[Acromegaly in elderly people]

Treatment of elderly acromegalics

We assessed the incidence of elderly patients in Japanese acromegalics and the characteristics of their clinical presentation. We also evaluated the safety and efficacy of transsphenoidal surgery (TSS) in this patient group. During the 28-year period from 1980 to 2007 we treated 290 patients with acromegaly at our hospitals. Of these, 9 (3.1%) were elderly, i.e. 70 years old or older. They comprised 0.7% of acromegalics treated during the first- and 4.5% of patients with acromegaly treated during the 2nd 14-year period. Before treatment, all manifested abnormal glucose tolerance; 6 had diabetes mellitus (DM), 6 presented with hypertension, and 2 had cardiovascular disease, malignant neoplasms, or hyperlipidemia. Of the 7 elderly acromegalics who underwent TSS none manifested surgical morbidity or new pituitary hormone deficiencies. Postoperatively, the nadir growth hormone (GH) level at the oral glucose tolerance test (OGTT) was under 1.0 ng/mL in 5 patients, insulin-like growth factor (IGF-1) levels normalized in 4. Glucose tolerance improved in all operated patients. Only 1 of 6 patients with preoperatively diagnosed DM continued to manifest DM post-treatment, anti-hypertensive drugs could be tapered in 3 of patients with preoperative hypertension. In conclusion, we found that there was a high incidence of abnormal glucose tolerance and hypertension in elderly acromegalics, that surgical treatment was effective and safe in this population, and that it was useful for the control of co-morbidities.

Current diagnosis of acromegaly

Acromegaly is a rare and chronic condition that is characterized by sustained unregulated hypersecretion of growth hormone (GH). More than 99% of the cases of acromegaly are due to a pathologic proliferation of pituitary somatotrophs presenting in the form of a pituitary adenoma. The excessive amounts of GH and its target hormone, insulin like growth factor-1 (IGF-1) cause metabolic changes and tissue enlargement that, collectively, lead to significant morbidity and a two to threefold increase in mortality. Thus, early diagnosis has proved to be crucial to improve survival and quality of life in this condition. The development of radioimmunoassay (RIA) in the 1960s provided clinicians with a biochemical tool to diagnose acromegaly. Many limitations were inherent to this methodology which necessitated the development of more sensitive tools, such as immunoradiometric (IRMA) or immunoluminometric (ILMA) assays for GH and IGF-1 measurements. These newer assays have not come without imperfections. The reference ranges to describe normalcy of the somatotropic axis and the biochemical criteria of "cure" of acromegaly are areas of great debate. Nevertheless, the current international consensus agrees that the diagnosis of acromegaly should be based on both clinical presentation and biochemical data.

A retrospective analysis on biochemical parameters, cardiovascular risk and cardiomyopathy in elderly acromegalic patients

This analytical, observational, retrospective, case-control study was designed to describe clinical presentation, biochemical disease severity, presence, and severity of metabolic and cardiovascular complications in patients diagnosed as having acromegaly at 60 yr or older (no.=57) as compared to sex- and age-matched healthy controls. Patients and controls underwent a complete endocrine, metabolic, and cardiovascular check-up. The age at diagnosis was equally distributed between 60 to 75 yr while only a minority of the patients (5.3%) was diagnosed after 75 yr. Median GH and IGF-I levels were 15 microg/l and 557 microg/l. The prevalence of microadenomas, enclosed macroadenomas, and extrasellar/invasive macroadenomas was 30%, 49%, and 21%, respectively. All patients had joint complaints and goiter (euthyroid in 65% and pre-toxic/toxic in 35%), 82% had hypertension, 58% diabetes and 54% had both. As compared to controls, a higher number of patients were receiving treatment with anti-arrhythmiacs (p=0.033), anti-aggregants (p=0.013), levothyroxine (p=0.015), and metformin (p=0.022). Nevertheless, the patients had higher systolic and diastolic blood pressure, heart rate, left ventricular mass index, lipids, glucose and insulin levels as well as percent function of beta cells than controls. In conclusion, the high prevalence of systemic complications makes elderly acromegalics more susceptible than controls to cardiovascular events. We suggest that an accurate clinical check-up and, possibly, a more aggressive treatment of hypertension and diabetes are required in elderly acromegalics.

Defining normalcy of the somatotropic axis: an attainable goal?

The diagnoses of acromegaly and dwarfism require biochemical confirmation of abnormal GH and IGF-1 concentrations. The same parameters are used for therapeutic decisions, i.e. initiation or termination of particular treatments. Therefore, reliable and epidemiologically and statistically proven criteria of normalcy for GH and IGF-1 are required for these tasks to be accomplished. Despite major progress in all these areas, the definition of what constitutes "normalcy" of the somatotropic axis is still lacking. Using an example of acromegaly, we discuss the contradictions and the uncertainties of the biochemical diagnosis of this disease.