Opening Vignette Mr Loh is a 69-year-old retired engineer with a history of hypertension and newly diagnosed high-grade, locally advanced, non-metastatic prostate cancer. He is scheduled to start on androgen deprivation therapy. He presents to your clinic to discuss screening for bone health, as he has heard that the medication used for his prostate cancer may increase the risk of osteoporotic fractures.WHAT IS MALE OSTEOPOROSIS? Osteoporosis is a condition of decreased bone mass leading to an increased risk of fragility fractures. It has been traditionally viewed as a disease of postmenopausal women. However, research shows that this disease also causes a substantial health burden in men. It is estimated that after the age of 50 years, one in five men will experience an osteoporotic fracture in their lifetime.1 Globally, 39% of osteoporotic fractures occur in men.2 Mortality is higher in males who suffer osteoporotic fractures than in females. Worldwide, men face a 1.3–2-fold higher mortality risk after a hip or vertebral fracture, a difference that may be due to increased infection rates and multimorbidity in men.3,4 Locally, a cohort study conducted at the Singapore General Hospital in 2007 showed a calculated 1-year mortality rate of 32.0% for males following a hip fracture, compared to 24.4% for females.5 WHAT CAUSES MALE OSTEOPOROSIS? Low bone mass in men can generally be attributed to one or more of the following factors: (a) suboptimal peak bone mass acquisition (80% of peak bone mass is genetically determined; environmental factors such as poor nutrition and decreased physical activity can contribute to suboptimal peak bone mass6); (b) ongoing bone loss (contributed by secondary causes of osteoporosis, e.g. heavy smoking, excess alcohol (ETOH) intake, long-term glucocorticoid exposure); or (c) reduced bone formation (e.g. androgen deficiency or ageing). Women experience a period of rapid decline in bone mineral density (BMD) after menopause due to the loss of ovarian oestrogens. In men, however, age-related gonadal decline is much more gradual. HOW RELEVANT IS THIS TO MY PRACTICE? Primary care physicians are ideally equipped to identify male patients at risk of osteoporosis, due to their role as the first point of contact in healthcare, coupled with the close relationships and long-term continuity of care with their patients.7 This allows for personalised care and better identification of risk factors over time. With the introduction of Healthier SG,8 the increased focus on preventive care will empower primary care physicians to educate men about lifestyle changes that can enhance bone health, such as smoking cessation, diet and exercise. By coordinating care with specialists, when necessary, primary care physicians can ensure a comprehensive approach to osteoporosis management. WHAT CAN I DO IN MY PRACTICE? Primary care physicians should be on the lookout for osteoporosis in all male patients, starting from age 65, or younger if significant risk factors are present.9 Several guidelines have also proposed performing a clinical risk assessment for all males starting from age 50 to guide the need for further BMD testing.10,11 Physicians should consider performing a dual-energy X-ray absorptiometry (DXA) BMD test for males aged ≥65 years if they have risk factors for low bone mass. They should also consider the test for those aged 70 years with osteoporosis can be managed in primary care. Non-pharmacological management focuses on addressing lifestyle factors that lead to bone loss, such as smoking, excessive alcohol consumption, physical inactivity and inadequate nutrition. Pharmacological treatment options should be evaluated based on fracture risk. For patients at very high fracture risk, physicians should discuss the possibility of commencing anabolic or parenteral treatment as a first-line treatment. Patients keen to commence parenteral treatment may be referred to a specialist for further management. Male patients with osteoporosis who are managed in primary care can be treated with oral bisphosphonates. Closing Vignette Further history reveals that Mr Loh has a 40 pack-year smoking history, no prior fractures and a maternal history of hip fracture at age 80. Physical examination shows dental caries. His BMI is in the healthy range, and his fall risk is low. Given his increased risk of osteoporosis, you arrange a DXA scan and baseline bone health investigations. Mr Loh’s DXA results show a femoral neck T-score of –3.3 and a Z-score of –1.9, and his 25-OH vitamin D is low at 13 ng/mL. Corrected calcium level is 2.2 mmol/L, and a recent bone scan excluded bony metastases. You determine that his osteoporosis is attributed mainly to smoking and vitamin D deficiency. You counsel smoking cessation, refer him for dental review in preparation for antiresorptive therapy, and arrange for dietitian input to optimise calcium, vitamin D and protein intake, together with oral calcium and vitamin D supplementation. You assess Mr Loh to be at high risk of fracture and explain that androgen deprivation therapy may further reduce bone mineral density. After discussing the risks and benefits of treatment, you refer him to an endocrinologist for consideration of parenteral therapy.Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest. SMC CATEGORY 3B CME PROGRAMME Online Quiz: https://www.sma.org.sg/cme-programme Deadline for submission: 6 pm, 28 March 2026
Poh et al. (Sun,) studied this question.