"CPAP cures metabolic syndrome" paper in NEJM: retracted!

In early 2012, PulmCCM breathlessly reported the results of a New England Journal of Medicine (NEJM) paper by Surenda K. Sharma et al, claiming to show that continuous positive airway pressure (CPAP) can reverse metabolic syndrome (obesity, dyslipidemia, and insulin resistance).

Whoops. The authors retracted the article after keen-eyed academics smelled something fishy and asked to see the primary data. Sharma et al couldn't produce it, citing "transcription errors" as the source of incorrect data in key tables asserting differences between CPAP and sham groups in abdominal fat and carotid intima-medial thickness.

The original paper reported a dramatic reversal of metabolic syndrome among 11 of 86 patients treated with CPAP therapy, compared to only 1 of 86 treated with sham therapy.

Dr. Suzanne Bertisch and colleagues at Harvard Medical School asked for additional unpublished supporting data, which Sharma et al provided. "[T]he data they produced gave credence to our concerns, and I was somewhat surprised how fully they disclosed these data," Dr. Bertisch told MedPage Today. "It suggested to me that they didn't fully understand our concerns." That led to a request to see the primary data, which had gone mysteriously missing.

Sharma et al of the All India Institute of Medical Sciences in New Delhi wrote apologetically in the October 31, 2013 NEJM:

We regret to report that transcription errors occurred ... There were multiple errors in the table on pages 18 and 19 of the Supplementary Appendix concerning data on the accumulation of abdominal fat as assessed with the use of computed tomography and on carotid intima–media thickness as assessed with the use of ultrasonography. These errors, in turn, changed some values in Table 4 of the article. Although these changes do not alter the conclusions of the article, the primary data could not be located to verify corrections made from secondary tables. Accordingly, we have no way of confirming the correct data and, with regret, wish to retract the article.

The Sharma CPAP paper in NEJM was cited 69 times before being discredited. NEJM retracted another major paper in 2011 by Anil Potti, MD et al. Potti resigned from Duke University amid suspicion of academic dishonesty, and has since corrected or retracted 18 papers.

Retraction: CPAP for the Metabolic Syndrome in Patients with Obstructive Sleep Apnea. N Engl J Med 2011;365:2277-86.