Association of Serum C-Peptide Concentrations with Cancer Mortality Risk in Pre-Diabetes or Undiagnosed Diabetes

Abstract

BackgroundKnown associations between diabetes and cancer could logically be attributed to hyperglycemia, hypersecretion of insulin, and/or insulin resistance. This study examined the relationship between initial glycemic biomarkers among men and women with impaired fasting glucose or undiagnosed diabetes and cancer mortality during follow up.MethodsThe cohort included subjects aged 40 years and above from the Third National Health and Nutrition Examination Survey (NHANES III) with fasted serum glucose >100 mg/dl without the aid of pharmaceutical intervention (insulin or oral hypoglycemics). Cancer mortality was obtained from the NHANES III-linked follow-up database (up to December 31, 2006). A Cox regression model was applied to test for the associations between cancer mortality and fasting serum glucose, insulin, glycosylated hemoglobin (HbA1c), C-peptide, insulin like growth factor (IGF-1), IGF binding protein 3 (IGFBP3) and estimated insulin resistance.ResultsA total of 158 and 100 cancer deaths were recorded respectively from 1,348 men and 1,161 women during the mean 134-month follow-up. After adjusting for the effect of age and smoking in women, all-cause cancer deaths (HR: 1.96 per pmol/ml, 95% CI: 1.02–3.77) and lung cancer deaths (HR: 2.65 per pmol/ml, 95% CI: 1.31–5.36) were specifically associated with serum C-peptide concentrations. Similar associations in men were not statistically significant. Serum glucose, HbA1c, IGF-1, IGFBP3 and HOMA were not independently related to long-term cancer mortality.ConclusionC-peptide analyses suggest a modest association with both all-cause and lung cancer mortality in women but not in men. Further studies will be required to explore the mechanisms.

In Patients Younger Than Age 55 Years With Lymph Node–Negative Breast Cancer, Proliferation by Mitotic Activity Index Is Prognostically Superior to Adjuvant!

“…In a Norwegian long-term observational study (147) In line with this, c-peptide is associated with all-cancer mortality (168) and the outcome of breast cancer (169). Serum levels of c-peptide seem to increase the risk of breast cancer in postmenopausal women (170,171), but not in pre-menopausal women (172),(173).…”

Relationship between HbA1c and cancer in people with or without diabetes: a systematic review

“…Hsu et al [17] found no associations between HbA 1c level and lung cancer mortality in a cohort of people with undiagnosed diabetes or impaired fasting blood glucose.…”

“…Eight studies focused on the relationship between HbA 1c and all types of cancer [10][11][12][13][14][15][16][17], and are summarized in Table 2. All studies were adjusted for age, sex and smoking status.…”

“…Four cohort studies [10,14,15,17] reported data regarding HbA 1c in relation to other site-specific cancers. No significant difference in the incidence of lung and prostate cancers was ª 2015 Diabetes UK identified by Joshu et al [10] in people with or without diabetes.…”

The Association between the Serum C-Peptide Level and Bone Mineral Density

“…Further, studies have shown that the basal C-peptide level is significantly elevated among patients with metabolic syndrome and diabetes. Another recent study reported that the serum C-peptide level is independently associated with cardiovascular disease, cancer, and total mortality [14], [15]. However, currently, the metabolic characteristics of serum C-peptide are receiving considerable attention.…”