Introduction:
Studies have shown poorer cognitive function in children and adolescents with type 1 diabetes (T1D) as compared to non-diabetic peers. However, little is known about cognitive function in older adults with T1D.
Hypothesis:
We hypothesized that older adults with T1D and type 2 diabetes (T2D) would have greater cognitive impairment than age, sex, race/ethnicity, and education-matched controls without diabetes.
Methods:
We compared baseline cognitive impairment among older adults (aged ≥60) from the Study of Longevity in Diabetes (SOLID) with T1D (n=771), T2D (=234) and no diabetes (n=253). Cognitive tests assessed three cognitive domains identified via factor analysis (language, executive function, episodic memory). All cognitive test scores were standardized and cognitive impairment was defined as 1.5 SD below the mean. In logistic regression models adjusted for age, sex, education, and race/ethnicity, we examined the association between diabetes status (T1D, T2D or no diabetes) and cognition on each cognitive domain and on global cognition (average of scores on the 3 domains).
Results:
In adjusted regression models, compared to older adults without diabetes, those with T1D were more likely to have impaired cognitive function on the language (OR=2.13, 95% CI: 1.08, 4.17) and executive function domains (OR=2.66, 95% CI: 1.36, 5.22). No significant differences in global cognitive impairment or impairment on the episodic memory domain were observed for T1D and no significant differences on any domain were observed for T2D.
Conclusions:
Our findings suggest that older adults with T1D have greater cognitive impairment than their peers without diabetes; findings were specific to the language and executive function domains, with episodic memory being unaffected. No increase in cognitive impairment was observed for older adults with T2D. Additional research is needed to understand the causes and potentially modifiable factors associated with impaired cognition among older adults with T1D.