Effects of Age and Body Mass Index on Thoracolumbar Spine X-Ray for Diagnosing Osteoporosis in Elderly Women: Tianliao Old People (TOP) Study 07.
OBJECTIVE
The aim of this study was to determine the effects of diagnostic discordance with or without a thoracolumbar spine lateral view X-ray in patients with osteoporosis.


METHODS
We randomly enrolled 368 women over 65 years old (74.3 ± 6.0 years) from Tianliao Township in 2009 (response rate: 75.7%). A diagnosis of osteoporosis was confirmed using one of these criteria: (1) a history of non-traumatic fracture, (2) vertebral fractures based on a thoracolumbar spine lateral view X-ray, or (3) a bone mineral density T-score ≤ -2.5 for the total hip, the femoral neck, the lumbar spine, or all 3 sites. The prevalence of osteoporosis in three groups was compared based on Model I (criteria 1+2) vs. Model II (criteria 1+3) vs. Model III (criteria 1+2+3). The role of thoracolumbar X-ray reflected by the diagnostic discordance of osteoporosis between Models II and III was evaluated.


RESULTS
The overall prevalence of osteoporosis was 78.3% (Model III, age-standardized 78.1%). The diagnostic discordance was 17.4% in the 368 participants. A logistic regression model showed that age was negatively associated with diagnostic discordance (odds ratio [OR] = 0.93, 95% confidence interval [CI]: 0.88-0.98, p < 0.05), but body mass index was positively associated (OR = 1.07, 95% CI: 1.00-1.15, p < 0.05).


CONCLUSIONS
A thoracolumbar spine lateral view X-ray should be added for women ≥ 65 years old or with a body mass index ≥ 25 kg/m2 to minimize the diagnostic discordance in osteoporosis, especially in highly endemic regions.
Department of Family Medicine, National Cheng Kung University Hospital, Tainan, Taiwan.
Yin-Fan
YF
Chang
Department of Family Medicine, National Cheng Kung University Hospital, Tainan, Taiwan.
Chin-Sung
CS
Chang
Department of Radiology, Tainan Hospital Xinhua Branch, Department of Health, Tainan, Taiwan.
Mei-Wen
MW
Wang
Department of Family Medicine, Kuo General Hospital, Tainan, Taiwan.
Chun-Feng
CF
Wu
Dynasty clinic, Tainan, Taiwan.
Chuan-Yu
CY
Chen
Department of Family Medicine, Changhua Christian Hospital, Changhua, Taiwan.
Hsuan-Jui
HJ
Chang
Department of Public Health & Institute of Epidemiology, College of Public Health, National Taiwan University, Taipei, Taiwan.
Po-Hsiu
PH
Kuo
Department of Family Medicine, National Cheng Kung University Hospital, Tainan, Taiwan.
Chih-Hsing
CH
Wu
D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D003710:Demography; D005260:Female; D006801:Humans; D016015:Logistic Models; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging*; D010024:Osteoporosis / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000453:epidemiology; D015995:Prevalence; D012307:Risk Factors; D012424:Rural Population; D013624:Taiwan / Q000453:epidemiology; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging*; D014965:X-Rays