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To understand barriers and facilitators to evidence-based prescribing of antibiotics in the outpatient dental setting.
Design:
Semistructured interviews.
Setting:
Outpatient dental setting.
Participants:
Dentists from 40 Veterans’ Health Administration (VA) facilities across the United States.
Methods:
Dentists were identified based on their prescribing patterns and were recruited to participate in a semistructured interview on perceptions toward prescribing. All interviews were recorded, transcribed, and double-coded for analysis, with high reliability between coders. We identified general trends using the theoretical domains framework and mapped overarching themes onto the behavior change wheel to identify prospective interventions that improve evidence-based prescribing.
Results:
In total, 90 dentists participated in our study. The following barriers and facilitators to evidence-based prescribing emerged as impacts on a dentist’s decision making on prescribing an antibiotic: access to resources, social influence of peers and other care providers, clinical judgment, beliefs about consequences, local features of the clinic setting, and beliefs about capabilities.
Conclusions:
Findings from this work reveal the need to increase awareness of up-to-date antibiotic prescribing behaviors in dentistry and may inform the best antimicrobial stewardship interventions to support dentists’ ongoing professional development and improve evidence-based prescribing.
To evaluate opportunities for assessing penicillin allergies among patients presenting to dental clinics.
Design:
Retrospective cross-sectional study.
Setting:
VA dental clinics.
Patients:
Adult patients with a documented penicillin allergy who received an antibiotic from a dentist between January 1, 2015, and December 31, 2018, were included.
Methods:
Chart reviews were completed on random samples of 100 patients who received a noncephalosporin antibiotic and 200 patients who received a cephalosporin. Each allergy was categorized by severity. These categories were used to determine patient eligibility for 3 testing groups based on peer-reviewed algorithms: (1) no testing, (2) skin testing, and (3) oral test-dose challenge. Descriptive and bivariate statistics were used to compare facility and patient demographics first between true penicillin allergy, pseudo penicillin allergy, and missing allergy documentation, and between those who received a cephalosporin and those who did not at the dental visit.
Results:
Overall, 19% lacked documentation of the nature of allergic reaction, 53% were eligible for skin testing, 27% were eligible for an oral test-dose challenge, and 1% were contraindicated from testing. Male patients and African American patients were less likely to receive a cephalosporin.
Conclusions:
Most penicillin-allergic patients in the VA receiving an antibiotic from a dentist are eligible for penicillin skin testing or an oral penicillin challenge. Further research is needed to understand the role of dentists and dental clinics in assessing penicillin allergies.
To determine prophylaxis appropriateness by Veterans’ Affairs (VA) dentists.
Design:
A cross-sectional study of dental visits, 2015–2019.
Methods:
Antibiotics within 7 days before a visit in the absence of an oral infection were included. Appropriate antibiotic prophylaxis was defined as visits with gingival manipulation and further delineated into narrow and broad definitions based on comorbidities. The primary analysis applied a narrow definition of appropriate prophylaxis: cardiac conditions at the highest risk of an adverse outcome from endocarditis. The secondary analysis included a broader definition: cardiac or immunocompromising condition or tooth extractions and/or implants. Multivariable log-linear Poisson generalized estimating equation regression was used to assess the association between covariates and unnecessary prophylaxis prescriptions.
Results:
In total, 358,078 visits were associated with 369,102 antibiotics. The median prescription duration was 7 days (IQR, 7–10); only 6.5% were prescribed for 1 day. With the narrow definition, 15% of prophylaxis prescriptions were appropriate, which increased to 72% with the broader definition. Prophylaxis inconsistent with guidelines increased over time. For the narrow definition, Black (vs White) race, Latine (vs non-Latine) ethnicity, and visits located in the West census region were associated with unnecessary prophylaxis. Variables associated with a lower risk were older age, prosthetic joints, immunocompromising condition, and rural location.
Conclusions:
Of every 6 antibiotic prophylaxis prescriptions, 5 were inconsistent with guidelines. Improving prophylaxis appropriateness and shortening duration may have substantial implications for stewardship. Guidelines should state whether antibiotic prophylaxis is indicated for extractions, implants, and immunocompromised patients.
Among 108 (0.05% of cohort) US veterans with a Clostridioides difficile infection (CDI) within 30 days of a dental antibiotic prescription, 80% of patients received guideline-discordant antibiotics. Half had chronic gastrointestinal illness potentially exacerbating their CDI risk. More efforts are needed to improve antibiotic stewardship.
