Associations of self-reported height loss and kyphosis with vertebral fractures in Japanese women 60 years and older: a cross-sectional survey

Height Loss Is an Independent Predictor of Fracture Incidence in Postmenopausal Women: The Results from the Gliwice Osteoporosis Study (GO Study)

BACKGROUND

The aim of a longitudinal, retrospective study was to establish variables predicting fracture incidence over a decade.

METHODS

The study sample comprises a group of 457 postmenopausal women aged over 55 years, recruited from the database of an outpatient osteoporotic clinic. Several variables with potential influence on bone status, including the measurement of body height and hip bone densitometry, were collected. BMD at the femoral neck (FN BMD) was established using a Prodigy device (Lunar, GE, USA). Current body height was compared with the maximal historical body height in early adulthood, as reported by the patient.

RESULTS

Three hundred and ninety-four women did not have fractures during the follow up, and 63 subjects presented fractures. Subjects with fracture had lower FN BMD with a T-score of -1.86 ± 1.04 compared to -1.44 ± 0.89 in those without fractures (p < 0.001). Mean height loss (HL) was 3.47 ± 2.11 cm in fractured subjects and 2.50 ± 2.47 cm in unfractured ones, and differed significantly, p < 0.01. Fracture incidence was significantly related to age, rheumatoid arthritis, falls, and previous fractures. In the multivariable analysis using logistic regression, FN BMD, baseline fracture, and HL were identified as the significant predictors of fractures of follow up.

CONCLUSIONS

Osteoporotic fractures in postmenopausal women were predicted by FN BMD, prior fracture(s), and HL easily established during physical examination.

Loss of height predicts fall risk in elderly Japanese: a prospective cohort study

INTRODUCTION

The purpose of this study was to explore whether height loss is associated with future falls and whether the combination of height loss and fall experience is associated with future falls.

MATERIALS AND METHODS

In this prospective observational study, a total of 765 individuals (354 men, 411 women) agreed to join the study. Baseline data on demographics, comorbidities, physical performance, and previous falls were assessed. Height loss was calculated as the difference between the self-reported height at a younger age and the current height and was divided into two groups: < 2 cm and ≥ 2 cm. Approximately 15 months after the baseline evaluation, follow-up questionnaires were used to assess the fall history. Participants were classified as either "non-fallers" or "fallers." Multiple logistic regression was used to evaluate the association between falls and each factor and to obtain adjusted odds ratio estimates.

RESULTS

The follow-up questionnaire was returned by 668 participants, 74 of whom (11.1%) fell at least once during the observation period. Multiple logistic regression analysis found that height loss of > 2 cm was a significant predictor of future falls, even after adjusting for other factors. Additionally, the combination of height loss and previous falls was a risk factor for falls.

CONCLUSIONS

We suggest that height loss of ≥ 2 cm is a predictor of future falls in older adults, and the combination of height loss and fall experiences may be a useful screening tool for determining fall risk.

Current Status of the Diagnosis and Management of Osteoporosis

Osteoporosis has been defined as the silent disease of the 21st century, becoming a public health risk due to its severity, chronicity and progression and affecting mainly postmenopausal women and older adults. Osteoporosis is characterized by an imbalance between bone resorption and bone production. It is diagnosed through different methods such as bone densitometry and dual X-rays. The treatment of this pathology focuses on different aspects. On the one hand, pharmacological treatments are characterized by the use of anti-resorptive drugs, as well as emerging regenerative medicine treatments such as cell therapies and the use of bioactive hydrogels. On the other hand, non-pharmacological treatments are associated with lifestyle habits that should be incorporated, such as physical activity, diet and the cessation of harmful habits such as a high consumption of alcohol or smoking. This review seeks to provide an overview of the theoretical basis in relation to bone biology, the existing methods for diagnosis and the treatments of osteoporosis, including the development of new strategies.

Height loss in postmenopausal women-do we need more for fracture risk assessment? Results from the GO Study

Human body height loss of 3-4 cm or more may be considered a simple indicator of increasing fracture risk, where the information is very similar to the results from fracture risk assessments by available online calculators, all of them based on a multiple variable approaches.

INTRODUCTION

The aim of the study was to assess the relationship between body height loss (HL) and fracture risk in postmenopausal women from the Gliwice Osteoporosis (GO) Study.

