The urine albumin-creatinine ratio is a predictor for incident long-term care in a general population

<div><p>Background</p><p>Several types of cardiovascular diseases (CVDs) impair the physical and mental status. The purpose of this study was to assess the predictive ability of several cardiovascular biomarkers for identifying the incidence of disability as future recipients of public long-term care (LTC) service.</p><p>Methods</p><p>The subjects of this study were community-dwelling elderly individuals ≥ 65 years of age without a history of CVD (n = 5,755; mean age, 71 years). The endpoint of this study was official certification as a recipient of LTC. The cohort was divided into quartiles (Qs) based on the levels of three CVD biomarkers: the urinary albumin-creatinine ratio (UACR), plasma B-type natriuretic peptide concentration (BNP), and serum high-sensitivity C-reactive protein concentration (hsCRP). A time-dependent Cox proportional hazard model was used to determine the multi-adjusted relative hazard ratios (HRs) for incident LTC among the quartiles of each biomarker.</p><p>Results</p><p>During the follow-up (mean 5.6 years), 710 subjects were authorized as recipients of LTC. The HR was only significantly increased in the higher Qs of UACR (Q3, p < 0.01; Q4, p < 0.001). However, other biomarkers were not significantly associated with the endpoint. The risk predictive performance for the incidence of LTC as evaluated by an essential model (i.e. age- and sex-adjusted) was significantly improved by incorporating the UACR (net reclassification improvement = 0.084, p < 0.01; integrated discrimination improvement = 0.0018, p < 0.01).</p><p>Conclusions</p><p>These results suggest that an increased UACR is useful for predicting physical and cognitive dysfunction in an elderly general population.</p></div

Cox regression analyses for the risk of interim CVD for each biomarker.

<p>Cox regression analyses for the risk of interim CVD for each biomarker.</p

Change in the risk classification for the probability of needing long-term care using the base model compared with the base + UACR model.

<p>Change in the risk classification for the probability of needing long-term care using the base model compared with the base + UACR model.</p

A comparison of the baseline characteristics between the LTC and non-LTC groups.

<p>A comparison of the baseline characteristics between the LTC and non-LTC groups.</p

A time-dependent Cox regression analysis for the risk of LTC for each biomarker.

<p>Hazard ratios (95% confidence intervals) for the risk of LTC with each biomarker adjusted by age, sex, body mass index, systolic blood pressure, total cholesterol, high-density lipoprotein cholesterol, blood hemoglobin, HbA1c, eGFR, the duration of education, atrial fibrillation, smoking status, drinking status, and interim CVD. The solid line is the hazard ratio, the bar is the 95% confidence interval. The levels of quartiles for each biomarker are shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195013#pone.0195013.t001" target="_blank">Table 1</a> (see median and IQR).</p

Map of the study area.

<p>The black zone indicates the study area, including Kuji and Ninohe in northern Iwate Prefecture, northeast of Honshu, Japan. The population was 131,341 in the study area at the baseline survey (2002).</p

Flow chart of the procedure used to select participants for this study.

<p>The UACR, BNP, and hsCRP were measured in 15,262 participants living in the Ninohe and Kuji districts between 2002 and 2005. Among those participants, those < 65 years of age, who had a history of cardiovascular diseases (stroke, myocardial infarction or heart failure), who were already receiving LTC, or who lacked at least 1 variable for this study analysis were excluded. The final number of subjects in this study was 5,755.</p