# Analysis of risk factors for calf muscular vein thrombosis in elderly patients with acute exacerbation of chronic obstructive pulmonary disease

## TL;DR

This study identifies risk factors for calf muscle vein blood clots in elderly patients with worsening chronic lung disease.

## Contribution

Identifies three independent risk factors for calf muscular vein thrombosis in elderly COPD patients during acute episodes.

## Key findings

- Reduced calf circumference is a strong predictor of CMVT (OR=0.25).
- Elevated red blood cell count significantly increases CMVT risk (OR=19.85).
- Higher D-dimer levels are independently associated with CMVT (OR=1.84).

## Abstract

This study aimed to identify the independent risk factors for calf muscular vein thrombosis (CMVT) in elderly patients experiencing an acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

A retrospective study was conducted involving 128 elderly patients (age ≥60 years) with AECOPD. Patients were categorized into CMVT and non-CMVT groups based on lower extremity venous color Doppler ultrasound findings. Clinical characteristics and laboratory parameters were compared between the groups. Statistically significant variables from univariate analysis were incorporated into a multivariate logistic regression analysis to identify independent risk factors. The predictive performance of these factors was evaluated using receiver operating characteristic (ROC) curve analysis.

Multivariate logistic regression identified reduced calf circumference [Odds Ratio (OR) = 0.25, 95% Confidence Interval (CI): 0.1–0.59], elevated red blood cell (RBC) count (OR = 19.85, 95% CI: 1.08–363.96), and elevated D-dimer level (OR = 1.84, 95% CI: 1.13–3.01) as independent risk factors for CMVT. ROC curve analysis demonstrated good predictive performance for these factors, with areas under the curve (AUC) of 0.986 for calf circumference, 0.788 for RBC count, and 0.976 for D-dimer.

Reduced calf circumference, elevated RBC count, and elevated D-dimer level are significant independent risk factors for CMVT in elderly AECOPD patients. Monitoring these indicators could aid clinicians in the early identification and prevention of CMVT in this vulnerable population.