Persistent elevation of C-reactive protein and ischemic heart disease in continuous ambulatory peritoneal dialysis patients

We-evaluated the association between a persistent elevation of C-reactive protein (CRP) level and the presence or severity of ischemic heart disease (IHD) in continuous ambulatory peritoneal dialysis (CAPD) patients. Seventy-three patients, who were over 40 years old, underwent dipyridamole thallium single photon emission computed tomography (SPECT) and followed-up for more than I year were enrolled. We measured stored plasma for CRP every 3 months. "Elevation" of CRP was defined as greater than or equal to 5 mg/L and "persistent elevation" of CRP as elevated CPR levels that lasted longer than 6 months. Serum albumin, cholesterol, lipoprotein(a), and plasma fibrinogen were measured at 3 months after the start of CAPD. Twenty-six patients showed an elevation of CRP for more than 6 months during the follow-up period. Twenty-eight patients showed positive findings on thallium. SPECT. Coronary angiography showed significant. stenosis (narrowing of the diameter more than 50%) in 23 out of the 25 patients studied. Seventeen (65%) out of 26 patients who had an elevated CRP level for longer than 6 months had positive thallium SPECT. The presence of diabetes, albumin, fibrinogen, and the presence of a persistent elevation of CRP were different between the patients with positive (n=28) or negative thallium SPECT (n=45). A multivariate logistic regression analysis showed that a persistent elevation of CRP is the only predictor of positive thallium SPECT (p=0.002). There was a tendency of association, although it was not statistically significant between the persistence of CRP elevation and the severity of IHD (p=0.066). Three out of 9 patients who had a persistent elevation of CRP and a negative thallium SPECT had a history of cerebral infarction or peripheral vascular disease. Therefore, 77% (20/26) of an elevated CRP level that lasted longer than 6 months can be explained by the presence of IHD or other atherosclerotic vascular disease. In conclusion, a persistent elevation of CRP level in CAPD patients was strongly. associated. with IHD. For patients who have a persistent elevation of CRP without apparent cause of it, we recommend a workup for IHD or other atherosclerotic cardiovascular disease.