METHODS

The study sample included 1735 postmenopausal women, aged over 55 years and recruited at the Osteoporotic Outpatient Clinic. The mean age of the study participants was 68.15 ± 8.16 years. Fracture risk was established, using the fracture risk assessment tool (FRAX) (10-year probability of major and hip fractures), the Garvan calculator (any and hip fractures, 5 and 10 years) and the Polish (POL-RISK) algorithm, available at www. fracture - risk .pl (any fractures, 5 years). Bone densitometry at the femoral neck was performed, using a Prodigy device (Lunar, GE, USA). Body heights were measured before bone densitometry, using a wall stadiometer and compared with the maximum body heights, measured in early adulthood and reported by the study participants themselves.

RESULTS

In 199 women, the body heights, measured during the study, did not change in comparison to their corresponding values in early adulthood, while being decreased in the other 1536 women. The mean height loss (HL) in the whole study group was 3.95 ± 3.24 cm. That HL correlated significantly with the calculated fracture risk (the r range from 0.13 to 0.39, p < 0.0001). In general, regarding the patients with fracture risk close to the recommended therapeutic thresholds, HL was around 3-4 cm, except of the values from the FRAX calculator for major fractures, where the commonly used therapeutic threshold (20%) was related to HL of approximately 6.5 cm. In subjects with HL between 3.5 and 4 cm (n = 208), the FRAX value for major fractures was 6.83 ± 3.74.

CONCLUSIONS

Body height measurements, carried out to establish HL, provide an important information for clinical practice, where HL of 3-4 cm or more may be considered a simple indicator of increasing fracture risk.

Utility of fragility fracture prediction tools in a group of postmenopausal women

Objectives

Fractures are a common complication of osteoporosis. The main aim of our study was to assess the relation between fractures identified as low energy fractures (fragility), bone mineral density (BMD), trabecular bone score (TBS), and handgrip in a group of postmenopausal women. An additional aim was to determine the relation between fragility fractures and age, height loss, and falls (reported in the last 12 months and 5 years).

Material and methods

The study was conducted in a group of 120 (mean age 69 years; 59-81, SD 5.3) postmenopausal patients who were referred to the Medical Centre for an osteoporosis screening appointment by their general practitioner. All patients were interviewed (with a questionnaire containing questions on fracture risk factors and highest height), had their anthropometric measures taken (current height and weight) as well as TBS analysis following their DXA (dual-energy X-ray absorptiometry) scan and handgrip measure.

Results

Sixty patients from the study group had a history of fractures (with a total of 92 fractures), of whom 39 women (76 fractures) were identified as those with a low-energy fracture. Fragility fractures were more likely to be reported in older patients (Me 71 vs. 68 years, p < 0.05). Differences observed between TBS, handgrip and BMD in reference to fragility fractures were not statistically significant. Analysis showed significant correlations between BMD (neck and L1-L4) and TBS fracture risk categories. Falls reported in the last 5 years and height loss were factors which correlated with fragility fractures (p < 0.05).

Conclusions

Risk of fragility fractures increases with age. Bone mineral density is insufficient as a fracture risk assessment tool. Information on falls and height loss may provide additional data on fracture risk assessment.

The significance of height loss in postmenopausal women. The results from GO Study

BACKGROUND

The aim of the study was the assessment of clinical significance of height loss (HL) in female population.

MATERIAL

The study cohort was recruited from GO Study. Data from 1735 postmenopausal women aged over 55 years (mean age 68.15 ± 8.16 years) were analysed.

METHODS

Data on clinical risk factors for osteoporosis and fractures were collected. Bone densitometry at hip was performed using a device Prodigy (GE, USA). Height was established using stadiometer and was compared with maximal height in early adulthood.

RESULTS

The mean HL was 3.9 ± 3.2 cm. HL was significantly higher in women with fractures in comparison with those without fracture (4.9 ± 3.6 cm vs 3.4 ± 2.8 cm; P < .0001). HL increased with the number of fractures, and was 4.1 ± 3.2 cm, 5.3 ± 3.5 cm and 6.7 ± 4.1 cm in women with one, two and three or more fractures respectively. Women with spine fractures presented with HL higher in comparison with all the other subjects (6.3 ± 4.0 vs 3.6 ± 2.9 cm, P < .0001) and women with all non-spine fractures (6.3 ± 4.0 vs 4.0 ± 3.0 cm, P < .0001). In women with steroid use and falls, HL was significantly greater than in subjects without this factor. HL correlated significantly with age and BMI (positively) and current height (negatively). Mean T-score for FN BMD was -1.75 ± 0.9 and correlate significantly with HL (r = -.21, P < .0001). For the HL threshold above 4 cm, the fracture incidence was above 50%.

