure and Vitamin D Deficiency as Risk Factors for Inflammatory Bowel Disease, With a Focus on Childhood Onset

The incidence and prevalence of inflammatory bowel disease (IBD) are increasing worldwide. Some ecological studies show increasing incidence with increasing latitude. Ambient ultraviolet radiation varies inversely with latitude, and sun exposure of the skin is a major source of vitamin D. Vitamin D deficiency is common in patients with IBD. Sun exposure and vitamin D have immune effects that could plausibly reduce, or be protective for, IBD. One quarter of new IBD cases are diagnosed in childhood or adolescence, but most research is for adult-onset IBD. Here, we review the evidence for low sun exposure and/or vitamin D deficiency as risk factors for IBD, focusing where possible on pediatric IBD, where effects of environmental exposures may be clearer. The literature provides some evidence of a latitude gradient of IBD incidence, and evidence for seasonal patterns of timing of birth or disease onset is inconsistent. High prevalence of vitamin D deficiency occurs in people with IBD, but cannot be interpreted as being a causal risk factor. Evidence of vitamin D supplementation affecting disease activity is limited. Further research on predisease sun exposure and well-designed supplementation studies are required to elucidate whether these potentially modifiable exposures are indeed risk factors for IBD.

Academic Stress May Contribute to the Onset of Pediatric Inflammatory Bowel Diseases

It is currently unclear whether seasonality affects the onset of inflammatory bowel diseases (IBDs: Crohn disease and ulcerative colitis) in children. Here, we examined the records of pediatric patients with IBD diagnosed between 2009 and 2015 in a discovery cohort of 169 cases and a validation cohort of 122 subjects, where the month of symptoms onset could be determined. No seasonal patterns could be identified in respect to conception, birth, and disease onset. An annual rhythm of symptomatic onset, however, correlating with academic semesters was identified. IBD symptoms in the discovery cohort presented significantly more (P = 0.0218) during 5 months including the initiation (August, September, January) and the termination of academic semesters (December, May) compared to any other 5 months of the year. This observation was validated in the independent cohort (P < 0.0001). Our findings imply that academic stress may contribute to disease onset in pediatric IBD, which may improve timely diagnosis.

Perinatal vitamin D levels are not associated with later risk of developing pediatric-onset inflammatory bowel disease: a Danish case-cohort study

Objective Basic and epidemiologic studies on inflammatory bowel disease (IBD) have suggested an association between vitamin D and IBD risk. Though, the literature on IBD - especially pediatric-onset IBD - and vitamin D is still in its cradle. We therefore wanted to examine if levels of 25(OH)D at birth were associated with increased risk of developing pediatric-onset IBD. Material and methods A case-cohort study composed of cases diagnosed with Crohn's disease, ulcerative colitis or indeterminate/unclassified colitis and healthy controls. Cases and controls were matched on date of birth and were born in the period 1981-2004. Cases were diagnosed before the age of 18 years. The concentration of 25(OH)D was assessed from neonatal dried blood spots using a highly sensitive liquid chromatography tandem mass spectrometry. Odds ratios (OR) were calculated using conditional logistic regression and two-way ANOVA were used to test for season and birth year 25(OH)D variations. A total of 384 matched pairs were included in the statistical analyses. Results No significant association were found between levels of 25(OH)D and IBD risk in the adjusted model (OR [95% CI] (per 25 nmol/L increase), 1.12 [0.88; 1.42], p = 0.35). 25(OH)D levels were found to fluctuate significantly with season (p < 0.001) and year (p < 0.001). Median/Q1-Q3 values for 25(OH)D were 27.1/16.5-39.5 nmol/L for cases and 25.7/16.1-39.4 nmol/L for controls. Conclusion Our study do not suggest that a window of vulnerability exist around time of birth in regards to 25(OH)D levels and later pediatric-onset IBD risk.

