ABSTRACT
BACKGROUND: Obesity is a major public health epidemic and is associated with increased risk of heart failure and mortality. We evaluated the impact of body mass index (BMI) on the prevalence of diastolic dysfunction (DD). METHODS: We reviewed clinical records and echocardiogram of patients with baseline echocardiogram between 1996 and 2005 that showed normal left ventricular ejection fraction (LVEF). Diastolic function was labeled as normal, stage 1, stage 2 or stage 3/4 dysfunction. Patients were categorized as normal weight (BMI <25 kg m(-2)), overweight (25-29.9 kg m(-2)), obese (30-39.9 kg m(-2)) and morbidly obese (î¶40 kg m(-2)). Multivariable ordinal and ordinary logistic regression were performed to identify factors associated with DD, and evaluate the independent relationship of BMI with DD. RESULTS: The cohort included 21 666 patients (mean (s.d.) age, 57.1 (15.1); 55.5% female). There were 7352 (33.9%) overweight, 5995 (27.6%) obese and 1616 (7.4%) morbidly obese patients. Abnormal diastolic function was present in 13 414 (61.9%) patients, with stage 1 being the most common. As BMI increased, the prevalence of normal diastolic function decreased (P<0.0001). Furthermore, there were 1733 patients with age <35 years; 460 (26.5%) and 407 (23.5%) were overweight and obese, respectively, and had higher prevalence of DD (P<0.001). Using multivariable logistic regression, BMI remained significant in both ordinal (all stages of diastolic function) and binary (normal versus abnormal). Also, obesity was associated with increased odds of DD in all patients and those aged <35 years. CONCLUSIONS: In patients with normal LVEF, higher BMI was independently associated with worsening DD.
ABSTRACT
AIM: Left ventricular (LV) ejection fraction (EF) and perfusion defect size (PDS) provide independent and incremental prognostic information in patients with coronary artery disease (CAD). The purpose of this study was to examine the correlation between EF and PDS. METHODS: LVEF and PDS were measured in 96 consecutive patients with CAD and abnormal perfusion scan using well-validated automated programs. The PDS was expressed as % of LV myocardium as total (reversible plus fixed), fixed or reversible. RESULTS: The EF was 49±15% (range 17-84), the total PDS was 29±15% (2-77) and the fixed PDS was 20±13% (2-58). The end-diastolic volume (EDV) was 131±59 mL (29-342) and end-systolic volume (ESV) was 72±51 mL (4-283). There were moderate but significant correlations between EF and total PDS (r=-0.46, P<0.0001) and fixed PDS (r=-0.45, P<0.0001) but not with reversible PDS. In the subgroup analysis, the correlations were stronger in patients with history of prior coronary artery bypass grafting than without, and higher in men than women. The highest correlations were seen between EF and EDV in both men and women (r=-0.68 and -0.74 respectively, P<0.0001 each), and between EF and ESV (r =-0.80, P<0.0001). CONCLUSION: Although there is a statistically significant correlation between PDS and EF, the correlation is not strong. This observation provides supportive evidence of why PDS and EF provide incremental prognostic information. It also supports the incremental prognostic merits of LV volume measurements.
