Decreased Bone Mineral Density Is a Predictor of Poor Survival in Critically Ill Patients

Bone mineral density as potential individual prognostic biomarker in patients with neurosurgically treated spinal metastasis

INTRODUCTION

Bone mineral density (BMD) plays a crucial role in diagnosing and treating various systemic chronic diseases. Patients with multiple or singular spinal metastasis (SM) are typically in advanced stages of systemic cancer, often leading to significant alterations in BMD. The present study investigated the prognostic value of perioperative Hounsfield units (HU) as a surrogate independent marker for estimated BMD in patients with SM after surgical treatment (ST).

METHODS

HU values, serving as a surrogate for estimated BMD, were measured from circular regions of interest (ROIs) in the spine -first lumbar vertebra (L1)- from routine preoperative staging computed tomography (CT) scans in 187 patients after ST. The estimated BMD was stratified into pathologic and physiologic values and correlated with survival parameters in our cohorts.

RESULTS

Median L1 BMD of 92 patients (49%) with pathologic BMD was 79.5 HU (IQR 67.25-93.5) compared to 145 HU (IQR 123-166) for 95 patients (51%) with physiologic BMD (p ≤ 0.001). Patients with pathological BMD exhibited a median overall survival of 8 months compared to 12.2 months in patients with physiologic BMD (p = 0.006). Multivariable analysis revealed pathologic BMD as an independent negative prognostic predictor for increased 1 year mortality (AUC: 0.637, 95% CI: 0.556-0.718; p = 0.001).

CONCLUSIONS

The present study demonstrates that decreased perioperative BMD values, as derived from HU measurements, may represent a previously unrecognized negative prognostic factor in patients of SM after ST. The estimated perioperative BMD could emerge as an individualized, readily available potential biomarker for prognostic, treatment, and discussion of affected patients with SM.

Unravelling the pandemic: impaired bone metabolism and risk of SARS-CoV-2 infection

INTRODUCTION

While the impact of COVID-19 on bone metabolism has been extensively studied, the inverse relationship remains less understood. This study investigates whether impaired bone metabolism is associated with an increased risk of COVID-19 infection.

METHODS

We conducted a nested case-control study within a population-based cohort, incorporating Kaplan-Meier analysis (KMA) to assess time to infection (TTI) differences. Propensity score matching (1:2) was performed and validated through standardized mean differences (<0.10), variance ratio (=1), and McFadden's pseudo-R2 (=0), ensuring balanced covariates. Bone status was evaluated using a composite index (AOMI), which included five components: P1NP and CTX (bone turnover markers), total hip bone mineral density (BMD-TH), trabecular bone score (TBS), and integral volumetric BMD (IvBMD). Inflammation and insulin resistance (IR) were assessed by albumin-to-globulin ratio (AGR <1.50) and the TG/HDL ratio (>2.50 in women and >2.80 in men), respectively.

RESULTS

We analysed 294 COVID-19 cases and 528 controls. AOMI+ individuals had a higher prevalence of COVID-19 (41.5% vs. 33.2%; p = 0.031), an adverse lipid pattern ("A" profile: high ApoB, LDL and TC) and pronounced bone changes (higher P1NP and CTX, lower BMD-TH, TBS, and IvBMD). AOMI - individuals were more likely to have metabolic syndrome, displayed a different lipid profile ("B" profile: elevated TG, AIP, and TG/HDL ratio), fewer bone alterations, and lower COVID-19 prevalence. TG/HDL ratio was 1.66 ± 1 in "A" profile, while it was 2.85 ± 1.4 in "B" profile individuals (p = 0.0001). Age acted as an effect modifier, and lowest tercile significantly increased COVID-19 risk associated with AOMI+ [Mantel-Haenszel OR = 1.42 (95%CI: 1.08-1.9); p = 0.022]. KMA identified AOMI+ men and individuals of both sexes in lowest age tercile, as groups with shorter TTI: These younger individuals had high CTX (women), low TBS (men), and high ApoB (both). In multivariable analyses, plasma CTX levels negatively correlated with TTI (adjusted β= -0.325; p = 0.0001). AOMI+ status was associated with increased COVID-19 risk after controlling for confounders, including IR (adjusted OR = 1.51; 95%CI: 1.04-2.10; p = 0.027), although this association weakened when adjusting for AGR (95%CI: 0.99-2.28; p = 0.055). ANCOVA-estimated adjusted TBS means were lower in COVID-19 cases compared to controls (1.259 vs. 1.294; p = 0.013).

CONCLUSIONS

Impaired bone metabolism was found to be associated with increased COVID-19 risk, in a relationship potentially mediated by underlying inflammation. Elevated osteoclastic activity and a defined lipid profile with high ApoB, TC, LDL levels, played a crucial role in the results. Bone quality parameters more accurately captured COVID-19-related bone changes than BMD.