Copy number variants (CNVs) have been associated with the risk of schizophrenia, autism and intellectual disability. However, little is known about their spectrum of psychopathology in adulthood.
Methods
We investigated the psychiatric phenotypes of adult CNV carriers and compared probands, who were ascertained through clinical genetics services, with carriers who were not. One hundred twenty-four adult participants (age 18–76), each bearing one of 15 rare CNVs, were recruited through a variety of sources including clinical genetics services, charities for carriers of genetic variants, and online advertising. A battery of psychiatric assessments was used to determine psychopathology.
Results
The frequencies of psychopathology were consistently higher for the CNV group compared to general population rates. We found particularly high rates of neurodevelopmental disorders (NDDs) (48%), mood disorders (42%), anxiety disorders (47%) and personality disorders (73%) as well as high rates of psychiatric multimorbidity (median number of diagnoses: 2 in non-probands, 3 in probands). NDDs [odds ratio (OR) = 4.67, 95% confidence interval (CI) 1.32–16.51; p = 0.017) and psychotic disorders (OR = 6.8, 95% CI 1.3–36.3; p = 0.025) occurred significantly more frequently in probands (N = 45; NDD: 39[87%]; psychosis: 8[18%]) than non-probands (N = 79; NDD: 20 [25%]; psychosis: 3[4%]). Participants also had somatic diagnoses pertaining to all organ systems, particularly conotruncal cardiac malformations (in individuals with 22q11.2 deletion syndrome specifically), musculoskeletal, immunological, and endocrine diseases.
Conclusions
Adult CNV carriers had a markedly increased rate of anxiety and personality disorders not previously reported and high rates of psychiatric multimorbidity. Our findings support in-depth psychiatric and medical assessments of carriers of CNVs and the establishment of multidisciplinary clinical services.
In this study, we examined the relationship between polygenic liability for depression and number of stressful life events (SLEs) as risk factors for early-onset depression treated in inpatient, outpatient or emergency room settings at psychiatric hospitals in Denmark.
Methods
Data were drawn from the iPSYCH2012 case-cohort sample, a population-based sample of individuals born in Denmark between 1981 and 2005. The sample included 18 532 individuals who were diagnosed with depression by a psychiatrist by age 31 years, and a comparison group of 20 184 individuals. Information on SLEs was obtained from nationwide registers and operationalized as a time-varying count variable. Hazard ratios and cumulative incidence rates were estimated using Cox regressions.
Results
Risk for depression increased by 35% with each standard deviation increase in polygenic liability (p < 0.0001), and 36% (p < 0.0001) with each additional SLE. There was a small interaction between polygenic liability and SLEs (β = −0.04, p = 0.0009). The probability of being diagnosed with depression in a hospital-based setting between ages 15 and 31 years ranged from 1.5% among males in the lowest quartile of polygenic liability with 0 events by age 15, to 18.8% among females in the highest quartile of polygenic liability with 4+ events by age 15.
Conclusions
These findings suggest that although there is minimal interaction between polygenic liability and SLEs as risk factors for hospital-treated depression, combining information on these two important risk factors could potentially be useful for identifying high-risk individuals.
Lemon Creek Glacier, a temperate valley glacier in the Juneau Icefield of Southeast Alaska, is the site of long running (>60 years) glaciological studies. However, the most recent published estimates of its thickness and subglacial topography come from two ~50 years old sources that are not in agreement and do not account for the effects of years of negative mass balance. We collected a 1-km long active-source seismic line on the upper section of the glacier parallel and near to the centerline of the glacier, roughly straddling the equilibrium-line altitude. We used these data to perform joint reflection-refraction velocity modeling and reflection imaging of the glacier bed. We find that this upper section of Lemon Creek Glacier is as much as 150 m (~65%) thicker than previously suggested with a large overdeepening in an area previously believed to have a uniform thickness. Our results lead us to reinterpret the impact of basal motion on ice flow and have a significant impact on expectations of subglacial hydrology. We suggest that further efforts to develop a whole-glacier model of subglacial topography are necessary to support studies that require accurate models of ice thickness and subglacial topography.
