Elizabeth Limb

50 years of asthma: UK trends from 1955 to 2004

Trends in asthma indicators from population surveys (prevalence) and routine statistics (primary care, prescriptions, hospital admissions and mortality) in the UK were reviewed from 1955 to 2004. The prevalence of asthma increased in children by 2 to 3-fold, but may have flattened or even fallen recently. Current trends in adult prevalence are flat. The prevalence of a life-time diagnosis of asthma increased in all age groups. The incidence of new asthma episodes presenting to general practitioners increased in all ages to a plateau in the mid 1990s and has declined since. During the 1990s, the annual prevalence of new cases of asthma and of treated asthma in general practice showed no major change. Hospital admissions increased from the early 1960s, more so in children, until the late 1980s and have fallen since. Asthma mortality showed two waves, a shorter and more intense one in the mid 1960s and a longer and less intense one in the late 1970s and early 1980s. The relative roles of diagnostic transfer, coding changes, medical care and epidemiological factors are discussed.

A primary care nurse-delivered walking intervention in older adults: PACE (pedometer accelerometer consultation evaluation)-lift cluster randomised controlled trial

Background Brisk walking in older people can increase step-counts and moderate to vigorous intensity physical activity (MVPA) in ≥10-minute bouts, as advised in World Health Organization guidelines. Previous interventions have reported step-count increases, but not change in objectively measured MVPA in older people. We assessed whether a primary care nurse-delivered complex intervention increased objectively measured step-counts and MVPA. Methods and Findings A total of 988 60–75 year olds, able to increase walking and randomly selected from three UK family practices, were invited to participate in a parallel two-arm cluster randomised trial; randomisation was by household. Two-hundred-ninety-eight people from 250 households were randomised between 2011 and 2012; 150 individuals to the intervention group, 148 to the usual care control group. Intervention participants received four primary care nurse physical activity (PA) consultations over 3 months, incorporating behaviour change techniques, pedometer step-count and accelerometer PA intensity feedback, and an individual PA diary and plan. Assessors were not blinded to group status, but statistical analyses were conducted blind. The primary outcome was change in accelerometry assessed average daily step-counts between baseline and 3 months, with change at 12 months a secondary outcome. Other secondary outcomes were change from baseline in time in MVPA weekly in ≥10-minute bouts, accelerometer counts, and counts/minute at 3 months and 12 months. Other outcomes were adverse events, anthropometric measures, mood, and pain. Qualitative evaluations of intervention participants and practice nurses assessed the intervention’s acceptability. At 3 months, eight participants had withdrawn or were lost to follow-up, 280 (94%) individuals provided primary outcome data. At 3 months changes in both average daily step-counts and weekly MVPA in ≥10-minute bouts were significantly higher in the intervention than control group: by 1,037 (95% CI 513–1,560) steps/day and 63 (95% CI 40–87) minutes/week, respectively. At 12 months corresponding differences were 609 (95% CI 104–1,115) steps/day and 40 (95% CI 17–63) minutes/week. Counts and counts/minute showed similar effects to steps and MVPA. Adverse events, anthropometry, mood, and pain were similar in the two groups. Participants and practice nurses found the intervention acceptable and enjoyable. Conclusions The PACE-Lift trial increased both step-counts and objectively measured MVPA in ≥10-minute bouts in 60–75 year olds at 3 and 12 months, with no effect on adverse events. To our knowledge, this is the first trial in this age group to demonstrate objective MVPA increases and highlights the value of individualised support incorporating objective PA assessment in a primary care setting. Trial Registration Controlled-Trials.com ISRCTN42122561

Effect of a Primary Care Walking Intervention with and without Nurse Support on Physical Activity Levels in 45- to 75-Year-Olds: The Pedometer And Consultation Evaluation (PACE-UP) Cluster Randomised Clinical Trial.

