TABLE 3.

Univariate regression models of age- and duration-adjusted skin collagen variables versus HbA_lc

Collagen versus HbA1c	R2 (%)	P
Acid-soluble (%) versus
Mean HbA1c up to biopsy†	4.2	<0.011
Mean HbA1c over the past year†	2.4	<0.078
HbA1c nearest to biopsy	2.0	<0.041
Screening HbA1c	0.4	NS*
Pepsin-soluble (%) versus
Mean HbA1c up to biopsy†	15.0	<0.001
Mean HbA1c over the past year	16.4	<0.001
HbA1c nearest to biopsy	17.0	<0.001
Screening HbA1c	0.4	NS*
Relative fluorescence versus
Mean HbA1c up to biopsy	6.5	<0.001
Mean HbA1c over the past year	6.6	<0.001
HbA1c nearest to biopsy	5.5	<0.001
Screening HbA1c	3.1	<0.010
Furosine (pmol/mg) versus
Mean HbA1c up to biopsy	19.4	<0.001
Mean HbA1c over the past year	72.3	<0.001
HbA1c nearest to biopsy	69.4	<0.001
Screening HbA1c	3.0	<0.012
Pentosidine (pmol/mg) versus
Mean HbA1c up to biopsy	8.9	<0.001
Mean HbA1c over the past year	9.6	<0.001
HbA1c nearest to biopsy	9.6	<0.001
Screening HbA1c	1.7	<0.058
CML (pmol/mg) versus
Mean HbA1c up to biopsy	16.1	<0.001
Mean HbA1c over the past year	14.4	<0.001
HbA1c nearest to biopsy	13.8	<0.001
Screening HbA1c	2.6	<0.020

^*HbA_1c effect not significant.

^†Based on a regression model with significant quadratic HbA_1c effect.