Psoriasis and mental health in adolescents: A cross-sectional study within the Danish National Birth Cohort.

BACKGROUND: Psoriasis is a chronic skin disease associated with lower quality of life and higher risk of anxiety and depression in adults. We investigate whether adolescents with psoriasis also experience poorer mental health than their peers. METHODS: In this cross-sectional study, we included questionnaire data on psoriasis and mental health from the 18-year follow-up of the Danish National Birth Cohort. We estimated odds ratios (OR) and 95 % confidence intervals (CI) using a logistic regression with inverse probability weighting to account for potential selection bias, adjusted for potential confounders identified a priori. We estimated associations between self-reported psoriasis and multiple aspects of mental health (self-rated health, life satisfaction, mental well-being, loneliness, overall and internalizing behavioral difficulties, depressive symptoms, and anxiety symptoms). In sensitivity analyses, we examined doctor-diagnosed psoriasis and psoriasis with and without joint pain. RESULTS: Of the 44,838 included in this study, 1147 (2.6 %) reported psoriasis. Adolescents with psoriasis had a higher risk of nearly all outcomes, including depressive symptoms (OR 1.38; 1.19-1.58) and panic/agoraphobia among both males (OR 1.72; 1.33-2.19) and females (OR 1.60; 1.33-1.92). Associations attenuated when restricted to doctor-diagnosed psoriasis. Associations with poor mental health were mainly observed for adolescents with psoriasis also reporting joint pain. LIMITATIONS: We could not establish temporality and lacked data on joint pain in referents. CONCLUSION: Psoriasis is associated with poor mental health in adolescents. This appears to be driven by adolescents with psoriasis also reporting joint pain and is less evident in those with a doctor-confirmed diagnosis.

Residential exposure to mold, dampness, and indoor air pollution and risk of respiratory tract infections: a study among children ages 11 and 12 in the Danish National Birth Cohort.

BACKGROUND: The burden of respiratory tract infections (RTIs) is high in childhood. Several residential exposures may affect relative rates. OBJECTIVES: To determine risk of RTIs in children ages 11 and 12 by residential exposures. METHODS: We included children in the Danish National Birth Cohort (DNBC) at ages 11 and 12. We estimated incidence risk ratios (IRR) and 95% confidence intervals (CI) for counts of RTIs within the last year by exposure to mold/dampness, gas stove usage, summer and winter candle-burning, fireplace usage, cats and dogs indoors, and farmhouse living. We also estimated IRR and 95% CI for RTIs for predicted scores of four extracted factors ('owned house', 'mold and dampness', 'candles', and 'density') from exploratory factor analyses (EFA). RESULTS: We included 42 720 children with complete data. Mold/dampness was associated with all RTIs (common cold: IRRadj 1.09[1.07, 1.12]; influenza: IRRadj 1.10 [1.05, 1.15]; tonsillitis: IRRadj 1.19 [1.10, 1.28]; conjunctivitis: IRRadj 1.16 [1.02, 1.32]; and doctor-diagnosed pneumonia: IRRadj 1.05 [0.90, 1.21]), as was the EFA factor 'mold/dampness' for several outcomes. Gas stove usage was associated with conjunctivitis (IRRadj 1.25 [1.05, 1.49]) and with doctor-diagnosed pneumonia (IRRadj 1.14 [0.93, 1.39]). Candle-burning during summer, but not winter, was associated with several RTIs, for tonsillitis in a dose-dependent fashion (increasing weekly frequencies vs. none: [IRRadj 1.06 [0.98, 1.14], IRRadj 1.16 [1.04, 1.30], IRRadj 1.23 [1.06, 1.43], IRRadj 1.29 [1.00, 1.67], and IRRadj 1.41 [1.12, 1.78]). CONCLUSION: Residential exposures, in particular to mold and dampness and to a lesser degree to indoor combustion sources, are related to the occurrence of RTIs in children.

Exposure to different residential indoor characteristics during childhood and asthma in adolescence: a latent class analysis of the Danish National Birth Cohort.

