Utilizing MR studies, we employed genetic variations as proxies for potential exposure factors to assess their causal effects on OP. Our investigation provided substantial evidence linking various factors to an increased risk of this condition. In our analysis of the Finnish database, we identified several predictors of OP, including low educational attainment, infrequent alcohol consumption, diminished relative body shape in children, hypoglycemia, low body mass index (BMI), limited years of education, low systolic blood pressure, and conditions such as irritable bowel syndrome, primary biliary cholangitis, elevated levels of Dickkopf-related protein 1, type 1 diabetes, and both serum-positive and serum-negative rheumatoid arthritis. Additionally, high levels of sex hormone-binding globulin were recognized as a risk factor. Similarly, our examination of the UK Biobank data revealed that early menopause, low intake of non-oily fish, reduced pulse pressure, exposure to PM2.5 pollution, irritable bowel syndrome, systemic lupus erythematosus, increased years of education, menopausal status, celiac disease, and specific hemodynamic factors such as pulse pressure and menopausal age are associated with OP risk. These findings offer a comprehensive overview of the multifaceted risk factors for OP, underscoring the complexity of its etiology and the necessity for a multidisciplinary approach to prevention and treatment.
To enhance the reliability of our research findings, we applied both False Discovery Rate (FDR) correction and the more stringent Bonferroni correction to account for multiple comparisons. Our analysis of the Finnish database revealed significant correlations between the onset of OP and various factors, including primary biliary cholangitis, irritable bowel syndrome, type 2 diabetes, type 1 diabetes, serum-positive rheumatoid arthritis, sex hormone-binding globulin levels, and systolic blood pressure. In parallel, the UK Biobank database indicated that menopausal age and pulse pressure were strongly correlated with the onset of OP. Notably, even after applying the more stringent Bonferroni correction, the Finnish database continued to demonstrate robust correlations with OP for type 1 diabetes and serum-positive rheumatoid arthritis. Similarly, in the UK Biobank, the strong correlations for menopausal age and pulse pressure remained evident. These refined results, having undergone rigorous statistical scrutiny, provide a valuable reference for further investigation into the pathogenesis and risk factors associated with OP, thereby guiding future research directions and potential intervention strategies.
Through a thorough exploration of the literature across various databases, we conducted a comprehensive analysis of previously reported pathogenic risk factors for OP. Simultaneously, we investigated correlations at the genetic variation level, aiming to uncover potential etiological factors of the disease. By employing rigorous research methodologies and adopting a novel perspective, our study successfully excluded numerous pathogenic risk factors that were previously considered from a genetic variation standpoint. Additionally, it illuminated a range of risk factors that had either been controversial or overlooked in the past. The findings of our research significantly enhance the current understanding of OP and provide valuable insights for clinical research initiatives and the formulation of public health policies. We are confident that the contributions of this study will be instrumental in refining prevention and treatment strategies for OP, ultimately leading to improved patient outcomes and enhanced public health.
In this study, we utilized large-scale GWAS data to conduct a comprehensive exploration of various pathogenic risk factors associated with OP from a genetic variation perspective. We performed an extensive analysis of a wide range of risk factors previously identified in the literature as potentially linked to the disease. Our analysis encompassed multiple dimensions, including socioeconomic status, lifestyle habits, specific diseases, biochemical markers, reproductive health factors, and environmental exposures. Following this, we employed MR analysis to evaluate these factors. To our knowledge, this represents the first study to examine the pathogenic risk factors related to OP, as suggested by earlier observational studies, through the lens of genomics and GWAS data.
Socioeconomic factors and air pollution have subtle yet profound effects on the risk of OP. Our analysis, which utilized the Finnish database, identified low education levels, fewer years of education, and exposure to PM2.5 as significant risk factors. These findings highlight the complex relationship between socioeconomic status, the social environment, and bone health. The rationale behind this association is multifaceted(25-27):Individuals with lower socioeconomic status often face limited access to high-quality healthcare. Additionally, they are more likely to experience increased life stress, live in unstable housing and poor air quality conditions, and engage in unhealthy dietary habits. The interplay of these factors can negatively impact the skeletal system, thereby significantly elevating the risk of OP.
