Risk factors for depression in patients with chronic obstructive pulmonary disease

Table 4 Cutoff value, sensitivity, and specificity of body mass index, forced expiratory volume in 1 s, and chronic obstructive pulmonary disease assessment test score for diagnosing depression

Factors	Cutoff value	Sensitivity (%)	Specificity (%)	AUC	95%CI	P value
BMI (kg/m2)	21.375	49.6	83.1	0.705	0.633-0.776	0.001
FEV1 (L)	0.855	71.5	63.1	0.702	0.634-0.770	0.003
CAT score	12.5	63.1	70.6	0.694	0.624-0.765	0.001
BMI+FEV1		76.9	66.7	0.745	0.684-0.807	0.000
BMI+CAT		72.3	67.1	0.735	0.669-0.802	0.000
FEV1+CAT		76.9	60.5	0.730	0.667-0.794	0.000
BMI+FEV1+CAT		72.3	75.0	0.766	0.705-0.827	0.000

BMI: Body mass index; FEV1: Forced expiratory volume in 1 s; CAT: Chronic obstructive pulmonary disease assessment test; AUC: Area under curve; CI: Confidence interval.