Novel association between chronic obstructive pulmonary disease and osteoporosis: A prospective cross-sectional study

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a progressive respiratory condition often associated with a high incidence of osteoporosis. Studies indicate that patients with COPD present with a significant decrease in bone mineral density (BMD), potentially related to inflammation and corticosteroid use.

AIM

To investigate the relationship between BMD and lung function, mainly the forced expiratory volume in the forced expiratory volume in 1 second (FEV1)/ forced vital capacity percentage (FVC%), in patients with COPD using quantitative computed tomography (QCT).

METHODS

This prospective cross-sectional study included 85 patients with COPD treated at Gansu Provincial People's Hospital. Exposure variables included lung function parameter (FEV1/FVC%), age, sex, body mass index, smoking status, tea-drinking habits, and physical activity. BMD was measured using QCT. Linear regression and generalized additive models were employed to analyze the relationship between exposure variables and BMD.

RESULTS

Linear regression analysis revealed a significant positive relationship between BMD and FEV1/FVC% (β = 0.1, 95% confidence interval [CI]: 0.1-0.1; P < 0.0001). Non-linear analysis identified a unique BMD breakpoint of 128.08 mg/cm³. Before the breakpoint, BMD was significantly positively correlated with FEV1/FVC% (β = 0.245; P = 0.0019); while after the breakpoint, the relationship was negative and showed no statistical significance (β = -0.136; P = 0.0753). This finding underscores the critical role of BMD in COPD management and highlights the importance of individualized clinical interventions in improvement of lung function and overall health status in patients.

CONCLUSION

There is a complex non-linear relationship between BMD and lung function in patients with COPD, highlighting the importance of monitoring change in bone density during the management of COPD.

Bone mineral density as a prognostic marker in patients with biliary tract cancer undergoing surgery

Background

Biliary tract cancer (BTC) is one of the most aggressive malignancies and surgery represents the only curative treatment approach. However, even in patients with complete tumor resection 5-year survival rates are below 30%. So far, prognostic markers to assess the outcome of these patients are lacking. We therefore evaluated bone mineral density (BMD) as a prognostic tool in patients receiving surgery for BTC.

methods

76 BTC patients undergoing tumor resection in our clinic (Duesseldorf cohort) as well as an external validation cohort of 34 BTC patients (Cologne cohort) were included. BMD was analyzed at the first lumbar vertebra, using routine CT scans which has been proven comparable to DXA.

Results

Median overall survival (OS) of the Duesseldorf cohort after surgery was 527 days, one- and five-year survival probabilities were 62 and 18%. Patients with BMD above 156.5 HU had significantly improved OS (1435 days vs. 459 days; p = 0.002). The prognostic value for BMD was confirmed using Cox-regression analysis, as well as an external validation cohort. In subgroup analysis the prognostic effect of BMD was only present in female patients, suggesting sex specific differences.

Conclusion

BMD is a valuable, easily accessible and independent prognostic marker in patients receiving liver surgery for BTC.

GENETIC PREDICTION OF CAUSAL RELATIONSHIPS BETWEEN OSTEOPOROSIS AND SEPSIS: EVIDENCE FROM MENDELIAN RANDOMIZATION WITH TWO-SAMPLE DESIGNS

ABSTRACT

Background: Recent observational studies have suggested that osteoporosis may be a risk factor for sepsis. To mitigate confounding factors and establish the causal relationship between sepsis and osteoporosis, we conducted a two-sample Mendelian randomization analysis using publicly available summary statistics. Methods: Utilizing summary data from FinnGen Biobank, we employed a two-sample Mendelian randomization (MR) analysis to predict the causal relationship between osteoporosis and sepsis. The MR analysis primarily utilized the inverse variance weighted (IVW) method, supplemented by MR-Egger, weighted median, weighted mode, and simple mode analyses, with Bayesian weighted MR (BWMR) analysis employed for result validation. Sensitivity analyses included MR-PRESSO, "leave-one-out" analysis, MR-Egger regression, and Cochran Q test. Results: In the European population, an increase of one standard deviation in osteoporosis was associated with an 11% increased risk of sepsis, with an odds ratio (OR) of 1.11 (95% CI, 1.06-1.16; P = 3.75E-06). BWMR yielded an OR of 1.11 (95% CI, 1.06-1.67; P = 1.21E-05), suggesting osteoporosis as a risk factor for sepsis. Conversely, an increase of one standard deviation in sepsis was associated with a 26% increased risk of osteoporosis, with an OR of 1.26 (95% CI, 1.11-1.16; P = 0.45E-03). BWMR yielded an OR of 1.26 (95% CI, 1.09-1.45; P = 1.45E-03), supporting sepsis as a risk factor for osteoporosis. Conclusion: There is an association between osteoporosis and sepsis, with osteoporosis serving as a risk factor for the development of sepsis, while sepsis may also promote the progression of osteoporosis.