Liver transplantation is the standard of care for end-stage liver disease in children and the vast majority of transplant recipients experience successful outcomes. Better preoperative care, enhanced surgical techniques, and improved immunosuppression strategies have led to the appropriate expectation of good short- and long-term outcomes. Increased indications for liver transplant have led to an ever-increasing number of liver transplant candidates and evaluation of past policies and practices has necessitated changes in allocation policy. Collaboration has also led to better outcomes. Fortunately, continued efforts to expand the use of the donor pool through varied surgical techniques and advanced technology allows more children to benefit from this life-saving and enhancing procedure.
To investigate if food security mediated the impact of a nutrition-sensitive agroecology intervention on women’s depressive symptoms.
Design:
We used annual longitudinal data (four time points) from a cluster-randomised effectiveness trial of a participatory nutrition-sensitive agroecology intervention, the Singida Nutrition and Agroecology Project. Structural equation modelling estimation of total, natural direct and natural indirect effects was used to investigate food security’s role in the intervention’s impact on women’s risk of probable depression (Center for Epidemiologic Studies Depression Scale > 17) across 3 years.
Setting:
Rural Singida, Tanzania.
Participants:
548 food insecure, married, smallholder women farmers with children < 1 year old at baseline.
Results:
At baseline, one-third of the women in each group had probable depression (Control: 32·0 %, Intervention: 31·9 %, P difference = 0·97). The intervention lowered the odds of probable depression by 43 % (OR = 0·57, 95 % CI: 0·43, 0·70). Differences in food insecurity explained approximately 10 percentage points of the effects of the intervention on odds of probable depression (OR = 0·90, 95 % CI: 0·83, 0·95).
Conclusions:
This is the first evidence of the strong, positive effect that lowering food insecurity has on reducing women’s depressive symptoms. Nutrition-sensitive agricultural interventions can have broader impacts than previously demonstrated, i.e. improvements in mental health; changes in food security play an important causal role in this pathway. As such, these data suggest participatory nutrition-sensitive agroecology interventions have the potential to be an accessible method of improving women’s well-being in farming communities.
United States dentists prescribe 10% of all outpatient antibiotics. Assessing appropriateness of antibiotic prescribing has been challenging due to a lack of guidelines for oral infections. In 2019, the American Dental Association (ADA) published clinical practice guidelines (CPG) on the management of acute oral infections. Our objective was to describe baseline national antibiotic prescribing for acute oral infections prior to the release of the ADA CPG and to identify patient-level variables associated with an antibiotic prescription.
Design:
Cross-sectional analysis.
Methods:
We performed an analysis of national VA data from January 1, 2017, to December 31, 2017. We identified cases of acute oral infections using International Classification of Disease, Tenth Revision, Clinical Modification (ICD-10-CM) codes. Antibiotics prescribed by a dentist within ±7 days of a visit were included. Multivariable logistic regression identified patient-level variables associated with an antibiotic prescription.
Results:
Of the 470,039 VA dental visits with oral infections coded, 12% of patient visits with irreversible pulpitis, 17% with apical periodontitis, and 28% with acute apical abscess received antibiotics. Although the median days’ supply was 7, prolonged use of antibiotics was frequent (≥8 days, 42%–49%). Patients with high-risk cardiac conditions, prosthetic joints, and endodontic, implant, and oral and maxillofacial surgery dental procedures were more likely to receive antibiotics.
Conclusions:
Most treatments of irreversible pulpitis and apical periodontitis cases were concordant with new ADA guidelines. However, in cases where antibiotics were prescribed, prolonged antibiotic courses >7 days were frequent. These findings demonstrate opportunities for the new ADA guidelines to standardize and improve dental prescribing practices.
To characterize postextraction antibiotic prescribing patterns, predictors for antibiotic prescribing and the incidence of and risk factors for postextraction oral infection.
Design:
Retrospective analysis of a random sample of veterans who received tooth extractions from January 1, 2017 through December 31, 2017.
Setting:
VA dental clinics.
Patients:
Overall, 69,610 patients met inclusion criteria, of whom 404 were randomly selected for inclusion. Adjunctive antibiotics were prescribed to 154 patients (38.1%).
Intervention:
Patients who received or did not receive an antibiotic were compared for the occurrence of postextraction infection as documented in the electronic health record. Multivariable logistic regression was performed to identify factors associated with antibiotic receipt.
