Association between inhalant allergies and bone mass in young adults assessed by radial quantitative ultrasound

Background: Allergic diseases may affect skeletal health through chronic inflammation and immune-mediated mechanisms. However, evidence in young adults remains limited. Objective: The aim of this study was to examine the association between inhalant allergy and bone mass in men and women aged 18–30 years. Subjects and methods: The study included 649 young adults (256 men and 393 women). Bone mass was assessed using quantitative ultrasound (Sunlight MiniOmni) of the left radius (a non-dominant site, minimising the influence of mechanical loading), with the Z-score used as the outcome measure. Participants were classified into three groups: inhalant allergy (IA; mites, pollen, grasses, and mould), other allergy (OA; food and animal allergies), and no allergy (NA). Analyses were conducted separately for men and women using two regression models: a base model (Model 1) including covariates (BMI, history of wrist fracture, vitamin D and calcium supplementation), and a lifestyle model (Model 2) including smoking, alcohol consumption, and physical activity. Results: Regression analyses revealed sex-specific differences. In men, IA was significantly negatively associated with Z-score in both models (Model 1: β=-0.331, p=0.011; Model 2: β=-0.357, p=0.006), indicating reduced bone mass. In women, IA was positively associated with Z-score in Model 1 (β=0.214, p=0.039) and Model 2 (β=0.221, p=0.037), indicating higher bone mass. Conclusions: Inhalant allergy was associated with bone mass in a sex-specific manner, with less favourable bone health in men but not in women. The divergent pattern observed between sexes may reflect differences in hormonal and immune-mediated mechanisms, potentially involving the bone-protective role of oestrogen in women and greater susceptibility to inflammation-driven bone resorption in men; further research is needed. Allergic diseases may therefore be an important factor in anthropological research on skeletal health and biological variability.

Allergy · Body mass index · Bone density · Bone mineral · Cross-sectional study · Peak bone mass · Vitamin D and neurology · Young adult