Somatostatin analogues improve acromegaly but affect glucose metabolism
Treatment with somatostatin analogues (SSAs) improves disease control in patients with acromegaly but reduces insulin levels, increases after-load glucose and increases glycated haemoglobin (HbA1c) levels without affecting fasting plasma glucose (FPG), suggests a recent study.
A meta-analysis of prospective interventional trials treating acromegaly with SSAs was conducted. All studies reporting glycometabolic outcomes before and after SSAs with a minimum 6-month follow-up were included. A total of 47 studies involving 1,297 patients (631 females) met the inclusion criteria.
The meta-analysis sought to answer the following questions: 1) Do SSAs affect FPG, fasting plasma insulin HbA1c, glucose load (glucose levels after a 2-hour oral glucose tolerance test), homeostatic model assessment of insulin resistance (HOMA-I), HOMA of pancreatic β-cell function (HOMA-β), triglycerides, weight or body mass index? 2) Do lanreotide and octreotide affect metabolism differently? 3) Does their effect depend on disease control?
SSAs were effective in reducing fasting plasma insulin (effect size [ES], –6.67; mU/L; 95 percent CI, –8.38 to –4.95 mU/L; p<0.001), HOMA-I (ES, –1.57; –2.42 to –0.72; p<0.001), HOMA-β (ES, –47.45; –73.15 to –21.76; p<0.001) and triglycerides (ES, –0.37 mmol/L; –0.47 to –0.27 mmol/L; p<0.001).
On the other hand, SSA treatment led to worse glucose levels after a 2-hour oral glucose tolerance test (ES, 0.59 mmol/L; 0.05–1.13 mmol/L; p=0.032), but not for FPG. In addition, there was a mild but significant increase in HbA1c (ES, 0.12 percent; 0.00–0.25 percent; p=0.044) patients treated with octreotide.
“The findings suggest that clinicians treating acromegaly with SSAs should consider targeting postprandial glucose,” the investigators said.
SSAs are used to effectively control growth hormone secretion in first- and second-line treatment of acromegaly, they noted.