VALIDATION OF AGE-SPECIFIC KOREAN CUTOFF VALUES FOR ECHOCARDIOGRAPHIC LEFT VENTRICULAR HYPERTROPHY IN A KOREAN RURAL POPULATION

Abstract

For left ventricular hypertrophy (LVH), the genetic or ethnic difference in left ventricular response to hemodynamic and/or humoral stress is suggested. Recently, new cut-off values to diagnose LVH which are specific to age and sex categories. It is largely unknown how age and gender affect the prevalence of LVH in general population.

Design and Method: For 2295 subjects living in rural area, Yangpyeong County, Gyunggi-do, South Korea, who do not taking antihypertensive medication were analyzed. Cut-off values to diagnose LVH by mean + 2SD were 97/89 g/m² for 40 s, 101/100 g/m² for 50 s, 104/105 g/m² for 60 s, and 106/109 g/m² for 70 s for male and female, respectively. Local sex specific criteria for LVH were 117/105 g/m² for male and female, respectively.

Results: Age was categorized as 192/252/33/178 (n = 959) in male and 363/358/429/186 (n = 1336) in female for 40 s/50 s/60 s/70 s, respectively. Systolic blood pressure (BP) and diastolic BP were 121.6 ± 16.9/77.7 ± 11.5mmHg and BMI was 24.2 ± 3.1 kg/m². Hypertension was noticed in 19.5% and obesity was 39.5%. The prevalence of LVH were 47.9%/48.0%/38.5%/35.9% in male (p = 0.0135, p for trend = 0.0026) and 33.3%/24.0%/32.8%/31.7% in female for their 40 s/50 s/60 s/70 s (p = 0.02, p for trend = 0.79), respectively. By local criteria, LVH were noticed in 14.1%17.1%/15.7%/21.3% in male (p = 0.26) and 9.9%/14.8%/32.8%/39.2% in female (p < 0.0001, p for trend < 0.0001) for age categories. In multiple regression analyses, male(OR:1.605), eGFR(OR:1.020), hypertension(OR:2.125), and obesity(OR:1.551) were significant factors for LVH but age was not independent factors. These results were contrasted with the results by sex-specific criteria where age was independent factor for LVH. ORs for LVH were 1.576, 3.357, and 5.212 for their 50 s/60 s/70 s compared to 40 s.

Conclusions: New age specific Korean cut-off values for LVH seems to be valid in adjusting the effect of age on the prevalence of LVH. And our study also suggests that the difference in the prevalence from LVH by locally determined criteria should be overcome by outcome driven criteria for LVH.