PMID 32807179

Research
All papers

High-intensity interval training and health-related quality of life in de novo heart transplant recipients - results from a randomized controlled trial

Rolid K, Andreassen AK, Yardley M, Gude E, Bjørkelund E, Authen AR, Grov I, Pettersen KI, Dall CH, Karason K, Broch K, Gullestad L, Nytrøen K

Question

Does high-intensity interval training improve health-related quality of life more than moderate-intensity continuous training in de novo heart transplant recipients?

Summary

In recent heart transplant recipients, 9 months of supervised high-intensity interval training and moderate continuous training both improved physical quality-of-life scores. HIIT did not outperform moderate training for the main quality-of-life outcomes, but it produced a larger VO2peak gain and better extensor muscular exercise capacity. Adverse events and rejection rates were similar between groups.

Methodology

  • Seventy-eight heart transplant recipients were retested after 9 months; baseline groups were HIT n=37 and MICT n=41. Participants were recent de novo heart transplant recipients on immunosuppressive medication, with mean age about 49 years and about 73% men.
  • 78 participants.
  • Aerobic interval training plus strength training.
  • Work intervals: 2-4 intervals, progressing toward 4 min intervals.
  • Recovery: Active rest between intervals.
  • Intensity: HIT 85-95% maximal effort, RPE 16-18; active rest RPE 11-13.
  • Warm-up plus interval or continuous aerobic work plus cooldown and strength training.
  • 2-3.
  • 9 months.
  • Multicenter randomized controlled trial
  • SF-36v2 Physical and Mental Component Summary scores and subscales, Hospital Anxiety and Depression Scale, Visual analogue scales for general health and well-being, and VO2peak and muscular strength/exercise capacity were tracked.

Outcomes

SF-36 physical component

SF-36 Physical Component Summary improved within both groups: HIT 42.2 +/- 7.6 to 48.4 +/- 9.3 and MICT 43.2 +/- 7.7 to 49.0 +/- 8.4; no between-group difference in change (0.6, 95% CI -3.1 to 4.2; p=.762).

95% CI -3

No clear change

SF-36 role emotional

Role Emotional was the only HRQoL between-group difference favoring HIT: change difference 7.2, 95% CI 1.6 to 12.8; p=.012.

95% CI 1

Mixed

VO2peak

VO2peak improved more with HIT: +4.8 +/- 4.1 vs +3.1 +/- 3.5 mL/kg/min; difference 1.8, 95% CI 0.1 to 3.5; p=.044.

95% CI 0

Improved

Extensor muscular exercise capacity

Extensor muscular exercise capacity favored HIT with a between-group difference of 464, 95% CI 63 to 863; p=.024.

95% CI 63 to 863

Improved

Anxiety and depression

Anxiety and depression scores were low and did not meaningfully change.

No clear change

Insights

  • In medically supervised rehabilitation, HIIT can be feasible after heart transplant in selected recipients.
  • For quality of life, HIIT should not be framed as clearly superior to moderate training based on this trial.
  • Fitness gains may be larger with HIIT even when patient-reported physical quality-of-life scores improve similarly.

Limitations

  • Participants had relatively high baseline HRQoL and may represent healthier transplant recipients.
  • HRQoL was a secondary/prespecified endpoint and the sample may have been underpowered for some patient-reported outcomes.
  • Generic SF-36 may miss transplant-specific quality-of-life changes.
  • Findings are not generalizable to unsupervised exercise or high-risk transplant recipients.

Safety

  • No between-group differences were found in rejections, serious adverse events, or adverse events.
  • Exercise was supervised by health personnel and heart-rate monitored.