Potassium Measures and Their Associations with Glucose and Diabetes Risk: The Multi-Ethnic Study of Atherosclerosis (MESA).
BACKGROUND
Recent studies have found low-normal potassium (K) to be associated with increased diabetes risk. We sought to verify these associations in a multi-ethnic US cohort; and to determine if these associations extend to US Hispanics and Asian-Americans.


METHODS
We analyzed data from Multi-Ethnic Study of Atherosclerosis (MESA) participants who were free-of-diabetes at baseline. We examined cross-sectional associations between measures of K-serum, dietary, and urine-with fasting glucose and HOMA-IR. We examined longitudinal associations between K and diabetes risk over 8 years.


RESULTS
In multivariable models, compared to those with higher serum K (≥4.5mmol/L), those with lower serum K (<4.0mmol/L) had significantly higher fasting glucose [1.3 mg/dL (95%CI 0.2, 2.4), P-value = 0.03]. Incident diabetes developed in 1281 of 5415 at-risk participants. In minimally-adjusted models, we found inverse associations between serum and dietary K and diabetes risk. Compared to those with higher serum K, those with lower serum K had an HR (95% CI) of incident diabetes of 1.23 (1.04, 1.47), P-value = 0.02. However, these associations were attenuated in fully-adjusted models. We found no significant interaction between potassium and ethnicity.


CONCLUSIONS
In this multi-ethnic cohort, we found a significant inverse association between serum K and fasting glucose but no significant association with longer-term diabetes risk. This inverse association between potassium and glucose must be studied further to understand the physiology and its potential impact on chronic health.
Department of Medicine, Duke University, Durham, NC, United States of America.
Ranee
R
Chatterjee
Department of Biostatistics, University of Washington, Seattle, WA, United States of America.
Leila
L
Zelnick
Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States of America.
Kenneth J
KJ
Mukamal
Division of Epidemiology, The University of Texas Health Sciences Center, Houston, TX, United States of America.
Jennifer A
JA
Nettleton
Department of Medicine, University of Washington, Seattle, WA, United States of America.
Bryan R
BR
Kestenbaum
The New York Academy of Medicine, New York, NY, United States of America.
David S
DS
Siscovick
Department of Medicine, University of California San Diego and Veterans Affairs San Diego Healthcare System, San Diego, CA, United States of America.
Joachim H
JH
Ix
Department of Pathology, University of Vermont, Burlington, VT, United States of America.
Russell
R
Tracy
Department of Lab Medicine, University of Washington, Seattle, WA, United States of America.
Andrew N
AN
Hoofnagle
Department of Medicine, Duke University, Durham, NC, United States of America.
Laura P
LP
Svetkey
Department of Medicine, Duke University, Durham, NC, United States of America.
David
D
Edelman
Department of Medicine, University of Washington, Seattle, WA, United States of America.|Department of Epidemiology, University of Washington, Seattle, WA, United States of America.
Ian H
IH
de Boer
D000368:Aged; D000369:Aged, 80 and over; D050197:Atherosclerosis / Q000097:blood / Q000150:complications / Q000208:ethnology / Q000652:urine; D001786:Blood Glucose / Q000378:metabolism*; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000097:blood / Q000208:ethnology / Q000209:etiology / Q000652:urine; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000097:blood / Q000652:urine; D012307:Risk Factors; D014481:United States / Q000453:epidemiology / Q000208:ethnology; D014812:Vitamin K / Q000097:blood
D001786:Blood Glucose; D014812:Vitamin K; D011188:Potassium