Worldwide variation in hip fracture incidence weakly aligns with genetic divergence between populations

Global burden of hip fracture: The Global Burden of Disease Study

This study is the first to measure global burden of hip fracture in patients aged 55 years and older across 204 countries and territories from 1990 to 2019. Our study further proved that the global burden of hip fracture is still large. Hip fractures among males are perhaps underestimated, and older adults should be given more attention.

PURPOSE

Hip fracture is a tremendous universal public health challenge, but no updated comprehensive and comparable assessment of hip fracture incidence and burden exists for most of the world in older adults.

METHODS

Using data from the Global Burden of Diseases (GBD) 2019, we estimated the number and rates of the incidence, prevalence, and years lived with disability (YLD) of hip fracture across 204 countries and territories in patients aged 55 years and older from 1990 to 2019.

RESULTS

In 2019, the incidence, prevalence, and YLDs rates of hip fracture in patients aged 55 years and older were 681.35 (95% UI 508.36-892.27) per 100000 population, 1191.39 (95% UI 1083.80-1301.52) per 100000 population, and 130.78 (95% UI 92.26-175.30) per 100000 population. During the three decades, the incidence among people aged below 60 years showed a downward trend, whereas it showed a rapid upward trend among older adults. All the numbers and rates of hip fractures among females were higher than those among males and increased with age, with the highest number and rate in the highest age group. Notably, the male to female ratio of the incidence for people aged over 55 years increased from 0.577 in 1990 to 0.612 in 2019. Falls were the leading cause among both sexes and in all age groups.

CONCLUSIONS

The incidence and the number of hip fractures among patients aged 55 years and older increased over the past three decades, indicating that the global burden of hip fracture is still large. Hip fractures among males are perhaps underestimated, and older adults should be given more attention.

Effects of the energy balance transition on bone mass and strength

Chronic positive energy balance has surged among societies worldwide due to increasing dietary energy intake and decreasing physical activity, a phenomenon called the energy balance transition. Here, we investigate the effects of this transition on bone mass and strength. We focus on the Indigenous peoples of New Mexico in the United States, a rare case of a group for which data can be compared between individuals living before and after the start of the transition. We show that since the transition began, bone strength in the leg has markedly decreased, even though bone mass has apparently increased. Decreased bone strength, coupled with a high prevalence of obesity, has resulted in many people today having weaker bones that must sustain excessively heavy loads, potentially heightening their risk of a bone fracture. These findings may provide insight into more widespread upward trends in bone fragility and fracture risk among societies undergoing the energy balance transition.

Incidence, morbidity and mortality of hip fractures over a period of 20 years in a health area of Southern Spain

OBJECTIVE

To evaluate the incidence of osteoporotic hip fracture in the Macarena Health Area (Seville).

SETTING AND PARTICIPANTS

This was a prospective observational study that collected all osteoporotic hip fractures that occurred between March 2013 and February 2014 at the Clinical Unit of Traumatology and Orthopaedics. All cases collected during the first 6 months of the study were followed for 1 year after the occurrence of the event.

OUTCOME MEASURES

We evaluated the incidence of osteoporotic hip fractures in the Macarena Health Area (Seville) from 1 March 2013 to 28 February 2014, and we compared the incidence with that in 2 previous studies carried out with the same methodology in 1994 and 2006. Furthermore, we calculated the morbidity and degree of disability 1 year after the fracture occurred and determined mortality and the associated factors.

RESULTS

The overall incidence was 228 per 100 000 individuals/year (95% CI 204.5 to 251.6), and the incidence was higher in women than in men. In women, the incidence rate decreased in all age groups over time, while in men, the incidence rate increased. The mortality rate 1 year after the episode was 27.2%. The factors associated with overall mortality were a body mass index below 25 kg/m², renal failure and low plasma proteins.

CONCLUSIONS

Our results show a high incidence of osteoporotic hip fracture that is increasing in men, and in men it is associated with a higher mortality than in women. There is room to improve the modifiable factors associated with mortality and the available rehabilitation interventions to reduce the disability associated with these fractures.

Ethnic differences in risk of hip fracture in Norway: a NOREPOS study

Hip fracture is a major public health problem, and the incidence rates vary considerably between countries. Ethnic differences in bone mineral density have been identified as a factor to explain some of the geographical differences in rates of hip fracture. In this Norwegian register-based study, we found that all immigrant groups experienced lower risk of hip fracture than individuals born in Norway.

INTRODUCTION

Norway is among the countries with the highest incidence rates. The aim of this study was to investigate differences in risk of hip fracture between ethnic groups living in Norway.

