Number needed to treat (NNT) is a simple and effective index for clinical therapeutic effect assessment worldwide accepted in recent years. By calculation of absolute risk reduction (ARR) of classified variables, it made the effect estimate reflect objectively the therapeutic effect of an intervention. However, clinical application of this index was introduced rarely in Chinese literature. With the examples from some published clinical reports, the calculation of NNT and its 95% confidence interval were demonstrated in this paper, and its application was illustrated by some relevant terms explanation and Meta-analysis methods introduction.
Confidence Intervals ; Humans ; Meta-Analysis as Topic ; Numbers Needed To Treat ; Outcome Assessment (Health Care) ; methods ; Treatment Outcome

Decompressive craniectomy is used to treat increased intracranial pressure due to brain swelling in middle cerebral artery infarction. Recently, 3 European multicenter, prospective, randomized trials and a pooled analysis were published. In the pooled analysis, decompressive craniectomy did not appear to increase the risk of complete dependency, misery, and hopelessness. Exactly 2 patients in the surgical and medical groups (5%) were bedbound and severely disabled (mRS 5) at 1 year. The proportion of patients alive with minimal-tomoderate disability (mRS 0-3), however, was significantly increased from 21% to 43%. Decompressive craniectomy resulted in a 49% absolute risk reduction in death, and an absolute increase in the proportion of patients rated as mRS 2 of 12%, mRS 3 of 10%, and mRS 4 of 29%. But, this can be applied in cases with relative young age and early surgical procedure. Therefore, the indication for decompressive craniectomy should be individualized and its potential implications on long-term outcomes should be comprehensively discussed with the caregivers.
Brain Edema ; Caregivers ; Cerebral Infarction ; Decompressive Craniectomy ; Dependency (Psychology) ; Humans ; Infarction, Middle Cerebral Artery ; Intracranial Hypertension ; Intracranial Pressure ; Numbers Needed To Treat

BACKGROUND: The management of risk factors of coronary heart disease is highly needed because the prevalence of ischemic heart disease is increasing in Korea. This study was aimed to evaluate the effects of periodic health examination on risk factors of coronary heart disease using Framingham Point Scores. METHODS: The medical records of 343 clients who underwent periodic health examination five times from January 1996 to December 2001 at one medical center in Seoul were reviewed. The five risk factor scores (age, total cholesterol, smoking, HDL-cholesterol, systolic blood pressure), total risk scores, absolute risk and the proportion of the high risk group and the obesity group were analyzed for all the periodic health examinations. RESULTS: For the five periodic health examinations, age risk factor score increased in men and women. Scores of risk factors such as smoking, total cholesterol, HDL-cholesterol and systolic blood pressure decreased in men only (P<0.0001). The total risk score (P<0.0001) and the absolute risk (P=0.0002) increased in men. The total risk score (P<0.0001) and the absolute risk (P=0.3238) increased in women with no changes of other risk factors except increased age score and decreased HDL-cholesterol score. The proportion of the high risk group (P=0.5406) and the obesity group (P=0.0762) were very small and not changed. CONCLUSION: The risk of coronary heart disease as not reduced with the five periodic health examinations. Therefore, the total risk score and the absolute risk did not decrease. Continuous risk factors management must be emphasized after periodic health examination for absolute risk reduction.
Blood Pressure ; Cholesterol ; Coronary Disease* ; Female ; Humans ; Korea ; Male ; Medical Records ; Myocardial Ischemia ; Numbers Needed To Treat ; Obesity ; Prevalence ; Risk Factors* ; Seoul ; Smoke ; Smoking

