Introduction: Among older populations, osteoarthritis (OA) is one of the most common chronic joint disorders and is a leading cause of disability, while osteoporosis is the most common metabolic bone disease, conferring fragility and significant risk of fracture. The relationship between OA and osteoporosis remains controversial. Although earlier studies reported an inverse association between the two diseases, more recent literature found a complex relationship mediated by various factors. Objective: The investigators sought to determine the association of osteoporosis with radiologic grading of the hip among older Filipino patients with suspected hip osteoarthritis. Methodology: A cross-sectional analytical study was conducted involving 256 patients with suspected hip OA who underwent radiography of the hips and central dual energy x-ray absorptiometry (DXA). Radiographs of the hips were evaluated by a radiologist using the Kellgren-Lawrence (KL) grading scale, while central DXA images were processed and evaluated by a nuclear medicine physician using the World Health Organization criteria for the diagnosis of osteoporosis and the 2019 International Society for Clinical Densitometry guidelines. The primary outcome measures were the prevalence of osteoporosis in patients with suspected hip OA, and the association of osteoporosis with radiologic KL grading of the hips. The secondary outcome measure was the association of osteoporosis with sex and BMI. Results: The study found that osteoporosis was present in 136 (53.1%) of the 256 patients who all presented with radiologic evidence of hip OA. There was a positive association between the presence of osteoporosis and the radiologic grade of hip OA (p-value: 0.006 on the right hip and 0.036 on the left). Osteoporosis was more prevalent in women compared to men (p-value: 0.031). Likewise, osteoporosis had a direct relationship with BMI (p-value: <0.001). Conclusion Osteoporosis was prevalent in a significant proportion of older Filipino patients with clinical and radiologic evidence of hip OA, particularly among women, and was positively associated with increasing severity of OA. The study suggests that obesity may not necessarily protect against osteoporosis in this population, possibly relating to increased adiposity and decreased lean muscle mass.
Osteoporosis ; Osteoarthritis ; Osteoarthritis, Hip ; Absorptiometry, Photon