標題: 腎功能下降與心血管結果惡化有關 [打印本頁] 作者: far 時間: 2009-12-9 11:10 標題: 腎功能下降與心血管結果惡化有關
作者：Laurie Barclay, MD
出處：WebMD醫學新聞
November 19, 2009 — 根據11月5日線上第1版美國腎臟學會期刊(Journal of the American Society of Nephrology)的兩篇研究結果，不論有無腎臟病，腎功能下降與心血管結果惡化及早逝有關。
【第一篇研究：由Shlipak醫師等人執行】
加州舊金山退伍軍人醫學中心的Michael G. Shlipak醫師與「Cardiovascular Health Study」這項研究的夥伴寫道，以某一特定時間點定義，慢性腎臟病(Chronic kidney disease，CKD)是心血管疾病的一個重要風險因素，腎功能衰退率是否會造成額外的心血管風險則未知。
研究限制包括，估計腎絲球過濾速率正常範圍採用「Modification of Diet in Renal Disease」公式，可能會因此低估，評估後續變化的公式不精確、肌酸酐值隨著時間隨機波動、缺乏第1次和第2次就診的白蛋白尿資料、估計腎絲球過濾速率小於60 mL/minute/1.73 m2的病患數相對較少、可能有其他干擾因素。
國家心臟肺臟與血液研究中心支持「Atherosclerosis Risk in Communities S tudy (Matsushita醫師等人)」這項研究。有些研究作者接受Japan Society for the Promotion of Science；國家健康研究中心/國家糖尿病與消化道和腎臟病研究中心；或國家健康研究中心/國家心臟肺臟與血液研究中心等支持。
兩篇研究的作者群皆宣告沒有相關財務關係。
J Am Soc Nephrol. 線上發表於2009年11月5日。
Declining Renal Function Linked to Worse Cardiovascular Outcomes
By Laurie Barclay, MD
Medscape Medical News
November 19, 2009 — Declining renal function is linked to worse cardiovascular outcomes and early death in individuals with or without kidney disease, according to the results of 2 studies reported in the November 5 Online First issue of the Journal of the American Society of Nephrology.
First Study: Shlipak and Colleagues
"Chronic kidney disease (CKD), defined at a specific time point, is an important risk factor for cardiovascular disease," write Michael G. Shlipak, MD, MPH, from the San Francisco Veterans Affairs Medical Center in San Francisco, California, and colleagues from the Cardiovascular Health Study. "Whether the rate of kidney function decline contributes additional cardiovascular risk is unknown."
The investigators compared the associations of changes in renal function during the first 7 years vs incidence rates during the next 8 years for heart failure, myocardial infarction, stroke, and peripheral arterial disease.
Cystatin C–based estimated glomerular filtration rate (GFR) was assessed at baseline, year 3, and year 7, with rapid decline defined as more than 3 mL/minute/1.73 m2 per year. Rapid decline in kidney function occurred in 1083 (25%) of 4378 eligible participants. These individuals had a significantly higher incidence of each type of cardiovascular event (all P < .001).
Rapid decline in renal function was significantly associated with heart failure (adjusted hazard ratio [HR], 1.32; 95% confidence interval [CI], 1.13 - 1.53), myocardial infarction (HR, 1.48; 95% CI, 1.21 - 1.83), and peripheral arterial disease (HR, 1.67; 95% CI, 1.02 - 2.75) but not with stroke (HR, 1.19; 95% CI, 0.97 - 1.45), after multivariate adjustment for demographic factors, risk factors for cardiovascular disease, and baseline renal function. The presence or absence of CKD did not alter the association of rapid decline with each outcome.
"Declining kidney function associates with higher risk for HF [heart failure], MI [myocardial infarction], and PAD [peripheral arterial disease] among patients with or without CKD," the study authors write.
Limitations of this study include inability to determine causal relationships, indirect measurements of kidney function performed no more than 3 times during 7 years of follow-up, and lack of baseline measurements of albuminuria.
"If replicated in future studies, then these findings suggest that interventions to stabilize kidney function over time could have the additional benefits of decreasing CVD [cardiovascular disease] risk," the study authors conclude. "Future studies should consider not only static measures of kidney function but also ongoing changes in function to appreciate fully the cardiovascular consequences of kidney disease."
Second Study: Matsushita and Colleagues
The second study, by Kunihiro Matsushita, MD, PhD, from Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland, and colleagues, examined whether 3- and 9-year changes in estimated GFR are associated with the risk for coronary heart disease and all-cause mortality. The study cohort consisted of 13,029 participants of the Atherosclerosis Risk in Communities Study, a population-based sample of individuals aged 45 to 64 years who were observed from 1987 to 2006.
The risk for coronary heart disease and all-cause mortality were significantly greater in the quartile of participants with the greatest annual decline (? 5.65%) in estimated GFR vs the third quartile (annual decline between 0.33% and 0.47%), after adjustment for baseline covariates including estimated GFR in Cox proportional hazards models. The HR was 1.30 for coronary heart disease (95% CI, 1.11 - 1.52) and 1.22 for all-cause mortality (95% CI, 1.06 - 1.41). Findings were similar for analysis by 9-year changes in estimated GFR. Adjustment for covariates at the second estimated GFR measured attenuated the association with coronary heart disease but not with mortality.
An increase in estimated GFR during the first 3 years among participants with stage III CKD was also associated with higher mortality risk, which the authors attributed to possible clinical instability.
"A steeper than average decline in eGFR [estimated GFR] associates with a higher risk for coronary heart disease and all-cause mortality," the study authors write. "Increases in eGFR among participants with chronic kidney disease associate with similar increased risks....Our results suggest there may be clinical value in sequential kidney function data, often measured in routine care, even among individuals with mildly reduced kidney function."
Limitations of this study include underestimation by the Modification of Diet in Renal Disease equation of estimated GFR in the normal range, imprecision of the equation in evaluating sequential changes, random fluctuations in creatinine levels with time, lack of albuminuria measurement at visits 1 and 2, relatively few participants with estimated GFR of less than 60 mL/minute/1.73 m2, and possible residual confounding.
"The significant association between change in kidney function and risk for clinical outcomes after adjustment for covariates at follow-up suggests the observed effect is independent of the deterioration in traditional risk factors," the study authors conclude. "These data assist in the interpretation of serial serum creatinine measurements, often available in outpatient care, by indicating that change in eGFR contributes additional prognostic information beyond single eGFR measurement."
The study by Shlipak and colleagues was supported by an American Heart Association Established Investigator Award.
The Atherosclerosis Risk in Communities Study (Matsushita and Colleagues) is a collaborative study supported by the National Heart, Lung, and Blood Institute. Some of the study authors were supported by the Japan Society for the Promotion of Science; the National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases; or the National Institutes of Health/National Heart, Lung, and Blood Institute.
The authors of both studies have disclosed no relevant financial relationships.
J Am Soc Nephrol. Published online November 5, 2009.