Bone Mineral Density as an Individual Prognostic Biomarker in Patients with Surgically-Treated Brain Metastasis from Lung Cancer (NSCLC)

Patients with BM are in advanced stages of systemic cancer, which may translate into significant alterations of body composition biomarkers, such as BMD. The present study investigated the prognostic value of BMD on overall survival (OS) of 95 patients with surgically-treated BM related to NSCLC. All patients were treated in a large tertiary care neuro-oncological center between 2013 and 2018. Preoperative BMD was determined from the first lumbar vertebrae (L1) from routine preoperative staging computed tomography (CT) scans. Results were stratified into pathologic and physiologic values according to recently published normative reference ranges and correlated with survival parameters. Median preoperative L1-BMD was 99 Hounsfield units (HU) (IQR 74-195) compared to 140 HU (IQR 113-159) for patients with pathological and physiologic BMD (p = 0.03), with a median OS of 6 versus 15 months (p = 0.002). Multivariable analysis revealed pathologic BMD as an independent prognostic predictor for increased 1-year mortality (p = 0.03, OR 0.5, 95% CI 0.2-1.0). The present study suggests that decreased preoperative BMD values may represent a previously unrecognized negative prognostic factor in patients of BM requiring surgery for NSCLC. Based on guideline-adherent preoperative staging, BMD may prove to be a highly individualized, readily available biomarker for prognostic assessment and treatment guidance in affected patients.

Bone Mineral Density Is a Predictor of Mortality in Female Patients with Cholangiocellular Carcinoma Undergoing Palliative Treatment

Background: Cholangiocellular adenocarcinoma (CCA) is a rare and aggressive malignancy originating from the bile ducts. Its general prognosis is poor as therapeutic options are limited. Many patients present with advanced stages of disease, and palliative chemotherapy remains the only treatment option. Prognostic markers to assess the outcome of chemotherapeutic treatment in CCA are limited. We therefore evaluated bone mineral density (BMD) as a prognostic tool in patients with advanced CCA. Patients and Methods: We included 75 patients with advanced CCA that were treated at our academic tumor center. Prior to treatment, bone mineral density was analyzed at the first lumbar vertebra using routine CT scans in the venous phase and the local PACS (IntelliSpace PACS, Philips, Amsterdam, The Netherlands). Results: BMD was not significantly different between male and female patients but decreased with age. Patients with BMD above 167 HU have a significantly improved overall survival (474 days vs. 254 days; log-rank X²(1) = 6.090; p = 0.014). The prognostic value of BMD was confirmed using univariate (HR 2.313 (95%CI: 1.170–4.575); p = 0.016) and multivariate (HR 4.143 (95%CI: 1.197–14.343); p = 0.025) Cox regression analyses. Subgroup analysis revealed that the prognostic value of BMD was only present in female patients and not in male patients, suggesting sex-specific differences. Conclusions: Our data suggest that BMD is a valuable, easily accessible, and independent prognostic marker for overall survival in patients with advanced CCA. Furthermore, subgroup analysis showed the sex specificity of this marker, which demonstrated relevance only in female patients.

Osteoporosis is a novel risk factor of infections and sepsis: A cohort study

BACKGROUND

Accumulating evidence suggests the interaction of bone metabolism and the immune system, but how bone health is associated with the risk of infections remains unknown.

METHODS

This study aimed to investigate the relationship of bone mineral density (BMD) with the risk of common infections and sepsis in Hong Kong Osteoporosis Study (HKOS). A prospective cohort study, initiated in 1995 and followed until 31 December 2020, of 5,717 participants examined the association of BMD at three skeletal sites (lumbar spine, femoral neck, and total hip) with common infections - pneumonia, urinary tract infection (UTI), skin infection, and sepsis. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI).

FINDINGS

During the median follow-up of 17 years, higher BMD T-scores at the femoral neck and total hip were significantly associated with the reduced risk of pneumonia (HRs 0.89 and 0.87; 95% CIs 0.82 to 0.98 and 0.81 to 0.95), UTI (HRs 0.85 and 0.86; 95% CIs 0.76 to 0.94 and 0.78 to 0.95), skin infection (HRs 0.85 and 0.82; 95% CIs 0.74 to 0.97 and 0.73 to 0.93), and sepsis (HRs 0.83 and 0.82; 95% CIs 0.71 to 0.97 and 0.72 to 0.94). A significant association was observed for the lumbar spine BMD T-score with the risk of skin infection (HR 0.86; 95% CI: 0.78 to 0.95) but not with other infections and sepsis. Similarly, participants with osteoporosis, but not osteopenia, were significantly associated with an increased risk of infections and sepsis compared to those with normal BMD.

INTERPRETATION

BMD is a novel risk factor of infections and sepsis. People with low BMD, particularly those with osteoporosis, are at higher risk of infections and sepsis than those with normal BMD. Further studies on whether improving bone health can reduce the risk of infections and sepsis are warranted.

FUNDING

None.