Body Habitus Across the Lifespan and Risk of Pituitary Adenoma.

CONTEXT: No studies have examined the association between body habitus and incidence of pituitary adenoma.

OBJECTIVE: To determine if body mass index (BMI), waist circumference, body somatotype, or height are associated with risk of pituitary adenoma.

DESIGN: Pooled analysis of 3 prospective cohort studies.

SETTING: Population-based study.

PARTICIPANTS: Participants of the Nurses' Health Study (NHS), Nurses' Health Study II (NHSII), and the Health Professionals Follow-Up Study (HPFS), totaling 284 946 American health professionals.

EXPOSURES: BMI, waist circumference, body somatotype, and height.

OUTCOME MEASURES: Self-reported incident pituitary adenoma. Multivariable (MV)-adjusted hazard ratios (HRs) of pituitary adenoma were estimated using Cox proportional hazards models.

RESULTS: During 7 350 156 person-years of follow-up, 387 incident pituitary adenomas were reported. Comparing BMI of ≥30 to <25 kg/m2, higher adult BMI was associated with higher risk of pituitary adenoma (MV HR = 1.74; 95% CI, 1.33-2.28), as was higher maximum adult BMI (MV HR = 1.76; 95% CI, 1.34-2.30), higher waist circumference (MV HR = 1.06; 95% CI, 1.04-1.09 per inch), and higher BMI during early adulthood (at age 18 to 21, MV HR = 2.65; 95% CI, 1.56-4.49). Taller adult height was associated with pituitary adenoma (MV HR = 1.05; 95% CI, 1.01-1.09 per inch). Overall findings were similar in women and men, although power was limited in men (n = 62 cases). Sensitivity analyses demonstrated that the association between adult BMI and pituitary adenoma extended to at least 14 years prior to diagnosis and that the results were not affected when analyses were restricted to participants with similar healthcare utilization.

CONCLUSION: Higher BMI and waist circumference, from early adulthood to the time of diagnosis, were associated with higher risk of pituitary adenoma.