METHODS

We linked individuals in the Norwegian Population and Housing Census conducted in 2001 and a database consisting of all hip fractures in Norway in the period 2001-2013. Residents (n = 1,392,949) between 50 and 89 years and born in nine different geographical regions of the world were examined, and we computed age-standardized incidence rates for the different geographic regions-denoted ethnic groups in the paper. Gender-stratified Cox regression analysis, adjusted for age, was used to model risk of hip fracture as a function of region of birth.

RESULTS

Age-standardized incidence rates of hip fracture varied considerably between regions of birth living in Norway, in both genders. All immigrant groups had lower risk of hip fracture compared to the Norwegian-born population. Immigrants from Central and Southeast Asia had the lowest risk of hip fracture when compared to individuals born in Norway (HR = 0.2, 95% CI 0.1-0.3 and HR =0.2, 95% CI 0.2-0.4 in men and women, respectively).

CONCLUSION

Lower risk of hip fracture was found in all immigrant groups compared to the Norwegian-born majority population.

Secular decline in limb bone strength among South African Africans during the 19th and 20th centuries

OBJECTIVES

South African Africans have been reported to have experienced negative or null secular trends in stature and other measures of skeletal structure across the 19th and 20th centuries, presumably due to poor living conditions during a time of intensifying racial discrimination. Here, we investigate whether any secular trend is apparent in limb bone strength during the same period.

MATERIALS AND METHODS

Cadaver-derived skeletons (n = 221) were analyzed from female and male South African Africans who were born between 1839 and 1970, lived in and around Johannesburg, and died between 1925 and 1991 when they were 17-90 years of age. For each skeleton, a humerus and femur were scanned using computed tomography, and mid-diaphyseal cross-sectional geometric properties were calculated and scaled according to body size.

RESULTS

In general linear mixed models accounting for sex, age at death, and skeletal element, year of birth was a significant (p < .05) negative predictor of size-standardized mid-diaphyseal cortical area (a proxy for resistance to axial loading) and polar moment of area (a proxy for resistance to bending and torsion), indicating a temporal trend toward diminishing limb bone strength. No significant interactions were detected between year of birth and age at death, suggesting that the decline in limb bone strength was mainly due to changes in skeletal maturation rather than severity of age-related bone loss.

DISCUSSION

Limb bone strength is thus potentially another feature of the skeletal biology of South African Africans that was compromised by poor living conditions during the 19th and 20th centuries.

Biomechanics of Osteoporotic Fracture Fixation

PURPOSE OF REVIEW

Fractures of osteoporotic bone in elderly individuals need special attention. This manuscript reviews the current strategies to provide sufficient fracture fixation stability with a particular focus on fractures that frequently occur in elderly individuals with osteoporosis and require full load-bearing capacity, i.e., pelvis, hip, ankle, and peri-implant fractures.

RECENT FINDINGS

Elderly individuals benefit immensely from immediate mobilization after fracture and thus require stable fracture fixation that allows immediate post-operative weight-bearing. However, osteoporotic bone has decreased holding capacity for metallic implants and is thus associated with a considerable fracture fixation failure rate both short term and long term. Modern implant technologies with dedicated modifications provide sufficient mechanical stability to allow immediate weight-bearing for elderly individuals. Depending on fracture location and fracture severity, various options are available to reinforce or augment standard fracture fixation systems. Correct application of the basic principles of fracture fixation and the use of modern implant technologies enables mechanically stable fracture fixation that allows early weight-bearing and results in timely fracture healing even in patients with osteoporosis.

Computed tomography shows high fracture prevalence among physically active forager-horticulturalists with high fertility

Modern humans have more fragile skeletons than other hominins, which may result from physical inactivity. Here, we test whether reproductive effort also compromises bone strength, by measuring using computed tomography thoracic vertebral bone mineral density (BMD) and fracture prevalence among physically active Tsimane forager-horticulturalists. Earlier onset of reproduction and shorter interbirth intervals are associated with reduced BMD for women. Tsimane BMD is lower versus Americans, but only for women, contrary to simple predictions relying on inactivity to explain skeletal fragility. Minimal BMD differences exist between Tsimane and American men, suggesting that systemic factors other than fertility (e.g. diet) do not easily explain Tsimane women's lower BMD. Tsimane fracture prevalence is also higher versus Americans. Lower BMD increases Tsimane fracture risk, but only for women, suggesting a role of weak bone in women's fracture etiology. Our results highlight the role of sex-specific mechanisms underlying skeletal fragility that operate long before menopause.