Patients 60 and older living with Cushing’s disease have lower body mass index, a measure of body fat, and more muscle wasting than patients younger than 60, a study has found. However, the rates of remission following surgery are similar.
The study, “Cushing’s Disease in Older Patients: Presentation and Outcome,” was published in the journal Clinical Endocrinology.
Cushing’s syndrome is a condition caused by a tumor in the pituitary gland producing excess adrenocorticotropic hormone (ACTH), which causes the adrenals to secrete too much cortisol.
Patients’ symptoms usually weight gain, fat deposition around the waist, stretch marks, muscle wasting, and fatigue, and may develop other conditions as a result of prolonged cortisol exposure.
This leads to a high mortality rate. But studies suggest that the risk of death is higher in older patients, even after they receive surgery for their tumors.
To address this matter, researchers compared the clinical manifestations and outcomes of younger and older patients. Their study included 45 patients 60 and older, and 90 patients younger than 60.
As a control group, investigators examined the clinical records of patients with pituitary tumors, but normal hormone secretion, called nonfunctioning pituitary adenomas (NFPA).
The percentage of women was higher among younger patients (7.2 females for every male) compared to older patients (2.8 females for every male). Patients in the NFPA group had the lowest female-to-male ratio.
Interestingly, older patients seemed to have an increase in their catabolism, which is a part of the metabolism that breaks down nutrient molecules. These patients had a significantly lower body mass index (BMI) and more patients experienced muscle wasting (atrophy), compared to younger patients.
Younger patients, on the other hand, were more likely to gain weight than older patients.
Female hirsutism — a condition characterized by male-pattern hair growth in women — also was more frequent in younger patients.
Older patients had more medical comorbidities, which included hypertension, diabetes, history of cardiovascular disease, and history of deep vein thrombosis, compared to both younger patients and those with NFPA. There also was a trend toward increased occurrence of multiple bone fractures in the older group of patients.
“The effects may be cumulative and likely attributed to hypercortisolism [high cortisol levels] rather than aging alone,” investigators explained.
The rates of complications from surgery were similar in both groups, as were the rates of remission after surgery. However, more younger patients experienced disease relapse — 19.2% versus 2.6%, respectively.
The researchers noted that Cushing’s disease in older patients is less well-understood and may have different features compared to the disease in younger patients, which may make diagnosis more difficult. They call for more studies on this older population of patients.
“Older patients with CD appear to have a distinct phenotype [profile] with a more catabolic picture, including a lower BMI and greater prevalence of muscle wasting. Surgical outcomes are similar without a significant age-related increase in complications,” investigators wrote.
“In summary, our data suggest that the clinical phenotype in older patients with CD may be different from those of younger patients, which may compound the diagnostic difficulties, and merit increased attention from endocrinologists and neurosurgeons. More quantitative prospective studies would be helpful to confirm these findings and define the underlying mechanisms,” they concluded.