Younger-Onset Type 2 Diabetes: Features and Implications

A recent study found that among younger individuals, type 2 diabetes often occurs in the setting of higher rates of adiposity and a slightly more rapid rise in hemoglobin A1C (HbA1c) levels, but better systolic blood pressure (SBP) values and estimated glomerular filtration rates (eGFR).1

The Bottom Line

Data from the study showed that younger age at type 2 diabetes onset was associated with higher BMI and a slightly more rapid rise in HbA1c levels, but better systolic blood pressure values and estimated glomerular filtration rates.The inclusion of 2 distinct cohorts from different settings, with Western (US-DPP) and South Asian (K-DPP) populations represented, strengthens the findings.Differences in biomarkers trajectories by age of onset could have implications for long-term risk.

Currently, evidence suggests that younger age at onset of type 2 diabetes might be linked to worse long-term outcomes compared with disease onset in middle-aged and older adult patients.2,3

For this study, researchers sought to establish whether age at onset of type 2 diabetes impacts disease progression based on changes in glycemic control and clinical biomarkers observed during follow-up. Data obtained from 2 diabets prevention trials—the U.S. Diabetes Prevention Program (US-DPP) and the Kerala Diabetes Prevention Program (K-DPP)—were used in the analysis.1

The study employed 3 complementary strategies to assess the link between age at type 2 diabetes onset and clinical biomarkers1:

Cross-sectional associations at onset of diabetes
Cross-sectional associations at end of follow-up (mean follow-up, approximately 8 years; prospective)
Longitudinal trajectories of changes during follow-up

Data were collected at the onset of disease and at the end of follow-up and included key indicators of metabolic and cardiovascular health1:

Blood sugar: fasting plasma glucose (FPG)
Levels of fats: triglycerides (TGs), high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol
Blood pressure
Weight: body mass index (BMI) 
Kidney function: eGFR

Study participants included 802 individuals with newly diagnosed type 2 diabetes from the US-DPP and 146 patients from the K-DPP.1

The US-DPP was a randomized controlled trial that was conducted at 27 different centers located across the United States. All participants, aged 25 years and older, had FPG levels of 5.3 to 6.9 mmol/L and/or 2-hour plasma glucose (2hPG) levels of 7.8 to 11.0 mmol/L, along with a BMI of ≥24 kg/m2.1

The K-DPP was a cluster-randomized controlled trial conducted in Kerala, India, between 2013 and 2016. Participants, who were aged 30 to 60 years, were chosen randomly from 60 electoral districts. Individuals with an Indian Diabetes Risk Score of ≥60 who did not fulfill the diabetes criteria of the American Diabetes Association were included in the study.1

The mean age of the K-DPP cohort was significantly lower than that of the US-DPP cohort (47.7 ± 7.0 years vs 52.6 ± 10.2 years, respectively; P<.001).1

In the current study, the definition of diabetes was derived from the American Diabetes Association. This includes FPG levels of ≥7.0 mmol/L and/or 2hPG levels of ≥11.1 mmol/L. All participants in this study were considered to have type 2 diabetes.1

Results of the study revealed that at onset of diabetes, younger age was statistically significantly associated with a higher BMI (P=.003 in the K-DPP arm vs P<.001 in the US-DPP arm), as well as lower SBP (P=.02 in the K-DPP group vs P<.001 in the US-DPP group) and lower HDL cholesterol levels (P=.049 in the K-DPP cohort vs P<.001 in the US-DPPP cohort). Further, in the US-DPP arm, but not in the K-DPP arm, younger age at diabetes onset was associated with significantly higher diastolic blood pressure (DBP), FPG levels, and eGFR (P<.001, P=.002, and P<.001, respectively).1

Patients in the K-DPP cohort were diagnosed with a statistically significantly lower mean BMI than those in the US-DPP cohort (26.6 ± 4.1 kg/m2 vs 35.8 ± 8.0 kg/m2, respectively).1

Additionally, at diabetes onset, those in the K-DPP arm had higher FPG levels than those in the US-DPP arm (7.5 ± 1.5 mmol/L vs 7.0 ± 1.2 mmol/L, respectively). The K-DPP participants compared with the US-DPP participants, however, had lower HbA1c levels (6.1% ± 0.8% vs 6.4% ± 0.8%, respectively) and lower 2hPG levels (9.9 mmol/L [range, 7.3-11.8 mmol/L] vs 11.9 mmol/L range, 10.9-13.0 mmol/L], respectively).1

Participants were observed for an average of 7.6 years in the K-DPP cohort compared with 7.9 years in the US-DPP cohort. At the end of follow-up, younger age at onset of diabetes was statistically significantly associated with these factors1:

Higher BMI: K-DPP, P=.01; US-DPP, P<.001 Higher FPG: K-DPP, P=.04; US-DPP, P<.001 Higher LDL: P<.001 in both cohorts Higher eGFR: P<.001 in both cohorts Lower HDL: K-DPP, P=.03; US-DPP, P<.001 Lower SBP: K-DPP, P=.009; US-DPP, P<.001

Although younger patients exhibited higher HbA1c and TG levels, as well as higher DBP values, these associations were significant in the US-DPP cohort only.1

Several limitations of the current analysis warrant mention. Because both the US-DPP and the K-DPP were randomized controlled trials, this might impact generalizability. In fact, since the majority of the follow-up period occurred after completion of the trial interventions, the initial exposure might still have a residual impact on participant behavior, clinical management, or metabolic outcomes.1

Further, individuals in both trials were volunteers who fulfilled specific eligibility criteria. In fact, these patients “may represent more health-conscious or homogenous subsets of the populations.”1

According to the researchers, “Long duration of diabetes is one of the strongest determinants of the risk of complications among people with diabetes, and our study is one of the few that minimizes the effect of duration by including individuals at diabetes onset rather than using statistical adjustments for the duration.”1

Also, “this study overcomes another important limitation . . . by having an accurate age at diabetes onset, because all participants were free of diabetes when entering the trial, and follow-up for the current analysis began only when diabetes was subsequently detected.”1

The inclusion of 2 distinct cohorts from different settings, with Western (US-DPP) and South Asian (K-DPP) populations represented, strengthens the findings. Notably, participants from the US-DPP and K-DPP cohorts have varying risk profiles and health care contexts.1

“The broadly consistent findings suggest that the relationship between age at diabetes onset and biomarker trajectories may be generalizable across diverse populations,” the authors highlighted.

Published: February 05, 2026