The relationship between back pain and future vertebral fracture in postmenopausal women

Multidimensional characteristics of musculoskeletal pain and risk of hip fractures among elderly adults: the first longitudinal evidence from CHARLS

BACKGROUND

Hip fractures are a major public health concern among middle-aged and older adults. It is important to understand the associated risk factors to inform health policies and develop better prevention strategies. Musculoskeletal pain is a possible implicating factor, being associated with physical inactivity and risk of falls. However, the association between musculoskeletal pain and hip fractures has not been clearly investigated.

METHODS

A nationally representative sample of the Chinese population was obtained from the China Health and Retirement Longitudinal Study (CHARLS). The study collected patient information on their demographic characteristics, socioeconomic status, other health-related behavior, and history of musculoskeletal pain and hip fractures. Univariate and multivariate analyses were conducted to investigate the factors influencing the risk of hip fracture, including factors related to the individual and to musculoskeletal pain. P for trend test was performed to assess the trend of each continuous variable. The robustness and bias were assessed using the bootstrap method. Restricted cubic spline regression was utilized to identify linear or non-linear relationships.

RESULTS

Among the 18,813 respondents, a total of 215 individuals reported that they have experienced a hip fracture. An increased risk of hip fracture was associated with the presence of waist pain and leg pain (P < 0.05), as well as with an increased number of musculoskeletal pain sites (P < 0.05). For individuals aged 65 and above, a significant association was found between age and the risk of hip fracture (P < 0.05). Furthermore, respondents with lower education level had a higher risk of hip fracture compared to those with higher education levels (P < 0.05).

CONCLUSION

In the Chinese population, the risk of hip fracture was found to be associated with both the location and extent of musculoskeletal pain, as well as with other factors such as age and demographic characteristics. The findings of this study may be useful for informing policy development and treatment strategies, and provide evidence for comparison with data from other demographic populations.

Association of Pain Phenotypes with Risk of Falls and Incident Fractures

Objective: To compare whether falls risk score and incident fracture over 10.7 years were different among three previously identified pain phenotypes. Methods: Data on 915 participants (mean age 63 years) from a population-based cohort study were studied at baseline and follow-ups at 2.6, 5.1 and 10.7 years. Three pain phenotypes were previously identified using the latent class analysis: Class 1: high prevalence of emotional problems and low prevalence of structural damage; Class 2: high prevalence of structural damage and low prevalence of emotional problems; Class 3: low prevalence of emotional problems and low prevalence of structural damage. Fractures were self-reported and falls risk score was measured using the Physiological Profile Assessment. Generalized estimating equations model and linear mixed-effects model were used to compare differences in incident fractures and falls risk score over 10.7 years between pain phenotypes, respectively. Results: There were 3 new hip, 19 vertebral, and 121 non-vertebral fractures, and 138 any site fractures during 10.7-year follow-up. Compared with Class 3, Class 1 had a higher risk of vertebral (relative risk (RR) = 2.44, 95% CI: 1.22-4.91), non-vertebral fractures (RR = 1.20, 95% CI: 1.01-1.42), and any site fractures (RR = 1.24, 95% CI: 1.04-1.46) after controlling for covariates, bone mineral density and falls risk score. Class 2 had a higher risk of non-vertebral and any site fracture relative to those in Class 3 (non-vertebral: RR = 1.41, 95% CI: 1.17-1.71; any site: RR = 1.44, 95% CI: 1.20-1.73), but not vertebral fracture. Compared with Class 3, Class 1 had a higher falls risk score at baseline (β = 0.16, 95% CI: 0.09-0.23) and over 10.7-year (β = 0.03, 95% CI: 0.01-0.04). Conclusions: Class 1 and/or Class 2 had a higher risk of incident fractures and falls risk score than Class 3, highlighting that targeted preventive strategies for fractures and falls are needed in pain population.

Impact of three-dimensional chemoradiation on pelvic bone mineral density, low back pain, and disability in cervical cancer: a prospective study

OBJECTIVE

To prospectively analyze the effect of three-dimensional chemoradiation on the bone mineral density of pelvic bones and its association with low back pain and disability in patients with locally advanced cervical cancer.

METHODS

In biopsy proven locally advanced cervical cancer patients, bone mineral density and T scores for lumbar vertebrae 5, dorsal thoracic vertebrae 12, and T scores for the femoral neck were analyzed. Low back pain was scored using the visual analog scale while disability scoring was done using the Oswestry low back pain disability scale. Furthermore, a subgroup analysis for patients (classified according to menopausal status) was performed.

