Hypertension in Patients with Diabetes

Dr. Page is an associate professor of clinical pharmacy and physical medicine and a clinical specialist, Division of Cardiology, University of Colorado Health Sciences Center, Schools of Pharmacy and Medicine.

Morning Hypertension and Diabetes: Powerful Predictor for Future Complications

Hypertension frequently coexists with many cardiovascular disease (CVD) risk factors. In fact, the rate of risk factor clustering is about 4 times that which would occur by chance alone.¹ In a Canadian study of hypertensive patients aged 35 years or older who were free from clinical evidence of CVD, 56% were obese with a body mass index of 30 mg/m² or higher or had diabetes or hyperlipidemia.² With their knowledge base and training, pharmacists are very familiar with the closely related combinations of risk factors such as hypertension, hyperlipidemia, diabetes, and obesity, which define the metabolic syndrome.

Research suggests that a strong association between hypertension and diabetes exists in which at least 15% of hypertensive patients have concomitant diabetes.² Furthermore, patients with hypertension appear to develop diabetes more frequently than nonhypertensives, independent of any specific treatment. Hypertension occurs approximately twice as frequently in individuals with diabetes as those without, in which the prevalence has been estimated to be as high as 70% to 80% in patients with type 2 diabetes.^3,4 Nonetheless, a concomitant diagnosis of hypertension in a patient with diabetes can substantially increase the risk for the development of both microvascular (eg, neuropathy, nephropathy, and retinopathy) and macrovascular (eg, heart disease, stroke and peripheral vascular disease, and diabetic foot infections) complications.

Impact of Morning Hypertension

When evaluating the specific type of hypertension and its impact on health outcomes, data have suggested a possible link between morning hypertension (MH) and an increased risk for complications in patients with diabetes. In a study of 170 patients with both type 2 diabetes and hypertension, Kamoi and colleagues found that, compared with those without MH, those with MH demonstrated a 4 to 6 times higher risk for nephropathy demonstrated as microalbuminuria and clinical albuminuria, retinopathy, coronary heart disease, and CVD (P <.01).⁵ The prevalence of nephropathy in all study participants was highly associated with systolic MH (P <.001). In patients with type 1 diabetes, the investigators found similar findings.⁶ Based on an evaluation of 53 patients, Kamoi and colleagues demonstrated that those with MH had a significantly higher risk for nephropathy with microalbuminuria and/or clinical albuminuria as well as retinopathy (P <.01), compared with those patients without MH.

Optimal Blood Pressure Control Is Necessary

Finally, large hypertension trials have suggested that blood pressure (BP) control is often suboptimal in diabetic hypertensive patients.^7-10 The results of the National Health and Nutrition Examination Survey 2003?2004 found BP control (<130/80 mm Hg) was achieved in only 33.2% of treated hypertensive diabetic individuals, a percentage substantially lower than the BP control rate for all treated hypertensive individuals.¹¹

Based on these findings, it appears that patients with diabetes and hypertension, particularly with MH, should be especially targeted for more intensive management of their hypertension. One particular strategy that may benefit this patient population is home BP monitoring, which could not only enhance medication adherence but assist with classifying hypertensive status and better explain the risk for diabetic complications.

References

1. Schmieder RE, Ruilope LM. Blood pressure control in patients with comorbidities. J Clin Hypertens (Greenwich). 2008;10:624-631.
2. Weycker D, Nichols GA, O'Keeffe-Rosetti M, et al. Risk-factor clustering and cardiovascular disease risk in hypertensive patients. Am J Hypertens. 2007;20:599-607.
3. Sowers JR, Epstein M, Frohlich ED. Diabetes, hypertension, and cardiovascular disease: an update. Hypertens. 2001;37:1053-1059.
4. Mancia G, De Backer G, Dominiczak A, Cifkova R, Fagard R, Germano G. 2007 Guidelines for the management of arterial hypertension: The Task Force for the Management of Arterial Hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC). Eur Heart J. 2007;28:1462-1536.
5. Kamoi K, Miyakoshi M, Soda S, Kaneko S, Nakagawa O. Usefulness of home blood pressure measurement in the morning in type 2 diabetic patients. Diabetes Care. 2002;25:2218-23.
6. Kamoi K, Imamura Y, Miyakoshi M, Kobayashi C. Usefulness of home blood pressure measurement in the morning in type 1 diabetic patients. Diabetes Care. 2003;26:2473-2475.
7. Bakris GL, Gaxiola E, Messerli FH, et al. Clinical outcomes in the diabetes cohort of the INternational VErapamil SR-Trandolapril study. Hypertens. 2004;44:637-642.
8. Andersen NH, Poulsen PL, Knudsen ST, et al. Long-term dual blockade with candesartan and lisinopril in hypertensive patients with diabetes: the CALM II study. Diabetes Care. 2005;28:273-277.
9. Dahlof B, Sever PS, Poulter NR, et al. Prevention of cardiovascular events with an antihypertensive regimen of amlodipine adding perindopril as required versus atenolol adding bendroflumethiazide as required, in the Anglo-Scandinavian Cardiac Outcomes Trial-Blood Pressure Lowering Arm (ASCOT-BPLA): a multicentre randomized controlled trial. Lancet. 2005;366:895-906.
10. Maahs DM, Kinney GL, Wadwa P, et al. Hypertension prevalence, awareness, treatment, and control in an adult type 1 diabetes population and a comparable general population. Diabetes Care. 2005;28:301-306.
11. Nelson RG, Knowler WC, Pettit DJ, et al. Kidney diseases in diabetes. In: Diabetes in America. Bethesda, MD: National Institutes of Health Publication; 1995.