Background Pedometers can increase walking and moderate-to-vigorous physical activity (MVPA) levels, but their effectiveness with or without support has not been rigorously evaluated. We assessed the effectiveness of a pedometer-based walking intervention in predominantly inactive adults, delivered by post or through primary care nurse-supported physical activity (PA) consultations. Methods and Findings A parallel three-arm cluster randomised trial was randomised by household, with 12-mo follow-up, in seven London, United Kingdom, primary care practices. Eleven thousand fifteen randomly selected patients aged 45–75 y without PA contraindications were invited. Five hundred forty-eight self-reporting achieving PA guidelines were excluded. One thousand twenty-three people from 922 households were randomised between 2012–2013 to one of the following groups: usual care (n = 338); postal pedometer intervention (n = 339); and nurse-supported pedometer intervention (n = 346). Of these, 956 participants (93%) provided outcome data (usual care n = 323, postal n = 312, nurse-supported n = 321). Both intervention groups received pedometers, 12-wk walking programmes, and PA diaries. The nurse group was offered three PA consultations. Primary and main secondary outcomes were changes from baseline to 12 mo in average daily step-counts and time in MVPA (in ≥10-min bouts), respectively, measured objectively by accelerometry. Only statisticians were masked to group. Analysis was by intention-to-treat. Average baseline daily step-count was 7,479 (standard deviation [s.d.] 2,671), and average time in MVPA bouts was 94 (s.d. 102) min/wk. At 12 mo, mean steps/d, with s.d. in parentheses, were as follows: control 7,246 (2,671); postal 8,010 (2,922); and nurse support 8,131 (3,228). PA increased in both intervention groups compared with the control group; additional steps/d were 642 for postal (95% CI 329–955) and 677 for nurse support (95% CI 365–989); additional MVPA in bouts (min/wk) were 33 for postal (95% CI 17–49) and 35 for nurse support (95% CI 19–51). There were no significant differences between the two interventions at 12 mo. The 10% (1,023/10,467) recruitment rate was a study limitation. Conclusions A primary care pedometer-based walking intervention in predominantly inactive 45- to 75-y-olds increased step-counts by about one-tenth and time in MVPA in bouts by about one-third. Nurse and postal delivery achieved similar 12-mo PA outcomes. A primary care pedometer intervention delivered by post or with minimal support could help address the public health physical inactivity challenge. Clinical Trial Registration isrctn.com ISRCTN98538934.

A primary care pedometer-based walking intervention with and without practice nurse support: PACE-UP cluster-randomised controlled trial

Abstract Background WHO guidelines recommend walking to increase moderate-to-vigorous physical activity. Pedometer-based interventions have focused on step-counts, not moderate-to-vigorous physical activity, and have not distinguished between pedometer and support effects. We assessed whether a postal pedometer-based walking intervention could increase step-counts and moderate-to-vigorous physical activity in inactive adults and whether physical activity consultations delivered by a practice nurse could add benefit. Methods 11 015 men and women aged 45–75 years, randomly selected from seven family practices in London, UK, with no physical activity contraindications, were invited by post to participate in a parallel three-arm cluster-randomised trial. Randomisation was by household, stratified by practice, using random-sized blocks. 6399 were non-responders; 548 repondents who self-reported achievement of physical activity guidelines were excluded. 1023 people (922 households) were randomised after consent to usual care (338), postal pedometer intervention (339), or nurse-supported pedometer intervention (346). Intervention groups received pedometers, 12 week walking programmes, and physical activity diaries. The nurse group was offered three physical activity consultations. Assessors were unmasked to group for pragmatic reasons. The primary and main secondary outcomes were, respectively, changes from baseline to 12 months in average daily step-counts and time in moderate-to-vigorous physical activity in bouts (≥10 min), measured over 7 days objectively by accelerometry. Analysis accounted for clustering, was by intention to treat, and was masked to group for main outcomes. Ethics approval was granted by the London Research Ethics Committee (Hampstead). This trial is registered with Current Controlled Trials, ISRCTN98538934. Findings Recruitment rate was 10% (1023/10 467). 955 participants (93%) provided 12 month outcome data. Baseline mean number of step-counts and time in moderate-to-vigorous physical activity in bouts for those randomised were 7479 steps per day (SD 2671) and 94 min/week (102), respectively. Both intervention groups significantly increased number of step-counts and time in moderate-to-vigorous physical activity in bouts compared with controls, with no significant differences between interventions: postal intervention 641 additional steps per day (95% CI 328–954), nurse-support 682 (371–994); postal intervention 33 min/week of additional bouts of moderate-to-vigorous physical activity (17–49), nurse-support 35 (19–51). Interpretation A primary care pedometer-based walking intervention in inactive 45–75-year-olds increased step-counts by about a tenth and increased time in moderate-to-vigorous physical activity in bouts by a third. There was no evidence that nurse delivery had a greater effect on 12 month physical activity outcomes than simpler, resource-efficient postal delivery. A primary care postal pedometer intervention could help address the challenge of public health physical inactivity. Funding National Institute for Health Research Health (NIHR) Technology Assessment (HTA) Programme (project number HTA 10/32/02). This project will be published in full in Health Technology Assessment . The funding body was not involved in the study design, collection, analysis, and interpretation of data, writing of the abstract, or the decision to submit for publication.