RESULTS

In total, 106 patients were analyzed. A statistically significant decline in mean bone mineral density was observed at all three sites (vertebrae 5 and 12, and the femoral neck) post-chemoradiation therapy compared with pretreatment bone mineral density (0.671 vs 0.828, -2.083 vs -1.531, -2.503 vs -1.626; all p<0.001). Similarly, in subgroup analyses, at all three sites, pre-menopausal patients showed a statistically significant association (0.876 vs 0.697, -1.203 vs -0.2.761, -1.403 vs -2.232; all p<0.001) while a non-significant association was observed for post-menopausal patients at vertebrae 12 (-1.707 vs -1.719; p=0.09) with a statistically significant association at vertebrae 5 and the femoral neck (0.803 vs 0.656, -1.746 vs -2.648; p<0.01). Although statistically significant low back pain and disability scores were observed overall and irrespective of menopausal status, no correlation between bone mineral density and low back pain and disability was observed.

CONCLUSION

Pelvic bone mineral density decreases significantly after chemoradiation, irrespective of menopausal status. However, no correlation with low back pain and disability was observed. Pelvic bone mineral density analysis should be considered before chemoradiation in cervical cancer.

Study on the relationship between low back pain and emotional state, sleep and quality of life in postmenopausal women

OBJECTIVE

The aim of this study was to investigate the incidence of low back pain in the postmenopausal period and the relationship between low back pain and emotional state, sleep and quality of life.

METHODS

This cross-sectional study was conducted with 368 postmenopausal women between 40 and 65 years old. The frequency and severity of low back pain were recorded for all participants, as well as depressive symptoms and anxiety, quality of life and sleep quality.

RESULTS

90.2% of the participants reported low back pain. As low back pain severity increased, it was found that depression, anxiety levels, NHP and PSQI total scores increased as well (p= 0.0001). Significant positive correlations were found between pain intensity and outcome measures, except for sleep duration and habitual sleep efficiency (p< 0.01).

CONCLUSION

A great majority of women experience postmenopausal low back pain, which causes significant problems that negatively affect their quality of life, emotional state and sleep quality.

Pain at Multiple Sites Is Associated With Prevalent and Incident Fractures in Older Adults

Musculoskeletal pain is common and typically occurs at multiple sites. Pain has been shown to be associated with falls risk; however, whether an increased risk for falls associated with multisite pain (MSP) translates into an increased risk of fractures has not been investigated. This study aimed to examine the association of number of painful sites with prevalent and incident fractures. Data from a longitudinal population-based study of older adults (mean age 63 years) were utilized. Follow-up was performed at 2.6, 5.1, and 10.7 years later, respectively. Presence/absence of pain at the neck, back, hands, shoulders, hips, knees, and feet was assessed by questionnaire at baseline. Participants were classified into three groups according to the total number of painful sites: zero to two, three to four, and five to seven. Fractures were self-reported at each time point. BMD was measured by DXA. Falls risk was calculated based on the Short-Form Physiological Profile Assessment. Log-binomial regression was used for the analyses. There were 450 fractures at baseline and 154 new fractures reported during a mean follow-up period of 10.7 years (range 9.2 to 12.5 years). In multivariable analyses, number of painful sites was associated with prevalent fractures at any and nonvertebral site. Furthermore, participants with five to seven painful sites had an increased risk of incident fractures at any site (RR 1.69; 95% CI, 1.13 to 2.53); major site, including the femur, radius, ulnar, vertebral, rib, and humerus (RR 2.17; 95% CI 1.12 to 4.22); and vertebral site (RR 6.44, 95% CI, 1.64 to 25.33) compared with those with pain at zero to two sites. These associations remained statistically significant after further adjustment for falls risk and BMD. Pain at multiple sites was associated with incident fracture risk in a dose-response manner, suggesting that widespread pain is an independent contributor to fracture risk. The potential for pain management in fracture prevention warrants further exploration. © 2019 American Society for Bone and Mineral Research.

Prevalence of and factors associated with dysfunctional low back pain in patients with rheumatoid arthritis

PURPOSE

To investigate the prevalence of and factors associated with dysfunctional low back pain (LBP) in patients with rheumatoid arthritis (RA).

