32867 Association of sun-protective behaviors with bone mineral density and osteoporotic bone fractures in the United States: National Health and Nutrition Examination Survey 2017-18

Abstract

Introduction: Despite the reassuring emerging evidence on the lack of causality between sun protection and vitamin D deficiency, scarce data exist on whether multimodal sun protection is associated with the adverse bone-related outcomes. This may lead to excessive worry and suboptimal sun protection on the part of patients. We aimed to investigate the association of sun-protective behaviors (shade stay, wearing long-sleeved clothing, and sunscreen use) with bone mineral density (BMD) and the prevalence of osteoporotic fractures. Methods: In a population-based, cross-sectional setting, sampled participants’ data (n = 3418) representative of the United States adult population (aged ≥20 years old) were accessed from the National Health and Nutrition Examination Survey 2017-18 and analyzed. Results: The use of individual sun-protective modalities was not associated with diminished site-specific and total BMD z-scores in the multivariate models (estimate [95% confidence interval, P value] = frequent shade stay: −0.225 [−0.466 to 0.017, .182], wearing of long sleeves: −0.076 [−0.269 to 0.117, .724], and sunscreen use: −0.098 [−0.321 to 0.125, .153]). Moderate-to-frequent stay in the shade correlated with reduced prevalence of spine fractures in the multivariate model (odds ratio [95% confidence interval] for frequent shade stay: 0.193 [0.044 to 0.857], P = .017). Conclusions: Routine use of sun-protective modalities was not associated with decreased BMD or the osteoporotic fracture risk. Sun protection may be associated with a modest decrease in the prevalence of osteoporotic fractures, possibly due to risk-averse behaviors. These reassuring findings add to the growing body of evidence on the safety of sun protection, with no significant negative impact on bone health.