Physical activity levels in adults and older adults 3–4 years after pedometer-based walking interventions: Long-term follow-up of participants from two randomised controlled trials in UK primary care

Background Physical inactivity is an important cause of noncommunicable diseases. Interventions can increase short-term physical activity (PA), but health benefits require maintenance. Few interventions have evaluated PA objectively beyond 12 months. We followed up two pedometer interventions with positive 12-month effects to examine objective PA levels at 3–4 years. Methods and findings Long-term follow-up of two completed trials: Pedometer And Consultation Evaluation-UP (PACE-UP) 3-arm (postal, nurse support, control) at 3 years and Pedometer Accelerometer Consultation Evaluation-Lift (PACE-Lift) 2-arm (nurse support, control) at 4 years post-baseline. Randomly selected patients from 10 United Kingdom primary care practices were recruited (PACE-UP: 45–75 years, PACE-Lift: 60–75 years). Intervention arms received 12-week walking programmes (pedometer, handbooks, PA diaries) postally (PACE-UP) or with nurse support (PACE-UP, PACE-Lift). Main outcomes were changes in 7-day accelerometer average daily step counts and weekly time in moderate-to-vigorous PA (MVPA) in ≥10-minute bouts in intervention versus control groups, between baseline and 3 years (PACE-UP) and 4 years (PACE-Lift). PACE-UP 3-year follow-up was 67% (681/1,023) (mean age: 59, 64% female), and PACE-Lift 4-year follow-up was 76% (225/298) (mean age: 67, 53% female). PACE-UP 3-year intervention versus control comparisons were as follows: additional steps/day postal +627 (95% CI: 198–1,056), p = 0.004, nurse +670 (95% CI: 237–1,102), p = 0.002; total weekly MVPA in bouts (minutes/week) postal +28 (95% CI: 7–49), p = 0.009, nurse +24 (95% CI: 3–45), p = 0.03. PACE-Lift 4-year intervention versus control comparisons were: +407 (95% CI: −177–992), p = 0.17 steps/day, and +32 (95% CI: 5–60), p = 0.02 minutes/week MVPA in bouts. Neither trial showed sedentary or wear-time differences. Main study limitation was incomplete follow-up; however, results were robust to missing data sensitivity analyses. Conclusions Intervention participants followed up from both trials demonstrated higher levels of objectively measured PA at 3–4 years than controls, similar to previously reported 12-month trial effects. Pedometer interventions, delivered by post or with nurse support, can help address the public health physical inactivity challenge. Trial registrations PACE-UP isrctn.com ISRCTN98538934; PACE-Lift isrctn.com ISRCTN42122561.