BACKGROUND: Many residential indoor environments may have an impact on children's respiratory health. OBJECTIVES: The aims of this study were to identify latent classes of children from the Danish National Birth Cohort (DNBC) who share similar patterns of exposure to indoor home characteristics, and to examine the association between membership in the latent classes and asthma in adolescence. METHODS: We included data on residential indoor characteristics of offspring from the DNBC whose mothers had responded to the child's 11-year follow-up and who had data on asthma from the 18-year follow-up. Number of classes and associations were estimated using latent class analysis. To account for sample selection, we applied inverse probability weighting. RESULTS: Our final model included five latent classes. The probability of current asthma at 18 years was highest among individuals in class one with higher clustering on household dampness (9, 95%CI 0.06-0.13). Individuals in class four (with higher clustering on pets ownership and living in a farm) had a lower risk of current asthma at age 18 compared to individuals in class one (with higher clustering on household dampness) (OR 0.53 (95%CI 0.32-0.88), p = .01). CONCLUSION: Our findings suggest that, in a high-income country such as Denmark, groups of adolescents growing up in homes with mold and moisture during mid-childhood might be at increased risk of current asthma at age 18. Adolescents who grew-up in a farmhouse and who were exposed to pets seem less likely to suffer from asthma by age 18.

Exposure to residential mold and dampness and the associations with respiratory tract infections and symptoms thereof in children in high income countries: A systematic review and meta-analyses of epidemiological studies.

BACKGROUND: Multiple reviews have been conducted on the associations between residential mold and dampness and respiratory outcomes in children, with few specifically investigating respiratory tract infections (RTIs). OBJECTIVE: We aimed to review and synthesize the available epidemiological literature on mold and dampness and risk of RTIs and respiratory symptoms compatible with RTIs in children living in high-income countries. METHOD: We performed a systematic search of literature available from MEDLINE, Embase, and Web of Science for observational studies. We conducted meta-analyses using two-level random effects (RE) and multi-level random effects (ML) models for contrasts of three exposure and three outcome categories, including multiple estimates reported by single studies. We report central estimates for pooled odds ratios (OR) and 95 % confidence intervals (CI).We conducted a risk of bias assessment using the Joanna Briggs Initiative (JBI) checklists for cross-sectional, case-control, and cohort studies. We additionally report on cumulative meta-analyses, leave-one-out analyses of single estimates, subgroup analyses by study quality and study design and inclusion of all effect estimates. RESULTS: Of the 932 studies initially screened by title and abstract, we included 30 studies with 267 effect estimates that met the inclusion criteria. Most were cross-sectional (n = 22), with fewer cohort (n = 5) and case-control (n = 3) studies. Most of the studies were according to the bias assessment of poor or fair quality (n = 24). The main meta-analyses generally provided similar results regardless of statistical model and central estimates ranged from OR 1.28 (95 % CI; 1.08, 1.53) for dampness and RTIs to OR 1.76 (95 % CI; 1.64, 1.88) for mold and respiratory symptoms. Most analyses were of moderate heterogeneity. Funnel plots did not indicate strong publication bias. CONCLUSION: Our results are compatible with a weak to moderate effect of residential mold and or dampness on risk of RTIs in children in high-income countries. However, these results are based primarily on cross-sectional studies.

Housing environment and mental health of Europeans during the COVID-19 pandemic: a cross-country comparison.

Many studies have investigated the impact of the COVID-19 pandemic on mental health. Throughout the pandemic, time spent at home increased to a great extent due to restrictive measures. Here we set out to investigate the relationship between housing conditions and the mental health of populations across European countries. We analyzed survey data collected during spring 2020 from 69,136 individuals from four cohorts from Denmark, France, and the UK. The investigated housing conditions included household density, composition, and crowding, access to outdoor facilities, dwelling type, and urbanicity. The outcomes were loneliness, anxiety, and life satisfaction. Logistic regression models were used, and results were pooled using random-effects meta-analysis. In the meta-analysis, living alone was associated with higher levels of loneliness (OR = 3.08, 95% CI 1.87-5.07), and lower life satisfaction (OR = 1.27, 95% CI 1.05-0.55), compared to living with others. Not having access to an outdoor space and household crowding were suggestively associated with worse outcomes. Living in crowded households, living alone, or lacking access to outdoor facilities may be particularly important in contributing to poor mental health during a lockdown. Addressing the observed fundamental issues related to housing conditions within society will likely have positive effects in reducing social inequalities, as well as improving preparedness for future pandemics.

