Lionel Messi is perhaps the world’s most celebrated soccer player. Despite standing only 5’6”, the Argentinian striker is strong, fast, and impossibly skilled. However, as a child, doctors predicted he wouldn’t grow any taller than 4’7”. Diagnosed at age 11 with a growth-hormone deficiency, his parents arranged for him to receive prohibitively expensive human growth hormone (HGH) treatments, which were financed largely by FC Barcelona, still his employer 13 years later.
HGH helped Messi overcome a hormone deficiency. However, when administered before and during puberty, HGH can also increase the permanent height of children with normal hormone levels. Although some health concerns have been raised, it appears that the risks of treating healthy children with HGH are low. In a society where height is explicitly prized, and empirical evidence indicates all-but conclusively that a couple extra inches (especially for men) can help life proceed more swimmingly, what’s holding us back from a child-doping arms race?
The main legal bulwark is the line the FDA draws for marketers. Eli Lilly markets its version of recombinant human growth hormone, or rHGH (Humatrope®), not only for treatment of hormone deficiencies but also for treatment of “idiopathic short stature.” The definition of idiopathic short stature that Eli Lilly proposed, and the FDA accepted in 2003, is: children at least 2.25 standard deviations below the mean height for their age and sex. That corresponds to the shortest 1.2% of children. To many observers, this definition seems eminently reasonable given the limited contraindications. The lay-public’s tendency to equate HGH with steroids is probably alarmist.
However, it is worth reflecting on the conceptual arbitrariness of the definition. The FDA defended itself by noting that associations such as the American Association of Clinical Endocrinologists and the Growth Hormone Research Society have defined short stature as two standard deviations below the mean, which would encompass the lowest 2.3% rather than the lowest 1.2% of the spectrum. However, those professional associations are not necessarily impartial experts. Furthermore, independent researchers who have employed the more inclusive definition have generally not done so with HGH prescription in mind; their definitions are therefore scant authority. Although the FDA weighs new drug indications using a reasonable three-pronged analysis based upon benefits, effectiveness, and safety, the conceptual difficulty of the FDA’s line-drawing exercise is apparent in its deliberation. Since 2003, HGH usage has spiked not only among children with idiopathic short stature but throughout the population. A difference of a few tenths of a standard deviation in the FDA’s approval profoundly affects the lives of millions of people—and arguably, the medical norms of the entire society.