Younger Men with Distal Radius Fractures May Have Hormonal Imbalance

Young men with distal radius fracture are likely to have hormonal imbalances suggests the first study to look at sex hormone levels in younger men experiencing fractures.

The study, published online in Journal of Bone and Mineral Research Plus, found that men with distal radius fractures had higher levels of luteinizing hormone, lower levels of calculated free testosterone and a reduced total estradiol to sex hormone binding globulin ratio.

Sex hormones have an important role in bone health in both men and women. In older men, low estradiol, rather than testosterone, has been found to be associated with low bone mineral density, although incidence of fragility fracture seems to be higher when both estradiol and testosterone are low. However, whether the same association is seen in men aged below 70 years was unknown because little is known about the sex hormone profile of younger men with fracture.

Lead researcher Professor Kristina Åkesson, pro-dean of the faculty of medicine at Lund University, and professor of orthopedics at Skane University Hospital Malmö, Sweden, said: “We are well aware of the importance of sex hormones on reaching peak bone mass and on the skeletal health of older men. However, no one had investigated the sex hormone profiles of younger men with fractures, probably due the assertion that fractures in this age group are caused by high energy trauma like traffic accidents or fall from heights.”

Distal radius fracture is one of the earliest indicators of osteoporosis and a predictor of more severe fragility fractures in the future. For example, men who sustain distal radius fractures have a three fold greater risk of subsequent hip fracture.

So Dr. Åkesson and her team evaluated blood sex hormone levels of 73 men with distal radius fracture who had an average age of 38 years, and compared levels with those of 194 age-matched controls.

The results showed that, compared to controls, men who had sustained a distal radius fracture had significantly lower calculated free testosterone (cFT) (298 vs 329 pmol/l; p=0.008) but not total testosterone. While there was no significant difference between follicle stimulating hormone and sex hormone binding globulin levels, levels of luteinizing hormone was almost 30% higher (5.7 vs 4.5 IU/l; p<0.001) in men who had sustained a distal radius fracture, and they had lower levels of estradiol (80.0 vs 87.1, p=0.098) and a lower estradiol to sex hormone binding globulin ratio.

The researchers calculated that low free testosterone was associated with a 2.3 fold increased odds of having a distal radius fracture while low estradiol increased the odds by 1.7.

Low total testosterone was defined as <10.5 nmol/l, low calculated free testosteroneas <220 pmol/l and low estradiol as <73 pmol/l. Compared with controls, a higher proportion of the men with distal radius fracture had low total testerone (21% vs 11%, p=0.052), low calculated free testosterone (18% vs 8%, p=0.017) and low estradiol (48% vs 35%, p=0.044).

While this is the first study to show that younger men with fracture are at risk of having low levels of sex hormones, the findings also highlight that a fracture in a younger man may be the first sign of an underlying unrecognized illness, said Professor Åkesson.

“That is what the clinician should be aware of in their assessment of a male with fracture. I think that we need to look at fractures just as we do heart attacks; they are often the first sign of treatable conditions or unhealthy lifestyles and we need to find those factors in order to minimize the risk of the next fracture.”

Low levels of sex hormones can be due to congenital conditions and disruptions in the hypothalamic-pituitary-gonadal axis, but can also be related to environmental factors, past infection, injury to the testis, obesity, diabetes, and use of anabolic steroids or other drugs.

“Men are often neglected in screening for osteoporosis and I hope that our study will further highlight the importance of evaluating the men with fractures for underlying conditions; by improving his skeletal health, you also improve his overall health,” Dr. Åkesson said.

“We hope that our study will inspire future studies in men with fracture or low levels of sex hormones to deepen our knowledge on the impact on microstructural changes in the skeleton, bone mineral density and risk of fracture.”

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REFERENCE

Egund L, Isaksson S, McGuigan FE, Giwercman A, Åkesson KE. High Luteinizing Hormone and Lower Levels of Sex Hormones in Younger Men With Distal Radius Fracture. JBMR Plus. 2020 Nov 2;4(11):e10421. doi: 10.1002/jbm4.10421. PMID: 33210067; PMCID: PMC7657392.