The impact of the initial and second national COVID-19 lockdowns on mental health in young people with and without pre-existing depressive symptoms.

BACKGROUND: The evidence on mental health during COVID-19 evolved fast, but still little is known about the long-lasting impact of the sequential lockdowns. We examine changes in young people's mental health from before to during the initial and second more prolonged lockdown, and whether women and those with pre-existing depressive symptoms were disproportionally impacted. METHODS: Participants reported on mental health indicators in an ongoing 18-year data collection in the Danish National Birth Cohort and in a COVID-19 survey, including 8 data points: 7 in the initial lockdown, and 1 year post. Changes in quality of life (QoL), mental well-being, and loneliness were estimated with random effect linear regressions on longitudinal data (N = 32,985), and linear regressions on repeated cross-sections (N = 28,579). FINDINGS: Interim deterioration in mental well-being and loneliness was observed during the initial lockdown, and only in those without pre-existing depressive symptoms. During the second lockdown, a modest deterioration was again observed for mental well-being and loneliness. QoL likewise only declined among those without pre-existing symptoms, where women showed a greater decline than men. QoL did not normalise during the initial lockdown and remained at lower levels during the second lockdown. These findings were not replicated in the repeated cross-sections. INTERPRETATION: Except for an interim decrease in mental health, and only in those without pre-existing depressive symptoms, this study's findings do not suggest a substantial detrimental impact of the lockdowns.

Impact of housing conditions on changes in youth's mental health following the initial national COVID-19 lockdown: a cohort study.

We aimed to investigate if declines in youth's mental health during lockdown were dependent on housing condition among 7445 youth (median age ~ 20 years) from the Danish National Birth Cohort (DNBC), with data collected at 18 years of age and again three weeks into the first national lockdown (April 2020). We examined associations between housing conditions (access to outdoor spaces, urbanicity, household density, and household composition) and changes in mental health (mental well-being, Quality of Life (QoL) and loneliness). We report results from multivariate linear and logistic regression models. Youth without access to outdoor spaces experienced greater declines in mental well-being (vs. garden; mean difference: - 0·75 (95% CI - 1·14, - 0·36)), and correspondingly greater odds of onset of low mental well-being (vs. garden; OR: 1·72 (95% CI 1·20, 2·48)). Youth in higher density households vs. below median or living alone vs. with parents only also had greater odds of onset of low mental well-being (OR: 1·26 (95% CI 1·08, 1·46) and OR: 1·62 (95% CI 1·17, 2·23), respectively). Living in denser households (vs. below median; OR: 1·18 (95% CI 1·06, 1·33), as well as living alone (vs. with parents; OR: 1·38 (95% CI 1·04, 1·82) was associated with onset of low QoL. Living alone more than doubled odds of onset of loneliness compared to living with parents, OR: 2·12 (95% CI 1·59, 2·82). Youth living alone, in denser households, and without direct access to outdoor spaces may be especially vulnerable to mental health declines.

Maternal intake of folate during pregnancy and risk of cerebral palsy in the MOBAND-CP cohort.

