Table 4.

Longitudinal correlations between anxiety and HRQoL in chronic obstructive pulmonary disease

Reference	Anxiety measure	HRQoL measure	Length of follow-up	Sample size	Correlation (r)	P-value
Oga et al39	HAD-A	SGRQ total	1 year	128	0.412	<0.001
	HAD-A	CRQ total	1 year	128	−0.534	<0.001
	HAD-A	SGRQ total	5 years	72	0.505	<0.001
	HAD-A	CRQ total	5 years	72	−0.641	<0.001
Coventry et al40	HAD-A	SGRQ total	3 months	79	0.369	0.002
	HAD-A	SGRQ total	1 year	62	0.258	0.052

Abbreviations: HAD-A, Hospital Anxiety and Depression Scale anxiety subscale; HRQoL, health-related quality of life; SGRQ, St George’s Respiratory Questionnaire; CRQ, Chronic Respiratory Questionnaire.