New Proposal for Adlt's Normal Sinus Heart Rates

BACKGROUND: The normal sinus heart rate standard of 60 to 100 beats per minute was set by the NYHA(New York Heart Association) in 1928. It has long been accepted to physicians, but clinical studies and experience suggest that both these limits are too high. Thus we reexamined to define operationally normal sinus heart rate that are scientifically and clinically acceptable. METHODS: Total 1,930 subjects(aged 20 to 92 years) were analyzed and evaluated for age, sex, body mass index(BMI), systolic blood pressure, diastolic blood pressure, and resting heart rates by electrocardiogram. We used Pearson's correlation test and t-test to analyze these data. RESULTS: Among 1930 subjects, 982 cases were male(51%) and 948 cases were female (49%), whose mean age was 48 years in male and 51 years in female. For the entire sample, mean heart rate and standard deviation was 68 +/- 11 beats/min. There was statistically significant difference between male(67+/-11 beats/min) and female(68+/-10 beats/min)(P<0,05). The prevalence of sinus tachycardia and bradycardia, calculated by current normal standard of 60 to 100 beats/min, was 22.0% (424 cases) and 0.9% (18 cases). Mean +/- two standard deviation yields rounded extremes of 46 to 89 beats/min for normal sinus heart rate. A positive correlations between resting heart rate and age(r=0.11), systolic blood pressure(r =0.17), diastolic blood pressure(r=0.12) were found(P<0.01). CONCLUSIONS: Two extremes of the normal sinus heart rate standard of 60 to 100 beats/min are set too high. They result in lower sensitivity for tachycardia and lower specificity for bradycardia. We propose that normal range for sinus heart rate should be 50 to 90 beats/min which is statistically justified, more realistic for clinical investigation.

Seropositivity of Anti-HCV in Intravenous drug abusers

BACKGROUND: From 1980s the methamphetamine(phillopon) was suddenly spread to our country and it becomes a serious social problem. Although the proportion of transfusion associated hepatitis C declined after introduction of Anti-HCV assay as screening test of blood donors, the overall prevalence of hepatitis C has remained the same, primarily because of increase of the proportion of hepatitis C patients among intravenous drug abusers. So we studied about prevalence of Anti-HCV, and other viral infectious disease transmission by intravenous drug abuse. METHODS: Total 202 drug abusers who had been admitted to Taegu Medical Center in 1994-1996 were tested for the presence of Anti-HCV. Epidemiologic data and histories related to drug use were obtained, as were serum test for hepatitis B, aminotransferase, HIV. RESULTS: The overall seropositivity of anti-HCV was 79.2%. Patients In HCV positive group were significant old age(34.0 yrs) and had long duration of injection(3.0 yrs) and the number of patient who had elevated aminotransferase level were significantly more than HCV negative group(p<0.05). No significant difference in sex, prevalence of HBs Ag and Anti HBc were observated between HCV positive group and negative group. The prevalence of Anti HBc was 52.1% and HBs Ag was 4.2%, but anyone was not detected for AIDS. CONCLUSIONS: The seropositivity of Anti-HCV in intravenous drug users in Taegu, Korea was 79.2%, comparable to that in Europe and U.S.A. This finding suggest that its time to hurry up for medical and public walfare service personal to concern and education of drug abusers, and inview of preventive medical care the need of general public information and education is pressing.