PURPOSE: Morbid obesity is a well-known risk factor for cardiovascular disease (CVD). This study aimed to quantitatively evaluate the effects of bariatric surgery on CVD risk reduction in Korean obese patients by using three CVD risk prediction models (Framingham General Cardiovascular Risk Score [FRS], Pooled Cohort Equation [PCE], and Korean Risk Prediction Model [KRPM]), and to investigate which procedure between laparoscopic Roux-en Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG) is a better option for CVD risk reduction. MATERIALS AND METHODS: We retrospectively reviewed all obese patients who underwent bariatric surgery at a single institution from October 2009 to May 2016. Of the 1034 patients reviewed, 83 patients (6.5%) who met the criteria for calculating the FRS, PCE, and KRPM scores and had a follow-up of at least 1 year were included in this study. RESULTS: The FRS, PCE, and KRPM scores were significantly decreased at postoperative 1 year (10.47±7.30% to 6.33±4.59%, P=0.000; 5.45±6.25% to 2.75±2.75%, P=0.000; and 4.53±2.96% to 3.49±2.13%, P=0.000, respectively) in LRYGB. The PCE and KRPM scores were significantly decreased (4.13±3.63% to 2.42±2.45%, P=0.004 and 4.14±1.95% to 3.22±1.94%, P=0.000, respectively) in LSG, but not the FRS (9.43±3.58% to 5.63±3.24%, P=0.118). There was no difference in absolute risk reduction in FRS, PCE, and KRPM between LRYGB and LSG (4.13±5.08% and 3.80±3.50%, P=0.788; 2.70±0.52% and 1.72±0.49%, P=0.799; and 1.03±1.85% and 0.92±0.97%, P=0.776, respectively). CONCLUSION: LRYGB and LSG can equally significantly decrease the CVD risk in the Korean population, based on FRS, PCE, and KRPM.
Bariatric Surgery ; Cardiovascular Diseases ; Cohort Studies ; Follow-Up Studies ; Gastrectomy ; Gastric Bypass ; Humans ; Numbers Needed To Treat ; Obesity, Morbid ; Retrospective Studies ; Risk Assessment ; Risk Factors ; Risk Reduction Behavior

PURPOSE: The 2013 American College of Cardiology (ACC)/American Heart Association (AHA) cholesterol management guidelines advocate the use of statin treatment for prevention of cardiovascular disease. We aimed to assess the usefulness of coronary artery calcium (CAC) for stratifying potential candidates of statin use among asymptomatic Korean individuals. MATERIALS AND METHODS: A total of 31375 subjects who underwent CAC scoring as part of a general health examination were enrolled in the current study. Statin eligibility was categorized as statin recommended (SR), considered (SC), and not recommended (SN) according to ACC/AHA guidelines. Cox regression analysis was employed to estimate hazard ratios (HR) with 95% confidential intervals (CI) after stratifying the subjects according to CAC scores of 0, 1–100, and >100. Number needed to treat (NNT) to prevent one mortality event during study follow up was calculated for each group. RESULTS: Mean age was 54.4±7.5 years, and 76.3% were male. During a 5-year median follow-up (interquartile range; 3–7), there were 251 (0.8%) deaths from all-causes. A CAC >100 was independently associated with mortality across each statin group after adjusting for cardiac risk factors (e.g., SR: HR, 1.60; 95% CI, 1.07–2.38; SC: HR, 2.98; 95% CI, 1.09–8.13, and SN: HR, 3.14; 95% CI, 1.08–9.17). Notably, patients with CAC >100 displayed a lower NNT in comparison to the absence of CAC or CAC 1–100 in SC and SN groups. CONCLUSION: In Korean asymptomatic individuals, CAC scoring might prove useful for reclassifying patient eligibility for receiving statin therapy based on updated 2013 ACC/AHA guidelines.
Aged ; American Heart Association ; Cardiovascular Diseases/*prevention & control ; Cause of Death ; Confidence Intervals ; Coronary Artery Disease/*diagnosis ; Female ; Humans ; Hydroxymethylglutaryl-CoA Reductase Inhibitors/*therapeutic use ; Male ; Middle Aged ; Numbers Needed To Treat ; Practice Guidelines as Topic ; Regression Analysis ; Republic of Korea ; Risk Assessment ; Risk Factors ; United States ; Vascular Calcification/*diagnosis