Most common causes of 2ry osteoporosis are coeliac disease and primary hyperparathyroidism; myeloma is also a cause. Therefore, investigations include FBC, PV, U&Es, coeliac screen, calcium profile, and immunuglobulins, possibly plus BJP. What the pick-up rate and cost-effectiveness of these is isn’t clear from the article.
Alendronate is now the first-line treatment in usual circumstances. Risedronate is equally effective. Ibandronate has less evidence of efficacy. GI side-effects are well known and osteonecrosis of the jaw hit the headlines a few years back, but AF and uveitis are other rare but serious SEs to note. Less uncommon are renal impairment and hypocalcaemia. Oral bisphosphonates should be given for five years, followed by repeat DEXA scan, followed by further five years treatment if still osteoporotic as evidence for reduced risk of vertebral fractures with second 5 years. For zolendronate, three years of therapy seems to be enough.
Strontium ranelate is as effective as alendronate as preventing vertebral fractures (50% reduction) but less so at non-vertebral fracture prevention (16% reduction compared to alendronate which gives 40% reduction for hip fractures and 25% for others). It can cause diarrhoea, rashes, and increased DVT risk. It is not clear whether the effects on bone persist after stopping treatment and therefore treatment should be continued indefinitely.
Denusomab is as effective as alendronate in preventing vertebral fractures and more so in preventing spinal fractures. Effect is known to wear off after stopping treatment so it should be given indefinitely.
Teriparatide is expensive and requires daily subcut injection for two years, but works better than bisphosphonates for both vertebral & non-vertebral fracture prevention. Because of the cost it is only recommended for patients who have T scores < -4.
Raloxifene reduces risk of vertebral fractures and thus is sometimes useful in younger (postmenopausal) women with low spine BMD. Effects wear off rapidly when stopped (which is also true for HRT).
(Prescriber, 19th Nov 2012 )