Cardiovascular complications
The cardiovascular event rate in TODAY 2 was about the same as is seen in older adults with type 1 diabetes. Overall, there were 38 cardiovascular events in 19 patients for an event rate of 6.4/1,000 patients per year. Those events included heart failure, arrhythmia, coronary artery disease or myocardial infarction, deep venous thrombosis, stroke or transient ischemic attack, and vascular insufficiency.
Over that time, the cumulative incidence of elevated LDL cholesterol increased from 3% in the TODAY report to 26% for TODAY2, and for triglycerides, it went from 18% to 35%. The cumulative incidence of hypertension increased from 19% to 55%.
Decline renal function
In regard to renal complications, the cumulative incident curve for microalbuminuria went from 8% at baseline to 40% at 12 years, while macroalbuminuria prevalence increased from 1.5% to 11% during the same time. The cumulative incidence of hyperfiltration increased from 12% to 48%. Risk factors for hyperfiltration included female sex, Hispanic ethnicity, loss of glycemic control, and hypertension, although body mass index was actually associated with lower risk.
So far, there have been four renal events in two patients, who both had chronic kidney disease and end-stage renal failure, for an event rate of 0.7/1,000 patients per year.
Pregnancy outcomes
Women in the cohort – about two-thirds of the study population – have had high rates of maternal complications, and their offspring also face complications after birth.
There were 306 pregnancies reported, of which there are known outcomes for 53 (TODAY) and 236 (TODAY2). In all, 5% of the total cohort had voluntary elective termination; 9% and 12% of patients, respectively, suffered a miscarriage before 20 weeks; and 4% of pregnancies in the total cohort ended in stillbirth.
Preterm live births more than doubled from 11% to 24%, and full-term deliveries decreased from 62% to 46% in the TODAY2 patients.
In regard to offspring characteristics, average birth weight in the total cohort was just over 4.5 pounds (national average, 7.3 pounds), and the prevalence of very low birth weight more than doubled from 8% to 16% at the 12-year mark. The prevalence of macrosomia was 19% for the cohort, more than double the national average of 8%. In all, 5% and 7% of offspring were small for gestational age, whereas 22% and 26% of offspring were large for gestational age.
Among other complications, respiratory distress occurred in 8% and 14% of offspring, and cardiac anomalies occurred in 10% and 9%, which, although they held steady across the cohorts, were significantly higher than the national average of 1%. Similarly, neonatal hypoglycemia occurred in 17% and 29% of offspring, again, notably higher than the national average of 2%. Offspring outcomes were worse in mothers with loss of glycemic control.
In regard to maternal pregnancy complications, the rate of hospitalization before delivery increased from 25% to 36%; hypertension increased in prevalence from 19% to 36%; and while macroalbuminuria held steady at 9.4%, microalbuminuria increased from 6% to 8%. Thirty-three percent of the TODAY2 cohort had a hemoglobin A1c level of more than 8%.