Psoriasis Among Adolescents in Kuwait and the Role of Siblings, Breastfeeding, and Household Cat and Secondhand Smoke Exposure: A Cross-Sectional Study

Parental Consanguinity and Family History in Relation to Psoriasis and the Role of Sex: A Case-Control Study

INTRODUCTION

Psoriasis is caused by an interplay between intrinsic and extrinsic factors. Parental consanguinity increases homozygosity in the genome of the offspring, which in turn increases disease risk. The association between parental consanguinity and psoriasis in the offspring remains unexplored. Therefore, this study sought to evaluate the association of parental consanguinity and family history with psoriasis in the offspring and to determine whether sex modulates the aforementioned associations.

METHODS

A case-control study enrolled adults aged 21 years and more. Psoriasis cases (n = 139) diagnosed by dermatologists were enrolled from dermatology clinics. Controls (psoriasis-free subjects; n = 278) were enrolled from workplaces. Study subjects reported information on parental consanguinity and family history of psoriasis. Logistic regression was applied to evaluate associations, and adjusted odds ratios (aOR) and 95% confidence intervals (CIs) were estimated.

RESULTS

Cases compared to controls were more likely to report parental consanguinity (59.7% vs. 35.6%; p < 0.001) and family history of psoriasis (56.8% vs. 23.7%; p < 0.001). Both parental consanguinity (aOR: 2.13, 95% CI: 1.29-3.50) and family history of psoriasis (aOR: 3.43, 95% CI: 2.07-5.67) were associated with increased odds of having psoriasis. The observed association between parental consanguinity and psoriasis differed according to sex (pinteraction = 0.008), with parental consanguinity being associated with psoriasis among males (aOR: 5.96, 95% CI: 2.39-14.82), but not among females (aOR: 1.36, 95% CI: 0.75-2.49).

CONCLUSION

Psoriasis cases compared to controls were significantly more likely to report parental consanguinity and family history of psoriasis, with parental consanguinity being associated with psoriasis among males only.

Association of psoriasis with allergic multimorbidity of asthma, rhinitis, and eczema among adolescents: a cross-sectional study

BACKGROUND

Associations between psoriasis and allergic diseases (asthma, rhinitis, and eczema) in children have been reported in a limited number of studies, and the association between psoriasis and multimorbidity (co-occurrence) of allergic diseases remains unclear. Hence, this study aimed to assess the association between psoriasis and the co-occurrence of asthma, rhinitis, and eczema in adolescents.

METHODS

This school-based cross-sectional study enrolled adolescents (n = 3,864) aged 11-14 years. Parents completed a questionnaire on doctor-diagnosed psoriasis as well as symptoms and clinical history of asthma, rhinitis, and eczema. Eight nonoverlapping groups comprising single and co-occurring current (past 12 months) asthma, rhinitis, and eczema were identified. A multinomial logistic regression model was used to estimate the adjusted odds ratios (aOR) and 95% confidence intervals (CI).

RESULTS

In the analytical sample (n = 3,710; 1,641 male and 2,069 female participants), 3.5% reported doctor-diagnosed psoriasis, and 15.7%, 15.0%, and 10.3% had current asthma, rhinitis, and eczema symptoms, respectively. Doctor-diagnosed psoriasis was associated with "asthma only" (aOR = 2.11, 95% CI: 1.15-3.89), "eczema only" (6.65, 4.11-10.74), "asthma + eczema" (5.25, 2.36-11.65), "rhinitis + eczema" (3.60, 1.07-12.15), and "asthma + rhinitis + eczema" (7.38, 2.93-18.58). Doctor-diagnosed psoriasis was not statistically significantly associated with "rhinitis only" (1.42, 0.71--2.84) and "asthma + rhinitis" (1.78, 0.69-4.56).

CONCLUSION

Our findings indicate that psoriasis is associated with the co-occurrence of allergic diseases among adolescents. However, further studies are required to investigate which biological mechanisms may be shared between psoriasis and allergic diseases.

Breastfeeding decreases the risk of developing psoriasis through to early adulthood

BACKGROUND

Psoriasis is a genetically determined systemic skin disease, although environmental trigger factors are required for disease manifestation. Some of these triggers, such as stress, infections and drug exposure, have been identified.

OBJECTIVES

To explore the role of early nutrition as a risk factor for the development of psoriasis.

METHODS

Parents in the All Babies in Southeast Sweden (ABIS) prospective birth cohort (n = 16 415) answered questionnaires at birth and when their children were aged 1 and 3 years. A diagnosis of psoriasis was determined from the Swedish National Patient Register and National Drug Prescription Register. Statistical analyses were conducted using custom-written R scripts.

RESULTS

Individuals breastfed for < 4 months and who received infant formula before 4 months of age had a higher risk of psoriasis [odds ratio (OR) 1.84 (P = 0.02) and OR 1.88 (P = 0.02), respectively]. At the 3-year follow-up, the increased consumption of fish, especially from the Baltic Sea, increased the risk of psoriasis (OR 9.61; P = 0.003). In addition, the risk of psoriasis increased following the consumption of a large volume of milk (OR 2.53; P = 0.04).

CONCLUSIONS

Our study underscores, for the first time, the impact of very early nutrition on the manifestation of psoriasis through early adulthood. Exclusive breastfeeding for 4 months appears to be protective.

Sex Differences in the Association of Sibship Size and Position in Sibship with Lipid Profile during Adolescence: A Cross-Sectional Study

BACKGROUND

Epidemiologic studies have reported associations of sibship size and position of the child in the sibship with multiple health outcomes, including adiposity and diabetes. However, little is known about sibling effects on lipids. Hence, this study sought to evaluate associations of the number of total, older, and younger siblings with lipid profile among adolescents.

METHODS

In a cross-sectional study among high school students aged 14 to 19 years, lipid levels were measured in capillary blood. Parents reported the number of siblings (total, older, and younger). Geometric means of lipids were calculated, and linear regression was used to estimate the ratio of geometric means (RoGM) and 95% confidence intervals (CI). Analyses were sex stratified.

RESULTS

Of the total study sample (n = 1,584), 758 (47.9%) were boys and 826 (52.1%) were girls, with median age of 16.0 years. Total cholesterol (TC) was lower by 8% (adjusted-RoGM = 0.92, 95% CI: 0.88-0.96) among boys with ≥3 older siblings compared to those with no older siblings. Similarly, boys with ≥3 younger sibling compared to those with no younger siblings had reduced TC by 7% (adjusted-RoGM = 0.93, 0.87-0.99). Moreover, an increased number of total siblings (≥4 vs. 0/1: adjusted-RoGM = 0.80, 0.67-97) and older siblings (≥3 vs. 0: adjusted-RoGM = 0.90, 0.82-0.98) were associated with reduced low-density lipoprotein cholesterol (LDL-C) among boys. Similarly, lower levels of triglycerides (TG) were seen among boys with ≥3 older siblings compared to those with no older siblings (adjusted-RoGM = 0.87, 0.78-0.96). A higher number of younger siblings was associated with increased high-density lipoprotein cholesterol (HDL-C) among boys (≥3 vs. 0: adjusted-RoGM = 1.08, 1.01-1.17). Sibship characteristics were not associated with lipids among girls.

CONCLUSIONS

Increased number of total, older, and younger siblings were associated with favorable lipid profiles among adolescent boys, but not girls. Mechanisms underlying these associations need further investigations.