METHODS

This cross-sectional study included 1276 RA outpatients from two hospitals. The Roland-Morris Disability Questionnaire was used to address the functional-dysfunctional state criterion. Clinical variables, such as medical status, disease activity, bone mineral density, and spinopelvic alignment parameters, were compared between patients with and without dysfunctional LBP.

RESULTS

Mean age and disease duration were 64.6 and 13.4 years, respectively; the prevalence of dysfunctional LBP was 32.8%. On univariate analysis, significant differences existed in many variables, except sex, body weight, C-reactive protein (CRP) level, and prevalence of biological agent users, between patients with and without dysfunctional LBP. Multivariate logistic regression analysis revealed body mass index (BMI; odds ratio [OR], 1.116; P < 0.001), onset age of RA (OR, 1.020; P = 0.020), disease duration of RA (OR, 1.043; P < 0.001), methotrexate (MTX) use (OR, 0.609; P = 0.007), vertebral fractures (OR, 2.189; P = 0.001), vertebral endplate and/or facet erosion (OR, 1.411; P = 0.043), disease activity score (DAS) in 28 joints-CRP (DAS-28CRP) (OR, 1.587; P = 0.001), pelvic tilt (PT; OR, 1.023; P = 0.019), and sagittal vertical axis (SVA; OR, 1.007; P = 0.043) as associated factors.

CONCLUSION

The factors associated with dysfunctional LBP in patients with RA were more vertebral fractures, higher DAS-28CRP, vertebral endplate and/or facet erosion, higher BMI, longer disease duration, greater PT, older onset age, greater SVA, and less MTX use. Strictly controlling patients' body weight and disease activity with MTX and avoiding spinopelvic malalignment through vertebral fracture prevention are important. These slides can be retrieved under Electronic Supplementary Material.

Improvement of spinal alignment and quality of life after corrective surgery for spinal kyphosis in patients with osteoporosis: a comparative study with non-operated patients

This study evaluated changes in spinal alignment and quality of life (QOL) after corrective spinal surgery for patients with postmenopausal osteoporosis and spinal kyphosis. Spinal global alignment and QOL were significantly improved after corrective spinal surgery but did not reach the level of non-operated controls.

INTRODUCTION

With the increased aging of society, the demand for corrective spinal instrumentation for spinal kyphosis in osteoporotic patients is increasing. However, previous studies have not focused on the improvement of quality of life (QOL) after corrective spinal surgery in patients with osteoporosis, compared to non-operated control patients. The purposes of this study were thus to evaluate changes in spinal alignment and QOL after corrective spinal instrumentation for patients with osteoporosis and spinal kyphosis and to compare these results with non-operated patients.

METHODS

Participants comprised 39 patients with postmenopausal osteoporosis ≥50 years old who underwent corrective spinal surgery using multilevel posterior lumbar interbody fusion (PLIF) for symptomatic thoracolumbar or lumbar kyphosis, and 82 age-matched patients with postmenopausal osteoporosis without prevalent vertebral fractures. Spinopelvic parameters were evaluated with standing lateral spine radiography, and QOL was evaluated with the Japanese Osteoporosis QOL Questionnaire (JOQOL), SF-36, and Roland-Morris Disability Questionnaire (RDQ).

RESULTS

Lumbar kyphosis angle, sagittal vertical axis, and pelvic tilt were significantly improved postoperatively. QOL evaluated with all three questionnaires also significantly improved after 6 months postoperatively, particularly in domain and subscale scores for pain and general/mental health. However, these radiographic parameters, total JOQOL score, SF-36 physical component summary score, and RDQ score were significantly inferior compared with non-operated controls.

CONCLUSIONS

The results indicate that spinal global alignment and QOL were significantly improved after corrective spinal surgery using multilevel PLIF for patients with osteoporosis and spinal kyphosis but did not reach the level of non-operated controls.

Pain and falls and fractures in community-dwelling older men

BACKGROUND

Pain may reduce stability and increase falls and subsequent fractures in older men.

OBJECTIVES

To examine the association between joint pain and any pain with falls, hip and non-spine fractures in older community-dwelling men.

DESIGN

A cohort study.

SETTING AND PARTICIPANTS

Analyses included 5,993 community-dwelling men aged ≥65 years from the MrOS cohort.

MEASUREMENTS

Pain at hip, knee and elsewhere (any) was assessed by self-report. Men reported falls via questionnaires mailed 3× per year during the year following the baseline visit. Fractures were verified centrally. Mean follow-up time for fractures was 9.7 (SD 3.1) years. Logistic regression models estimated likelihood of falls and proportional hazards models estimated risk of fractures. Models were adjusted for age, BMI, race, smoking, alcohol use, medications use, co-morbidities and arthritis; fracture models additionally adjusted for bone mineral density.