CONCLUSION

Height loss value is a simple and very informative measure describing fracture risk and functional status in postmenopausal women. HL exceeding 4 cm is related to fracture probability above 50%.

Vertebral compression fractures: Still an unpredictable aspect of osteoporosis

Vertebral compression fracture is a hallmark of osteoporosis (OP) and by far the most prevalent fragility fracture. It is well proven that patients who develop a vertebral compression fracture are at substantial risk for additional fractures. Diagnosis is based on adequate clinical evaluation, imaging, and laboratory tests. The imaging of OP and fragility fractures includes conventional radiology to evaluate spinal fractures, bone mineral density (BMD) testing by dual energy x-ray densitometry, quantitative computerized tomography, magnetic resonance imaging, bone scintigraphy (if necessary), and ultrasound. Screening and treatment of individuals with high risk of osteoporotic fracture are cost-effective, but approximately two-thirds of the vertebral compression fractures (VCF) that occur each year are not accurately diagnosed and, therefore, not treated. Evaluation of VCFs, even though they may be asymptomatic, seems essential to health-related and/or clinical research on OP.

Spinal Osteoarthritis Is Associated With Stature Loss Independently of Incident Vertebral Fracture in Postmenopausal Women

STUDY DESIGN

Retrospective observational study from the Nagano Cohort Study.

OBJECTIVE

Clarify the association between spinal osteoarthritis and loss of stature in postmenopausal women.

SUMMARY OF BACKGROUND DATA

Loss of stature with aging is known to deteriorate health-related quality of life and has been implicated with increased mortality. Although the association of vertebral fracture with height loss has been well documented, the relationship between stature loss and spinal osteoarthritis remains unclear.

METHODS

We retrospectively investigated Japanese postmenopausal women recruited from the Nagano Cohort Study. The participants were outpatients at a primary care institute in Nagano prefecture, Japan. A total of 977 postmenopausal patients (mean age: 65.8 yr) completed a minimum of 1 year of follow-up, with an average observation period of 7.6 years. Quartile analysis on the prevalence of spinal osteoarthritis and occurrence of incident fracture was performed based on the rate of stature change per year (Δ cm/yr). Multiple regression analysis was also conducted to identify the determinants of stature change.

RESULTS

The lower quartiles of stature change rate (i.e., more rapid stature loss) displayed a significantly higher prevalence of spinal osteoarthritis (P < 0.001) and incident vertebral fracture (P < 0.001). A statistically significant independent negative association for spinal osteoarthritis prevalence with change in stature was revealed by multiple regression analysis after adjusting for confounders including incident vertebral fracture. The partial regression coefficient for spinal osteoarthritis was -0.18 (95% confidence interval -0.33 to -0.03; P = 0.016).

CONCLUSION

This study demonstrated an independent association of spinal osteoarthritis with stature loss in postmenopausal women. Adequate understanding of this relationship and appropriate treatment approaches will help improve health-related quality of life in elderly patients.

LEVEL OF EVIDENCE

3.

Association of height loss with falls and sarcopenia in community-dwelling older women

Objectives

Height loss is associated with vertebral fracture risk and osteoporosis. We assumed that height loss may indicate the risk of falls because the presence of osteoporosis is significantly associated with sarcopenia development. We studied the association of height loss with falls and sarcopenia.

Methods

This study included 610 community-dwelling women. We measured the height, weight, appendicular skeletal muscle mass index (ASMI), grip strength, and gait speed. Additionally, we recorded the individual’s tallest height, and the presence or absence of single or multiple falls during the preceding 12 months. The participants were classified into nonheight loss, 2- to 3-cm height loss, 3- to 4-cm height loss, and over 4-cm height loss groups. The association of height loss with falls and sarcopenia were examined using multiple logistic regression analysis.

