Yasuko Yamaguchi1,2, Takashi Takei3, Yoko Matsuda4, Wako Yumura3, Mitsuyo Itabashi3, Tomio Arai4, Akira Shimizu5. 1. Department of Analytic Human Pathology, Nippon Medical School, 1-1-5, Sendagi, Bunkyo-ku, Tokyo, 113-0022, Japan. yasuko.yamaguchi.tachibana@gmail.com. 2. Department of Nephrology, Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan. yasuko.yamaguchi.tachibana@gmail.com. 3. Department of Nephrology, Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan. 4. Department of Pathology, Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan. 5. Department of Analytic Human Pathology, Nippon Medical School, 1-1-5, Sendagi, Bunkyo-ku, Tokyo, 113-0022, Japan.
Abstract
BACKGROUND: The aim of this autopsy study was to clarify the differences of renal histopathology between non-chronic kidney disease (CKD) and CKD caused by hypertensive-nephrosclerosis in the elderly and during the aging process. METHODS: We examined autopsy specimens from 105 elderly patients (53 male subjects; mean age, 86.2 years) including 44 patients with CKD as a result of nephrosclerosis. The analysis was divided into two groups depending on whether they had CKD. RESULTS: The incidences of arterial intimal thickening (AIT), obsolescent-type global glomerulosclerosis (OB), and interstitial fibrosis and tubular atrophy (IF/TA) were higher in the CKD group than in the non-CKD group (all p < 0.01). These factors were all correlated with each other (AIT vs. OB, r = 0.43; AIT vs. IF/TA, r = 0.25; OB vs. IF/TA, r = 0.53). IF/TA had the strongest association with hypertension and decreased eGFR. In the non-CKD group, the frequency of OB was more than 20% in subjects aged 90 years or older. However, the individuals in the non-CKD group tended to have compensatory glomerular hypertrophy with increasing age and a retained eGFR, while the CKD group was unable to obtain compensatory hypertrophy and had a lower eGFR. We also found that AIT, OB and IF/TA occurred independently of systemic atherosclerosis. CONCLUSIONS: Non-CKD in the elderly refers to the so-called aging kidney. The progression from aging kidney to CKD caused by nephrosclerosis was influenced by increases in AIT, OB and IF/TA. IF/TA was thought to be the most important downstream factor in the progression of aging kidney to CKD.
BACKGROUND: The aim of this autopsy study was to clarify the differences of renal histopathology between non-chronic kidney disease (CKD) and CKD caused by hypertensive-nephrosclerosis in the elderly and during the aging process. METHODS: We examined autopsy specimens from 105 elderly patients (53 male subjects; mean age, 86.2 years) including 44 patients with CKD as a result of nephrosclerosis. The analysis was divided into two groups depending on whether they had CKD. RESULTS: The incidences of arterial intimal thickening (AIT), obsolescent-type global glomerulosclerosis (OB), and interstitial fibrosis and tubular atrophy (IF/TA) were higher in the CKD group than in the non-CKD group (all p < 0.01). These factors were all correlated with each other (AIT vs. OB, r = 0.43; AIT vs. IF/TA, r = 0.25; OB vs. IF/TA, r = 0.53). IF/TA had the strongest association with hypertension and decreased eGFR. In the non-CKD group, the frequency of OB was more than 20% in subjects aged 90 years or older. However, the individuals in the non-CKD group tended to have compensatory glomerular hypertrophy with increasing age and a retained eGFR, while the CKD group was unable to obtain compensatory hypertrophy and had a lower eGFR. We also found that AIT, OB and IF/TA occurred independently of systemic atherosclerosis. CONCLUSIONS: Non-CKD in the elderly refers to the so-called aging kidney. The progression from aging kidney to CKD caused by nephrosclerosis was influenced by increases in AIT, OB and IF/TA. IF/TA was thought to be the most important downstream factor in the progression of aging kidney to CKD.