A number of studies have demonstrated that people with high blood pressure are at increased risk of developing chronic kidney disease (CKD) and end-stage renal disease (ESRD).1–6 In some studies, the higher the blood pressure, the greater the risk.2–4 Experts hypothesize that elevated systemic blood pressure can be transmitted to and damage the glomerulus, the basic filtration unit of the kidney, contributing to progressive kidney disease.7
Iseki et al. used data from community mass screening programs of dipstick urinalysis and blood pressure readings (n=107,192) in Japan to evaluate risk factors for the development of ESRD.4 After 10 years of follow-up, 193 patients in this cohort were identified in dialysis center databases with ESRD. Diastolic blood pressure at initial screening was a significant risk factor for ESRD (odds ratio [OR] 1.39, 95% confidence interval [CI] 1.17 – 1.64). Having a positive urine dipstick (proteinuria or hematuria) or male gender was also a strong predictor of ESRD.
Fox et al. conducted a longitudinal study of 2,585 participants without kidney disease who were examined at baseline and again an average of 18.5 years later.1 At the second examination, 244 people (9.4%) had developed kidney disease, defined as having a glomerular filtration rate (GFR) at or below the fifth percentile. Using stepwise logistic regression analysis, the authors determined significant risk factors for the development of kidney disease. The presence of hypertension (systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg or taking antihypertension medication) at baseline predicted the development of kidney disease (OR 1.57, 95% CI [1.17—2.12]).
Haroun et al. conducted a prospective observational study in 23,534 men and women over 20 years to examine risk factors for the development of CKD, defined as ESRD listed in the Health Care Financing Administration database or kidney disease listed on the death certificate.2 Women with stage 1 hypertension (140 – 159 mm Hg systolic or 90 – 99 mm Hg diastolic) at baseline and stage 2 hypertension (160 – 179 mm Hg systolic or 100 – 109 mm Hg diastolic) at baseline were significantly more likely to develop CKD (OR 6.3, 95% CI [1.3 – 29] and OR 8.8, 95% CI [1.8 – 43.0], respectively). In men, the risk was significant when baseline blood pressure indicated stage 2 hypertension (OR 9.7, 95% CI [1.2 – 75.6]).
Klag et al. assessed the risk of developing ESRD in 332,544 patients who had been screened for eligibility in the Multiple Risk Factor Intervention Trial.5 ESRD was determined from databases and records from the Health Care Financing Administration, death records, the National Death Index, and the Social Security Administration. Compared to men with optimal blood pressure at baseline (under 120 mm Hg systolic and under 80 mm Hg diastolic), the relative risk of ESRD for men with stage 4 hypertension (systolic pressure 210 mm Hg or higher or diastolic pressure 120 mm Hg or higher) was 22.1 (p<0.001).
Even though the development of ESRD is significantly associated with the presence of high blood pressure at baseline, it does not prove that high blood pressure, itself, causes kidney damage.3,7,8 Renal disease can lead to hypertension, so it can be argued that these associations may be due to underlying primary kidney disease at baseline. Hsu et al. conducted a historical study among participants in Kaiser Permanente of Northern California, a large integrated health care delivery system, to screen out underlying baseline kidney disease when assessing risk factors for development of ESRD.3 Adult Kaiser members (n=316,675) who participated in the Multiphasic Health Checkups between 1964 and 1985 and had normal GFR and negative dipstick urinalyses at baseline were followed. Among the participants, 1,149 developed ESRD. Even moderate elevations in blood pressure at baseline (120 – 129/80 – 84 mm Hg) were associated with increased risk for ESRD (relative risk [RR] 1.62, 95% CI [1.27 – 2.07]) compared to participants with optimal blood pressure. Relative risks increased as the baseline blood pressure levels increased. Compared to optimal blood pressure at baseline, the RR for ESRD for blood pressure of 210/120 mm Hg or higher was 4.25 (95% CI [2.63 – 6.86]).The data suggests that blood pressure is an independent risk factor for the development of ESRD.
The relative risk of developing serious kidney disease in patients with high blood pressure is low when compared to the risk of developing other cardiovascular complications.8,9 However, because hypertension is prevalent in the general population, it is the second leading causes of ESRD after diabetes.9
References
- Fox CS, Larson MG, Leip EP, Culleton B, Wilson PWF, Levy D. Predictors of new-onset kidney disease in a community-based population. JAMA 2004; 291 (7): 844-850.
- Haroun MK, Jaar BG, Hoffman SC, Comstock GW, Klag MJ, Coresh J. Risk factors for chronic kidney disease: a prospective study of 23,534 men and women in Washington County, Maryland. J Am Soc Nephrol 2003; 14 (11): 2934-2941.
- Hsu CY, McCulloch CE, Darbinian J, Go AS, Iribarren C. Elevated blood pressure and risk of end-stage renal disease in subjects without baseline kidney disease. Arch Intern Med 2005; 165 (8): 923-928.
- Iseki K, Iseki C, Ikemiya Y, Fukiyama K. Risk of developing end-stage renal disease in a cohort of mass screening. Kidney Int 1996; 49 (3): 800-805.
- Klag MJ, Whelton PK, Randall BL, et al. Blood pressure and end-stage renal disease in men. N Engl J Med 1996; 334 (1): 13-18.
- Tozawa M, Iseki K, Iseki C, Kinjo K, Ikemiya Y, Takishita S. Blood pressure predicts risk of developing end-stage renal disease in men and women. Hypertension 2003; 41 (6): 1341-1345.
- Taal M. Risk Factors and Chronic Kidney Disease. In: Brenner and Rector’s The Kidney. Elsevier Inc; 2016:669-692.
- Mennuni S, Rubattu S, Pierelli G, Tocci G, Fofi C, Volpe M. Hypertension and kidneys: unraveling complex molecular mechanisms underlying hypertensive renal damage. J Hum Hypertens 2014; 28 (2): 74-79.
- US Renal Data System. https://www.usrds.org. Accessed Oct 26, 2018.
