Obesity is an emerging condition, with a prevalence of ~20%. Although the simple measurement of BMI is likely a simplistic approach to obesity, BMI is easily calculated, and there are currently no data showing that more sophisticated methods are more useful to guide the endocrine work-up in obesity. An increased BMI leads to a number of hormonal changes. Additionally, concomitant hormonal diseases can be present in obesity and have to be properly diagnosed – which in turn might be more difficult due to alterations caused by body fatness itself. The present European Society of Endocrinology Clinical Guideline on the Endocrine Work-up in Obesity acknowledges the increased prevalence of many endocrine conditions in obesity. It is recommended to test all patients with obesity for thyroid function, given the high prevalence of hypothyroidism in obesity. For hypercortisolism, male hypogonadism and female gonadal dysfunction, hormonal testing is only recommended if case of clinical suspicion of an underlying endocrine disorder. The guideline underlines that weight loss in obesity should be emphasized as key to restoration of hormonal imbalances and that treatment and that the effect of treating endocrine disorders on weight loss is only modest.
R Pasquali, F Casanueva, M Haluzik, L van Hulsteijn, S Ledoux, M P Monteiro, J Salvador, F Santini, H Toplak, and O M Dekkers
L T van Hulsteijn, R Pasquali, F Casanueva, M Haluzik, S Ledoux, M P Monteiro, J Salvador, F Santini, H Toplak, and O M Dekkers
The increasing prevalence of obesity is expected to promote the demand for endocrine testing. To facilitate evidence guided testing, we aimed to assess the prevalence of endocrine disorders in patients with obesity. The review was carried out as part of the Endocrine Work-up for the Obesity Guideline of the European Society of Endocrinology.
Systematic review and meta-analysis of the literature.
A search was performed in MEDLINE, EMBASE, Web of Science and COCHRANE Library for original articles assessing the prevalence of hypothyroidism, hypercortisolism, hypogonadism (males) or hyperandrogenism (females) in patients with obesity. Data were pooled in a random-effects logistic regression model and reported with 95% confidence intervals (95% CI).
Sixty-eight studies were included, concerning a total of 19.996 patients with obesity. The pooled prevalence of overt (newly diagnosed or already treated) and subclinical hypothyroidism was 14.0% (95% CI: 9.7–18.9) and 14.6% (95% CI: 9.2–20.9), respectively. Pooled prevalence of hypercortisolism was 0.9% (95% CI: 0.3–1.6). Pooled prevalence of hypogonadism when measuring total testosterone or free testosterone was 42.8% (95% CI: 37.6–48.0) and 32.7% (95% CI: 23.1–43.0), respectively. Heterogeneity was high for all analyses.
The prevalence of endocrine disorders in patients with obesity is considerable, although the underlying mechanisms are complex. Given the cross-sectional design of the studies included, no formal distinction between endocrine causes and consequences of obesity could be made.