Participants

The process of patient recruitment and consent for the follow-up interviews is shown in Fig. 1. The 400 patients who participated in the follow-up interviews had a mean age of 65.2 years at the time of randomisation in SLS COPD and 53.8% were male. Over half of the participants (56.3%) were cohabiting with a partner. Only 11.4% of participants were working in a full-time, part-time or voluntary capacity; 67.0% were retired, 12.3% were unemployed or homemakers and 5% were on long-term sick leave. More than one-third of participants (37%) were current smokers while 53.8% were former smokers. More than 60% of participants reported having at least one other long-term illness or health condition in addition to their COPD; 43.8% had an illness that limited their physical activity or mobility and 5.3% reported having a psychological or emotional condition.

Fig. 1 Patient recruitment and consent process COPD chronic obstructive pulmonary disease, EOS end-of-study, SLS COPD The Salford Lung Study in COPD Full size image

In the year prior to SLS COPD, 20% of participants had experienced no exacerbations while 27% had experienced one exacerbation and 53% had experienced two or more exacerbations. During SLS COPD, 31.3, 23.3 and 45.5% of participants experienced none, one, or at least two exacerbations, respectively. Of those subjects who participated in the exit interviews, approximately half had been randomised to initiate treatment with FF/VI 100/25 μg (48.3%) while the other half continued usual care (51.8%). Characteristics of the follow-up participants according to number of COPD exacerbations they experienced during SLS COPD are shown in Supplementary Table 1.

The characteristics of the follow-up participants have been previously shown to be reasonably representative of the overall sample of patients who completed SLS COPD (n = 2600) in terms of age, gender and exacerbation history in the year prior to SLS COPD.19

Differences between participants, according to initiated treatment group

Perceived control over COPD

Participants’ perceptions of their control over COPD and change in perceived control during the course of SLS COPD are shown in Fig. 2 and Fig. 3, respectively. The reported perceived levels of control patients had over their COPD at the time of the follow-up interview were similar between the FF/VI and usual care treatment groups. However, more patients in the FF/VI group than in the usual care group reported an improvement in their perceived control over COPD during the study (38.3% [74/193] vs 27.1% [56/207], respectively). This was particularly noticeable in the percentage of participants who reported that their COPD had improved ‘a lot’ since the start of SLS COPD (23.3% [45/193] vs 15.5% [32/207], respectively).

Fig. 2 Perceived control over COPD during SLS COPD FF/VI participants initiated treatment with fluticasone furoate/vilanterol, QoL quality of life, SLS COPD Salford Lung Study in patients with chronic obstructive pulmonary disease, UC usual care Full size image

Fig. 3 Perceived change in control over COPD during SLS COPD FF/VI participants initiated treatment with fluticasone furoate/vilanterol, QoL quality of life, SLS COPD Salford Lung Study in patients with chronic obstructive pulmonary disease, UC usual care Full size image

Reported impact of COPD on participants’ QoL

The mean (standard deviation [SD]) overall QoL score (assessed on a response scale of 1–10, with higher scores indicating better QoL) was 6.5 (2.1) in both the FF/VI and usual care treatment groups. The impact of COPD on the QoL domains of functioning, activities, relationships, psychological well-being and independence assessed on a scale of 1–4, with higher scores indicating greater impact were similar in both treatment groups, with mean scores of 2.0–2.5 across all domains in the FF/VI group and 2.1–2.5 in the usual care group. The highest scores were recorded in the functioning and activities domains.

The impact of COPD on various aspects of participants’ daily lives within each of these QoL domains is shown in Table 1. Similar mean scores were observed for the individual questions on life area impact among patients randomised to initiate treatment with FF/VI or continue usual care. Climbing stairs or lifting/carrying were movements or activities within the functioning domain that were most impacted by COPD in both groups, with mean scores of 2.8–2.9 and 2.6–2.7, respectively. Within the activities domain, COPD had the greatest impact on physical activities (mean score of 2.7 in both treatment groups) and least impact on personal care (mean score of 1.5 in both treatment groups). Slight differences in mean scores between the FF/VI and usual care groups were observed for ‘loss of independence’ in the independence domain (1.6 [SD 1.0] vs 1.8; [SD 1.0]) and for ‘get anxious or worried about my COPD’ (1.8 [SD 1.0] vs 2.0 [SD 1.0]), and ‘find coughing embarrassing’ (2.0 [SD 1.1] vs 2.2 [SD 1.1]) in the psychological domain. In each of these cases, more patients randomised to usual care than to FF/VI reported greater (i.e., worse) impacts of COPD on these issues.

Table 1 Reported impact of COPD on QoL Full size table

Perceived change in overall QoL and in the daily life impact of COPD on the QoL domains during SLS COPD are shown in Fig. 4 and Fig. 5a–e, respectively. A higher percentage of patients randomised to FF/VI than those randomised to usual care reported an improvement in overall QoL since the start of SLS COPD (44.4 vs 27.1%, respectively); more patients receiving usual care felt that their overall QoL had worsened compared with those randomised to initiate FF/VI (26.6 vs 15.5%, respectively; Fig. 4). A higher percentage of patients randomised to FF/VI than to usual care also reported an improvement in the effect of daily life impact across all QoL domains (Fig. 5a–e). These results were particularly evident for the functioning and activities domains, where the difference between treatment groups reporting an improvement was approximately 3-times higher among patients randomised to FF/VI versus usual care (functioning: 39.4 vs 11.5%; activities 30.0 vs 11.6%, respectively; Fig. 5a, c).

