Incident Cardiac Events and Sleep Disordered Breathing in Diabetic Patients

Introduction

Diabetes mellitus type 2 (T2DM) is an increasing worldwide epidemic already affecting 25.8 million individuals, representing 8.3% of the U.S. population, and including one in four Americans age 65 years and older.1 The T2DM population has a significantly higher incidence of coronary artery disease (CAD), congestive heart failure (CHF),2,3 atrial fibrillation (AF)4, and shorter lifespan frequently attributed to cardiovascular death.8 The American Diabetes Association (ADA) current guidelines,6 including performing at least annual standardized assessments of the traditional core set of cardiovascular risk factors (glycemic control, overweight/obesity, hypertension, dyslipidemia, and alcohol and tobacco use) in the adult diabetic population, are being increasingly adopted by pediatricians involved in the long-term care of diabetic children and teens.9,10 The American Cardiology Community is a long-standing partner of the ADA in cardiovascular preventive strategies, clinical care, and clinical and experimental research related to cardiac complications in patients with T2DM. While the pathology and mechanisms underlying the association between glucose homeostasis and specific myocardial dysfunction remain to be clarified,2 and cardiac service referrals are no longer recommended for routine screenings of incident cardiac events in asymptomatic diabetics at cardiovascular risk due to a previously demonstrated poor cost/benefit ratio of these interventions,6,11 the benefit of multidisciplinary efforts in recognizing and treating novel cardiovascular risk factors cannot be overstated6-8. Of those, sleep-related conditions are currently gaining increased interest and attention, due to a higher prevalence of sleep disorders (including sleep disordered breathing (SDB), reduced sleeping time, and poor sleep quality) and these conditions' associations with cardiac and cardiovascular risk, and similar patterns of association of the same conditions with glucose intolerance, insulin resistance, and diabetes,6,12,13-16 independent of other common characteristics, such as overweight /obesity17 and depression.

Diabetes, SDB and Incident Cardiac Events

SDB probably represents the most common under-recognized, therefore untreated, chronic sleep disorder worldwide. Previous articles in this series18-21 have already reviewed emerging epidemiological and clinical evidence linking SDB with hypertension, CAD, CHF, AF22-31 and SDB with diabetes and insulin resistance.13 This short review aims to increase the cardiology community's interest in causal association research of the independent role of SDB on new onset cardiac disease in asymptomatic T2DM patients, a topic largely unstudied to date.

The first longitudinal, evidence-based clinical research evaluating the independent role of SDB on the onset of incident CHF, CAD, and AF events in patients with T2DM was published in 2013.32 This study, sponsored and conducted by the Cleveland Clinic Foundation, Heart and Vascular Institute (CCF, HVI), examined 834 consecutive asymptomatic T2DM patients with baseline normal stress echocardiograms and comprehensive baseline evaluations (performed between January 2004 and December 2007 and in accordance with correspondent ADA standard care recommendations), thereby confirming no history of cardiac disease in these patients at the time of recruitment in the study. During a median follow-up of approximately five years, patients with SDB showed nearly three times the rate of AF, as compared with non-SDB patients, and a higher hazard of incident CAD (HR=1.9 [1.1-3.3], p=0.03; adjusted HR=2.2 [1.2-3.9], p=0.01) and HF (HR=2.7 [1.1-7.0], p=0.03; adjusted HR = 3.5 [1.4-9.0], p<0.01) after controlling for age, gender, hypertension, smoking, lipid profile, family history of cardiovascular disease, medical treatments, standard of care-related risk factors, and overweight/obesity. Those findings were supported by previously proposed multiple dysregulations of neuroendocrine and immune system activation pathways, linking SDB with cardiac and cardiovascular risk. These included chronic inflammation, macrophage infiltration, adiponectin reduction, leptin elevation, and mitochondrial dysfunction reported as increasing the insulin resistance and the beta cell dysfunction.18-21 Additional proposed mechanisms included impaired clearance of triglyceride-rich lipoproteins and inactivation of the lipoprotein lipase, endothelial dysfunction, and elevated daytime and nocturnal blood pressure.18-21

This same study also showed no differences or significant higher hazard of incident cardiac events in T2DM women, and explained those findings based on previously shown endothelial dysfunction and more pronounced vasoconstriction in response to both hypoxia and stress,33 larger brachial artery diameters (previously identified as a CAD risk factor),34 and/or flow-mediated diameters in T2DM female patients with SDB when compared to their male counterparts.35

While this study had greater female representation, an adequate sample size, and separation of endpoints, as well as carefully explored the differences between SDB vs. non-SDB diabetics related to traditional CAD risk factors, health care access and quality, and treatment differences for existing co-morbidities, it also had multiple limitations, thereby warranting further research. Due to the observational retrospective nature of the study, including relying on electronic health records, data from a single clinical center, and patients residing only in Ohio, as well as reduced data on behavioral risk factors (e.g. diet and exercise practices), and no data on the specific characteristics of the SDB severity, treatment, and incident cardiac events, the findings of this study should be at least further explored and validated in the general U.S diabetic population.