Results:
There was no difference in the frequency of postextraction oral infection identified among patients who did and did not receive antibiotics (4.5% vs 3.2%; P = .59). Risk factors for postextraction infection could not be identified due to the low frequency of this outcome. Patients who received antibiotics were more likely to have a greater number of teeth extracted (aOR, 1.10; 95% CI, 1.03–1.18), documentation of acute infection at time of extraction (aOR, 3.02; 95% CI, 1.57–5.82), molar extraction (aOR, 1.78; 95% CI, 1.10–2.86) and extraction performed by an oral maxillofacial surgeon (aOR, 2.29; 95% CI, 1.44–3.58) or specialty dentist (aOR, 5.77; 95% CI, 2.05–16.19).
Conclusion:
Infectious complications occurred at a low incidence among veterans undergoing tooth extraction who did and did not receive postextraction antibiotics. These results suggest that antibiotics have a limited role in preventing postprocedural infection; however, future studies are necessary to more clearly define the role of antibiotics for this indication.
This study reports on the changes in stress, anxiety, and depressive symptoms of subscribers after 3 months using Text4Hope, a supportive text messaging program designed to provide support during the pandemic.
Methods:
Standardized self-report measures were used to evaluate perceived stress (measured with the Perceived Stress Scale-10 [PSS-10]), anxiety (measured with the General Anxiety Disorder Scale 7 [GAD-7]), and depressive symptoms (measured with the Patient Health Questionnaire [PHQ-9]), at baseline and 3rd month (n = 373).
Results:
After 3 months of using Text4Hope, subscribers’ self-reports revealed significant (p< 0.001) mean score reductions compared with baseline on: the GAD-7 by 22.7%, PHQ-9 by 10.3%, and PSS-10 scores by 5.7%. Reductions in inferred prevalence rates for moderate to high symptoms were also observed, with anxiety demonstrating the largest reduction (15.7%).
Conclusions:
Observed Text4Hope-related reductions in psychological distress during COVID-19 indicate that Text4Hope is an effective, convenient, and accessible means of implementing a population-level psychological intervention.
Associations between prenatal maternal psychological distress and offspring developmental outcomes are well documented, yet relatively little research has examined links between maternal distress and development in utero, prior to postpartum influences. Fetal heart rate (FHR) parameters are established indices of central and autonomic nervous system maturation and function which demonstrate continuity with postnatal outcomes. This prospective, longitudinal study of 149 maternal–fetal pairs evaluated associations between prenatal maternal distress, FHR parameters, and dimensions of infant temperament. Women reported their symptoms of psychological distress at five prenatal visits, and FHR monitoring was conducted at the last three visits. Maternal report of infant temperament was collected at 3 and 6 months of age. Exposure to elevated prenatal maternal psychological distress was associated with higher late-gestation resting mean FHR (FHRM) among female but not male fetuses. Higher late-gestation FHRM was associated with lower infant orienting/regulation and with higher infant negative affectivity, and these associations did not differ by infant sex. A path analysis identified higher FHRM as one pathway by which elevated prenatal maternal distress was associated with lower orienting/regulation among female infants. Findings suggest that, for females, elevated maternal distress alters fetal development, with implications for postnatal function. Results also support the notion that, for both sexes, individual differences in regulation emerge prenatally and are maintained into infancy. Collectively, these findings underscore the utility of direct assessment of development in utero when examining if prenatal experiences are carried forward into postnatal life.
Prenatal diethylstilbestrol (DES) exposure is associated with increased risk of hormonally mediated cancers and other medical conditions. We evaluated the association between DES and risk of pancreatic cancer and pancreatic disorders, type 2 diabetes, and gallbladder disease, which may be involved with this malignancy. Our analyses used follow-up data from the US National Cancer Institute DES Combined Cohort Study. Cox proportional hazards models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) adjusted for age, sex, cohort, body mass index, smoking, and alcohol for the association between prenatal DES exposure and type 2 diabetes, gallbladder disease (mainly cholelithiasis), pancreatic disorders (mainly pancreatitis), and pancreatic cancer among 5667 exposed and 3315 unexposed individuals followed from 1990 to 2017. Standardized incidence rate (SIR) ratios for pancreatic cancer were based on age-, race-, and calendar year-specific general population cancer incidence rates. In women and men combined, the hazards for total pancreatic disorders and pancreatitis were greater in the prenatally DES exposed than the unexposed (HR = 11, 95% CI 2.6–51 and HR = 7.0, 95% CI 1.5–33, respectively). DES was not associated overall with gallbladder disease (HR = 1.2, 95% CI 0.88–1.5) or diabetes (HR = 1.1, 95% CI 0.9–1.2). In women, but not in men, DES exposure was associated with increased risk of pancreatic cancer compared with the unexposed (HR: 4.1, 95% CI 0.84–20) or general population (SIR: 1.9, 95% CI 1.0–3.2). Prenatal DES exposure may increase the risk of pancreatic disorders, including pancreatitis in women and men. The data suggested elevated pancreatic cancer risk in DES-exposed women, but not in exposed men.
