The impact of COPD on polyneuropathy: results from the German COPD cohort COSYCONET

Respiratory Research

Table 2 Results of the structural equation modelRegression

			Estimate	S.E.	C.R.	Standardized.	P
ABI	←	TLCO	.001	.000	4.600	.185	p < 0.001
BE	←	RV/TLC	5.829	.800	7.284	.291	p < 0.001
PNP	←	BE	.082	.035	2.372	.100	.020
PNP	←	ABI	1.139	.535	2.128	.091	.033
Exacerbations	←	FEV₁	−.005	.001	−5.346	−.216	p < 0.001
6-MWD	←	ABI	97.583	24.735	3.945	.130	p < 0.001
6-MWD	←	FEV₁	1.713	.229	7.493	.303	p < 0.001
6-MWD	←	TLCO	1.442	.194	7.440	.297	p < 0.001
6-MWD	←	Exacerbations	−26.189	7.665	−3.417	−.115	p < 0.001
Monofilament	←	PNP	−.079	.010	−7.562	−.322	p < 0.001
6-MWD	←	CRP	−25.565	7.507	−3.406	−.113	p < 0.001
End joint (EJ)	←	PNP	1.000			.904
Basal joint (BTBJ)	←	PNP	1.023	.076	13.413	.933	p < 0.001
SaO₂	←	TLCO	.027	.004	6.564	.254	p < 0.001
SaO₂	←	BE	−.234	.042	−5.501	−.214	p < 0.001
TUG	←	6-MWD	−.010	.001	16.231	−.562	p < 0.001
TUG	←	Monofilament	.359	.152	.018	.082	p < 0.001
Covariances			Estimate	S.E.	C.R.	Standardized	P
FEV₁	↔	TLCO	214.898	18.125	11.857	0.558	p < 0.001
TLCO	↔	RV/TLC	−.923	.099	−9.294	−0.416	p < 0.001
FEV₁		RV/TLC	−1.398	.098	−14.216	−0.734	p < 0.001

The upper panel refers to the directed arrows (regression terms) depicted in Fig. 1, whereby the left part lists the arrows shown in this figure. The right part shows the results of the corresponding statistical tests. The first column of the right part shows the non-standardized estimate of the respective regression coefficient, the second column the standard error (S.E.) of this coefficient, the third column the ratio of these two values (critical ratio, C.R.) which is used for significance testing. The fourth column shows the standardized estimates of the regression coefficients shown in the first column. The last column shows the significance level based on the generalized least squares (GLS) procedure of AMOS. In an analogous manner the lower panel shows the covariances (bidirectional arrows in Fig. 1) between lung function parameters, as well as the respective standard errors, critical ratios, correlation coefficients and significance levels. In the SEM, CRP values were logarithmically transformed (log10) after addition of 0.05, in order to account for the skewness of data and obtain a distribution closer to normal. For abbreviations of symbols see text

ISSN: 1465-993X