Carbohydrate, Lipid, and Apolipoprotein Biomarkers in Blood and Risk of Thyroid Cancer: Findings from the AMORIS Cohort

Abstract

Background: Previous studies have examined the link between blood metabolic biomarkers and risk of thyroid cancer, with inconclusive results. We performed a cohort study based on the Swedish Apolipoprotein-Related Mortality Risk (AMORIS) Cohort, including 561,388 individuals undergoing health examinations during 1985–1996 with a follow-up of >30 years. Methods: Newly diagnosed cases of thyroid cancer were identified from the Swedish Cancer Register. We assessed the associations of nine blood biomarkers of carbohydrate, lipid, and apolipoprotein metabolism measured at the time of health examinations with the subsequent risk of thyroid cancer and demonstrated the temporal trend of these biomarkers during the 30 years before diagnosis of thyroid cancer. Results: After multivariable adjustment, there was a lower risk of thyroid cancer, per standard deviation increase in total cholesterol (TC; HR 0.91; 95%CI 0.82–0.99) and HDL-C (HR 0.86; 95%CI 0.75–0.99). During the 20 to 30 years before diagnosis, patients with thyroid cancer, as a group, demonstrated constantly lower levels of TC and HDL-C, compared to controls. Further, patients with thyroid cancer demonstrated declining levels of these biomarkers during the ten years before diagnosis, whereas controls demonstrated stable or increasing levels. Conclusions: Taken together, we found blood levels of TC and HDL-C to be associated with the risk of thyroid cancer and that there was a declining level of metabolic biomarkers during the 10 years before diagnosis of thyroid cancer.

Do metabolic factors increase the risk of thyroid cancer? a Mendelian randomization study

“…( 32 ). Some retrospective observational studies have reported an association between total cholesterol ( 31 ) and apolipoprotein A1 ( 33 ) with thyroid cancer, which is somewhat inconsistent with the results of our study. In the observational study, HDL may be a confounding factor for other lipid profiles.…”

“…For instance, a Korean epidemiological study discovered that obese women with low HDL cholesterol levels were at a heightened risk of developing thyroid cancer ( 29 , 30 ). Similarly, the Swedish Apolipoprotein-Related Mortality Risk (AMORIS) Cohort study demonstrated that thyroid cancer risk was associated with blood levels of total cholesterol (TC) and HDL-C ( 31 ). HDL-C level was found to be a statistically significant independent predictor of thyroid cancer in a model developed by Zhang et al.…”

The Role of Apolipoproteins in the Commonest Cancers: A Review

“…Further studies confirmed that reduced APOA1 levels were associated with a worse prognosis and aggressive thyroid tumor characteristics [176]. Nevertheless, the previous findings contradict with a recent study that found no association between APOA1, APOB, or APOB/APOA1 levels and the risk of thyroid cancer [177]. In fact, it was found that elevated HDL-C and cholesterol levels, which are regulated by APOA1, were associated with a reduced thyroid cancer risk [177].…”

Assessment of causal association between differentiated thyroid cancer and disordered serum lipid profile: a Mendelian randomization study

“…On the other hand, in some previous studies, the lower levels of TC in thyroid cancer cases might be partially attributed to a reverse causal relationship, where thyroid cancer patients showed a decrease in all lipid biomarker (including TC) levels studied in the decade before cancer diagnosis, while the control group showed a sustained increase in TC levels during the same period due to aging. A large-scale cohort study based on the Swedish AMORIS cohort with 30 years of follow-up found that a higher level of TC and HDL-C was negatively correlated with a lower risk of thyroid cancer ( 7 ). However, a recent meta-analysis of 42 studies showed that there was no relationship between TC risk and dyslipidemia ( 10 ).…”

“…Researchers have found that a disordered serum lipid profile may be related to the thyroid gland ( 6 , 7 ). There are generally seven serum lipid tests in medicine: triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein A1 (Apo A1), apolipoprotein B (Apo B), and ratio of Apo B to Apo A1.…”