Hospital Anxiety and Depresion, assessed using Hospital Anxiety and Depression Scale (HADS), have been associated with patients suffering from Chronic Obstructive Pulmonary Disease (COPD). The Hospital Anxiety and Depression Scale (HADS) (Zigmond & Snaith, 1983) is a 14-item measure designed to assess anxiety and depression symptoms in medical patients, with emphasis on reducing the impact of physical illness on the total score. The depression items tend to focus on the anhedonic symptoms of depression. Items are rated on a 4-point severity scale. The HADS produces two scales, one for anxiety (HADS–A) and one for depression (HADS–D), differentiating the two states. Scores of greater than or equal to 11 on either scale indicate a definitive case. (https://www.sciencedirect.com/topics/medicine-and-dentistry/hospital-anxiety-and-depression-scale)
HADS consists of two subscales, one measuring anxiety, with seven items, and another measuring depression, with seven items, which score separately. Each item was answered by the patient on a 4-point (0-3) scale, so the possible scores ranged from 0 to 21 for each of the two subscales, taking 2-5 minutes to complete.2,3 The HADS manual indicates that a score between 0 and 7 is "normal," between 8 and 10 "mild," between 11 and 14 "moderate," and between 15 and 21 "severe."
To understand and find the relationship between HAD Score and the factors affecting it, the correlation and regression models were used. The study on copd cohort included features like age, gender, copd assesment test score (CAT), 6-minute walking test, various other comorbidities.
The study found that CAT score was positively correlated with higher HAD score. It was also found that quality of life (SGQR) was also positively correlated with HAD score. It was also found that most people suffering from mild COPD, were having HAD score less than 10. While moderate to very severe COPD didn't show any relation. The age barely had any significant effect on HAD score. With median of 9 HADS, we can say that 50% of the population showed normal to mild Anxiety and Depression.
HADS has been blamed of having low diagnostic accuracy in practice, and it is not considered as right tool for identifying and measuring Anxiety and Depression in patients.