After adjustment of age and BMI, both hands grip strength, height loss over 3 cm, serum levels of β-CTx, PINP, and OST were the independent risk factors for osteoporosis in both men and women; besides, familial Alzheimer’s disease history in men; and history of steatohepatitis and fracture, serum levels of PTH and ALT, age of menarche, age of menopause, duration of menstruation in women, were also risk factors of osteoporosis. Here, PTH is linked to early-onset autosomal dominant Alzheimer disease.