Housing, neighbourhood and sociodemographic associations with adult levels of physical activity and adiposity: baseline findings from the ENABLE London study

Objectives The neighbourhood environment is increasingly shown to be an important correlate of health. We assessed associations between housing tenure, neighbourhood perceptions, sociodemographic factors and levels of physical activity (PA) and adiposity among adults seeking housing in East Village (formerly London 2012 Olympic/Paralympic Games Athletes’ Village). Setting Cross-sectional analysis of adults seeking social, intermediate and market-rent housing in East Village. Participants 1278 participants took part in the study (58% female). Complete data on adiposity (body mass index (BMI) and fat mass %) were available for 1240 participants (97%); of these, a subset of 1107 participants (89%) met the inclusion criteria for analyses of accelerometer-based measurements of PA. We examined associations between housing sector sought, neighbourhood perceptions (covariates) and PA and adiposity (dependent variables) adjusted for household clustering, sex, age group, ethnic group and limiting long-standing illness. Results Participants seeking social housing had the fewest daily steps (8304, 95% CI 7959 to 8648) and highest BMI (26.0 kg/m2, 95% CI 25.5kg/m2 to 26.5 kg/m2) compared with those seeking intermediate (daily steps 9417, 95% CI 9106 to 9731; BMI 24.8 kg/m2, 95% CI 24.4 kg/m2 to 25.2 kg/m2) or market-rent housing (daily steps 9313, 95% CI 8858 to 9768; BMI 24.6 kg/m2, 95% CI 24.0 kg/m2 to 25.2 kg/m2). Those seeking social housing had lower levels of PA (by 19%–42%) at weekends versus weekdays, compared with other housing groups. Positive perceptions of neighbourhood quality were associated with higher steps and lower BMI, with differences between social and intermediate groups reduced by ~10% following adjustment, equivalent to a reduction of 111 for steps and 0.5 kg/m2 for BMI. Conclusions The social housing group undertook less PA than other housing sectors, with weekend PA offering the greatest scope for increasing PA and tackling adiposity in this group. Perceptions of neighbourhood quality were associated with PA and adiposity and reduced differences in steps and BMI between housing sectors. Interventions to encourage PA at weekends and improve neighbourhood quality, especially among the most disadvantaged, may provide scope to reduce inequalities in health behaviour.

Short-term and long-term cost-effectiveness of a pedometer-based exercise intervention in primary care: a within-trial analysis and beyond-trial modelling

Objectives A short-term and long-term cost-effectiveness analysis (CEA) of two pedometer-based walking interventions compared with usual care. Design (A) Short-term CEA: parallel three-arm cluster randomised trial randomised by household. (B) Long-term CEA: Markov decision model. Setting Seven primary care practices in South London, UK. Participants (A) Short-term CEA: 1023 people (922 households) aged 45–75 years without physical activity (PA) contraindications. (b) Long-term CEA: a cohort of 100 000 people aged 59–88 years. Interventions Pedometers, 12-week walking programmes and PA diaries delivered by post or through three PA consultations with practice nurses. Primary and secondary outcome measures Accelerometer-measured change (baseline to 12 months) in average daily step count and time in 10 min bouts of moderate to vigorous PA (MVPA), and EQ-5D-5L quality-adjusted life-years (QALY). Methods Resource use costs (£2013/2014) from a National Health Service perspective, presented as incremental cost-effectiveness ratios for each outcome over a 1-year and lifetime horizon, with cost-effectiveness acceptability curves and willingness to pay per QALY. Deterministic and probabilistic sensitivity analyses evaluate uncertainty. Results (A) Short-term CEA: At 12 months, incremental cost was £3.61 (£109)/min in ≥10 min MVPA bouts for nurse support compared with control (postal group). At £20 000/QALY, the postal group had a 50% chance of being cost saving compared with control. (B) Long-term CEA: The postal group had more QALYs (+759 QALYs, 95% CI 400 to 1247) and lower costs (−£11 million, 95% CI −12 to −10) than control and nurse groups, resulting in an incremental net monetary benefit of £26 million per 100 000 population. Results were sensitive to reporting serious adverse events, excluding health service use, and including all participant costs. Conclusions Postal delivery of a pedometer intervention in primary care is cost-effective long term and has a 50% chance of being cost-effective, through resource savings, within 1 year. Further research should ascertain maintenance of the higher levels of PA, and its impact on quality of life and health service use. Trial registration number ISRCTN98538934; Pre-results.

