Hua Sun, Xin Shen, Kegao Liu
Based on this study involving US adults as a research sample, low systemic bone mineral density is independently associated with increased odds of presumed nasolacrimal duct obstruction. These findings support the hypothesis that osteoporotic changes in the bony nasolacrimal canal may contribute to the etiology of this condition, particularly in postmenopausal women. Further longitudinal studies are warranted to confirm causality.
BACKGROUND: It is well-documented that primary acquired nasolacrimal duct obstruction (PANDO) is a prevalent cause of epiphora in the elderly population. While local inflammation and hormonal factors have been implicated, the potential influence of systemic skeletal health, in particular osteoporosis to the bony nasolacrimal canal remains poorly understood. Therefore, this study aimed to explore the association between systemic Bone Mineral Density (BMD) and presumed Nasolacrimal Duct Obstruction (NLDO) in a representative sample of US adults.
METHODS: This cross-sectional study analyzed data from the National Health and Nutrition Examination Survey (NHANES) 2005-2008 cycles. Participants aged 40 years and older with valid dual-energy X-ray absorptiometry (DXA) measurements and complete ocular symptom questionnaires were included. Presumed NLDO was defined as self-reported frequent tearing in the absence of dry eye symptoms or ocular allergies. Survey-weighted logistic regression models were utilized and adjusted for sociodemographic and comorbidity covariates. Restricted cubic spline (RCS) analysis and subgroup interaction tests were conducted to explore non-linear relationships and effect modification.
RESULTS: A total of 5423 participants were included in the final analysis, representing a weighted population of approximately 64 million US adults. The weighted prevalence of presumed NLDO was 8.4%. Participants with presumed NLDO had significantly lower lumbar spine BMD compared to controls (0.94 vs. 1.02 g/cm2, P < 0.001). In the fully adjusted multivariable model, every 1-standard deviation (SD) decrease in lumbar spine BMD was associated with a 32% increase in the odds of presumed NLDO (OR = 1.32, 95% CI: 1.15-1.52). Meanwhile, individuals with osteoporosis had an 86% higher odds of presumed NLDO compared to those with normal BMD (OR = 1.86, 95% CI: 1.34-2.58). Interaction analyses revealed that the association was significantly stronger in females (P for interaction = 0.038) and older adults aged >60 years (P for interaction = 0.042).
CONCLUSION: Based on this study involving US adults as a research sample, low systemic bone mineral density is independently associated with increased odds of presumed nasolacrimal duct obstruction. These findings support the hypothesis that osteoporotic changes in the bony nasolacrimal canal may contribute to the etiology of this condition, particularly in postmenopausal women. Further longitudinal studies are warranted to confirm causality.