Table 3.

The multivariable model describing the influence of AITD and other clinically relevant modifiers on the HRQOL.

Predictor	Change in HRQOL score per unit (95% conf. interval)	P value
Analysis of generic HRQOL score
Presence of AITD	−4.60 (−8.56, −0.64)	0.023
Gender (male)	1.99 (−1.26, 5.25)	0.23
Age (per 1 year)	0.12 (−0.49, 0.74)	0.69
Diabetes duration (per 1 year)	0.21 (−0.24, 0.66)	0.36
HbA1c (per 1 mmol/mol)	−0.07 (−0.17, 0.02)	0.14
Treatment (insulin pump)	−1.68 (−5.08, 1.72)	0.33
Analysis of diabetes-specific HRQOL score
Presence of AITD	−3.61 (−8.05, 0.83)	0.11
Gender (male)	5.84 (2.23, 9.46)	0.002
Age (per 1 year)	0.23 (−0.46, 0.92)	0.51
Diabetes duration (per 1 year)	0.13 (−0.38, 0.64)	0.61
HbA1c (per 1 mmol/mol)	−0.11 (−0.22, −0.01)	0.041
Treatment (insulin pump)	−2.38 (−6.15, 1.38)	0.21

The dependent variable was the total score in the respective questionnaire. The predictors were presence of autoimmune thyroiditis (1 = AITD; 0 = no thyroid disease), along with five major diabetes-related confounders identified from the literature as well as from our univariate analysis. The coefficients represent the change in the quality of life score per one unit of predictor (i.e., presence of AITD, sex, one year of age, one mmol/mol of HbA1c, or treatment by insulin pump). This model was selected for its biological plausibility; that is, no stepwise building was employed.