Primary care pedometer-based walking intervention: mixed-methods results from 3 year follow-up of PACE-UP cluster-randomised controlled trial

Abstract Background Maintenance of physical activity is important for health, but few trials provide long-term objective data or qualitative evaluation of factors affecting this maintenance. The PACE-UP three-arm (postal, nurse-support, control) primary care cluster-randomised controlled trial recruited 1023 adults aged 45–75 years into a 12 week pedometer-based intervention including a physical activity diary and handbook incorporating behaviour change techniques; controls received usual care. Recruitment was from Sept 1, 2012, to Oct 31, 2013. At 12 months, step-counts increased by around a tenth, and time in moderate-to-vigorous physical activity (MVPA) in bouts by around a third in postal and nurse-supported arms compared with control. Using a mixed-methods approach at 3 year follow-up of the PACE-UP cohort, we aimed to assess whether the intervention effects persisted. Methods Assessments were done between Oct 1, 2015, and Nov 30, 2016. Mean daily step-counts and total weekly minutes of MVPA in bouts of 10 min or more at 3 years were collected with 7 day GT3X+ accelerometry (Actigraph, Pensacola, FL, USA) for all trial arms. Outcomes were regressed on baseline values to estimate change in treatment groups compared with control. Sensitivity analysis assessed missing data effects. Semi-structured telephone interviews were conducted with 60 participants. Interviews were audio recorded, transcribed, and coded, and thematic analysis was performed. Ethics approval was given by the National Research Ethics Service Committee London (Hampstead). Findings 3 year follow-up with accelerometry was 67% (681/1023). Compared with controls, intervention groups maintained higher steps per day (postal 627 additional steps[95% CI 198–1056], p=0·004; nurse 670 [237–1102], p=0·002), and more total weekly minutes of MVPA in bouts (postal 28 [7–49], p=0·009; nurse 24 [3–45], p=0·03). Results were robust to sensitivity analyses. Most interviewees felt that PACE-UP had increased their awareness of their physical activity. Facilitators to physical activity maintenance included self-motivation, social-support, and maintaining good health, with poor health and lack of time as barriers. Interpretation At 3 year follow-up of PACE-UP, step-counts and bouts of MVPA persisted, with no difference between intervention groups, suggesting that a primary care pedometer intervention, delivered by post or with nurse support, could help address the public health physical inactivity challenge. Major future challenges are how to apply this kind of effective intervention widely in the population and how to transform perceived barriers into facilitators (eg, poor physical health). Funding National Institute for Health Research Health Technology Assessment Programme (project number HTA 10/32/02).

P86 Are process evaluation measures related to intervention outcomes in the pace-up primary care pedometer-based walking trial?