RESULTS

One quarter (25%, n = 1,519) reported ≥1 fall; 710 reported ≥2 falls in the year after baseline. In multivariate models, baseline pain at hip, knee or any pain increased likelihood of ≥1 fall and ≥2 falls over the following year. For example, knee pain increased likelihood of ≥1 fall (odds ratio, OR 1.44; 95% confidence interval, CI 1.25-1.65) and ≥2 falls (OR 1.75; 95% CI 1.46-2.10). During follow-up, 936 (15.6%) men suffered a non-spine fracture (n = 217, 3.6% hip). In multivariate models, baseline pain was not associated with incident hip or non-spine fractures.

CONCLUSIONS

Any pain, knee pain and hip pain were each strong independent risk factors for falls in older men. Increased risk of falls did not translate into an increased risk of fractures.

Serum 25-hydroxyvitamin D below 25 ng/mL is a risk factor for long bone fracture comparable to bone mineral density in Japanese postmenopausal women

There is emergent evidence for divergent associations between 25(OH)D levels and fractures by race and ethnicity, but data on Asian populations are sparse. We investigated this association in a primary care cohort of 1470 postmenopausal Japanese women followed for a mean period of 7.2 years and explored a potential threshold of 25(OH)D. Endpoints were incident vertebral, proximal femur, and long bone fractures. Rate ratios were estimated using multivariate Poisson regression adjusted for lumbar or femur bone mineral density (BMD) less than -2.5 SD of the young adult mean (YAM), age, weight, presence of diabetes mellitus, parathyroid hormone, estimated glomerular filtration rate, prior fracture, back pain, present medications and past medical history. Mean age was 63.7 ± 10.7 years and osteoporosis patients were 41.3 %. The background data of the present participants were almost identical to the subjects participating in the National Health and Nutrition Survey of 2003. Overall, 49.6 % of the subjects had a 25(OH)D value <20 ng/mL and 27.8 % had a 25(OH)D value from 20 to 24 ng/mL. The propensity score for exposure to 25(OH)D < 25 ng/mL in the present and independent community dwelling populations, namely the Miyama and Taiji cohorts, were not significantly different, suggesting no evidence for selection bias. The generalized additive models showed clear decreasing trends in incidence rates of proximal femur and long bone fractures at higher levels of 25(OH)D, and the annual incidence rate of proximal femur fracture was around 0.0005 in women with 25(OH)D > 25 ng/mL, probably leading to the decreasing trend in long bone fracture. Multivariate-adjusted rate ratios of 25(OH)D < 25 ng/mL were 1.01 (95 % confidence interval [CI], 0.84-1.22, p = 0.88) for vertebral fracture, 2.71 (95 % CI 0.94-7.83, p = 0.07) for proximal femur fracture, and 2.20 (95 % CI 1.37-3.53, p < 0.01) for long bone fracture. The respective rate ratios of a BMD level lower than -2.5 SD of the YAM were 1.61 (95 % CI 1.33-1.94, p < 0.01), 1.52 (95 % CI 0.67-3.45, p = 0.32), and 1.54 (95 % CI 1.02-2.33, p = 0.04). In conclusion, 25(OH)D is a leading risk factor for long bone fracture comparable to BMD in Japanese postmenopausal women. The contribution of 25(OH)D to fracture risks is substantial even below 25 ng/mL and is possibly site-specific. We recommend measuring the serum 25(OH)D level in primary care settings.

Evaluation of bone mineral density in patients with chronic low back pain

Study Design

This was designed as a retrospective study.

Purpose

We investigated the relationship between bone mineral density (BMD) and chronic lower back pain (LBP).

Overview of Literature

In spite of a large number of epidemiological surveys on the prevalence of LBP and BMD measurements completed separately in the general population, the relationship between the two has not been well documented.

Methods

The study included 171 patients with chronic LBP who underwent the BMD study. The control group was selected from our database regarding BMD without LBP.

Results

A total of 678 subjects, aged 18 to 100 years (mean, 49.9±12.9 years) were included in the study, 25% (n=171) of the subjects had LBP. Compared to those patients without LBP, patients exhibiting LBP had statistically significant lower mean weight, hip and spine BMD and T-score. Lower BMD and T-scores were significant regardless of the age group, gender, menopausal status, and obesity classification.

