Screening scores
BMI Calculator for Sleep Apnea Risk
Excess body weight is one of the strongest risk factors for obstructive sleep apnea, and BMI over 35 is one of the eight STOP-Bang items. Enter your weight and height to calculate your BMI and the adult category the CDC uses.
How it works
Metric: BMI = weight (kg) / height (m) squared. US units: BMI = 703 x weight (lb) / height (in) squared.
Example
200 lb and 69 inches: 703 x 200 / 69^2 = 140,600 / 4,761 = 29.5, overweight under the CDC categories, and below the STOP-Bang threshold of 35.
Assumptions and limits
- Adult categories only; children and teens use age and sex specific BMI percentiles.
- BMI does not measure body fat directly and can misclassify very muscular people and some ethnic groups.
- Sleep apnea also occurs in people with a healthy BMI, especially with a small jaw, large tonsils or other airway features.
Frequently asked questions
How does weight affect sleep apnea?
Fat around the neck and upper airway can narrow the airway and make it collapse more easily during sleep. NHLBI lists overweight and obesity among the main risk factors, and weight loss can reduce severity in many people.
Will losing weight cure my sleep apnea?
It can lower the AHI and sometimes resolve mild disease, but many people still need treatment. Do not stop CPAP without a follow-up evaluation.
Why does STOP-Bang use BMI 35?
The STOP-Bang authors chose BMI over 35 as the cutoff for the B item when they developed the questionnaire.
Sources
Tools and screening scores are general information. They cannot diagnose or rule out a sleep disorder. Read our medical disclaimer.