Masked Hypertension Determined by Self-Measured Blood Pressure at Home and Chronic Kidney Disease in the Japanese General Population: The Ohasama Study

Abstract

, Takayoshi OHKUBO 4), 5) , Masahiro KIKUYA 6) , Kei ASAYAMA 4), 5) , Ryusuke INOUE 5) , Haruhisa HOSHI 7) , Sadayoshi ITO 1) , and Yutaka IMAI 59.6 mL/min, and 57.3 mL/min for CCr, 4.2%, 8.9%, 10.3%, and 12.8% for the prevalence of positive proteinuria, and 2.3%, 3.0%, 6.3%, and 9.8% for the proportion with CCr <60 mL/min with proteinuria. Compared with the SNBP group, the MHT and SHT groups exhibited significant differences in these parameters (p <0.05, for each). The adjusted odds ratios for CCr <60 mL/min with proteinuria were significantly higher in the MHT (2.56) and SHT (3.60) groups compared with the SNBP group (reference IntroductionAccumulative evidence has revealed that a decreased glomerular filtration rate (GFR) and the presence of proteinuria are independent risk factors for death and/or cardiovascular disease (CVD) events among general populations (1-3). Thus, it is now recognized that chronic kidney disease (CKD) (4) is an emerging new target for investigation from the viewpoint of public health. Hypertension, a classic risk factor for CVD events, can be clinically classified into subgroups: sustained hypertension (SHT), white-coat hypertension (WCHT), and masked hypertension (MHT) (5), which is characterized by normal casual blood pressure (CBP) and elevated home blood pressure (HBP) or ambulatory blood pressure (BP) levels. Among the subtypes, it has been revealed that patients with MHT are at a high risk for CVD morbidity and mortality similar to that of patients with SHT (6, 7). Accordingly, it is clinically important to clarify the relationship between CKD and MHT in terms of screening high-risk populations and targeting therapeutic levels of BP in CKD patients; however, little is known regarding this issue.The present cross-sectional study examined the CKD incidence in subjects with MHT in the Japanese general population. Methods DesignThis study was a part of the Ohasama study, a longitudinal BP measurement project initiated in 1986. The socio-economic and demographic characteristics of this region and full details of the project have been described previously (8). The study was approved by the Institutional Review Board of Tohoku University School of Medicine and the Department of Health of the Ohasama Town Government. Study PopulationIn Japan, annual health checkups are available for farmers, the self-employed, retirees, and dependents aged ≥ 35 years. Among the 7,496 residents of Ohasama, 3,076 were eligible for annual health checkups in 1992. A total of 2,192 residents participated in checkups from 1992 to 1997. Of the 2,192 participants, 215 were excluded due to missing serum creatinine levels, missing dipstick tests for spot-urine, and other confounding factors (age, gender, body mass index [BMI], current smoking, diabetes mellitus, hypercholesterolemia, antihypertensive treatment, and history of CVD). Participants who were hospitalized, mentally ill, or bedridden were also excluded (n= 185). In addition, participants with less than 14 d of HBP measurements and participan...

Usefulness of assessing masked and white-coat hypertension by ambulatory blood pressure monitoring for determining prevalent risk of chronic kidney disease: the Ohasama study

“…7 We have also previously reported that MHT on the basis of HBP is significantly associated with creatinine clearance o60 ml min À1 with proteinuria when compared with SNBP in the general population. 13 Consistent with those findings, this study demonstrated that individuals with MHT on the basis of ABP showed a higher prevalence of proteinuria, eGFR o60 ml min À1 per 1.73 m 2 and CKD.…”

“…13 Of the 2013 residents who participated in checkups from 1992 to 1997, data on serum creatinine levels, dipstick test for spot urine and confounding factors were unavailable for 214 subjects. Of the remaining 1799 individuals, ABP measurements were recorded in 1073 participants.…”

“…In a recent study, we demonstrated that CKD risk of WCHT based on home BP (HBP) was no different from that of sustained normal blood pressure (SNBP). 13 Although several clinical studies have reported associations between ABP and CKD, 14,15 only limited information is available from the general population. The objective of this study was to examine CKD risk associated with WCHT and MHT, as determined by ABP monitoring.…”

The Japanese Society of Hypertension Guidelines for Self-monitoring of Blood Pressure at Home (Second Edition)

“…In the general population, the risk of chronic kidney disease has been reported to be high in patients with masked hypertension, as determined by home BP measurements. 148 In patients undergoing dialysis, the greatest prognostic factor is the presence of cerebroand cardiovascular complications, and the management of hypertension is extremely important. However, BP measured at the dialysis center fluctuates widely, and has been reported to not accurately reflect the outcome.…”

Home blood pressure monitoring, even by the elderly, may save a kidney

“…Several reports have shown that BP measured at home has superior predictive value for mortality, cardiovascular events 6 and stroke, 7,8 and screening value for asymptomatic cerebral ischemia 9 and CKD. 10 In addition, a previous study showed that home-measured BP is better than clinicmeasured BP at predicting the progression of disease in 'general' CKD patients. 11 In an article appearing in this issue, Okada et al 12 used home BP monitoring, and assessed the prognostic value of home BP (morning and evening) and casual BP for renal and cardiovascular outcome in elderly CKD patients (age X70 years).…”