# Accelerometer-based assessment of occupational standing time and its association with venous disorders – results of a cross-sectional field study

## TL;DR

This study used accelerometers to track work-related standing time and found that age and family history, not standing duration, are linked to venous disorders.

## Contribution

The study introduces a novel use of wearables to objectively assess occupational standing time and its association with venous disorders.

## Key findings

- Neither daily nor long-term cumulative standing time was significantly associated with varicose veins or venous reflux.
- Age and family history were significant predictors of venous disorders.
- Objective activity tracking via accelerometers provided more reliable data than prior methods.

## Abstract

Pathophysiologically, prolonged standing is associated with varicose veins (VV) or pathological venous reflux. Prior work-related epidemiological studies are inconclusive due to crude and imprecise exposure assessments. This cross-sectional field study explored the association between work-related standing time and VV or pathological reflux, assessed using wearables. Daily standing time was tracked by accelerometer and categorized: ≤2 vs. >2 but ≤4 vs. >4 h. Long-term cumulative standing exposure were estimated by combining accelerometer and survey data. Employees underwent CEAP classification and duplex ultrasound to measure lower leg reflux. The associations between standing time and other predictors on VV or reflux were analyzed by multiple logistic regression. 198 employees working ≥30 h and ≥4 days per week for ≥2y in logistics, trade, retail, manufacturing, healthcare, research, and service sectors were included (n = 116♀, Ø-age = 40 ± 9y). 18% (n = 36) stood ≤2 h, 46% (n = 91) >2 but ≤4 h, 36% (n = 71) >4 h per day. Long-term cumulative standing exposure was 10,145.0 ± 8,396.0 h. 24% (n = 47) were described with VV, 38% (n = 74) with reflux. While neither daily nor long-term cumulative standing time were significantly associated with VV or reflux, age and family history were. Our findings partly contradict previous epidemiological studies, highlighting the value of objectively measured activity patterns for future research.

The online version contains supplementary material available at 10.1038/s41598-026-38327-8.