Results

We found that 3- to 4-cm height loss and over 4-cm height loss were significantly associated with falls (odds ratio [OR], 1.637; 95% confidence interval [CI], 1.023–2.619; P = 0.04), (OR, 1.742, 95% CI, 1.054–2.877; P = 0.03), respectively. Additionally, over 4-cm height loss was significantly associated with sarcopenia for ASMI calculated by participant’s tallest recalled height squared (OR, 2.676; 95% CI, 1.122–6.284; P = 0.026).

Conclusions

We found that the risk of falls was advanced at 3- to 4-cm height loss and over 4-cm height loss, and sarcopenia started at over 4-cm height loss. Height loss may be a useful indicator of the risk of falls and sarcopenia.

Adult spinal deformity and its relationship with height loss: a 34-year longitudinal cohort study

Background

Age-related height loss is a normal physical change that occurs in all individuals over 50 years of age. Although many epidemiological studies on height loss have been conducted worldwide, none have been long-term longitudinal epidemiological studies spanning over 30 years. This study was designed to investigate changes in adult spinal deformity and examine the relationship between adult spinal deformity and height loss.

Methods

Fifty-three local healthy subjects (32 men, 21 women) from Furano, Hokkaido, Japan, volunteered for this longitudinal cohort study. Their heights were measured in 1983 and again in 2017. Spino-pelvic parameters were compared between measurements obtained in 1983 and 2017. Individuals with height loss were then divided into two groups, those with degenerative spondylosis and those with degenerative lumbar scoliosis, and different characteristics were compared between the two groups.

Results

The mean age of the subjects was 44.4 (31–55) years at baseline and 78.6 (65–89) years at the final follow-up. The mean height was 157.4 cm at baseline and 153.6 cm at the final follow-up, with a mean height loss of 3.8 cm over 34.2 years. All parameters except for thoracic kyphosis were significantly different between measurements taken in 1983 and 2017 (p < 0.05). Height loss in both sexes was related to changes in pelvic parameters including pelvic incidence-lumbar lordosis (R = 0.460 p = 0.008 in men, R = 0.553 p = 0.012 in women), pelvic tilt (R = 0.374 p = 0.035 in men, R = 0.540 p = 0.014 in women), and sagittal vertical axis (R = 0.535 p = 0.002 in men, R = 0.527 p = 0.017 in women). Greater height loss was more commonly seen in women (p = 0.001) and in patients with degenerative lumbar scoliosis (p = 0.02).

Conclusions

This longitudinal study revealed that height loss is more commonly observed in women and is associated with adult spinal deformity and degenerative lumbar scoliosis. Height loss is a normal physical change with aging, but excessive height loss is due to spinal kyphosis and scoliosis leading to spinal malalignment. Our findings suggest that height loss might be an early physical symptom for spinal malalignment.

Height loss but not body composition is related to low back pain in community-dwelling elderlies: Shimane CoHRE study

Background

Low back pain (LBP) is a common complaint in the elderly Japanese population. Although previous studies showed that height loss was associated with LBP, it remains unclear whether LBP is associated with body composition. The objective of the present study was to investigate whether body composition and physical characteristics, including height loss, were associated with LBP.

Methods

The present study is retrospectively registered, and the participants were 2212 community-dwelling Japanese people aged over 60 years who participated in the Shimane CoHRE study in 2016. We investigated the presence of LBP, body composition parameters (muscle, fat, body weight, and bone mass), physical characteristics (body height and height loss), chronic diseases, history of fall, smoking, and drinking habits. We examined the relationships of body composition parameters and physical characteristics with point prevalence of LBP using multivariate logistic regression.

Results

The point prevalence of LBP was 43.2% in women and 39.5% in men. Logistic regression models showed that body height and body composition were not significantly associated with LBP; however, height loss was associated significantly with LBP in women and men (OR: 1.14, 95% CI: 1.08–1.20 and OR: 1.13, 95% CI: 1.06–1.21, respectively). Hypertension (OR: 1.32, 9 5% CI: 1.04–1.69) and chronic heart disease (OR: 1.57, 95% CI: 1.01–2.43) in women and history of fall (OR: 1.70, 95% CI: 1.13–2.56) and cerebrovascular disease (OR: 1.88, 95% CI: 1.05–3.34) in men were significantly associated with LBP. However, body composition was not associated with LBP in either gender.

