Effects of home-based cardiac rehabilitation integrated in the cardiac care bridge transitional care program on the physical functioning of older patients who are frail: secondary analysis of a randomized trial.

Only 170 of the 306 randomised patients (55.6%) were still measurable at six months, so the main result comes from the patients well enough to be tested. The patients who dropped out were more frail: in the program group they were more likely to live alone and women had weaker grip strength, and in the usual care group they had lower starting SPPB scores and managed fewer steps. The people this trial says least about are the frailest ones. When the missing patients were put back into the analysis mathematically, the difference between groups fell to 0.5 points and was no longer statistically significant. The authors also found that how much data a patient was missing was itself related to the outcome, which means the patients who dropped out may have responded differently to the program. This was a secondary analysis of a trial that was not designed or powered to answer the physical functioning question, so a real difference may have been missed. How much of the program each patient actually received varied a lot. The median was four of nine planned sessions, and about half received fewer than five. Some of that was patient choice, but because the number of sessions did not relate to how well patients did, the exercise dose itself is not what clearly drove the result. The SPPB cannot register improvement in patients who already score well and can only move in whole points, and nobody with a low-risk starting score improved, which fits the known ceiling effect of the test. Follow-up was only six months, and the same trial's previously reported main outcomes found no reduction in hospital readmission or death and no cost-effectiveness benefit at one year.

The trial was funded by the Dutch Research Council and the Netherlands Organization for Health Research and Development (ZonMw), both public research funders. No author conflicts of interest or industry involvement are stated in the text supplied.

Do not read the 0.8-point gain as proof that home-based cardiac rehabilitation works for frail older patients. It rests only on the 170 of 306 patients who survived and completed testing at six months, and it was no longer statistically significant once the 44% of each group with no follow-up data were included. In the program group, 28% never received a single home-based rehabilitation session.