Increased mortality in acromegaly is due to vascular and respiratory disease and is normalised by control of GH levels—A retrospective analysis from the UK Acromegaly Register 1970–2016

Context

Epidemiological studies involving patients with acromegaly have yielded conflicting results regarding cancer incidence and causes of mortality in relation to control of growth hormone (GH) excess.

Objective

The objective of this retrospective cohort study is to clarify these questions and identify goals for treatment and monitoring patients.

Methods

We studied 1845 subjects from the UK Acromegaly Register (1970–2016), obtaining cancer standardised incidence rates (SIR) and all causes standardised mortality rates (SMR) from UK Office for National Statistics, to determine the relationship between causes of mortality—age at diagnosis, duration of disease, post-treatment and mean GH levels.

Results

We found an increased incidence of all cancers (SIR, 1.38; 95% CI: 1.06–1.33, p < .001), but no increase in incidence of female breast, thyroid, colon cancer or any measure of cancer mortality. All-cause mortality rates were increased (SMR, 1.35; 95% CI: 1.24–1.46, p < .001), as were those due to vascular and respiratory diseases. All-cause, all cancer and cardiovascular deaths were highest in the first 5 years following diagnosis. We found a positive association between post-treatment and mean treatment GH levels and all-cause mortality (p < .001 and p < .001), which normalised with posttreatment GH levels of <1.0 µg/L or meantreatment GH levels of <2.5 µg/L.

Conclusion

Acromegaly is associated with increased incidence of all cancers but not thyroid or colon cancer and no increase in cancer mortality. Excess mortality is due to vascular and respiratory disease. The risk is highest in the first 5 years following diagnosis and is mitigated by normalising GH levels.