Yu-Hsuan Lin1, Dana Glei2, Maxine Weinstein2, Shiow-Ing Wu3, Kuo-Liong Chien4. 1. Health Promotion Administration, Ministry of Health and Welfare, Taipei, Taiwan; Institute of Epidemiology and Preventive Medicine, National Taiwan University, Taipei, Taiwan. 2. Center for Population and Health, Georgetown University, Washington, DC, USA. 3. Food and Drug Administration, Ministry of Health and Welfare, Taipei, Taiwan. 4. Institute of Epidemiology and Preventive Medicine, National Taiwan University, Taipei, Taiwan. Electronic address: klchien@ntu.edu.tw.
Abstract
BACKGROUND/ PURPOSE: Interleukin-6 (IL-6) and C-reactive protein (CRP) are inflammatory makers of potential interest in all-cause and cardiovascular death risk prediction, but their additive explanatory value to established risk factors is not well documented among nonwestern populations. METHODS: We investigated the additive value of IL-6 and CRP to the Framingham risk score and lifestyle factors in predicting all-cause and cardiovascular mortality among a population-representative sample of 1023 adults aged 54 years and above in Taiwan. RESULTS: A total of 351 deaths and 82 cardiovascular deaths were identified (median follow-up = 11.2 years). After adjustment for established risk factors, elevated IL-6 and CRP levels were associated with a higher risk of all-cause death: the hazard ratios for the highest risk quartile compared with the lowest quartile were 3.64 (95% confidence interval, 2.44-5.44) for IL-6 and 2.31 (95% confidence interval, 1.62-3.29) for CRP. IL-6 was also significantly associated with cardiovascular mortality. For both all-cause and cardiovascular mortality, IL-6 yielded a substantial and significant increase in the area under the receiver operator characteristic curve (change in the area under the receiver operator characteristic curve = 0.036 and 0.024, respectively), but CRP did not (change in the area under the receiver operator characteristic curve = 0.004 and 0.009, respectively). CONCLUSION: Although both IL-6 and CRP were significantly associated with all-cause mortality, only IL-6 provided a substantial improvement in discrimination. Similarly, IL-6 demonstrated a notable prognostic value for predicting cardiovascular mortality, but not CRP. These findings provide further support for the role of inflammation in the deterioration of health at older ages among a nonwestern population.
BACKGROUND/ PURPOSE:Interleukin-6 (IL-6) and C-reactive protein (CRP) are inflammatory makers of potential interest in all-cause and cardiovascular death risk prediction, but their additive explanatory value to established risk factors is not well documented among nonwestern populations. METHODS: We investigated the additive value of IL-6 and CRP to the Framingham risk score and lifestyle factors in predicting all-cause and cardiovascular mortality among a population-representative sample of 1023 adults aged 54 years and above in Taiwan. RESULTS: A total of 351 deaths and 82 cardiovascular deaths were identified (median follow-up = 11.2 years). After adjustment for established risk factors, elevated IL-6 and CRP levels were associated with a higher risk of all-cause death: the hazard ratios for the highest risk quartile compared with the lowest quartile were 3.64 (95% confidence interval, 2.44-5.44) for IL-6 and 2.31 (95% confidence interval, 1.62-3.29) for CRP. IL-6 was also significantly associated with cardiovascular mortality. For both all-cause and cardiovascular mortality, IL-6 yielded a substantial and significant increase in the area under the receiver operator characteristic curve (change in the area under the receiver operator characteristic curve = 0.036 and 0.024, respectively), but CRP did not (change in the area under the receiver operator characteristic curve = 0.004 and 0.009, respectively). CONCLUSION: Although both IL-6 and CRP were significantly associated with all-cause mortality, only IL-6 provided a substantial improvement in discrimination. Similarly, IL-6 demonstrated a notable prognostic value for predicting cardiovascular mortality, but not CRP. These findings provide further support for the role of inflammation in the deterioration of health at older ages among a nonwestern population.