Lifestyle habits and health status have complex and varied effects on the risk of OP. Contrary to the traditional belief that alcohol consumption is harmful to health, our study, in agreement with previous research(28), demonstrates that moderate alcohol intake among elderly women is linked to significantly lower serum levels of the bone remodeling marker osteocalcin and reduced urinary levels of the bone resorption marker. These findings imply a decrease in bone remodeling activity, which may contribute to an increase in bone density.Additionally, serum parathyroid hormone levels are significantly lower in individuals who consume alcohol, which may further contribute to reduced bone resorption. Conversely, a study involving 14,237 participants found no significant correlation between drinking frequency and vertebral deformation, particularly among elderly women. However, regular moderate alcohol consumption seems to be associated with a reduced risk of disease(29). Furthermore, low body mass index (BMI) and blood sugar levels, which are directly linked to nutritional and metabolic status, have also been identified as risk factors.The association between childhood body shape and the risk of OP in adulthood highlights the necessity of adopting a life-cycle approach to bone health management. In the realm of diabetes, a phenomenon referred to as the 'diabetic bone paradox' has emerged(30), wherein individuals with type 2 diabetes (T2D) do not demonstrate significantly lower bone mineral density (BMD) yet are at an elevated risk of fractures. This paradox can be attributed to a myriad of complex factors, including changes in bone microstructure, the effects of hyperinsulinemia and hyperglycemia, the accumulation of advanced glycation end products (AGEs), and the presence of comorbidities associated with T2D. Notably, even after controlling for potential confounders, a significant correlation between T2D and higher BMD measurements, coupled with an increased fracture risk, remains evident.Longitudinal studies on type 1 diabetes have demonstrated a diminished responsiveness of bone remodeling to mechanical stimuli(31), characterized by decreased rates of both bone formation and resorption that correlate with the severity of neuropathy and the levels of diabetes control. Notably, trabecular bone formation and resorption at the distal radius in patients with type 1 diabetes are lower compared to healthy controls. Furthermore, bone formation shows a positive correlation with nerve conduction amplitude and a negative correlation with glycosylated hemoglobin levels.The utilization of vertebral bone quality (VBQ) scores has identified both increased VBQ and low body mass index (BMI) as significant risk factors for low bone mineral density(32). Furthermore, an analysis of data from the National Health and Nutrition Examination Survey (NHANES) conducted between 2007 and 2018(33), which included 1,557 adolescents, revealed a significant negative correlation between the adolescent body shape index (ABSI) and femoral bone mineral density (BMD). This correlation exhibited variations based on factors such as age, race, family income, and specific detection sites. Collectively, these findings underscore the complex interplay between lifestyle factors and health status in relation to OP risk. Factors such as alcohol consumption, diabetes status, BMI, childhood body shape, and specific indicators of bone quality are all intricately associated with OP risk to varying degrees. This understanding offers valuable insights for further elucidating the etiology of OP and provides a crucial scientific foundation for the development of more targeted prevention and treatment strategies. Therefore, continued in-depth research into these interactions, alongside the optimization of lifestyle habits and health status, is essential for mitigating OP risk and safeguarding public bone health.
Chronic conditions such as irritable bowel syndrome (IBS), primary biliary cholangitis (PBC), and rheumatoid arthritis have been recognized as significant contributors to the increased risk of OP, highlighting the complex relationship between long-term health issues and the maintenance of bone health. A retrospective cohort study conducted on the Korean population revealed that(34) individuals with IBS have substantially elevated risk ratios for OP and osteoporotic fractures, recorded at 1.476 and 1.427, respectively. This finding reinforces the strong association between IBS and compromised bone health. Additionally, a comprehensive systematic review has indicated that the risk of OP among IBS patients is significantly higher than in the non-IBS population, with a pooled risk ratio rising to 1.95(35).These findings highlight a concerning trend and underscore the necessity for integrated bone health management strategies specifically designed for patients with irritable bowel syndrome (IBS) in clinical practice. Primary biliary cholangitis (PBC), a condition closely associated with an increased risk of OP, poses an even greater challenge to bone health. Research indicates that patients with PBC are three to four times more likely to develop OP compared to the general population, with a significant majority (80%-90%) of this high-risk group being female(35-37).The susceptibility of women to bone health issues may be exacerbated by their unique physiological characteristics. A key factor in the progression of bone disease is the malabsorption of fat-soluble vitamins, particularly vitamin D, associated with primary biliary cholangitis (PBC). This malabsorption, combined with the significant depletion of vitamin D levels in affected patients, creates a detrimental cycle that further undermines bone health. Additionally, the intricate relationship between rheumatoid arthritis and OP warrants attention. Numerous studies have demonstrated a substantial correlation between these two conditions(38-40), indicating that OP frequently coexists with rheumatoid arthritis. Importantly, patients with serum-positive rheumatoid arthritis face an increased risk of both systemic and localized bone loss(41-43).This insight provides a novel perspective on the comprehensive management of rheumatoid arthritis, highlighting the importance of interdisciplinary collaboration in improving patient outcomes. In summary, these findings not only deepen our understanding of the intricate relationships between chronic diseases and OP but also establish a scientific foundation for the early identification, intervention, and holistic management of at-risk populations within clinical settings. As research advances, we expect the emergence of more precise and effective strategies for prevention and treatment, designed to alleviate the negative impacts of these conditions on bone health and to enhance the overall quality of life for affected individuals.
