Non-pharmacological therapies for patients with lymphangioleiomyomatosis: a systematic review and meta-analysis.

Five studies is very few, and every one of them was small, ranging from a single patient up to 58. There was no randomised trial at all, so the review cannot show that the exercise caused the improvement. Some of the pooled studies had no control group. Patients were compared with their own scores from before treatment, which means an improvement could come from practice with the walk test, day-to-day variation, or attention from staff rather than from the training. The authors state that the small samples give the review too little statistical power to detect small but real effects, which is one reason the confidence intervals around the pooled results are wide. Only exercise-based treatments were found. Despite the review setting out to cover surgical therapy, psychological counselling and nutritional support, no study reported results for any of them, so there is nothing here on those approaches. Follow-up ran from about 12 weeks to one year. In a chronic, progressive disease that may be too short to see whether benefits last. Quality of life was measured with different questionnaires in different studies, which the authors say makes the results hard to compare across studies. People with severe hypoxaemia (FEV₁ below 30%) were excluded from three of the studies, so the results do not tell you what happens in the most severely affected patients. One of the five included studies is a case report of one person, which the authors themselves excluded from the pooled analysis to avoid bias from single-case data.

The authors state that financial support was received for the work and/or its publication. The study was supported by an American Cancer Society Institutional Research Grant (#129819-IRG-21-049-61-IRG144), and that grant also paid the article processing charge. No individual author disclosures, and no statement that a company selling any of the treatments was involved, appear in the text supplied.

Do not read the 37-metre improvement as proof that exercise changes the course of LAM. Some of the pooled studies had no control group and simply compared patients with their own scores from before treatment, and none of the five studies was randomised, so the gain in walking distance could come from something other than the training. The review also has nothing to say about surgery, psychological support or diet, because no study reported on them.