Background PACE-UP trial results demonstrated positive effects of a pedometer-based walking intervention on objective physical activity (PA) outcomes at 3 and 12 months in 45–75 year old primary care patients, in both postal and nurse-supported trial arms compared to controls. We explored associations between intervention implementation measures and change in PA outcomes. Methods In accordance with the MRC guidance and framework (2014), the methods were selected through a key function model. Three quantitative aspects of the process evaluation relating directly to PA outcomes at 12 months were identified to assess intervention implementation: nurse session attendance (dose); PA diary completion (fidelity); and pedometer use (fidelity). These were considered as independent variables in the multi-level models estimating the effectiveness of the intervention on PA outcomes (changes in step-counts and time in moderate-to-vigorous PA (MVPA) levels in ≥10 min bouts). Results Dose participants attending all 3 nurse sessions increased their step-count at 3 months by 961 steps more than those attending 0–2 sessions (95% CI 401–1520, p=0.001). Minutes of MVPA were also significantly increased by 64 (36, 92) at 3 months and by 28 (1, 54) at 12 months. Fidelity: both postal and nurse groups showed strong positive associations of diary return on step-count and minutes of MVPA at 3 months compared with those who didn’t return the diary: postal steps 1458 (854, 20161), nurse steps 873 (190, 1555), postal MVPA 64 (33, 94), nurse MVPA 47 (17, 75). These differences had decreased by 12 months, and only the postal group effects remained statistically significant: steps 1114 (538, 1689), MVPA 47 (17, 75). Regular pedometer use in the postal group was associated with higher step counts at 3 and 12 months: 1029 (383, 1675) and 606 (22, 1990) respectively. Regular pedometer use was not associated with PA outcomes in the nurse group. Discussion Process evaluation measures showed significant associations with most PA outcomes at 3 and 12 months. These were stronger for the postal than the nurse group for diary and pedometer use. We cannot infer causality from these results, but the strong associations between nurse appointments, diary return, pedometer use and PA outcomes suggests that they were important factors in enabling the trial changes observed. We have shown the MRC framework to be an effective tool for process evaluation of intervention implementation.

P98 From effective trial to NHS implementation: progressing the primary care Pedometer and consultation evaluation (PACE-UP) randomised controlled trial into routine practice

Background The MRC framework describing the development-evaluation-implementation process for phase III complex intervention trials has been extended to include implementation research. We present i) the effectiveness evaluation of the PACE-UP pedometer-based walking intervention and ii) an exploration of implementation planning in routine practice using this extended framework. Methods i) 1023 inactive 45–75 year old primary care patients were randomised to: usual care (338); postal pedometer intervention (339); nurse-supported pedometer intervention (346). Intervention groups received pedometers, 12-week walking programmes, and physical activity (PA) diaries. The nurse group were offered three PA consultations. The primary and main secondary outcomes were changes from baseline to 12-months in average daily step-counts and time in moderate-to-vigorous PA (MVPA) in ≥10 minute bouts, measured over 7 days by accelerometry. ii) the extended MRC framework was used for implementation planning: long-term follow-up and dissemination; implementation development; feasibility and piloting of implementation; and phase IV controlled studies. Results i) 956 (93%) provided outcome data. Baseline average daily step-counts for the whole cohort were 7479 (s.d. 2671) steps/day and average time in MVPA ≥10 minute bouts was 94 (s.d. 102) minutes/week. Both intervention groups significantly increased step-counts and MVPA compared to controls at 12 months, with no significant differences between interventions. Additional steps/day: postal 641 (95% CI: 328, 954), nurse-support 682 (95% CI: 371, 994); additional MVPA in bouts (minutes/week) postal 33 (95% CI: 17, 49), nurse-support 35 (95% CI: 19, 51). ii) Long-term follow-up is funded and in progress; dissemination is underway, including adoption by the local CLAHRC and liaison with national bodies such as Public Health England; funding for intervention development including mobile apps and online resources has been applied for; feasibility testing and piloting of different patient recruitment methods from primary care is planned locally through the CLAHRC; a funding application for a phase IV controlled evaluation study is being developed. Conclusion A primary care pedometer-based walking intervention in inactive 45–75 year olds was effective at increasing step-counts by approximately a tenth and time in MVPA in bouts by approximately a third. Nurse delivery had no greater effect on 12-month PA outcomes than simpler, resource-efficient postal delivery. A primary care postal pedometer intervention could help address the public health physical inactivity challenge. The MRC extended framework for implementation is helpful for structuring the complex implementation process required to translate research findings into practice.