Effect of inhaled corticosteroids on bones and growth

Inhaled corticosteroids are recognized as the most effective anti-inflammatory therapy in patients with asthma and their early introduction is recommended by national and international guidelines. Concerns hare been raised about potential adverse effects of inhaled corticosteroids on bones and growth, as these appear to be more important clinically than effects on the hypothalamic-pituitary-adrenal axis, which are more commonly measured. This review examines the effects of inhaled corticosteroids on biochemical bone markers, bone density and growth in adults and children with asthma, in view of the recent availability of a substantial amount of new clinical trial data. Examination of relevant retrospective and prospective data, involving 11 studies (1,240 patients) on biochemical bone markers and 14 studies (373 patients) on bone density over a wide dose range, have largely indicated no significant or clinically important effect on these measurements in adults or children with asthma. Markers of bone formation and resorption need to be measured concurrently for a reliable assessment of bone turnover to be made. Knemometry, measuring lower leg growth rate, is a sensitive technique for comparing the systemic activity of different inhaled corticosteroids, but does not relate to long-term growth. The majority of approximately 30 studies on inhaled corticosteroids and statural growth in children, over a wide recommended dose range, including a number of recent long-term, prospective studies, demonstrate little or no effect. Children taking above recommended doses of inhaled corticosteroids should have their growth monitored using stadiometry at least every 6 months by trained personnel. Most of the areas reviewed, particularly the relatively new areas of biochemical bone markers and bone density, require further properly controlled, long-term, prospective investigation, although the long-term value of bone markers appears limited. In summary the data as it currently stands, suggests that doses of inhaled corticosteroids up to 1,000 mu g.day(-1) in adults and 400 mu g.day(-1) in children have no significant effect on bones and growth in the large majority of patients with asthma.