How to account for Inuit ancestry in lung function prediction

Figures & data

Table 1. Demographic data for the Inuit and non-Inuit participants.

	Inuit n = 351			non-Inuit n = 29
	Mean	SD	Range	Mean	SD	Range
Age years	38.3	13.5	16.0 to 65.6	49.3	11.1	20.0 to 68.1
Recorded Height m	1.68	0.08	1.44 to 1.90	1.74	0.10	1.55 to 1.92
Modified Height m	1.75	0.09	1.48 to 1.98	-	-	-
BMI Kg·m^−2	26.2	5.4	16.8 to 53.8	27.5	3.9	17.7 to 34.0
Modified BMI Kg·m^−2	24.4	5.1	15.6 to 49.7	-	-	-

Figure 1. Histograms of the z-scores for FEV1 and FVC for the 351 people of Inuit descent calculated by GLI using recorded height (panels A & C) and with height modified for SHR (panels B & D).

Figure 2. Histograms of the z-scores for FEV1/FVC for the 351 people of Inuit descent calculated by GLI using recorded height (panel A) and when using height modified for SHR (panel B).

Figure 3. Plot of GLI FEV1 z-scores for the 351 Inuit participants using modified height against age.

Table 2. Table of z-score values for FEV1, FVC and FEV1/FVC for the 351 Inuit with recorded height and height modified for SHR and the 29 non-Inuit participants.

		Inuit n = 351			Inuit Modified Ht n = 351				non-Inuit n = 29
	Median	Mean	SD	Range	Median	Mean	SD	Range	Median	Mean	SD	Range
zFEV1	0.56	0.53	1.36	−3.24 to 5.75	−0.07	−0.12	1.24	−3.45 to 4.53	0.35	0.15	1.17	−3.74 to 1.68
zFVC	0.77	0.81	1.20	−2.57 to 5.28	0.06	0.10	1.10	−2.96 to 4.12	−0.10	0.12	0.91	−1.97 to 1.87
zFEV1/FVC	−0.34	−0.45	0.98	−3.56 to 2.27	−0.29	−0.39	0.99	−3.53 to 2.36	0.21	−0.01	1.04	−4.57 to 1.35

Table 3. Mean (SD) z-scores for spirometric indices in the 33 participants with physician diagnosed asthma and the 347 non-asthmatics, together with the mean difference (95% confidence limits) between those with asthma and non-asthma.

				Diff
		Asthma	Non-Asthma	A-NonA
Recorded Ht:	zFEV1	0.07 (1.42)	0.54 (1.34)	−0.47 (−0.95 to 0.01)
	zFVC	0.50 (1.23)	0.78 (1.19)	−0.28 (−0.71 to 0.15)
	zFEV1/FVC	−0.67 (1.13)	−0.40 (0.97)	−0.28 (−0.69 to 0.14)
Modified Ht:	zFEV1	−0.48 (1.32)	−0.07 (1.23)	−0.41 (−0.85 to 0.03)
	zFVC	−0.12 (1.12)	0.12 (1.08)	−0.24 (−0.62 to 0.15)
	zFEV1/FVC	−0.62 (1.13)	−0.34 (0.98)	−0.28 (−0.70 to 0.13)