Central hypothyroidism is common in patients
with hypopituitarism
(March 2002)
The background of
the study. The clinical manifestations, hormonal deficiencies,
and causes of hypopituitarism are diverse, and little is known about
its frequency in the general population.
How the study was done. The number
of patients with hypopituitarism who were 18 years and older in
the registry of patients at the General Hospital of Vigo, in northwestern
Spain, was determined from 1992 to 1999. Most, if not all, patients
with pituitary disease in the region are referred to this hospital.
There were 137,465 and 151,587 adults living in the area in 1992
and 1999, respectively. Pituitary hormone secretion was assessed
by standard methods, and the diagnosis of hypopituitarism was based
on the presence of a deficiency of one or more pituitary hormones.
The results of the study. In 1992
there were 40 patients with hypopituitarism in the registry (29
per 100,000 people). In 1999 there were 69 patients (46 per 100,000
people). From 1993 to 1999 there were 4 to 9 new cases per year;
the mean annual incidence rate was 4.2 per 100,000 people per year.
The most common causes of hypopituitarism in both 1992 and 1999
were hormone-secreting pituitary tumors, nonsecreting pituitary
tumors, and hypopituitarism of unknown cause.
Among the 69 patients in 1999 the proportions with 1, 2, 3, 4,
5, and 6 hormonal deficiencies were, respectively, 21 percent, 15
percent, 23 percent, 19 percent, 15 percent, and 7 percent. The
most frequent deficiency was that of gonadotropins (87 percent),
followed by thyrotropin (TSH; 64 percent), corticotropin (62 percent),
and growth hormone (61 percent). The frequency and types of deficiency
were similar in the patients with tumors and those with other disorders.
The conclusions of the study. In
this region of Spain, the annual incidence of hypopituitarism remained
constant for 7 years. The majority of patients had a pituitary tumor,
and TSH deficiency-and therefore hypothyroidism-was common.
The original article. Regal M, Paramo
C, Sierra JM, Garcia-Mayor RV. Prevalence and incidence of hypopituitarism
in an adult Caucasian population in northwestern Spain. Clin Endocrinol
2001;55:735-40.
|
