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Abstract: PO2179

Acid-Base Biomarkers and Cancer Mortality

Session Information

  • Onco-Nephrology - 1
    October 22, 2020 | Location: On-Demand
    Abstract Time: 10:00 AM - 12:00 PM

Category: Onco-Nephrology

  • 1500 Onco-Nephrology


  • Verma, Ashish, Brigham and Women's Hospital, Boston, Massachusetts, United States
  • Subudhi, Sonu, Massachusetts General Hospital, Boston, Massachusetts, United States
  • Patel, Ankit B., Brigham and Women's Hospital, Boston, Massachusetts, United States
  • Tio, Maria Clarissa, Brigham and Women's Hospital, Boston, Massachusetts, United States
  • Waikar, Sushrut S., Boston University Medical Campus, Boston, Massachusetts, United States

Acidosis in the tumor microenvironment is associated with cancer progression in animal models. We explored the association of serum bicarbonate and anion gap – measures of acid-base balance -- with cancer mortality in community-dwelling adults.


We conducted a prospective cohort study using the National Health and Nutrition Examination Survey (NHANES), a nationally representative cross-sectional survey of the US non-institutionalized population. Anion gap (mEq/L) was calculated as serum sodium (mmol/L) – (serum chloride (mmol/L) + serum bicarbonate (mmol/L). We used weighted Cox proportional hazards models to assess the associations between serum bicarbonate and anion gap with cancer-specific mortality, as recorded by the National Death Index. Multivariable models were adjusted for demographics data, BMI, smoking status, diabetes, systolic blood pressure, cardiovascular disease history, ACEi/ARB, diuretics, HIV drugs, metformin, serum albumin, total cholesterol, total protein, total calorie intake, hemoglobin, cancer diagnosis, eGFR and urine albumin to creatinine ratio.


This study included total 39,137 participants [mean (SD) age, 46.83(19.25) years, 20,162(51.5%) females, 18,119 (46.3%) white]. During 4,433,277 person-years of follow up, 964 (2.46%) participants died secondary to cancer. A history of cancer at the time of enrollment was reported in 3186 (8.8%). Table 1 shows the associations between serum bicarbonate and anion gap in tertiles with cancer-related mortality. In analyses restricted to those with a history of cancer, results were 78% increased risk for cancer mortality in highest tertile compared to lowest tertile [ HR 1.78; 95% CI (1.11,2.87)].


Increased anion gap may be a risk factor for cancer mortality. The reasons driving this association deserve further examination.

Risk of cancer mortality according to bicarbonate and anion gap as tertiles (method = weighted survey cox regression)
 Unadjusted hazard ratioAdjusted hazard ratio
Bicarbonate T1
(10-22 mmol/l)
0.92 (0.75,1.12)1.21 (0.94,1.57)
Bicarbonate T2
(22-26 mmol/l)
Bicarbonate T3
(26-43 mmol/l)
1.42 (1.18,1.7)1.04 (0.82,1.32)
Anion gap T1
(< 10 mmol/l)
Anion gap T2
(10-12 mmol/l)
1.12 (0.91,1.36)1.21(0.94,1.57)
Anion gap T3
(> 12 mmol/l)
1.24 (0.99,1.56)1.59 (1.21,2.07)