Adults with higher aldosterone levels are more likely to develop type 2 diabetes over 10 years vs. those with lower levels, with the risk further increasing for Asian, black and Hispanic adults, according to findings published in the Journal of the American Heart Association.
Joshua J. Joseph
“When you look at the participants’ aldosterone levels, our study found the group in the top third of aldosterone had more than twice the risk of getting diabetes than the people who had levels in the lowest third,” Joshua J. Joseph, MD, assistant professor of medicine in the division of endocrinology, diabetes and metabolism at The Ohio State University Wexner Medical Center, told Endocrine Today. “We also found that African-Americans and Chinese-Americans with high aldosterone levels had an even greater risk. The hormone aldosterone is one potential link between the development of hypertension and diabetes.”
Joseph and colleagues analyzed data from 1,570 adults aged 45 to 80 years without evidence of diabetes or cardiovascular disease at baseline, participating in the Multiethnic Study of Atherosclerosis (MESA; mean age, 64 years; 51% women). Within the cohort, 24% were Hispanic, 20% were black and 13% were Chinese-American. At 3 and 4.5 years after baseline, participants underwent measurements of plasma renin activity and aldosterone levels as part of an ancillary study, and provided fasting blood samples to measure serum glucose, insulin and serum creatinine. Researchers measured insulin resistance and beta-cell function via the updated computer-based homeostatic model assessment of insulin resistance.
Researchers used linear regression analysis to examine the cross-sectional associations of aldosterone with fasting plasma glucose, insulin resistance and beta-cell function, and Cox regression analysis to estimate HRs for incident type 2 diabetes.
During a median follow-up of 10.5 years, 116 adults developed type 2 diabetes, for an incidence rate of 7.9 per 1,000 person-years. Incidence rates for type 2 diabetes were higher among adults in the second and third tertile of aldosterone level (10.7 and 9.3 per 1,000 person-years, respectively) vs. those in the first tertile (3.6 per 1,000 person-years), according to researchers.
After adjustment for multiple factors, including waist circumference and use of angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers, a 1-standard-deviation increase in log-transformed aldosterone level was associated with a 44% increased risk for type 2 diabetes (HR = 1.44; 95% CI, 1.16-1.78). Diabetes risk increased markedly for those in the second and third tertiles of aldosterone level vs. adults in the first tertile, with HRs of 3.37 (95% CI, 1.96-5.8) and 3.25 (95% CI, 1.86-5.69), respectively; however, adjustment for inflammatory markers and adipokines attenuated the associations.
In race-stratified analyses, researchers observed an increased risk for Chinese, black and Hispanic adults vs. white adults. After adjustment for waist circumference and the use of ACE inhibitors or angiotensin receptor blockers, a 1-standard-deviation increase in log-transformed aldosterone level was associated with an HR of 2.42 for Chinese participants (95% CI, 1.31-4.46); an HR of 1.49 for black participants (95% CI, 0.94-2.36); an HR of 1.42 for Hispanic adults (95% CI, 0.99-2.03) and an HR of 1.01 for white adults (95% CI, 0.66-1.55). Researchers further observed dose-dependent, linear associations among Chinese-Americans (P = .011) and black participants (P = .008), and nonlinear associations among Hispanic and white participants.
After adjustments for multiple factors, including waist circumference, adults in the third tertile of plasma renin activity had a 27% increased risk for type 2 diabetes vs. those in the first tertile; however, this association no longer reached significance after further adjustment for the use of ACE inhibitors and angiotensin receptor blockers, according to researchers.
The researchers noted that type 2 diabetes risk was higher per log-transformed aldosterone standard deviation among participants with both unsuppressed renin phenotype and suppressed renin phenotype, indicating that adults with physiologically and autonomously higher aldosterone are both at higher risk for the disease.
“We are currently working on research to determine clinical cutoffs that might be beneficial for risk prediction combined with current type 2 diabetes risk prediction tools,” Joseph said.
Joseph said the researchers next plan to evaluate the role of aldosterone in glucose metabolism in black adults with prediabetes in a study funded by the NIH.
“Our team will study the impact on blood glucose and insulin in those individuals,” Joseph said. “This research has the potential to guide clinical care in the future.” – by Regina Schaffer
For more information:
Joshua J. Joseph, MD, can be reached at the Division of Endocrinology, Diabetes and Metabolism, The Ohio State University Wexner Medical Center, 566 McCampbell Hall, 1581 Dodd Drive, Columbus, OH 43210; email: firstname.lastname@example.org.
Disclosures: The authors report no relevant financial disclosures.