Abstract Body (Do not enter title and authors here): Background: Obesity increases the risk of sudden cardiac death (SCD) in the general population, but in patients with CAD, obesity has been associated with a smaller risk of death. This ‘obesity paradox’ is confounded by several factors and the association between weight gain and the risk of SCD in CAD is unclear.
Aim: We aimed to investigate the effect of weight gain on the risk of SCD in a prospective cohort of CAD patients.
Methods: We have prospectively enrolled 1,946 patients with CAD (mean age 66.9±8.6, 68% male), with a mean follow-up of 8.7±2.2years. Weight was measured at baseline and at 5 years and was classified into 3 groups: 1) -5%< weight change <+5% (reference group), 2) weight gain >5%, and 3) weight loss >5%. The primary endpoint was SCD or resuscitation from sudden cardiac arrest. Non-sudden cardiac death and non-cardiac death were secondary endpoints. Statistical analysis was performed with Cox regression and was adjusted for age, sex, baseline BMI, type 2 diabetes, kidney function (eGFR), and left ventricle ejection fraction.
Results: A total of 1,053 subjects had weight measured at baseline and at 5 years. Thirteen percent (13%) gained weight >5% and 19% lost weight >5% in 5 years. During a mean follow-up of 2.1±0.7 years after the second weight measurement, SCDs/SCAs occurred in 18 patients. Weight gain was associated with an increased risk of SCD (HR 3.54, 95% CI 1.17-10.67; p=0.03), but not with non-cardiac death (HR 2.01, 95% CI 0.97-4.19; p=0.06) or non-sudden cardiac death (no events). Weight loss was associated with an increased risk of non-sudden cardiac death (HR 2.74, 95% CI 1.07-6.97; p=0.04) and non-cardiac death (HR 2.60, 95% CI 1.40-4.81; p=0.002) but not with SCD (HR 1.73, 95% CI 0.51-5.86; p=0.38).
Conclusions: Weight gain was associated with an increased risk of SCD but not with other modes of death. Patients with stable weight had the best prognosis. These results suggest that weight changes may have a special effect on CAD trajectory and further studies are warranted to investigate the role of weight gain on SCD risk.