Digital behavior change interventions to promote physical activity and/or reduce sedentary behavior in older adults: a systematic review and meta-analysis

Key points

1. 0122 studies involving 1757 older adults (mean age 67 years) were pooled
2. 02Moderate-to-vigorous physical activity increased by roughly 52 minutes per week
3. 03Sedentary time fell by roughly 58 minutes per day
4. 04Systolic blood pressure dropped by about 11 bpm and physical functioning improved
5. 05Effects on total physical activity were not sustained at follow-up in the two studies that measured it

How it was conducted

Design

Systematic review and random-effects meta-analysis following PRISMA guidelines (PROSPERO CRD42018090359)

Databases searched

MEDLINE, PsycINFO, EMBASE via OVID from inception to March 2018; grey literature via Google and Bing

Included study types

Randomised controlled trials (RCTs) and pre-post studies

Participants

Older adults aged 50 and over, including healthy adults and those with physical or mental health conditions

Intervention

Any digital behaviour change intervention (apps, wearables, websites, exergames, interactive phone systems) targeting physical activity or sedentary behaviour

Primary outcomes

Total physical activity, steps per day, moderate-to-vigorous physical activity (MVPA), and sedentary time

What they found

• Total physical activity (RCT end-of-intervention): SMD = 0.28; 95% CI 0.01, 0.56; p = 0.04; I2 = 47%
• Total physical activity (RCT follow-up): SMD = 0.11; 95% CI -0.14, 0.36; p = 0.39 (non-significant)
• Total physical activity (pre-post studies): SMD = 0.25; 95% CI 0.09, 0.41; p = 0.002
• MVPA (6 RCTs, n = 694): SMD = 0.47; 95% CI 0.32, 0.62; p < 0.001; I2 = 0%; MD = 51.97 min/week; 95% CI 23.91, 80.03
• Daily steps (6 RCTs end-of-intervention): SMD = 0.18; 95% CI -0.03, 0.38; p = 0.09 (non-significant); MD = 401 steps
• Sedentary time (5 RCTs): SMD = -0.44; 95% CI -0.69, -0.19; p < 0.001; I2 = 0%; MD = -58.49 min/day; 95% CI -100.34, -16.64
• Systolic blood pressure (3 RCTs): SMD = -0.14; 95% CI -0.35, 0.07; p = 0.18 (SMD non-significant); MD = -11.33 bpm; 95% CI -21.96, -0.71; p = 0.04
• Diastolic blood pressure: SMD = -0.10; 95% CI -0.30, 0.09; p = 0.30 (non-significant)
• Physical functioning (5 RCTs): SMD = 0.21; 95% CI 0.03, 0.40; p = 0.03; I2 = 0%
• Body weight (5 RCTs): SMD = -0.15; 95% CI -0.33, 0.03; p = 0.10 (non-significant)
• Quality of life (3 RCTs): SMD = 0.27; 95% CI -0.02, 0.57; p = 0.07 (non-significant)

Limitations

• Most studies were short-term (median 12 weeks) with few follow-up measurements, so long-term maintenance is unknown
• Many studies were feasibility studies with small sample sizes, which may inflate effect estimates
• Participants could not be blinded to intervention assignment in most studies, introducing performance bias
• The search excluded 'web-based', 'internet', and 'pedometer' terms to manage search volume, which may have missed eligible studies

Why it matters

For patients

Apps and wearables can meaningfully increase physical activity and cut sitting time in people aged 50 and over, with potential benefits for blood pressure and physical function, though benefits may fade once the programme ends.

For clinicians

Digital behaviour change interventions are a scalable option for promoting physical activity in older patients; interventions combining goal-setting, feedback, self-monitoring, and social support appear most common among effective programmes.

For readers

This is the first meta-analysis in this specific population and provides a solid initial evidence base, but the small number of follow-up studies and heterogeneous intervention types mean confidence in long-term effectiveness is limited.