The risk of myocardial infarction is enhanced by a synergistic interaction between serum insulin and smoking

Abstract

Objectives: To evaluate the relationship between levels of serum insulin, the homeostasis model assessment (HOMA) and IGF-binding protein-1 (IGFBP-1) as factors related to myocardial infarction (MI) risk, and their interaction with lifestyle-related risk factors. Design: The Stockholm epidemiology programme (SHEEP), a case-control study, consisting of 749 first-time MI cases (510 men, 239 women) and 1101 healthy controls (705 men, 396 women) was used. Methods: The risk of developing MI was assessed by calculating odds ratios (OR) and synergistic interactions (SI) between serum insulin, IGFBP-1, HOMA and other variables related to MI risk (including smoking) in men and women. Results: Subjects with elevated levels of insulin and HOMA (. 75th percentile) had increased MI risks when compared with individuals with low levels. ORs for elevated insulin and HOMA (adjusted for age and residential area) for men: insulin 1.6 (95% confidence interval (CI) 1.3-2.1) and HOMA 1.5 (95% CI 1.1-1.9) and for women: insulin 2.1 (95% CI 1.5-2.9) and HOMA 1.9 (95% CI 1.3 -2.8). Women with low levels of IGFBP-1 (,10th percentile) showed a tendency towards elevated MI risk even if this was not statistically significant (OR 1.5 (95% CI 0.9-2.6)). Smokers with high levels of serum insulin had greatly increased MI risk (OR for men: 4.7 (95% CI 3.0-7.2) and OR for women: 8.1 (95% CI 4.5 -14.8)). SI scores based upon these interactions were statistically significant. Conclusions: These results might have preventive cardiovascular implications as they clearly suggest that subjects with insulin resistance are particularly susceptible to the hazards of smoking.

Gender differences in the relation of insulin‐like growth factor binding protein‐1 to cardiovascular risk factors: a population‐based study

“…Separate analyses, however, showed that waist was significantly negatively correlated to IGFBP-1 in men. 51 A positive correlation between IGFBP-1 and total cholesterol was also found in women, which could be explained by the relationship to HDL cholesterol. 5,6,22,45 The most consistent finding concerning serum lipids was the positive correlation between IGFBP-1 and HDL-C in women.…”

“…51 Identifying the extent and causes of sex differences in biochemical, physiological and social outcomes is necessary in understanding variability in susceptibility to a disease and its cause. Men have in general a more disadvantageous cardiovascular risk profile than women.…”

Insulin-like growth factor binding protein-1 is a long-term predictor of heart failure in survivors of a first acute myocardial infarction and population controls

“…Total cholesterol, triglycerides and TNFα levels were determined from blood samples drawn by venous puncture undertaken during the health examination as previously described elsewhere [14,15]. Serum samples were stored at − 70°C until analyses for IGFBP-1 and insulin were performed.…”

Vascular Complications of Diabetes

“…167 Moreover, there may be a synergistic effect of cigarette smoking and insulin resistance in the development of atherosclerosis, suggesting a particularly important role in patients with diabetes mellitus. 168 Smoking cessation interventions should be pursued aggressively, for the benefits in patients with diabetes mellitus at least match those found in patients without diabetes mellitus. 169 A variety of smoking cessation interventions are available, including counseling, nicotine replacement therapy, antidepressants (buproprion), and the nicotine partial receptor agonist, varenicline.…”