Fig. 4 Perceived change in overall QoL during SLS COPD FF/VI participants initiated treatment with fluticasone furoate/vilanterol, QoL quality of life, SLS COPD Salford Lung Study in patients with chronic obstructive pulmonary disease, UC usual care Full size image

Fig. 5 a, b, c, d, e. Perceived change in the daily life impact of COPD on QoL domains during SLS COPD QoL quality of life, SLS COPD Salford Lung Study in patients with chronic obstructive pulmonary disease, UC usual care Full size image

Reported sleep impairment

For the COPD and Asthma Sleep Impact Scale (CASIS), similar scores were observed across the two treatment groups. Mean (SD) scores were 43.7 (27.9) for FF/VI and 43.9 (28.9) for usual care. Median scores were slightly lower (less sleep impairment) for FF/VI than for usual care (42.9 and 46.4, respectively).

Relationships between exacerbation rates and key patient-centred variables

Sociodemographic and lifestyle characteristics

In general, there was little association between the exacerbation rate during SLS COPD and many of the sociodemographic, health and disease factors explored in the follow-up interviews (Supplementary Tables 1, 2 and 3). Of the patients not experiencing exacerbations, 62.4% (78/125) were male and 37.6% (47/125) were female. This trend was then replicated among the patients experiencing one exacerbation, with 60.2% (56/93) being male and 39.8% (37/93) being female. For patients experiencing two or more exacerbations, the majority were female (56.6% female [103/182] vs 43.4% male [79/182]; Supplementary Table 1). Relationship status and employment status were broadly similar between patients with no, one, or two or more exacerbations (Supplementary Table 1). A higher percentage of patients who experienced two or more exacerbations (12.6% [23/182]) saw a hospital specialist for their COPD compared with those with no exacerbations (5.6% [7/125]) or one (5.4% [5/93]) exacerbation (Supplementary Table 2). The same was true of patients seeing respiratory nurses; 18.1% (33/182) of patients that experienced two or more exacerbations saw a respiratory nurse compared with 13.6% (17/125) that experienced none and 10.8% (10/93) that experienced one. Similar proportions of patients saw general practitioners and practice nurses for COPD (Supplementary Table 2). A higher percentage of patients who experienced two or more exacerbations were current smokers (40.7% [74/182]) compared with those having no exacerbations (32.8% [41/125]) or one exacerbation (35.5% [33/93]). Among patients who had ever experienced an exacerbation (n = 266), those who experienced two or more exacerbations in SLS COPD were the most frequent of the exacerbation subgroups to report that they would be aware when an exacerbation is about to happen (69.9% [102/146]) (Supplementary Table 3). For patients who experienced one exacerbation or no exacerbations in SLS COPD, 58.1% (36/62) and 53.4% (31/58), respectively, reported that they would be aware of an exacerbation about to happen.

Perceived control over COPD

A greater percentage of patients who had experienced two or more exacerbations during SLS COPD reported having ‘no control’ or ‘little control’ over their COPD compared with those who had experienced no exacerbations during the study (46.2 vs 31.2%, respectively; Fig. 6). Moreover, more patients who had experienced two or more exacerbations during SLS COPD reported that their feelings of control had worsened either ‘a lot’ or ‘a little’ since the start of SLS COPD compared with patients who experienced no exacerbations (12.6 vs 3.2%, respectively; Fig. 7). Conversely, fewer patients who experienced two or more exacerbations reported a perceived improvement in feelings of control over COPD since the start of SLS COPD compared with those who had one or no exacerbations (24.7 vs 35.5% and 41.6%, respectively; Fig. 7). Additional data are reported in Supplementary Table 3.

Fig. 6 Perceived control over COPD according to the number of COPD exacerbations experienced during SLS COPD Full size image

Fig. 7 Perceived change in control over COPD according to the number of COPD exacerbations experienced during SLS COPD Full size image

Reported impact of COPD on participants’ QoL and coping mechanisms

Patients who experienced a greater number of exacerbations during SLS COPD reported a worse impact of COPD on multiple aspects of daily life (Table 1). Mean (SD) scores on the overall QoL questionnaire (assessed on a scale of 1−10, with higher scores indicating better QoL) were 6.9 (2.2) for patients with no exacerbations, 6.7 (2.0) for patients with one exacerbation, and 6.2 (2.0) for patients with two or more exacerbations during SLS COPD. Fewer patients who experienced two or more exacerbations reported an improvement in overall QoL since the start of SLS COPD compared with those with one or no exacerbations (26.4 vs 36.6% and 47.2%, respectively), and more felt that their overall QoL had worsened during the study (31.9, 17.2 and 8.8% for patients with two or more, one, or no exacerbations, respectively).

With regard to perceived environmental triggers (Fig. 8a–d and Fig. 9a–d), the percentage of patients who ‘always’ avoid such triggers ranged from 27.5−68.1% for those who experienced two or more exacerbations during SLS COPD, compared with 17.2–48.4% and 14.4–48.8% for patients who experienced one or no exacerbations during SLS COPD, respectively (Fig. 8a–d). A greater percentage of patients with two or more exacerbations reported that they avoided these perceived triggers more since the start of SLS COPD compared with patients who experienced one or no exacerbations (Fig. 9a–d).

Fig. 8 a, b, c, d. SLS COPD follow-up interview participants’ avoidance of perceived triggers for COPD exacerbations according to the number of COPD exacerbations experienced during SLS COPD Full size image