September 14, 2009
Crunching the numbers on hormone-related disorders in U.S.
A dogged review of the medical literature has produced what is believed to be the nation’s first comprehensive estimate of the extent of dozens of endocrine disorders in the United States.
Unsurprisingly, say the Johns Hopkins researchers who gathered the data, obesity and related conditions including metabolic syndrome and diabetes were the most common disorders and had the highest estimated rate of new cases per year–what experts call “prevalence” and “incidence,” respectively. However, the review also shed light on the significant impact that several other conditions have at the population level, such as osteoporosis. Surprisingly, the researchers say, their review showed that this bone-thinning condition appears to affect men and women nearly equally, with about 7 percent prevalence for both sexes. Health professionals have long assumed that osteoporosis occurs primarily in women after menopause, as a consequence of estrogen hormone loss.
“Endocrinologists confidently talk about how common or uncommon certain hormone-related conditions are, but we were lacking the hard numbers. Now we have compiled real data based on U.S.-based clinical studies,” said Sherita Hill Golden, associate professor in the Division of Endocrinology and Metabolism at the Johns Hopkins University School of Medicine.
Golden said that many endocrine disorders appear to be on the rise in the United States and around the world but that scientists have never amassed hard numbers in a unified source of prevalence or risk as they have for such medical conditions as cancer and heart disease.
“Without such information, it’s hard to get public health decision makers to focus on all endocrine disorders, develop preventive strategies and allocate the right level of funding for research and treatment,” Golden said.
To address the lack of information, Golden and her colleagues searched medical article databases for prevalence and incidence data for 54 endocrine disorders with both clinical and public health significance, identifying 2,268 studies. They concentrated on the most recent (since 1998) 70 articles that had the most rigorous data on the general population, as opposed to studies involving small groups of patients from specialty clinics that see higher numbers of endocrine disorders. Reporting in the June Journal of Clinical Endocrinology and Metabolism, Golden and her colleagues found, as expected, that obesity-related diseases such as diabetes were the most common endocrine disorders in the United States, with 25 percent to 28 percent of the population being clinically obese and 10 percent having type-2 diabetes. The review suggests that more than a third of the population has metabolic syndrome, a collection of obesity-related conditions that includes blood fat disorders, insulin resistance and the presence of inflammatory proteins that increase the risk for heart disease and stroke.
The review also found that type-1 diabetes and tumors of the pituitary gland are among the least common endocrine disorders, affecting less than 1 percent of the population. Golden noted that there is a general lack of multiethnic, multiracial studies, research needed to determine variable risk in specific populations.
The study was funded by a grant from the Endocrine Society.
Other researchers who participated in this study are Karen A. Robinson, Ian Saldanha, Blaire Anton and Paul W. Ladenson, all of Johns Hopkins.