BACKGROUND: Folate prevents neural tube defects and may play a role in some neurodevelopmental disorders. OBJECTIVES: We investigated whether higher intakes of periconceptional or midpregnancy folate, as recommended, were associated with a reduced risk of offspring cerebral palsy (CP). METHODS: We included participants from the Nordic collaboration cohort consisting of mother-child dyads in the Danish National Birth Cohort and the Norwegian Mother, Father, and Child Cohort Study [combined as MOthers and BAbies in Norway and Denmark (MOBAND-CP)]. A total of 190,989 live-born children surviving the first year of life were included. Missing covariate data were multiply imputed. Our exposures were defined as any or no folic acid supplementation in gestational weeks (GWs) -4 to 8 (periconceptional), 9 to 12, and -4 to 12, and supplemental, dietary, and total folate during midpregnancy (GWs 22-25). CP overall and the unilateral and bilateral spastic subtypes, as well as CP with low or moderate/high gross motor function impairments, were our outcomes of interest. RESULTS: Periconceptional folic acid supplementation was not associated with CP [adjusted odds ratio (aOR), 1.02; 95% CI: 0.82-1.28]. However, supplementation in GWs 9 to 12 was associated with a reduced risk of CP (aOR, 0.74; 95% CI: 0.57-0.96), and inverse associations were indicated for both the unilateral (aOR, 0.68; 95% CI: 0.46-1.02) and bilateral (aOR, 0.70; 95% CI: 0.49-1.02) spastic subtypes, although the associations were not statistically significant. Supplemental or dietary folate in midpregnancy alone were not associated with CP. Strong inverse associations were observed with low gross motor function impairment (aOR, 0.49; 95% CI: 0.29-0.83), while for unilateral CP the aOR was 0.63 (95% CI: 0.34-1.22) for intakes of ≥500 compared to ≤199 dietary folate equivalents/day during midpregnancy. CONCLUSIONS: Our findings suggest that folate intakes in GWs 9 to 12 and midpregnancy were associated with lower risks of CP, while no association was observed for periconceptional supplementation.

Indoor home environments of Danish children and the socioeconomic position and health of their parents: A descriptive study.

BACKGROUND: Housing and indoor home environments are associated with the risk of infections and asthma in children. To better understand the determinants and characteristics of these environments, we aimed to describe the associations between parental health and socioeconomic position and housing and indoor home environments of children in Denmark, and the clustering of the factors within these environments. METHODS: Offspring in the Danish National Birth Cohort (DNBC) whose parents responded to the 11-year follow-up were eligible for inclusion. We included complete cases only. Data on the indoor and housing environments (i.e. variables on housing, sources of gaseous and particle pollution, mould and moisture, and pets) were collected through an online questionnaire responded to by a parent. Data on socioeconomic position were obtained through linkage with registry data on maternal education at offspring birth and household equivalized income at offspring birth. Data on parental health were obtained by linking self-reported data from the 11-year follow-up for mother and father with administrative registry data for the mother. We present descriptive statistics and exploratory factor analyses. RESULTS: A total of 42 723 offspring were included for analyses. The distributions of nearly all indoor and housing environments differed according to educational and income strata, with patterns similar for both education and income. Generally, higher parental educational and income strata had more favorable indoor and housing environments (less secondhand smoking, gas stove use, mould and condensation and higher house ownership, detached house dwellings and newer building age). However, candle use was approximately similar between strata, fireplace use among lower educational and income strata tended towards the extremes (none or daily), and water damage was more common among higher educational and income strata. Parental health was strongly associated with housing and indoor home environment factors - especially parental affective disorders was strongly associated with mould. Four factors were extracted from the exploratory factor analyses, relating primarily in order of extraction to: housing ownership, mould and moisture, candle use and household density. CONCLUSION: Parental health and socioeconomic position are strongly related to housing and indoor home environments. Additionally, several factors in these environments correlate strongly and cluster together. Observational studies on associations and causal effects of factors in the indoor and housing environments of children on their morbidity, must consider both of these conclusions to arrive at valid estimates and effects.

Prenatal, infantile, and childhood tobacco exposure and risk of pediatric psoriasis in the Danish National Birth Cohort offspring.

