Prevalence and risk factors of neuropathic pain in survivors of myocardial infarction with pre-diabetes and diabetes. The KORA Myocardial Infarction Registry

The lowest glycemic threshold for and the risk factors associated with neuropathic pain have not been established. The aim of this study was to determine the prevalence and risk factors of neuropathic pain in survivors of myocardial infarction with diabetes, impaired glucose tolerance (IGT), impaired fasting glucose (IFG), normal glucose tolerance (NGT). Subjects aged 25-74 years with diabetes (n = 214) and controls matched for age and sex (n = 212) from the population-based KORA (Cooperative Health Research in the Region of Augsburg) Myocardial Infarction Registry were assessed for neuropathic pain by the Michigan Neuropathy Screening Instrument using its pain-relevant questions and an examination score cutpoint >2. An oral glucose tolerance test was performed in the controls. Among the controls, 61 (28.8%) had IGT (either isolated or combined with IFG), 70 (33.0%) had isolated IFG, and 81 had NGT. The prevalence of neuropathic pain was 21.0% in the diabetic subjects, 14.8% in those with IGT, 5.7% in those with IFG, and 3.7% in those with NGT (overall p < 0.001). In the entire population studied (n = 426), age, waist circumference, peripheral arterial disease (PAD), and diabetes were independent factors significantly associated with neuropathic pain, while in the diabetic group it was waist circumference, physical activity, and PAD (all p < 0.05). In conclusion, the prevalence of neuropathic pain is relatively high among survivors of myocardial infarction with diabetes and IGT compared to those with isolated IFG and NGT. Associated cardiovascular risk factors including abdominal obesity and low physical activity may constitute targets to prevent neuropathic pain in this population.