Hip fracture is a major public health problem. Earlier studies projected that the total number of hip fracture will increase dramatically by 2050, and most of the hip fracture will occur in Asia. To date, only a few studies provided the updated projection, and none of them focused on the hip fracture projection in Asia. Thus, it is essential to provide the most up to date prediction of hip fracture in Asia, and to evaluate the total direct medical cost of hip fracture in Asia. We provide the updated projection of hip fracture in 9 Asian Federation of Osteoporosis Societies members using the most updated incidence rate and projected population size. We show that the number of hip fracture will increase from 1,124,060 in 2018 to 2,563,488 in 2050, a 2.28-fold increase. This increase is mainly due to the changes on the population demographics, especially in China and India, which have the largest population size. The direct cost of hip fracture will increase from 9.5 billion United State dollar (USD) in 2018 to 15 billion USD in 2050, resulting a 1.59-fold increase. A 2%-3% decrease in incidence rate of hip fracture annually is required to keep the total number of hip fracture constant over time. The results show that hip fracture remains a key public health issue in Asia, despite the available of better diagnosis, treatment, and prevention of fracture over the recent years. Healthcare policy in Asia should be aimed to reduce the burden of hip fracture.

Sarcopenia is an important factor of functional impairment related to aging. This study is conducted to investigate the prevalence of sarcopenia and sarcopenic obesity in Korean population. Representative Korean men (4,486) and women (5,999) aged 20 years or older were analyzed from the Fourth Korean National Health and Nutritional Examination Surveys. Sarcopenia was classified into Class I defined relative skeletal muscle mass loss within 1–2 SD of the gender-specific mean for healthy young adults and Class II below 2 SD. Relative skeletal muscle mass was represented by the appendicular skeletal muscle mass adjusted by height and body weight. Sarcopenic obesity was considered present in Class II sarcopenic participants whose waist circumference was more than or equal to 90 cm for men and more than or equal to 85 cm for women, respectively. The prevalence of Class II sarcopenia in the Korean elderly population was 12.4% for men and 0.1% for women by height-adjusted definition and 9.7% for men and 11.8% for women by weight-adjusted definition. The prevalence of sarcopenic obesity was 7.6% for men and 9.1% for women by weight-adjusted definition but nearly zero for men and women by height-adjusted definition. The prevalence of sarcopenia increased with age for men but for women only when applied with weight-adjusted definition. The prevalence of sarcopenia and sarcopenic obesity differs by gender and definition criteria. The height-adjusted definition may tend to underestimate the prevalence of sarcopenia and sarcopenic obesity, especially in women.

Objective: this study examined the association of physical activity with sarcopenia and sarcopenic obesity among the community-dwelling Korean elderly. Methods: subjects consisted of 2,264 aged 65 years or older in the 2008–09 Korea National Health and Nutrition Examination Survey. Sarcopenia was defined as 2 SD below the mean of the appendicular skeletal muscle/weight for healthy young adults. Obesity was defined as waist circumference ≥90 cm for men and ≥85 cm for women. Levels of physical activity were classified using the metabolic equivalent task method. Results: the prevalence of sarcopenia was 12.1% in men and 11.9% in women. Among those with sarcopenia, obesity was prevalent in 68.3% of men and 65.0% of women. Adjusting for all covariates, compared with those with low physical activity, men who engaged in moderate and high activity were 38% and 74%, respectively, less likely to have sarcopenia (P_trend < 0.001). In women, the relationship between physical activity and sarcopenia was not significant. For sarcopenic obesity, men participating in moderate [odds ratio (OR) = 0.47; 95% confidence interval (CI) 0.26–0.87] and high (OR = 0.27; 95% CI: 0.12–0.60) physical activity, compared with low activity, had significantly lower risk (P_trend = 0.001). In women, high physical activity was associated with a lower risk of sarcopenic obesity (OR = 0.43; 95% CI: 0.22–0.86). Conclusion: physical activity is associated with a reduced risk of sarcopenia and sarcopenic obesity in older Korean adults. There were gender differences in the relationship, with stronger associations observed in men than in women.

Lee S, et al. J Korean Med Sci. 2006 Aug;21(4):695-700. https://doi.org/10.3346/jkms.2006.21.4.695

It is well established that insulin-like growth factor (IGF)-I is critical for the regulation of peak bone mineral density (BMD) and bone width. However, the role of systemic vs. local IGF-I is not well understood. To determine the role local IGF-I plays in regulating BMD and bone width, we crossed IGF-I flox/flox mice with procollagen, typeIIαI-Cre mice to generate conditional mutants in which chondrocyte-derived IGF-I was disrupted. Bone parameters were measured by dual X-ray absorptiometry at 2, 4, 8, and 12 wk of age and peripheral quantitative computed tomography at 12 wk of age. Body length, areal BMD, and bone mineral content (BMC) were reduced (P < 0.05) between 4 and 12 wk in the conditional mutant mice. Bone width was reduced 7% in the vertebrae and femur (P < 0.05) of conditional mutant mice at 12 wk. Gains in body length and total body BMC and BMD were reduced by 27, 22, and 18%, respectively (P < 0.05) in conditional mutant mice between 2 and 4 wk of age. Expression of parathyroid hormone related protein, parathyroid hormone receptor, distal-less homeobox (Dlx)-5, SRY-box containing gene-9, and IGF binding protein (IGFBP)-5 were reduced 27, 36, 45, 33, and 45%, respectively, in the conditional mutant cartilage (P < 0.05); however, no changes in Indian hedgehog, Dlx-3, growth hormone receptor, IGF-I receptor, and IGFBP-3 expression were observed (P ≥ 0.20). In conclusion, IGF-I from cells expressing procollagen type IIαI regulates bone accretion that occurs during postnatal growth period.