The proposed study will evaluate (for newly diagnosed Chronic Obstructive Pulmonary Disease (COPD) patients)the time taken to prescription of triple therapy by aiming to answer these following research questions:

1. The percentage of patients prescribed triple therapy, and when they first started receiving triple therapy.
2. For patients prescribed triple therapy, the time taken to triple therapy from initial diagnosis of COPD.
3. The variation in treatment pathways.
4. The factors associated with time taken to triple therapy.

Triple therapy consists of long-acting beta agonist (LABA) + inhaled corticosteroids (ICS) + long-acting muscarinic antagonist (LAMA) and typically should be reserved for patients who have severe to very severe (FEV1 <50%) COPD symptoms or for patients who have two or more exacerbations per year. However previous research from RiRL indicate that 50% of patients at GOLD stage II (moderate) receive ICS of which half were on triple therapy.

To allow for multiple analysis regarding the factors that influence the likelihood of being prescribed triple therapy, a bespoke COPD dataset will be created to include:

1. Disease severity markers:
2. Confirmation of a COPD diagnosis at initial date of COPD diagnosis
3. Standard co-morbidities fields
4. Demographic fields

This retrospective, observational study using data of COPD patients will assess treatment pathways (changes/step up) from initial date of COPD diagnosis with the prescription of triple therapy as the endpoint.

Specific questions that will be asked are:

1. Does the percentage of COPD patients prescribed triple therapy vary dependent on time of initial date of COPD diagnosis?
2. Does the time taken to the prescription of triple therapy vary dependent on initial date of COPD diagnosis?

Inclusion Criteria:

• Aged ≥40 years at initial date of COPD diagnosis
• COPD diagnosis with Quality Outcome Framework (QoF) approved read code
• has spirometry data supportive of a COPD diagnosis in the 5 years around initial date diagnosis of COPD (FEV1 % predicted)
• Patient has one year of data prior to initial date of COPD diagnosis
• Patient has a minimum of two years of data post initial date of COPD diagnosi

Exclusion Criteria:

• Patients whose initial date of COPD diagnosis is before 1997

Patients will have a QoF approved COPD read code and must be aged ≥ 40.