Table 2—

Number of participants and percentage with oxygen desaturation, stratified by age and city

	Mexico City^#	Caracas^¶	Montevideo
Subjects
40–45 yrs	223	284	103
>45–50 yrs	351	478	232
>50–60 yrs	238	302	211
>60–70 yrs	155	203	167
>70 yrs	85	90	130
Total	1,052	1,357	843
Subjects with S_P,O₂ ≤88%
0–45 yrs	2.2 (1.0–5.1)	0.7 (0.2–2.9)	0
>45–50 yrs	3.4 (2.0–5.7)	0.4 (0.11–1.58)	0
>50–60 yrs	5.0 (2.7–9.3)	1.0 (0.3–2.9)	0
>60–70 yrs	12.9 (7.6–21.1)	2.0 (0.7–5.1)	0
>70 yrs	16.5 (9.5–27.1)	2.2 (0.6–7.8)	0
Total	6.0 (4.6–7.7)	1.0 (0.6–1.5)	0

Data are presented as n or n (95% confidence interval). S_P,O₂: arterial oxygen saturation (measured by pulse oximetry). ^#: Ten subjects reported home oxygen use; ^¶: four subjects reported home oxygen use.