Conclusions

The present study demonstrated that height loss, but not body composition, was related to LBP in community-dwelling elderly people. To elucidate the cause of LBP, it is important to consider the relationship with height loss.

Electronic supplementary material

The online version of this article (10.1186/s12891-019-2580-6) contains supplementary material, which is available to authorized users.

Long waiting time before tooth extraction may increase delayed wound healing in elderly Japanese

In osteoporosis patients receiving antiresorptive medications, stopping the drug and delaying tooth extraction has been suggested to reduce the risk of osteonecrosis of the jaw (ONJ). However, postponing tooth extraction for ≥ 2 months was associated with an increased risk of delayed wound healing beyond 8 weeks after extraction, a risk factor for developing ONJ.

INTRODUCTION

A long waiting time before tooth extraction could result from concern about a potential increased risk of osteonecrosis of the jaw (ONJ) in osteoporosis patients. We clarified whether a long waiting time before tooth extraction during the past year may be associated with an increased risk of delayed wound healing beyond 8 weeks after tooth extraction, which may be a risk factor of ONJ.

METHODS

Of 5639 patients aged ≥ 60 years who visited our 20 clinics or hospitals and answered a structured questionnaire, 426 patients (151 men, 275 women) aged 60-96 years comprised the final participants in this study. Self-reported kyphosis was used as a surrogate marker of vertebral fractures. Stepwise logistic regression analysis, adjusted for covariates, was used to calculate the odds ratio (OR) and the 95% confidence interval (CI) for the presence of delayed wound healing longer than 8 weeks after tooth extraction during the past year based on the duration before extraction.

RESULTS

Subjects who had waited > 2 months for tooth extraction had a significantly higher risk of delayed wound healing compared with those whose tooth was extracted within 1 month (OR = 7.23; 95% CI = 2.19-23.85, p = 0.001) regardless if antiresorptive medications for osteoporosis were used. The presence of self-reported kyphosis was significantly associated with an increased risk of delayed wound healing (OR = 5.08; 95% CI = 1.11-23.32, p = 0.036).

CONCLUSIONS

A long waiting time before tooth extraction may be a risk factor for delayed wound healing beyond 8 weeks after extraction in patients aged ≥ 60 years.

Height Loss Was Associated With Osteoporosis in Korean Elderly Men, Not in Women: The Korea National Health and Nutrition Examination Survey 2008-2010

The degree of height loss varies among individuals, and excessive height loss can be a vertebral fracture or bone loss manifestation. The objective of this study was to examine the relationships between height loss and bone mineral density (BMD) and to assess the prevalence of osteoporosis according to the height loss quartiles. Data from the Korea National Health and Nutrition Examination Survey were analyzed. A total of 2799 participants more than 60 years old were included and subdivided into quartiles according to height loss (Q1-Q4). Height loss was calculated with the difference between the self-reported maximum adult height and the actual measured height. BMD was measured by dual-energy X-ray absorptiometry at the total femur (TF), femoral neck, and lumbar spine. Multivariable linear and logistic regression analyses were conducted to study the height loss-BMD and the height loss-osteoporosis prevalence relationships, respectively. After adjustments for all covariates, height loss was negatively associated with BMD at all the 3 sites (TF and lumbar spine, p < 0.001; femoral neck, p = 0.002) in men, but only at TF (p = 0.008) in women. Men with Q4 height loss had an increased prevalence of osteoporosis compared with those with Q1 (odds ratio = 2.092 and 95% confidence interval = 1.076-4.068). In women, the prevalence of osteoporosis was not associated with height loss. In conclusion, Q4 height loss in elderly men was associated with the increased prevalence of osteoporosis in Korea.

Spinal radiographs in those with back pain-when are they appropriate to diagnose vertebral fractures?

The presence of an osteoporotic vertebral fracture improves fracture risk assessment and may change management, so it is vital for healthcare professionals to assess patients for the presence or absence of these fractures. This may be particularly important in the presence of back pain. However, the correlation between low back symptoms and spinal imaging results is poor and the pathophysiology of most low back pain is not known, leading to a common conclusion that spinal radiographs are not appropriate for the assessment of back pain. For individual patients with back pain, spinal radiographs should be considered if they have certain features in the history and examination. As well as the traditional risk factors for osteoporosis, self-reported descriptives of back pain and novel physical examination findings have been shown to make the presence of vertebral fractures more likely. Systematic approaches have the potential to improve bone health across the population but need to be targeted to be cost-effective. Spinal radiographs should be considered for individual older patients with back pain if they have certain additional features in the history and examination.

