APOE and obesity due to melanocortin 4 receptor deficiency: However, to date, the combined association of walking pace and grip strength with the risk of dementia, as well as the modifying effects of age, APOE phenotypes, and other important dementia risk factors, including obesity, physical activity, hypertension, depression, and diabetes, on the relationship between walking pace and new-onset dementia, have not been comprehensively investigated.