Relationship between vitamin D, parathyroid hormone, and bone mineral density in elderly Koreans.
There is controversy regarding definition of vitamin D inadequacy. We analyzed threshold 25-hydroxyvitamin D (25[OH]D) below which intact parathyroid hormone (iPTH) increases, and examined age- and sex-specific changes of 25(OH)D and iPTH, and association of 25(OH)D and iPTH with bone mineral density (BMD) in elderly Koreans. Anthropometric parameters, serum 25(OH)D and iPTH, lumbar spine and femur BMD by dual-energy radiography absorptiometry (DXA) were measured in 441 men and 598 postmenopausal women. iPTH increased below serum 25(OH) of 36.7 ng/mL in men, but failed to reach plateau in women. Femur neck BMD above and below threshold differed when threshold 25(OH)D concentrations were set at 15-27.5 ng/mL in men, and 12.5-20 ng/mL in postmenopausal women. Vitamin D-inadequate individuals older than 75 yr had higher iPTH than those aged ≤ 65 yr. In winter, age-associated iPTH increase in women was steeper than in summer. In conclusion, vitamin D inadequacy threshold cannot be estimated based on iPTH alone, and but other factors concerning bone health should also be considered. Older people seemingly need higher 25(OH)D levels to offset age-associated hyperparathyroidism. Elderly vitamin D-inadequate women in the winter are most vulnerable to age-associated hyperparathyroidism.
Department of Internal Medicine, Division of Endocrinology and Metabolism, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea.
Guilsun
G
Kim
Ki Won
KW
Oh
Eun-Hee
EH
Jang
Mee-Kyoung
MK
Kim
Dong-Jun
DJ
Lim
Hyuk Sang
HS
Kwon
Ki-Hyun
KH
Baek
Kun-Ho
KH
Yoon
Won Chul
WC
Lee
Bong Yun
BY
Cha
Kwang-Woo
KW
Lee
Ho-Young
HY
Son
Moo-Il
MI
Kang
D015502:Absorptiometry, Photon; D000367:Age Factors; D000368:Aged; D015519:Bone Density; D005260:Female; D005269:Femur / Q000033:anatomy & histology; D006801:Humans; D006961:Hyperparathyroidism / Q000175:diagnosis / Q000209:etiology; D008161:Lumbosacral Region / Q000033:anatomy & histology; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D017698:Postmenopause; D056910:Republic of Korea; D012621:Seasons; D012737:Sex Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
D010281:Parathyroid Hormone; D014807:Vitamin D; C104450:25-hydroxyvitamin D