Antiresorptive agent-related osteonecrosis of the jaw in osteoporosis patients from Asian countries

Bisphosphonate (BP)-associated osteonecrosis of the jaw (ONJ) was first reported in oncology patients in 2003 and subsequently in osteoporosis patients in 2004. Since oral surgical procedures, such as tooth extraction, are also considered one of the major risk factors for ONJ, there is confusion among physicians, dentists, and patients—particularly osteoporosis patients currently taking BPs—regarding the safety of remaining on therapy surrounding these procedures. Many papers about BP-related ONJ (BRONJ) have been published to date. In addition to BRONJ, recent studies have reported an association between ONJ and the antiresorptive therapy denosumab (Dmab; a RANKL-inhibitor). BRONJ and Dmab-related ONJ are together referred to as antiresorptive agent-related ONJ (ARONJ). The pathogenesis of ARONJ still remains unknown. It is forecasted that there will be an increased incidence of patients with osteoporotic fractures and an increased number of prescriptions for antiresorptive agents in Asia in the future. However, prescriptions for antiresorptives for osteoporosis may be restricted in the Asian population as the occurrence of ARONJ may be higher as compared with those in other countries. In this review, we focused on the following topics as it pertains to the Asian osteoporotic population: the oral condition specific for osteoporosis patients; definition, staging, prevalence and incidence of ARONJ; imaging modalities for ARONJ; specific risk factors for ARONJ; prevention strategies for ARONJ, and; cooperation between physicians and dentists in the prevention of ARONJ. Ideally, the Asian Federation of Osteoporosis Societies would cooperate with one another and find more population-specific evidence for the prevention of ARONJ.

Association between number of teeth present and mandibular cortical erosion in Japanese men and women aged 40 years and older: A cross-sectional study

Mandibular cortical erosion detected on dental panoramic radiographs is associated with increased risk of osteoporosis in older adults. Additionally, many reports have demonstrated an association between decreased number of teeth present and osteoporosis. However, whether mandibular cortical erosion is associated with a decreased number of teeth remains unclear. The purpose of this study, therefore, was to clarify the association between mandibular cortical erosion and number of teeth present in Japanese men and women aged 40 years and older. Among patients who visited our university hospital and underwent dental panoramic radiography for the diagnosis of dental diseases, 839 patients (293 men and 546 women) aged 40–89 years (mean [SD], 63.7 [10.6] years) participated in this study. Multiple regression analysis revealed that mildly to moderately eroded cortex (p = 0.007) and severe eroded cortex (p < 0.001) were significantly associated with a decreased number of teeth present. Analysis of covariance adjusted for covariates revealed a significant association between mandibular cortical erosion category and number of teeth present (p < 0.001). Subjects with a severely eroded cortex had significantly fewer teeth present than those with a normal cortex (mean [SE], 20.7 [0.5] vs. 23.4 [0.3], p < 0.001) or mildly to moderately eroded cortex (22.2 [0.4], p = 0.04). Subjects with a mildly to moderately eroded cortex had significantly fewer teeth present than those with a normal cortex (p = 0.033). Our results suggest the significant association between mandibular cortical erosion and number of teeth present in Japanese men and women aged 40 years and older.

Delayed wound healing after tooth extraction and self-reported kyphosis in Japanese men and women

It is unclear whether osteoporosis itself is a main risk factor for delayed wound healing after tooth extraction in humans. In this study, we evaluated the association between experience of delayed wound healing after last tooth extraction and self-reported kyphosis, with the possibility of having vertebral fractures, in Japanese patients. Among the 1,504 patients who responded to the structured questionnaire survey, 518 patients (134 men and 384 women) aged 55-97 years finally participated in this study. Patients who self-reported mild-moderate kyphosis were more likely to have problematic delayed wound healing after last tooth extraction than those who reported severe kyphosis (odds ratio [OR] 4.98; 95% confidence interval [CI], 1.86-13.38 and OR 2.30; 95% CI, 0.52-10.22, respectively) (p for trend = 0.005). Japanese patients with vertebral fractures may have a higher risk of having problematic delayed wound healing after tooth extraction.