Impact of weight on long-term survival among patients without known coronary artery disease and a normal stress SPECT MPI

ArticleinJournal of Nuclear Cardiology 17(3):390-7 · March 2010with3 Reads
Impact Factor: 2.94 · DOI: 10.1007/s12350-010-9214-6 · Source: PubMed

    Abstract

    While obesity has been shown to be associated with a worse mortality, an "obesity paradox"--lower mortality in obese patients--has been noted among many patients with coronary artery disease (CAD). The extent to which an obesity paradox operates among patients with only suspected CAD, is not well determined.
    A total of 3,673 patients (60 +/- 13 years, 36% males) with no history of heart disease and a normal stress SPECT were included in this study. Normal weight was defined as BMI of 18.5-24.9 kg x m(2); overweight 25-29.9 kg . m(2), obese >30 kg x m(2). The baseline clinical risk factors were recorded for each patient. The end point of the study was all-cause mortality. Of patients 942 (26%) were normal weight, 1,261 (34%) were overweight, and 1,470 (40%) were obese. Mean patient follow-up was 7.5 +/- 3 years. When compared to normal weight patients (event rate 3.2%/year), there was a lower incidence of death in the overweight (event rate 1.5%/year, P < .0001) and the obese (event rate 1.2%/year, P < .0001) groups. After controlling for baseline risk factors, using a reference HR = 1 for normal weight patients, there was a lower risk of death in the overweight (HR = .54, 95% CI .43-.7) and the obese groups (HR = .49, 95% CI .38-.63).
    In patients without known cardiac disease and a normal stress SPECT, overweight and obese patients had a lower rate of all-cause mortality compared to normal weight patients over long-term follow-up. This study substantially extends the spectrum of patients in whom the obesity paradox is present.