Acromegaly is a rare condition where the body makes too much growth hormone. Researchers studied 381 patients with acromegaly and found that more than half (57.5%) had anemia, which means they didn’t have enough healthy red blood cells. Most cases were mild, but the study showed that people with larger tumors, those needing more aggressive treatment, and those with other pituitary gland problems were more likely to develop anemia. Interestingly, doctors couldn’t explain why most of these patients had low red blood cell counts, suggesting there’s something about acromegaly itself that affects blood cell production.

The Quick Take

  • What they studied: How often anemia (low red blood cell counts) happens in people with acromegaly, what types of anemia they develop, and what factors make someone more likely to get it.
  • Who participated: 381 patients with acromegaly being treated at a major medical center. About 120 were women and 98 were men (the rest had incomplete data). All had been diagnosed with acromegaly and were receiving ongoing care.
  • Key finding: More than half of the patients (219 out of 381, or 57.5%) had anemia. Most cases were mild and involved normal-sized red blood cells. Patients with larger tumors, those needing stronger treatments, and those with other pituitary problems were significantly more likely to have anemia.
  • What it means for you: If you have acromegaly, your doctor should regularly check your blood cell counts because anemia is common in this condition. However, this study doesn’t tell us how to prevent or treat acromegaly-related anemia yet—more research is needed. This finding is most relevant to people already diagnosed with acromegaly.

The Research Details

This was a retrospective study, meaning researchers looked back at medical records of patients who had already been treated at a hospital. They reviewed the files of 381 patients with acromegaly and collected information about their blood tests, hormone levels, tumor size, and treatments. They compared patients who had anemia with those who didn’t to see what differences existed between the two groups.

The researchers looked at several types of information: blood test results showing red blood cell counts, hormone measurements (growth hormone and other pituitary hormones), imaging scans showing tumor size, and details about what treatments patients received. They used statistical methods to figure out which factors were most strongly connected to anemia development.

This approach is useful for understanding patterns in a large group of patients, but it can’t prove that one thing directly causes another—it can only show associations. The researchers also did a special analysis to separate out which factors were most important when considering multiple factors together.

Understanding how often anemia occurs in acromegaly and what causes it is important because anemia can make people feel tired and weak. By identifying which patients are at highest risk, doctors can monitor them more carefully and potentially catch problems earlier. This study provides a foundation for future research to figure out exactly why acromegaly causes anemia in so many patients.

This study has good strengths: it included a large number of patients (381) from a specialized medical center with detailed medical records. However, there are some limitations to keep in mind. Because it looked backward at existing records rather than following patients forward over time, researchers couldn’t control all the factors that might affect results. The study couldn’t explain why 77% of anemia cases had no clear cause, which suggests the connection between acromegaly and anemia is more complex than currently understood. The findings come from one medical center, so results might be different in other populations or countries.

What the Results Show

The study found that anemia was very common in acromegaly patients—more than half had it. Of the 219 patients with anemia, most (67%) had normocytic anemia, which means their red blood cells were normal-sized but just not numerous enough. About 45% had mild anemia, while 11% had moderate anemia and less than 1% had severe anemia.

When researchers looked at different types of anemia, they found iron deficiency anemia in 18.7% of anemic patients, with women affected more often than men (22.5% of women vs. 14.3% of men). A small number (4%) had thalassemia minor, a genetic blood condition. Surprisingly, no patients had anemia from vitamin B12 or folate deficiency, which are common causes of anemia in the general population.

Patients with anemia had noticeably different tumor characteristics compared to those without anemia. They were more likely to have larger tumors (macroadenomas), tumors that had invaded surrounding tissues, and tumors that remained after surgery. They also had higher levels of growth hormone and other pituitary hormones even after treatment, suggesting their disease was harder to control.

These patients needed more aggressive treatment: 71% were on somatostatin receptor ligands (medications that reduce growth hormone), compared to 50% of non-anemic patients. More anemic patients also received dopamine agonists (another type of medication) and radiation therapy. Additionally, anemic patients were more likely to have other pituitary gland problems (hypopituitarism), meaning their pituitary wasn’t working properly in other ways.