Conclusion

Further research should address the importance of this topic by providing national inferences of the extent and prevalence of SDB and its associated symptoms in the diabetic U.S. population, as well as validating the predictive role of SDB on the incidence of new cardiac and cardiovascular fatality in the U.S. Additionally, multi-site, prospective clinical trials should be designed and conducted by multidisciplinary teams, including experienced endocrinologists, cardiologists, sleep specialists, and clinical epidemiologists, to generate compelling evidence-based conclusions concerning the utility of integrating SDB screening and long-term treatment and follow-up within the endocrinology and/or cardiology practice.

Finally, gender-specific cost/benefit analyses are warranted to address the effectiveness of SDB-specific clinical interventions on the overall quality of life and/or survivorship in patients with T2DM and SDB, independent of other ongoing efforts to prevent/reduce associated CVD risk factors (e.g., overweight/obesity, hypertension, and hyperlipidemia).


References

  1. Centers for Disease Control and Prevention. National diabetes fact sheet: national estimates and general information on diabetes and prediabetes in the United States, 2011. Atlanta, GA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, 2011.
  2. Chiha M, Njeim M, Chedrawy EG. Diabetes and coronary heart disease: a risk factor for the global epidemic. Int J Hypertensn 2012;2012:697240.
  3. Poulsen MK, Henriksen JE, Dahl J, et al. Left ventricular diastolic function in type 2 diabetes mellitus prevalence and association with myocardial and vascular disease. Circ Cardiovasc Imaging 2010;3:24–31.
  4. Huxley RR, Filion KB, Konety S, Alonso A. Meta-analysis of cohort and case-control studies of type 2 diabetes mellitus and risk of atrial fibrillation. Am J Cardiol 2011; 108:56–62.
  5. Engelgau MM, Geiss LS, Saaddine JB, Boyle JP, Benjamin SM, Gregg EW, Tierney EF, Rios-Burrows N, Mokdad AH, Ford ES, Imperatore G, Narayan KM: The evolving diabetes burden in the United States. Ann Intern Med 2004;140: 945–950.
  6. American Diabetes Association. Standards of Medical Care in Diabetes 2014. Diabetes Care 2014 : 37:S14-S80
  7. Bax JJ, Young LH, Frye RL, Bonow RO, Steinberg HO, Barrett EJ, American Diabetes Association. Screening for coronary artery disease in patients with diabetes. Diabetes Care 2007;30:2729–2736
  8. Buse JB, Ginsberg HN, Bakris GL, et al., American Heart Association, American Diabetes Association. Primary prevention of cardiovascular diseases in people with diabetes mellitus: a scientific statement from the American Heart Association and the American Diabetes Association. Diabetes Care 2007;30:162–172.
  9. Magge SN. Cardiovascular risk in children and adolescents with type 1 and type 2 diabetes mellitus. Curr Cardiovasc Risk Rep 2012;6:591–600.
  10. Liese AD, D'Agostino RB, Jr, Hamman RF, Kilgo PD, Lawrence JM, Liu LL, et al. The burden of diabetes mellitus among US youth: prevalence estimates from the SEARCH for Diabetes in Youth Study. Pediatrics 2006;118:1510–8.
  11. Young LH, Wackers FJ, Chyun DA, et al., DIAD Investigators Cardiac outcomes after screening for asymptomatic coronary artery disease in patients with type 2 diabetes: the DIAD study: a randomized controlled trial. JAMA 2009; 301:1547–155.
  12. Ali MK, Bullard KM, Saaddine JB, Cowie CC, Imperatore G, Gregg EW. Achievement of goals in U.S. diabetes care, 1999–2010. N Engl J Med 2013; 368:1613–1624.
  13. Drager L . Obstructive Sleep Apnea, Metabolic Syndrome and Diabetes February 24 2014 http://apnea.cardiosource.org/Hot-Topics/2014/02/Obstructive-Sleep-Apnea-Metabolic-Syndrome-and-Diabetes.aspx
  14. Heffner JE. Prevalence of diagnosed sleep apnea among patients with type 2 diabetes in primary care. Chest J 2012; 141:1414
  15. Foster GD, Borradaile KE, Sanders MH, et al. A randomized study on the effect of weight loss on obstructive sleep apnea among obese patients with type 2 diabetes: the Sleep AHEAD study. Arch Intern Med 2009; 169:1619.
  16. Drager LF, Togeiro SM, Polotsky VY, Lorenzi-Filho G. Obstructive sleep apnea. J Am Coll Cardiol 2013; 62:569–576.