Parents play an important role in creating home language environments that promote language development. A nonequivalent group design was used to evaluate the effectiveness of a community-based implementation of LENA Start™, a parent-training program aimed at increasing the quantity of adult words (AWC) and conversational turns (CT). Parent-child dyads participated in LENA Start™ (n = 39) or a generic parent education program (n = 17). Overall, attendance and engagement in the LENA StartTM program were high: 72% of participants met criteria to graduate from the program. Within-subject gains were positive for LENA Start™ families. Comparison families declined on these measures. However, both effects were non-significant. Between-group analyses revealed small to medium-sized effects favoring LENA Start™ and these were significant for child vocalizations (CV) and CT but not AWC. These results provide preliminary evidence that programs like LENA StartTM can be embedded in community-based settings to promote quality parent-child language interactions.
A number of genomic conditions caused by copy number variants (CNVs) are associated with a high risk of neurodevelopmental and psychiatric disorders (ND-CNVs). Although these patients also tend to have cognitive impairments, few studies have investigated the range of emotion and behaviour problems in young people with ND-CNVs using measures that are suitable for those with learning difficulties.
Methods
A total of 322 young people with 13 ND-CNVs across eight loci (mean age: 9.79 years, range: 6.02–17.91, 66.5% male) took part in the study. Primary carers completed the Developmental Behaviour Checklist (DBC).
Results
Of the total, 69% of individuals with an ND-CNV screened positive for clinically significant difficulties. Young people from families with higher incomes (OR = 0.71, CI = 0.55–0.91, p = .008) were less likely to screen positive. The rate of difficulties differed depending on ND-CNV genotype (χ2 = 39.99, p < 0.001), with the lowest rate in young people with 22q11.2 deletion (45.7%) and the highest in those with 1q21.1 deletion (93.8%). Specific patterns of strengths and weaknesses were found for different ND-CNV genotypes. However, ND-CNV genotype explained no more than 9–16% of the variance, depending on DBC subdomain.
Conclusions
Emotion and behaviour problems are common in young people with ND-CNVs. The ND-CNV specific patterns we find can provide a basis for more tailored support. More research is needed to better understand the variation in emotion and behaviour problems not accounted for by genotype.
Little is known about who would benefit from Internet-based personalised nutrition (PN) interventions. This study aimed to evaluate the characteristics of participants who achieved greatest improvements (i.e. benefit) in diet, adiposity and biomarkers following an Internet-based PN intervention. Adults (n 1607) from seven European countries were recruited into a 6-month, randomised controlled trial (Food4Me) and randomised to receive conventional dietary advice (control) or PN advice. Information on dietary intake, adiposity, physical activity (PA), blood biomarkers and participant characteristics was collected at baseline and month 6. Benefit from the intervention was defined as ≥5 % change in the primary outcome (Healthy Eating Index) and secondary outcomes (waist circumference and BMI, PA, sedentary time and plasma concentrations of cholesterol, carotenoids and omega-3 index) at month 6. For our primary outcome, benefit from the intervention was greater in older participants, women and participants with lower HEI scores at baseline. Benefit was greater for individuals reporting greater self-efficacy for ‘sticking to healthful foods’ and who ‘felt weird if [they] didn’t eat healthily’. Participants benefited more if they reported wanting to improve their health and well-being. The characteristics of individuals benefiting did not differ by other demographic, health-related, anthropometric or genotypic characteristics. Findings were similar for secondary outcomes. These findings have implications for the design of more effective future PN intervention studies and for tailored nutritional advice in public health and clinical settings.
Iodine is an essential micronutrient and an integral part of the thyroid hormones. In women of childbearing age, the estimated average iodine requirement is 95 μg/day and the recommended daily intake is 150 μg/day. While severe iodine deficiency poses reproductive risks, including infertility and abortions, the potential impact of mild-to-moderate iodine deficiency on subfecundity is unknown.