Conclusions

Chronic LBP has a negative correlation with hip and spine bone mineral density.

Overweight/obesity and underweight are both risk factors for osteoporotic fractures at different sites in Japanese postmenopausal women

This cohort study of 1,614 postmenopausal Japanese women followed for 6.7 years showed that overweight/obesity and underweight are both risk factors for fractures at different sites. Fracture risk assessment may be improved if fracture sites are taken into account and BMI is categorized.

INTRODUCTION

The effect of body mass index (BMI) on fracture at a given level of bone mineral density (BMD) is controversial, since varying associations between BMI and fracture sites have been reported.

METHODS

A total of 1,614 postmenopausal Japanese women were followed for 6.7 years in a hospital-based cohort study. Endpoints included incident vertebral, femoral neck, and long-bone fractures. Rate ratios were estimated by Poisson regression models adjusted for age, diabetes mellitus, BMD, prior fracture, back pain, and treatment by estrogen.

RESULTS

Over a mean follow-up period of 6.7 years, a total of 254 clinical and 335 morphometric vertebral fractures, 48 femoral neck fractures, and 159 long-bone fractures were observed. Incidence rates of vertebral fracture in underweight and normal weight women were significantly lower than overweight or obese women by 0.45 (95 % confidence interval: 0.32 to 0.63) and 0.61 (0.50 to 0.74), respectively, if BMD and other risk factors were adjusted, and by 0.66 (0.48 to 0.90) and 0.70 (0.58 to 0.84) if only BMD was not adjusted. Incidence rates of femoral neck and long-bone fractures in the underweight group were higher than the overweight/obese group by 2.15 (0.73 to 6.34) and 1.51 (0.82 to 2.77) and were similar between normal weight and overweight/obesity.

CONCLUSIONS

Overweight/obesity and underweight are both risk factors for fractures at different sites. Fracture risk assessment may be improved if fracture sites are taken into account and BMI is categorized.

Urinary pentosidine improves risk classification using fracture risk assessment tools for postmenopausal women

We investigated whether measurement of pentosidine, in addition to the conventional risk assessment tool, the Fracture and Immobilization Score (FRISC), improves early identification of fracture cases. A total of 765 postmenopausal Japanese women with baseline measurement of urinary pentosidine were followed in a hospital-based cohort study. Endpoints were incidence of vertebral fracture, incidence of long bone fracture, and incidence of long bone and vertebral fracture. To assess the effect of pentosidine on fracture risk, we fitted multivariate Cox regression models adjusted for age, body weight, diabetes mellitus, lumbar BMD, prior fracture, and presence of back pain. To explore potential nonlinear relationships, we fitted a multivariate generalized additive model. To assess the discriminatory power of pentosidine, we performed receiver operating characteristic analysis. The hazard ratios for a 1 SD increase in pentosidine were 1.18 (95% CI 1.05-1.33, p < 0.01) for vertebral fracture and 1.20 (95% CI 1.07-1.33, p < 0.01) for long bone and vertebral fractures. The relationship was approximately linear, and there was no indication of the presence of a threshold. The C statistics were 0.732 (95% CI 0.686-0.778) for the model with both pentosidine and the 10-year risk and 0.702 (95% CI 0.654-0.750) for the 10-year risk alone. Eighty-three subjects (11%) in the whole cohort were in the highest quartile of pentosidine, although their 10-year risks were less than 15% and included 17 incident vertebral fracture cases. Urinary pentosidine improves risk classification using conventional risk assessment tools. Optimal clinical strategies of diagnosis and treatment remain uncertain and in need of additional investigation.

Clinical characteristics and incidence of first fracture in a consecutive sample of post-menopausal women attending osteoporosis centers: The PROTEO-1 study

BACKGROUND

Osteoporosis is a highly prevalent disease and fractures are a major cause of disability and morbidity.

AIM

The purpose of this study was to characterize post-menopausal women attending osteoporosis centers in Italy, to evaluate physician management, and to determine the incidence of first osteoporotic fracture.

SUBJECTS AND METHODS

PROTEO-1 was an observational longitudinal study with a 12-month follow-up. Data were collected from women attending osteoporosis centers. Women without prevalent fracture were eligible to enter the 1-yr follow-up phase: the clinical approach to patients according to their fracture risk profile and the incidence of fracture were recorded.