  17. Seicean S, Kirchner L, Gottlieb DJ, Punjabi N, Resnick H, Sanders M, Budhiraja R, Singer M, Redline S. Sleep-Disordered Breathing and Impaired Glucose Metabolism in Normal-Weight and Overweight/Obese Individuals The Sleep Heart Health Study. Diabetes Care 2008; 31:1001-1006.
  18. Javaheri S, Redline S. Incidence and Prevalence of Sleep Apnea in cardiovascular Patients. http://apnea.cardiosource.org . Nov 2012. Accessed at http://apnea.cardiosource.org/Hot-Topics/Archive.aspx
  19. Mehra R .Sleep Disordered Breathing and AFib: Emerging Data, Elucidating Mechanisms and Epidemiology. http://apnea.cardiosource.org . Feb 2013 Accessed at http://apnea.cardiosource.org/Hot-Topics/2013/02/Sleep-Disordered-Breathing-and-AFib.aspx
  20. Fang E, Loo G, Lee CH. Sleep Apnea and the Heart—the Singapore Experience. http://apnea.cardiosource.org. Nov 2013. Accessed at http://apnea.cardiosource.org/Hot-Topics/2013/11/Sleep-Apnea-and-the-Heart-the-Singapore-Experience.aspx
  21. Smith DN, Bazan I, Carollo M, Sleep Apnea Impact on the Updated Heart Failure Guidelines. http://apnea.cardiosource.org. Jan 2014. Accessed http://apnea.cardiosource.org/Hot-Topics/2014/01/Sleep-Apnea-Impact-on-the-Updated-HF-Guidelines.aspx
  22. Shah NA, Yaggi HK, Concato J, Mohsenin V. Obstructive sleep apnea as a risk factor for coronary events or cardiovascular death. Sleep Breath 2010; 14:131-136.
  23. Martinez D, Klein C, Rahmeier L, da Silva RP, Fiori CZ, Cassol CM, Gonçalves SC, Bos AJ. Sleep apnea is a stronger predictor for coronary heart disease than traditional risk factors. Sleep Breath 2012; 16:695-701.
  24. Peker Y, Hedner J, Norum J, Kraiczi H, Carlson J. Increased incidence of cardiovascular disease in middle-aged men with obstructive sleep apnea: a 7-year follow-up. Am J Respir Crit Care Med 2002; 166:159–165.
  25. Gottlieb DJ, Yenokyan G, Newman AB,O'Connor GT, Punjabi NM, Quan SF, Redline S, Resnick HE, Tong EK, Diener-West M, Shahar E. Prospective study of obstructive sleep apnea and incident coronary heart disease and heart failure: the Sleep Heart Health Study. Circulation 2010; 122:352–360.
  26. Hoffstein V, Mateika S. Cardiac arrhythmias, snoring, and sleep apnea. Chest 1994; 106:466-471.
  27. Namtvedt SK, Randby A, Einvik G, Hrubos-Strøm H, Somers VK, Røsjø H, Omland T. Cardiac arrhythmias in obstructive sleep apnea (from the Akershus Sleep Apnea Project). Am J Cardiol 2011; 108:1141-1146.
  28. Mehra R, Benjamin EJ, Shahar E, Gottlieb DJ, Nawabit R, Kirchner HL, Sahadevan J Redline S, Sleep Heart Health Study. Association of nocturnal arrhythmias with sleep-disordered breathing: The Sleep Heart Health Study. Am J Respir Crit Care Med 2006; 173:910-916.
  29. Sin DD, Fitzgerald F, Parker JD, Newton G, Floras JS, Bradley TD. Risk factors for central and obstructive sleep apnea in 450 men and women with congestive heart failure. Am J Respir Crit Care Med 1999; 160:1101-1106.
  30. Wang H, Parker JD, Newton GE, Floras JS, Mak S, Chiu KL, Ruttanaumpawan P, Tomlinson G, Bradley TD. Influence of obstructive sleep apnea on mortality in patients with heart failure. J Am Coll Cardiol 2007; 49:1625-1631.
  31. Monahan K, Redline S. Role of obstructive sleep apnea in cardiovascular disease. Curr Opin Cardiol 2011; 26:541-547.
  32. Seicean S, Strohl K, Seicean A, Gibby C, Marwick TH. "Sleep Disordered Breathing as a Risk for Incident Cardiac Events in Diabetics with a Normal Exercise Echocardiogram." Am J Cardiol 2013; 111:1214-20.
  33. Levenson J, Pessana F, Gariepy J, Armentano R, Simon A. Gender differences in wall shear-mediated brachial artery vasoconstriction and vasodilation. J Am Coll Cardiol 2001; 38:1668-1674.
  34. Holubkov R, Karas RH, Pepine CJ, Rickens CR, Reichek N, Rogers WJ, Sharaf BL, Sopko G, Merz CN, Kelsey SF, McGorray SP, Reis SE. Large brachial artery diameter is associated with angiographic coronary artery disease in women. Am Heart J 2002; 143:802-807
  35. Faulx MD, Larkin EK, Hoit BD, Aylor JE, Wright AT, Redline S. Sex influences endothelial function in sleep-disordered breathing. Sleep 2004; 27:1113-1120.

Keywords: Cardiovascular Diseases, Coronary Artery Disease, Diabetes Mellitus, Type 2, Dyslipidemias, Heart Failure, Hypertension, Obesity, Overweight


< Back to Listings