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Updated: Jul 15, 2025

A Model to Simulate Clinically Relevant Hypoxia in Humans
Published on: December 22, 2016
Physiological association of the breakpoint with the duration of hyperventilation
Ayesha Sadiqa1, Ambreen Khalid1, Abdullah Islam1
1From the Physiology Department (Sadiqa), CMH Lahore Medical College and Institute of Dentistry,; and from thePhysiology Department (Khalid, Abdullah)), Shalamar Medical and Dental College, Lahore, Pakistan.
Objectives:
To determine the relationship of body mass index (BMI) with breath-holding time (BHT) as well as that of BHT with the duration of hyperventilation (DOH) in young healthy adults.
Methods:
An observational study was performed at Shalamar Medical and Dental College, Lahore, Pakistan, between May 2021 and June 2022. Healthy first-year Bachelor of Medicine, Bachelor of Surgery students aged 18-22 years, with a normal BMI were included. Spirometric measurements were taken through a spirometer pod connected to a pneumotachometer (model: Power Lab 26T). Body mass index was calculated as the weight (kg) to height (m2) ratio. Pearson correlation, linear regression, and t tests were applied using SPSS.
Results:
A total of 101 subjects participated, comprising of 44 men and 57 women. A weak negative association was found between BMI and BHT in all subjects (r= -0.08, p=0.34), in men (r= -0.24, p=0.11), and in women (r= -0.092, p=0.497). Furthermore, a strong association was observed between BHT and DOH in all subjects (r=0.64, p=0.000), in men (r=0.604, p=0.000), and in women (r=0.518, p=0.000). Moreover, a nonsignificant weak inverse linear regression was found between the BMI and BHT of all subjects (β= -0.087, p=0.38), of men (β= -0.241, p=0.11), and of women (β= -0.092, p=0.49). Lastly, a significantly strong positive regression was observed between the BHT and DOH of all subjects (β=0.637, p=0.000), of men (β=0.604, p=0.000), and of women (β=0.518, p=0.000).
Conclusion:
No association was found between BMI and BHT. A strong positive association was observed between BHT and DOH in all healthy young people.
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