Key points Is age at diabetes diagnosis associated with risk of distal outcomes among adults aged 50 years and older? Findings This cohort study of 36,060 adults aged 50 years and older used data from a national longitudinal health survey and found that diabetes diagnosed between ages 50 and 59 was significantly associated with elevated risks of incident heart disease, stroke, disability, cognitive impairment, and mortality. However, associations between diabetes and all outcomes decreased as age at diabetes diagnosis increased, even controlling for duration of diabetes. Meaning Differences in the association of diabetes with negative health outcomes support differential management of diabetes between age groups at diagnosis. |
Importance
Older adults vary widely in age at diagnosis and duration of type 2 diabetes, but treatment often ignores this heterogeneity.
Goals
To investigate the associations of diabetes versus non-diabetes, age at diagnosis, and duration of diabetes with negative health outcomes in people aged 50 years and older.
Design, environment and participants
This cohort study included participants in the 1995 to 2018 waves of the Health and Retirement Study (HRS), a biennial, population-based longitudinal health interview survey of older adults in the U.S. The study sample included adults 50 years or older (n = 36,060) without diabetes at admission. Data was analyzed from June 1, 2021 to July 31, 2022.
Exhibitions
The presence of diabetes, specifically age at diabetes diagnosis, was the primary exposure of the study. Age at diagnosis was defined as the age at which the respondent first reported diabetes. Adults who developed diabetes were classified into 3 age groups at diagnosis: 50 to 59 years, 60 to 69 years, and 70 years or older.
Main results and measures
For each diabetes group with age at diagnosis, a propensity score-matched control group of respondents who never developed diabetes was constructed.
We estimated the association of diabetes with the incidence of key outcomes, including heart disease, stroke, disability, cognitive impairment, and all-cause mortality, and estimated the association of diabetes versus nondiabetes between case age at time of diagnosis and the matched control groups with which it was compared.
Results
A total of 7739 HRS respondents developed diabetes and were included in the analysis (4267 women [55.1%]; mean [SD] age at diagnosis, 67.4 [9.9] years).
Age groups at diagnosis included 1,866 respondents aged 50 to 59 years, 2,834 respondents aged 60 to 69 years, and 3,039 respondents aged 70 years or older; 28,321 HRS respondents never developed diabetes.
Age at diagnosis of 50 to 59 years was significantly associated with incident heart disease (hazard ratio [HR], 1.66 [95% CI, 1.40-1.96]), stroke (HR, 1 .64 [95% CI, 1.30-2.07]), disability (HR, 2.08 [95% CI, 1.59-2.72]), cognitive impairment (HR, 1.30 [95% CI, 1.30-2.07]), %, 1.05-1.61]) and mortality (HR, 1.49 [95% CI, 1.29-1.71]) compared with matched controls, even taking into account duration of diabetes.
These associations decreased significantly with advancing age at diagnosis.
Figure : Cumulative incidence curves of distal outcomes for each age group at diagnosis with diabetes and its matched control (MC) group
Conclusions and relevance
Findings from this cohort study suggest that age at diabetes diagnosis was differentially associated with outcomes and that younger age groups were at elevated risk for heart disease, stroke, disability, cognitive impairment, and mortality from diabetes. all causes.
These findings reinforce the clinical heterogeneity of diabetes and highlight the importance of improving diabetes control in adults with early diagnosis.
Final message
This cohort study provides evidence for the differential association of diabetes with incident distal outcomes across different ages at diabetes diagnosis while accounting for duration of diabetes.
With increasing age at diagnosis, diabetes is associated with significantly lower risks of incident comorbid outcomes. In adults who were younger at diabetes diagnosis (50-59 years), diabetes was significantly associated with increased HR for each distal outcome.
In contrast, the association was not significant for the older diagnosis group (≥70 years).
We believe this study provides a framework for future studies that can explore other key variables associated with diabetes-related health outcomes. Metabolic mechanisms, lifestyle and behaviors, social determinants of health, and diabetes control affect age at diabetes diagnosis and aging with diabetes. Future studies should address the full complexity of diabetes and its effects over time.