Ultimately, our study established that premature menopause, menopausal status, and menopausal age are critical risk factors for OP, highlighting the close relationship between women's reproductive health and bone health. This association has been supported by numerous existing studies. The underlying mechanism is attributed to the sharp decline in estrogen levels following menopause. Estrogen not only serves as a vital foundation for maintaining bone health in women but also plays a key role in regulating calcium metabolism. The postmenopausal reduction in estrogen levels places the skeletal system under dual pressures(44-46):accelerated bone resorption leads to exacerbated bone loss and a diminished capacity for calcium absorption and reabsorption, resulting in further decreases in bone strength. When compounded by the cumulative effects of unhealthy lifestyle habits and potential genetic predispositions, these factors become intertwined in postmenopausal women, significantly increasing their risk of OP. Consequently, enhancing the holistic management of women's reproductive and bone health is of paramount importance for the prevention and treatment of OP. Special attention should be given to monitoring and modulating estrogen levels while actively promoting the adoption of healthy lifestyles to mitigate the risk of OP.
As with all prior MR studies, excluding the effects of horizontal pleiotropy and establishing direct causal links presents complex challenges. To address these issues, we employed methodologies such as the Weighted Median, Simple Mode, and Weighted Mode for horizontal pleiotropy analysis, applying stringent exclusion criteria to screen genetic variants. These approaches are designed to yield unbiased estimates of causal effects. In sensitivity analyses, the effects of most characteristics significantly or suggestively associated with the risk of OP onset were found to be consistent, providing robust support for the inferred causal relationships. However, there are differences in the estimation of causal effects between the Random Effects Maximum Likelihood approach and the MR-Egger regression. The Maximum Likelihood method fully accounts for the uncertainty associated with exposure factors and potential sample overlap in two-sample MR studies, whereas the MR-Egger regression may exhibit a less pronounced detection of causal effects. Furthermore, we employed both the MR-Egger and MR-PRESSO methods to verify the presence of horizontal pleiotropy(47).The MR-Egger method provides a robust estimate of causal effects by analyzing the direct influence of genetic variation while assessing the aggregate non-zero impact of indirect pathways on the outcomes. In contrast, the MR-PRESSO method emphasizes data quality optimization, identifies and excludes outliers, and enhances the robustness of causal inference. Although these two methods have distinct focuses, they collectively offer substantial support for MR analysis. Furthermore, we acknowledge that the cases and controls in this study may partially overlap with those in previous MR analyses and recognize the potential for confounding factors. To mitigate the likelihood of false positives in our results, we employed not only the False Discovery Rate (FDR) correction but also a more stringent Bonferroni correction.
Our study reaffirms established connections while introducing a comprehensive suite of preventive strategies against OP. These strategies include reducing obesity, stabilizing blood glucose levels, maintaining healthy and consistent blood pressure, enhancing educational attainment, and moderating alcohol consumption. By addressing metabolic disorders, we can positively influence the nutritional support and metabolic functionality of osteoblasts, thereby restoring bone metabolic equilibrium. In summary, the insights derived from our research are crucial for identifying key areas for current and future primary prevention initiatives within public health. Our findings highlight the risk factors associated with the onset of OP and provide significant contributions to its prevention and treatment. We aspire that these revelations will pave the way for innovative treatment paradigms, potentially transforming the management and prevention of OP.
This study primarily focuses on individuals of European descent, and the generalizability of its findings to other ethnic groups requires further investigation. The limitations of our study include a restricted sample size and potential biases arising from uneven group distribution. Although stringent thresholds and multiple corrections have strengthened the rigor of our analysis, there remains a possibility that true associations may be overlooked in smaller samples due to insufficient statistical significance. Additionally, the subtle effects of genetic variations may reduce statistical power, thereby increasing the risk of type I errors. It is unfortunate that some observed associations between exposure factors and OP were relatively weak, suggesting that these factors may only marginally influence OP risk. Such minor changes may lack substantial clinical or statistical relevance in practical applications. Nevertheless, we acknowledge the potential influence of uncontrolled confounding factors that could obscure or diminish the true associations. The pathogenesis of OP continues to be fraught with uncertainties. There is an urgent need for large-scale, multi-center, and meticulously designed studies to address these knowledge gaps and to elucidate the interplay between various factors and OP more precisely. Such research efforts will provide robust scientific evidence to inform effective prevention and treatment strategies.