Impact of the birth's season on the development of celiac disease in Italy

Celiac disease (CD) is an immune-mediated systemic disorder induced by a trigger factor in genetically susceptible individuals. There is emerging evidence about the impact of the month of birth on the development of several autoimmune diseases. Our aim was to investigate whether, in Italian CD children, the season of birth is associated with development of CD later in life. We report a survey conducted at two Italian referral centers for CD in Rome and Bari. The CD database was created to enable retrospective examination of the data of all the consecutive patients, born between 2003 and 2010, who had received a diagnosis of CD. This CD patient group comprising 596 children was compared with a reference group that included all subjects born in the same period and in the same cities (439,990 controls). Overall, there was a summer birth preponderance in CD patients compared to controls (28.2 % of CD patients vs 23.0 % of the control population; OR 1.315; 95 % CI 1.100 to 1.572). Stratifying the caseload by gender and age, the summer birth preponderance was maintained for females (28.6 % CD females vs 22.6 % control females; OR 1.368; 95 % CI 1.069 to 1.750).

CONCLUSIONS

our survey confirms that in Italy, children born in summer are at higher risk to develop CD than subjects born in other seasons. The identification of a responsible seasonal factor or factors, such as timing of the first introduction of gluten and/or acute viral gastrointestinal infections, would be very important for disease prevention strategies.

WHAT IS KNOWN

• Environmental factors could be involved in the pathogenesis of CD. • Data about the impact of season of birth on CD development is so far derived from North American, Northern European and Israeli surveys.

WHAT IS NEW

• This is the first study in Southern Europe to find a relationship between season of birth (summer) and development of CD. • Summer-born infants are introduced to complementary feeding (gluten) in winter, when the rotavirus infection is at its highest peak; this may be the link between season of birth and development of CD.

Low vitamin D status throughout life results in an inflammatory prone status but does not alter bone mineral or strength in healthy 3-month-old CD-1 male mice

SCOPE

The aim of this study was to assess if exposure to different levels of dietary vitamin D pre- and postweaning impacts the intestinal-bone axis.

METHODS AND RESULTS

Female CD1 mice were exposed to high (5000 IU vitamin D3 /kg diet, H) or low (25 IU vitamin D3 /kg diet, L) vitamin D diet (modified AIN-93G) during pregnancy and lactation. At weaning (postnatal day 21), a subset of the male offspring was sacrificed and another subset was assigned to receive their dams' respective diet (HH and LL) or the other diet (HL and LH) until sacrifice at 3 months of age. Lower level of vitamin D resulted in reduced vitamin D receptor and increased expression of pro-inflammatory genes in the colon at 3 months, lower numbers of colonic Bacteroides/Prevotella at postnatal day 21 and higher serum LPS concentration at adulthood. There was a programming effect of vitamin D on LPS levels. Mineral content, density, and strength of femurs and vertebrae were not affected.

CONCLUSION

Our findings suggest that low vitamin D exposure results in an inflammatory-prone status that may contribute to or be a risk factor for several diseases including inflammatory bowel disease, obesity, diabetes, and cardiovascular diseases.

Association between spring season of birth and Crohn's disease

BACKGROUND & AIMS

As for many complex diseases, the incidence of inflammatory bowel disease (IBD) is higher among individuals born during certain seasons. This difference could arise from seasonal variations in many factors, including exposure to sunlight, antibiotics, or infectious agents. We investigated the relationship between season of birth, early childhood exposure to antibiotics, and incidence of IBD.

METHODS

We performed a nested case-control analysis using data from the University of Manitoba inflammatory bowel disease epidemiology database. We compared seasons of birth among 11,145 individuals with IBD (cases) and 108,633 controls using conditional logistic regression models. We collected data on use of antibiotics in the first year of life for cases and controls from the Manitoba Drug Program Information Network-a comprehensive database of all prescriptions given to residents of Manitoba since 1995.

RESULTS

Approximately 27.0% of cases were born from April through June, compared with 25.6% of controls (odds ratio, 1.07; 95% confidence interval, 1.02-1.12; P = .002). Comparisons made by sex (male vs female) and type of IBD (ulcerative colitis vs Crohn's disease) showed statistical significance only for men with Crohn's disease (odds ratio, 1.13; 95% confidence interval, 1.03-1.25; P = .009). At ages 6 months and older, cases and controls born from April through June received a significantly greater number of prescriptions for antibiotics than cases and controls born in other months.

