Compared to participants with high lung function, those with low lung function were more likely to be older, non-white, not college educated, have higher TDI and BMI, have poorer brain health (smaller volumes and poorer white matter health), be a former or current smoker, be non-drinking, have irregular physical activity, have high level of social connection, be an APOE ε4 non-carrier, and have hypertension, diabetes, or heart disease (Table 1). Here, APOE is linked to diabetes mellitus.