Women with Diabetes and Hypertension: True "Femmes Fatales"

The worldwide incidence of type 2 diabetes continues to increase at an alarming rate with similar findings reported for blood pressure (BP) and hypertension.^1-3 As part of the metabolic syndrome, the marriage between hypertension and diabetes is a close but complex relationship.³ One study in men found that the risk of developing type 2 diabetes rises with the increasing number of metabolic abnormalities but that BP per se was not independently associated with new-onset diabetes.⁴

This may not be true, however, for women. Data from the Women?s Health Study suggest that, compared with women with optimal BP, those with hypertension exhibited a 2.39-fold increased risk for developing type 2 diabetes independent of both body mass index and other components of the metabolic syndrome (P <.0001).⁵

Cardiovascular Disease and Diabetes

Over the last quarter of a century, mortality associated with cardiovascular disease (CVD) in the United States has declined among men with and without diabetes.⁶ For women, however, this decrease has been demonstrated only in those without diabetes.⁷ Furthermore, the relative risk for fatal diabetes-associated coronary heart disease is 50% higher in women, compared with men.⁸

These sex-related disparities in CVD mortality may be linked with control of modifiable risk factors. Data from the TRIAD (Translating Research Into Action for Diabetes) Study found that women with type 2 diabetes and CVD were more likely to have systolic blood pressures (SBP) exceeding 140 mm Hg and lowdensity lipoprotein (LDL) concentrations >130 mg/dL, compared with men.⁹ In a cross-sectional analysis of 44,893 patients with type 2 diabetes, Gouni-Berthold and colleagues found that women with established CVD were significantly more likely than men to have SBP, LDL level, and hemoglobin A1C exceeding 140 mm Hg (P <.0001), 130 mg/dL (P <.0001), and 8% (P = .0009), respectively.¹⁰

Blood Pressure Control Is Vital

Based on these findings, it appears that the presence of diabetes negates the protective effect of female gender on the risk of CVD. In order to improve the gender disparity in CVD-associated mortality, more aggressive management of CVD in women with diabetes will be necessary. One particular modifiable risk factor worth targeting is tighter BP control in women with hypertension. With the advent of affordable and accurate home BP monitoring devices, women with both diabetes and hypertension can more closely monitor their BP with greater accuracy and convenience.

Through the use of such technology, patients can take a more active role in their health care, thus increasing their chances for adherence to their antihypertensive medications and improved CVD outcomes. Because these devices are typically sold in community pharmacies, pharmacists are in a unique position to recommend an appropriate device and to educate patients on its proper use.

References

1. Zimmet P, Alberti KG, Shaw J. Global and societal implications of the diabetes epidemic. Nature. 2001;414:782-787.
2. Ezzati M, Lopez AD, Rodgers A, Vander Hoorn S, Murray CJ. Selected major risk factors and global and regional burden of disease. Lancet. 2002;360:1347-1360.
3. Danaei G, Lawes CM, Vander Hoorn S, Murray CJ, Ezzati M. Global and regional mortality from ischaemic heart disease and stroke attributable to higher-than-optimum blood glucose concentration: comparative risk assessment. Lancet. 2006;368:1651-1659.
4. Sattar N, Gaw A, Scherbakova O, et al. Metabolic syndrome with and without C-reactive protein as a predictor of coronary heart disease and diabetes in the West of Scotland Coronary Prevention Study. Circulation. 2003;108:414-419.
5. Conen D, Ridker PM, Mora S, Buring JE, Glynn RJ. Blood pressure and risk of developing type 2 diabetes mellitus: the Women's Health Study. Eur Heart J. 2007;28:2937-2943.
6. Gu K, Cowie CC, Harris MI. Diabetes and decline in heart disease mortality in US adults. JAMA. 1999;281:1291-1297.
7. Gregg EW, Gu Q, Cheng YJ, Narayan KM, Cowie CC. Mortality trends in men and women with diabetes, 1971 to 2000. Ann Intern Med. 2007;147:149-155.
8. Huxley R, Barzi F, Woodward M. Excess risk of fatal coronary heart disease associated with diabetes in men and women: meta-analysis of 37 prospective cohort studies. BMJ. 2006;332:73-78.
9. Ferrara A, Mangione CM, Kim C, et al. Sex disparities in control and treatment of modifiable cardiovascular disease risk factors among patients with diabetes: Translating Research Into Action for Diabetes (TRIAD) Study. Diabetes Care. 2008;31:69-74.
10. Gouni-Berthold I, Berthold HK, Mantzoros CS, B?hm M, Krone W. Sex disparities in the treatment and control of cardiovascular risk factors in type 2 diabetes. Diabetes Care. 2008;31:1389-1391.

This communication on the importance of home blood pressure monitoring is supported by Omron Healthcare, Inc. It is intended to help pharmacists and their staff understand the importance of home blood pressure monitoring.