CONCLUSIONS

Men with Crohn's disease are more likely to have been born in the months of April through June.

Seasonal variation in months of birth and symptom flares in Korean patients with inflammatory bowel disease

Background/Aims

Seasonal variation may influence the development and exacerbation of inflammatory bowel disease (IBD). However, most epidemiologic studies on this topic have been conducted in Western countries. The purpose of this study was to determine whether birth dates and symptom flares follow a seasonal pattern in Korean patients with IBD.

Methods

Patients with a diagnosis of IBD established between January 2003 and December 2010 were investigated at six university hospitals in Korea. The expected births and flares, with a uniform distribution during the year and considering differences in the number of days in the months of 1 year, were calculated.

Results

A total of 411 patients with ulcerative colitis (UC) and 316 patients with Crohn disease (CD) were included in the study. Birth during the winter period, and especially in January and February, was associated with an increased risk of IBD, especially in UC patients. The symptom flares of CD patients occurred most frequently in the spring, with a nadir in the autumn. However, no disease flare seasonality was noted for UC patients.

Conclusions

Our data suggest that seasonally varying environmental factors during pregnancy and the postpartum period are associated with a susceptibility to IBD later in life and that exacerbations of CD are influenced by seasonal factors.

Month of birth, vitamin D and risk of immune-mediated disease: a case control study

BACKGROUND

A season of birth effect in immune-mediated diseases (ID) such as multiple sclerosis and type 1 diabetes has been consistently reported. We aimed to investigate whether season of birth influences the risk of rheumatoid arthritis, Crohn's disease, ulcerative colitis and systemic lupus erythematosus in addition to multiple sclerosis, and to explore the correlation between the risk of ID and predicted ultraviolet B (UVB) light exposure and vitamin D status during gestation.

METHODS

The monthly distribution of births of patients with ID from the UK (n = 115,172) was compared to that of the general population using the Cosinor test. Predicted UVB radiation and vitamin D status in different time windows during pregnancy were calculated for each month of birth and correlated with risk of ID using the Spearman's correlation coefficient.

RESULTS

The distributions of ID births significantly differed from that of the general population (P = 5e-12) with a peak in April (odds ratio = 1.045, 95% confidence interval = 1.024, 1.067, P < 0.0001) and a trough in October (odds ratio = 0.945, 95% confidence interval = 0.925, 0.966, P < 0.0001). Stratification by disease subtype showed seasonality in all ID but Crohn's disease. The risk of ID was inversely correlated with predicted second trimester UVB exposure (Spearman's rho = -0.49, P = 0.00005) and third trimester vitamin D status (Spearman's rho = -0.44, P = 0.0003).

CONCLUSIONS

The risk of different ID in the UK is significantly influenced by the season of birth, suggesting the presence of a shared seasonal risk factor or factors predisposing to ID. Gestational UVB and vitamin D exposure may be implicated in the aetiology of ID.

Season of birth is significantly associated with the risk of completed suicide

BACKGROUND

Previous studies have provided somewhat inconsistent results about the effects of season of birth on the risk of suicidal behavior. Therefore, we decided to investigate this question in a large sample of suicide completers.

METHODS

We determined the season of birth-associated risk of completed suicide between the years 1970 and 2008 among all individuals who were born in the area of today's Hungary between 1930 and 1939, 1941 and 1942, and 1944 and 1969.

RESULTS

The final sample of participants included around six and a half million people. About 80,000 completed suicides occurred among participants during the period investigated (the number of suicide completers in our study greatly exceeds the number of suicide completers in any previous studies). A significantly (p < .05) elevated risk of completed suicide was found among those individuals who were born in the high-risk period (spring and summer). Quantitatively, the biggest increase (7.6% [95% confidence interval: 5.4-9.9]) in suicide risk was detected among those who were born in July compared with the average risk of suicide in the population investigated. The associations between season of birth and the risk of completed suicide were stronger among male subjects than among female subjects and among those who committed suicide using violent methods than among those who chose nonviolent methods.

CONCLUSIONS

Our results from a large sample of suicide completers from Hungary--a country with one of the highest suicide rates in the world over the last century--strongly support the concept that the season of birth is significantly associated with the risk of completed suicide.