BACKGROUND: Tobacco smoking is implicated in psoriasis among adults. OBJECTIVE: To determine whether prenatal, infantile, and childhood tobacco exposure increase risk of pediatric psoriasis. METHODS: Data from Danish National Birth Cohort participants were collected at approximately gestational week 12 and when the children were approximately 6 months and 11 years of age. In total, 25 812 offspring with complete data from the Danish National Birth Cohort were included. We estimated the odds of pediatric psoriasis with tobacco exposure prenatally, from birth to age 6 months (early infancy), and at age 11 years (childhood). RESULTS: We observed an increased risk of pediatric psoriasis among offspring with prenatal tobacco exposure (adjusted odds ratio [OR], 1.39; 95% confidence interval [CI], 1.06-1.82). An exposure-response relationship was observed for increasing quantities of cigarettes smoked daily (≥16 cigarettes: adjusted OR, 2.92; 95% CI, 1.20-7.10; P for trend = .038). The associations with infantile (adjusted OR, 1.17; 95% CI, 0.76-1.79) and childhood (adjusted OR, 1.10; 95% CI, 0.77-1.58) tobacco exposure were attenuated after controlling for prenatal exposure. LIMITATIONS: Outcome status was maternally reported. CONCLUSIONS: Prenatal tobacco exposure may increase the risk of pediatric psoriasis in a monotonic fashion, indicating that smoking may play a causal role in psoriasis pathogenesis.

Tonsillitis and pediatric psoriasis: Cohort and cross-sectional analyses of offspring from the Danish National Birth Cohort.

BACKGROUND: Streptococcal tonsillitis has been implicated in psoriasis; however, few population studies have examined its role in the pediatric population. OBJECTIVE: To investigate the association between tonsillitis and pediatric psoriasis. METHODS: Data from the Danish National Birth Cohort were obtained on parentally reported psoriasis by age 11 years and history of tonsillitis at ages 6 to 18 months, 10 to 11 years, and (from hospital patient registry data) 0 to 11 years. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) of pediatric psoriasis using logistic regression analyses. RESULTS: In total, 35 188 offspring were eligible for analyses. Tonsillitis at 6 to 18 months was not associated with pediatric psoriasis (adjusted OR, 0.73; 95% CI, 0.47-1.14), nor was recent tonsillitis at ages 10 to 11 years (adjusted OR, 1.09; 95% CI, 0.81-1.47). However, recurrent tonsillitis between ages 10 to 11 was strongly associated with pediatric psoriasis (adjusted OR, 2.28; 95% CI, 1.17-4.48). Our results for streptococcal tonsillitis indicated a potential association (adjusted OR, 2.12; 95% CI, 0.86-5.17). LIMITATIONS: It was not possible to clarify the temporal relationship between tonsillitis and pediatric psoriasis. CONCLUSION: Recurrent tonsillitis is of clinical relevance to pediatric psoriasis.

Cohort profile: the clinical 'Psoriasis in Adolescents' (PIA) cohort in Denmark.

PURPOSE: Psoriasis is a chronic inflammatory skin disease that frequently debuts in childhood and adolescence. We wished to determine environmental and genetic risk factors for the development of psoriasis in children and adolescents, as well as to investigate debut type, trigger factors, course of disease, nature and influence of stress related to both child and family and risk factors for comorbidity. The 'Psoriasis in Adolescents' (PIA) cohort will provide data on the relationship between psoriasis and, respectively, genetic disposition, early-life exposures, quality of life and comorbidity. PARTICIPANTS: The PIA cohort is nested in the large general population Danish National Birth Cohort (DNBC). We invited 390 adolescents with psoriasis and corresponding maternally predisposed and non-predisposed controls. Participants underwent an interview and a clinical examination consisting of a skin inspection and physical measurements including blood sampling and microbiological swabs. Additionally, four self-administered questionnaires on physical and mental health were completed. FINDINGS TO DATE: The final PIA cohort consists of 81 adolescents with psoriasis, 110 parentally predisposed and 124 non-predisposed psoriasis-free adolescents. The validity of the maternally reported psoriasis status from the DNBC was found to be low on clinical examination (47.5%). In contrast, the self-reported psoriasis status of the DNBC mothers was clinically confirmed in 80.8% of the cases. FUTURE PLANS: The PIA cohort offers the possibility of assessing the clinical characteristics, course of psoriasis and development of comorbidities in adolescents with clinically confirmed disease from a general population. Comparison with predisposed and non-predisposed controls is possible and genetic analyses are scheduled. We plan to invite the participants for a follow-up in 5-10 years. Furthermore, we plan to include newly diagnosed adolescents with psoriasis from the 18-year DNBC follow-up. All information is linkable on the individual level with data from the DNBC and nationwide registries in Denmark.