SEARCH For Diabetes In Youth Study finds more at risk of developing diabetic peripheral neuropathy than previously thought.
More children and adolescents are being diagnosed with type 1 and type 2 diabetes than ever before. Diabetes has significant associated morbidity and mortality; however, the prevention and early treatment of diabetic complications has the potential to improve quality of life and increase life expectancy. Diabetic peripheral neuropathy (DPN) often affects the legs and feet, and patients report pain, numbness, and tingling. Patients may also experience problems with their digestive system, urinary tract, blood vessels and heart. DPN affects up to 26% of newly diagnosed adults, but it’s prevalence is not well studied in children and adolescents. Therefore, researchers set out to examine cross-sectional and longitudinal risk factors for DPN. The aims of the study were to 1) estimate the prevalence of DPN in youth with type 1 and type 2 diabetes, and 2) identify risk factors associated with the presence of DPN in a multiethnic cohort of youth with diabetes enrolled in the SEARCH study.
The SEARCH study is a population-derived prospective cohort study following children and adolescents of diverse races and ethnicities diagnosed with diabetes before the age of 20 years old in the United States. The following inclusion criteria was used: diagnosis of diabetes before age of 20 years old, had a duration of diabetes for at least 5 years, and was 10 years or older. The SEARCH cohort study enrolled over 2,700 individuals and information about their height, weight, waist circumference, blood pressure, DPN, and blood and urine samples were collected. Race and ethnicity were self-reported per a participant survey and questionnaire. DPN was assessed using the Michigan Neuropathy Screening Instrument (MNSI), a validated screening tool. The MNSI is a 15-item questionnaire that scores for deformities, infection, ulcerations, and vibration perception at the distal great toe and ankle reflexes. A score > 2 out of 8 on the MNSI denotes the presence of DPN.
Cross-sectional data collected at cohort visits were used to compare characteristics distinguishing children and adolescents with DPN and those without, stratified by type of diabetes. Wilcoxon two-sample tests were used to compare the distribution of continuous variables and the chi-squared test was used for categorical variables separately for type 1 and type 2 diabetes. In total, there were 1,734 participants with type 1 diabetes and 258 with type 2 diabetes. Approximately 7% of the participants with type 1 diabetes and 22% of the participants with type 2 diabetes had evidence of DPN. For patients in the type 1 diabetes group, those with DPN were older, had a longer duration of diabetes (8.7 vs. 7.8 years, P < 0.0001), higher BMI (26 vs. 24 kg/m2, P < 0.001), higher LDL-c levels (101 vs. 96 mg/dL, P < 0.01) and higher triglycerides (85 vs. 74 mg/dL, P = 0.005). For patients in the type 2 diabetes group, those with DPN were older, had a longer duration of diabetes (8.6 vs. 7.6 years, P = 0.002), and had lower HDL-c (40 vs. 43 mg/dL, P = 0.04) compared to those without DPN. The prevalence of DPN was also higher among males (30%) than females (18%, P= 0.02), and was over double as common in smokers (33%) than non-smokers (15%, P= 0.01).
In conclusion, the prevalence of DPN in this youth cohort with type 1 and type 2 diabetes was 7% and 22%, respectively. Risk factors for the development of DPN among youth with type 1 diabetes included: older age, current smoking status, longer duration of disease, long-term poor glycemic control, and cardiovascular risk factors. While the risk factors for youth with type 2 diabetes included: older age, current smoking status and longer diabetes duration. These results were like previous studies, however the rate of DPN was higher in this study than in former trials. Researchers propose that their use of the MNSI, a more comprehensive assessment tool, recognized more cases of DPN than in using a single-factor test. Results from this study also found that poor glycemic control over time and traditional cardiovascular risk factors are important risk factors that are associated with DPN, not just in the adult population but in youth with diabetes as well. These findings reinforce the need for tighter glycemic control and frequent and thorough check-ups for adolescent patients with both type 1 and type 2 diabetes. Complications from diabetes are often thought to occur more frequently in adults than in children, however with the ever-increasing number of children and adolescents developing diabetes, preventing and treating these complications early is key to improving quality of life and increasing life expectancy.
- Male children and adolescents with type 1 or type 2 diabetes were more likely to develop DPN than females.
- DPN was over two-times as prevalent in smokers than in non-smokers.
- Less favorable lipid profiles were also linked to increased prevalence of DPN.
Jaiswal, Mamta, et al. “Prevalence of and Risk Factors for Diabetic Peripheral Neuropathy in Youth With Type 1 and Type 2 Diabetes: SEARCH for Diabetes in Youth Study.” Diabetes Care 40.9 (2017): 1226-1232.
Jessica Lambert; University of South Florida College of Pharmacy:Doctor of Pharmacy Candidate 2018