We examined whether iodine intake was associated with risk of subfecundity (i.e. > 12 months trying to get pregnant) in a large cohort of mild-to-moderately iodine deficient women.
Women enrolled in the Norwegian Mother and Child Cohort Study in gestational week 15 were asked to report whether the pregnancy was planned and how many months the couple had sexual relations without any contraception before getting pregnant. Information about time to pregnancy, maternal characteristics and iodine intake was available for 56,416 planned pregnancies. The median (interquartile range) time to pregnancy was 1.5 (0.5–6.0) months and the prevalence of subfecundity was 10.8%). We used iodine intake assessed by a validated food frequency questionnaire administered in pregnancy as a proxy for long-term (pre-pregnancy) iodine intake. We used logistic regression to estimate the association between iodine intake and subfecundity, using flexible modelling with restricted cubic splines, and adjusted for maternal age, BMI, parity, education, smoking status, energy intake and fiber intake. The median calculated iodine intake was 121 μg/day and the median urinary iodine concentration in a subsample of n = 2795 women was 69 μg/L.
The prevalence of subfecundity was lowest for iodine intakes ~100 μg/day and increased at lower intakes (p overall = 0.005). Compared to an intake of 100 μg/day (reference), intakes ~75 μg/day was associated with 5% (95%CI: 1%, 9%) higher prevalence and intakes ~50 μg/day with 14% (95%CI: 4%, 26%) higher prevalence. Use of dietary supplements was recorded only for the last 6 months prior to conception and women were included in the analysis regardless of their reported supplement use. In a sensitivity analysis, we excluding women who reported iodine-containing supplement use in the period 26–9 weeks before conception and the result remained unchanged. We also modelled time to pregnancy by Cox regression, and the result was consistent with the result for subfecundity.
The only good dietary sources of iodine in Norway are milk and white fish, and many women of fertile age have low intakes of these food items. This study shows that low habitual iodine intake may be a risk factor for subfecundity.
Iodine is essential in foetal development through being an integral part of the thyroid hormones. Severe iodine deficiency is associated with foetal growth restriction and preterm delivery. Less is known about the potential impact of mild-to-moderate iodine deficiency on these outcomes.
The aim of this study was to investigate whether maternal iodine intake in pregnancy was associated with birth weight (BW) z-score (i.e. BW adjusted for gestational length and sex) and preterm delivery (before week 37).
The study population included 77,995 singleton pregnancies from The Norwegian Mother and Child Cohort Study recruited in gestational week 15 in the period 2002–2008. Habitual iodine intake was calculated from a validated food frequency questionnaire covering the first half of pregnancy. Use of supplements was reported in questionnaires. Urinary iodine concentration (UIC) was measured in gestational week 18 in a subsample of n = 2795 women. Median iodine intake from food was 121 μg/day and median UIC was 69 μg/L. Median UIC < 150 μg/L is considered insufficient in pregnant women. Median birthweight was 3610 g and 5.0% were born before gestational week 37. Associations were modelled flexibly by use of restricted cubic splines, and adjusted for age, parity, pre-pregnancy BMI, education, smoking in pregnancy, energy intake, and fibre intake.
In non-users of iodine-containing supplements (n = 48,958), a low habitual iodine intake from food (lower than about 150 μg/day) was associated with a lower mean BW z-score (p < 0.001). Compared to an intake of 150 μg/day (reference), mean z-score was 0.04 SD lower at 100 μg/day and 0.12 SD lower at 75 μg/day. Results were similar when using UIC as the exposure (n = 2795, p = 0.017). Any use of iodine containing supplements in pregnancy was associated with 0.03 (95% CI: 0.01, 0.04) SD increase in BW z-score compared to no use (n = 77,949, p < 0.001).
A low habitual iodine intake from food (lower than about 100 μg/day) was associated with increased risk of preterm delivery (p = 0.003). Compared to an intake of 100 μg/day (reference), 75 μg/day was associated with 10% increased risk, and 50 μg/day with 28% increased risk. Use of an iodine-containing supplement was not associated with the risk of preterm delivery (OR: 0.97 (95%CI: 0.91, 1.04, p = 0.42)).
Inadequate iodine intake is prevalent in women of childbearing age in otherwise well-nourished populations. Our results indicate that mild-to-moderate iodine deficiency in pregnancy is associated with restricted foetal growth and increased risk of preterm delivery.