Is chronic kidney disease associated with an increased prevalence of valvular and annular calcification in a community-based cohort?
In a community-based cohort, mild-to-moderate chronic kidney disease is independently associated with an increased prevalence of mitral annular calcification prior to the onset of end-stage renal disease.
Valvular calcification is common in the setting of end-stage kidney disease and is associated with increased risks for cardiovascular disease events. It is unknown whether the prevalence of valvular calcification is increased in milder kidney disease after accounting for cardiovascular risk factors. Participants who attended the sixth examination of the Framingham Offspring Study (1995 to 1998) were eligible. Kidney function was estimated by GFR using the simplified Modification of Diet in Renal Disease Study equation. Mitral annular calcification (MAC), aortic sclerosis, and aortic annular calcification were assessed by two-dimensional echocardiography. Logistic regression was used to examine the odds of valvular calcification among participants with chronic kidney disease (CKD; GFR < 60 ml/min per 1.73 m(2)). A total of 3047 participants (52% women; mean age 59 +/- 10 yr) were available for analysis. CKD was present in 8.6% (n = 262) of the sample. Among participants with valve/annular calcification (n = 284; 9.3%), 20% had CKD, compared with 7% in patients without valvular calcification. After adjustment for age, gender, systolic and diastolic BP, hypertension treatment, total/HDL cholesterol, body mass index, diabetes, smoking status, and cardiovascular disease, participants with CKD had a 60% increased odds of MAC (odds ratio 1.6; 95% confidence interval 1.03 to 2.5). There was no significant association between CKD and either aortic sclerosis or aortic annular calcification (odds ratio 1.1 and 1.1, respectively). After age and gender adjustment, the combination of both CKD and MAC was associated with a three-fold increased risk for death compared with those with neither condition (P = 0.0004). In the community, CKD is associated with presence of MAC before the onset of ESRD. Further research is warranted to understand whether traditional and novel vascular risk factor burden, as well as metabolic derangements found in early kidney disease, can account for the CKD-MAC association.
Fox et al. (2005) studied this question.