PUBHEPI 2410 Epidemiology

1.Reduction in the The Incidence of Type 2 DM with Lifestyle Intervention or Metformin

Study synopsis

This is a randomized controlled trial to assess the effects of lifestyle modification and metformin in the prevention of diabetes in high risk individuals. The hypothesis was that lifestyle intervention or metformin would prevent or delay the development of diabetes. 3,234 persons with elevated fasting and post-load glucose concentrations were assigned to receive placebo, receive metformin, or participate in an intensive lifestyle modification program. The average follow up was 2.8 years. The study found that both metformin and lifestyle intervention did reduce the incidence of diabetes. Lifestyle intervention was significantly more effective than metformin.

2.Risk for major adverse cardiac events in select surgical patients

Hawn et al. (2013) conducted a retrospective cohort study of patients undergoing noncardiac surgery to determine risk for major adverse cardiac events (MACE) within 30 days after surgery and the relationship to time from stent to surgery with adjustment for stent type, surgical characteristics, cardiac risk factors, and comorbid conditions. The cohort consisted of patients undergoing noncardiac surgery within 24 months following coronary stent placement who had MACE compared to those did not have MACE.

This study calculated odds ratios (ORs), which is a little confusing to me because Friis and Sellers (2014) describe ORs for case-control studies, not retrospective cohort studies. However, using ORs in this study makes sense because the researchers are trying to determine the odds of MACE given twelve variables. The study concluded that the top 3 variables that were most strongly associated with MACE were nonelective surgical admission, history of myocardial infarction in the 6 months preceding surgery, and a revised cardiac risk index greater than 2.

 

1.Diabetes type 2 can be countered in different ways, either the use of drugs such as metformin or changing lifestyles. The study carried out placed a large group of people into three categories: receiving a placebo, a lifestyle change program and the administration of metformin (Umpierrez et al., 2014). Use of placebo is important as a control in determining the effects of the other two approaches. Upon a follow-up, this study concludes that use of lifestyle change and taking metformin are effective in the reduction of type 2 diabetes. According to Dunkley et al., (2014), the lifestyle change program may involve high physical activity and take note of the diet composition to avoid fat accumulation as well as excess blood sugars that might damage glucose receptors and result in type 2 diabetes. Use of metformin (an antidiabetic drug) although also reduces diabetes type 2 incidences, its efficiency is low as compared to lifestyle change program.

2.In the retrospective study conducted to determine the major adverse effects in noncardiac surgery, statistical analysis on odds ratio was carried out. This statistical analysis was aimed at determining the relative proportion of the study population who were at risk of developing major adverse cardiac effects (Hawn et al., 2013). It is evident that confounding variables are a barrier to a successful study. The numerous limitations associated with a clinical study may make it difficult to draw meaningful recommendations. Generally, randomized trials generate more meaningful conclusions as opposed to other studies which mostly generate the hypothesis (Pearse et al., 2014). Of great importance is the follow-up period whereby it is necessary to minimize the rate of loss in follow-up.

References

Dunkley, A. J., Bodicoat, D. H., Greaves, C. J., Russell, C., Yates, T., Davies, M. J., & Khunti, K. (2014). Diabetes prevention in the real world: effectiveness of pragmatic lifestyle interventions for the prevention of type 2 diabetes and of the impact of adherence to guideline recommendations. Diabetes care, 37(4), 922-933.

Umpierrez, G., Povedano, S. T., Manghi, F. P., Shurzinske, L., & Pechtner, V. (2014). Efficacy and safety of dulaglutide monotherapy versus metformin in type 2 diabetes in a randomized controlled trial (AWARD-3). Diabetes care, 37(8), 2168-2176.

Hawn, M.T., Graham, L.A., Richman, J.S., Itani, K.M., Henderson, W.G., & Maddox, T.M. (2013). Risk of major adverse cardiac events following noncardiac surgery in patients with coronary stents. JAMA, 310(14), 1462-1472. doi: 10.1001/jama.2013.278787.

Pearse, R. M., Harrison, D. A., MacDonald, N., Gillies, M. A., Blunt, M., Ackland, G., & Hinds, C. (2014). Effect of a perioperative, cardiac output–guided hemodynamic therapy algorithm on outcomes following major gastrointestinal surgery: A randomized clinical trial and systematic review. Jama, 311(21), 2181-2190.