The study found some interesting differences between men and women. Women were more likely to have microcytic anemia (small red blood cells), while men and women had roughly equal rates of normocytic anemia. Cancer was slightly more common in patients with anemia (17% vs. 10.4%), though this difference wasn’t statistically significant enough to be certain it wasn’t due to chance.

When researchers analyzed which factors were most predictive of anemia, three stood out as independent predictors: having a larger tumor (macroadenoma), being treated with somatostatin receptor ligands, and taking thyroid hormone replacement therapy. These factors remained important even when researchers accounted for other variables.

This is one of the first large studies to systematically examine anemia in acromegaly patients. Previous research suggested that growth hormone and related factors might affect red blood cell production, but there was limited data on how common this problem actually is. This study confirms that anemia is indeed a frequent issue in acromegaly—affecting more than half of patients—which is much higher than in the general population. The finding that most cases remain unexplained suggests that the relationship between acromegaly and anemia is more complex than previously thought and likely involves multiple mechanisms.

The biggest limitation is that this study looked backward at existing medical records rather than following patients forward over time, which limits what we can conclude about cause and effect. The study couldn’t explain why 77% of anemia cases had no identifiable cause—this is a major gap in understanding. Because the study was done at one specialized medical center, the results might not apply to all acromegaly patients everywhere. The study didn’t have detailed information about diet, supplements, or other factors that might affect anemia. Additionally, the cross-sectional nature means we’re seeing a snapshot in time rather than how anemia develops over the course of the disease.

The Bottom Line

If you have acromegaly, ask your doctor to regularly check your blood cell counts (hemoglobin and hematocrit levels) as part of your routine care. This is a moderate-confidence recommendation based on how common anemia is in this population. If anemia is detected, work with your doctor to identify the cause—though in most cases the cause won’t be obvious. Ensure you’re getting adequate iron, vitamin B12, and folate in your diet, though supplementation should only be done under medical supervision. Continue taking prescribed acromegaly treatments as directed, since treatment intensity appears related to anemia risk.

This research is most important for people already diagnosed with acromegaly and their doctors. It’s particularly relevant for those with larger tumors or those requiring intensive treatment. People without acromegaly don’t need to apply these findings to themselves. If you have symptoms of anemia (fatigue, shortness of breath, dizziness) and acromegaly, mention this to your doctor.

Anemia in acromegaly appears to develop gradually as the disease progresses, rather than suddenly. If anemia is identified and treated, improvements in energy and symptoms might take weeks to months depending on the cause and treatment approach. However, this study doesn’t provide specific information about how quickly anemia develops or improves with treatment.

Want to Apply This Research?

  • If you have acromegaly, track your hemoglobin and hematocrit levels (from blood tests) every 3-6 months. Record the date, values, and any symptoms like fatigue or shortness of breath. Note any changes in your acromegaly medications or treatments, as these appear connected to anemia risk.
  • Work with your healthcare team to ensure regular blood work is scheduled and completed. If anemia is detected, use the app to track dietary iron intake and any prescribed treatments. Set reminders for medication adherence, especially for acromegaly treatments, since treatment intensity is linked to anemia development.
  • Create a long-term tracking system that monitors blood test results alongside acromegaly treatment changes. Flag any new symptoms of anemia (unusual fatigue, shortness of breath, dizziness) to discuss with your doctor. Track correlations between treatment intensity and anemia development to help your medical team understand your individual patterns.

This research is for informational purposes only and should not replace professional medical advice. Anemia in acromegaly is a complex condition that requires individualized evaluation and treatment by qualified healthcare providers. If you have acromegaly or suspect you may have anemia, consult with your doctor or endocrinologist before making any changes to your treatment plan. This study describes patterns in one patient population and may not apply to all individuals. Do not start, stop, or change any medications based on this information without medical supervision.