Dear Sir,

We read with great interest the article ‘Long-term effects of bariatric surgery on cardiovascular risk factors in Singapore’ by Panday et al,(1) in which the authors presented retrospective data with a five-year follow-up.

We agree that there is limited data on whether bariatric surgery leads to a sustained improvement in the lipid profile of patients in the long term. However, we have a few pertinent questions. First, the authors mentioned that 61 (58.7%) patients had preoperative hypertension, which is a crucial cardiovascular risk factor. We could not find the effect of bariatric surgery on hypertension in the follow-up data. Second, various studies have reported that Roux-en-Y gastric bypass is more effective for lowering lipid levels, and the authors also mentioned this point in the discussion.(2,3) In this study, 85 patients underwent sleeve gastrectomy and 16 patients underwent gastric bypass. It would be interesting to know whether the authors found any difference between the two procedures in terms of the lipid levels of the patients at the one- and five-year follow-ups.

Panday VB, Shabbir A, Kuntjoro I, et al. Long-term effects of bariatric surgery on cardiovascular risk factors in Singapore. Singapore Med J. 2021;62:472.
Buchwald H, Varco RL, Matts JP, et al. Effect of partial ileal bypass surgery on mortality and morbidity from coronary heart disease in patients with hypercholesterolemia –report of the Program on the Surgical Control of the Hyperlipidemias (POSCH). N Engl J Med. 1990;323:946-55.
Gleysteen JJ. Results of surgery:long-term effects on hyperlipidemia. Am J Clin Nutr. 1992;55:2 Suppl 591S-593S.