RESULTS

4269 patients were enrolled in 80 centers in the cross-sectional phase; 34.2% had an osteoporotic fracture at baseline. Patients with prevalent fractures were older and more likely to be treated compared with non-fractured patients. The incidence of vertebral or hip fracture after 1 yr was 3.84%, regardless of the calculated risk factor profile, and was significantly higher in patients with back pain at baseline (4.2%) compared with those without back pain (2.2%; p=0.023). Generally, physicians prescribed more blood exams and drugs to patients at higher risk of fracture. Among fractured patients only 24% were properly treated; the rate of non-responders to treatment was about 4%.

CONCLUSIONS

In a large, unselected sample of post-menopausal women attending osteoporosis centers, those without previous fracture were at substantial risk of future fracture, regardless of their theoretical low 10-yr fracture risk. The presence of back pain in women without previous fracture warrants close attention.

Established osteoporosis associated with high mortality after adjustment for age and co-mobidities in postmenopausal Japanese women

OBJECTIVE

Osteoporosis has been reported to increase the risk of mortality. However, these reports did not evaluate the effects of co-mobidities and the severity of osteoporosis on mortality. The aim of our study was to determine whether or not major osteoporotic fractures contribute to the increased mortality risk in Japanese women.

METHOD

We conducted a prospective observational study. Risk factors contributing to mortality were assessed by Cox's proportional hazard model.

SUBJECTS

A total of 1,429 ambulatory postmenopausal female volunteers aged over 50 years old were enrolled in the study. Information was obtained from the subjects on baseline biochemical indices, bone mineral density (BMD), prevalent fractures, and co-morbidities. Mortality was assessed and confirmed by the certificates or hospital records. The subjects were classified into three categories in accordance with or without osteoporosis. The osteoporotic group was further categorized by the basis of the presence or absence of major osteoporotic fractures.

RESULTS

Mean age and SD of the participants were 66.5±9.3 (50-90) years old. The participants were followed for a total of 4.5±3.5 years (mean ± SD) and a total of 141 participants (9.9%) died during the observation. In addition to the traditional risks for mortality, such as age (Hazard ratio, 2.817, 95% CI, 2.237-3.560, p<0.0001), BMI (HR 0.504, 0.304-0.824, p=0.0061), prevalent malignancies (HR 2.885, 1.929-4.214, p<0.0001), dementia (HR 1.602, 1.027-2.450, p=0.038) and cardio-vascular disease (HR 1.878, 1.228-2.787, p=0.0043), the serum level of creatinine (HR 2.451, 1.107-5.284, p=0.027) and severity of osteoporosis (HR 1.390, 1.129-1.719, P=0.0018) were found to be significant independent risk factors for all-cause mortality.

CONCLUSION

These results emphasize the importance of osteoporotic fracture in terms of survival.

The Fracture and Immobilization Score (FRISC) for risk assessment of osteoporotic fracture and immobilization in postmenopausal women--A joint analysis of the Nagano, Miyama, and Taiji Cohorts

INTRODUCTION

We aimed to (i) explore risk factors for major osteoporotic fracture or immobilization; (ii) develop a prediction model that can be used to assess the risk of fracture and immobilization; and (iii) assess external validity of the final model.

METHODS

A total of 1787 postmenopausal Japanese women were followed in a hospital-based cohort study. Endpoints included the annual incidence of major osteoporotic fracture and immobilization. For each endpoint, multivariate Poisson regression models were fitted separately and risk factors were screened through backward variable selection. The predictive accuracy of the final model (FRISC) was evaluated in two independent community-based cohorts.

RESULTS

Over a median follow-up of 5.3 years, a total of 383 major osteoporotic fractures (279 clinical vertebral, 44 hip, 60 distal forearm) and 83 immobilizations occurred in the developmental dataset. Backward variable selection confirmed that the following are risk factors for major osteoporotic fracture: age, weight, prior fracture, back pain, and lumbar bone mineral density (BMD). Age, prior fracture and dementia were significant risk factors for immobilization. Hosmer-Lemeshow tests did not indicate any significant deviation between the observed fracture frequency and prediction from the FRISC in the independent validation dataset. The C statistic for the FRISC was 0.727 (95% confidence interval: 0.660 to 0.794) and was higher than that for BMD alone significantly (p=0.03).

CONCLUSIONS

We developed a novel prediction model for fracture and immobilization, FRISC, and the clinical risk factors in the FRISC allows better identification of populations at high risk of fracture than BMD alone. A web application is available at http://www.biostatistics.jp/prediction/frisc.