• Sanjay K Gupta
  • Surendra H Bodakhe


Pulse pressure (PP) is a predictor and major risk factor for cardiovascular (CV) diseases as left ventricular hypertrophy, myocardial infarction, carotid hypertrophy, atherosclerosis, congestive heart failure and stroke as well as chronic renal failure progression. PP has been proved a strong forecaster of CV risk, particularly when it is higher than 60 mm Hg and more strongly relates to carotid hypertrophy and extent of atherosclerosis than systolic pressure. Isolated systolic hypertension (ISH) is common among the elderly and is accompanied by elevated pulse pressure. However, treatment of ISH may further raise the PP if diastolic pressure is lowered to a greater extent than systolic pressure. Several drugs for hypertension have the side effect of increasing resting PP irreversibly, other antihypertensive drugs, such as ACE inhibitors, have been shown to lower the PP. Various approaches made by researchers for the maintenance of normal PP to reduce the mortality caused due to CV events based on the abnormal PP. We briefly review the therapeutic consequences for the attenuation of elevated PP associated with various CV events


Pulse pressure, Cardiovascular diseases, Arterial stiffness, Antihypertensive therapy


Matricciani LA, Paquet C, Howard NJ et al. Investigating individual and area-level socioeconomic gradients of pulse pressure among normotensive and hypertensive participants. Int J Environ Res Public Health. 2013;10:571-589.

Liaw SY, Scherpbier A, Klainin-Yobas P, Rethans JJ. A review of educational strategies to improve nurses' roles in recognizing and responding to deteriorating patients. Int Nurs Rev. 2011;58(3):296-303.

O'Rourke M, Frohlich ED. Pulse pressure: Is this a clinically useful risk factor? Hypertension. 1999;34:372-374.

Klabunde RE. A textbook of Cardiovascular Physiology Conceptsâ€. 2nd edition, published by Lippincott Williams & Wilkins. 2011.

Pahlevan NM, Gharib M. Low pulse pressure with high pulsatile external left ventricular power: influence of aortic waves. J Biomech. 2011;44(11):2083-2089.

Wilkinson IB, MacCallum H, Flint L, Cockcroft JR, Newby DE, Webb DJ. The influence of heart rate on augmentation index and central arterial pressure in humans. J Physiol. 2000;65:263-270.

Luc MAB, Bortel V, Harry AJ, Struijker-Boudier, Safar ME. Pulse Pressure, Arterial Stiffness, and Drug Treatment of Hypertension. Hypertension. 2001;38:914-921.

Franklin SS, Khan SA, Wong ND, Larson MG, Levy D. Is pulse pressure useful in predicting risk for coronary heart disease: The Framingham Heart Study. Circulation. 1999;100:354-360.

Dart AM, Kingwell BA. Pulse pressure--a review of mechanisms and clinical relevance. J Am Coll Cardiol. 2001 Mar 15;37(4):975-84.

Leslie R, Buckley JP. Low pulse pressure does not reduce the efficacy of a heart failure exercise programme. Br J Cardiol. 2012;19:30-33.

Yildiran T, Koc M, Bozkurt A, Sahin DY, Unal I, Acarturk E. Low pulse pressure as a predictor of death in patients with mild to advanced heart failure. Tex Heart Inst J. 2010;37(3):284–290.

Weiss A, Boaz M, Beloosesky Y, Kornowski R, Grossman E. Pulse pressure predicts mortality in elderly patients. J Gen Intern Med. 2009;24(8):893-896.

Glasser SP, Krasikov T, Devereux RB et al. Subclinical, hemodynamic, and echocardiographic abnormalities of high pulse pressure in hypertensive and non-hypertensive adults. Am J Cardiovasc Dis. 2012;2(4):309-317.

Franklin SS, Gustin W 4th, Wong ND, et al. Hemodynamic patterns of age-related changes in blood pressure. The Framingham Heart Study. Circulation. 1997; 96:308.

Steppan J, Barodka V, Berkowitz DE, Nyhan D. Vascular stiffness and increased pulse pressure in the aging cardiovascular system. Cardiol Res Pract. 2011; 2011:263585.

García-Palmieriemail M, Crespoemail C, Mc Gee D, Sempos C, Smit E, Sorlie P. Wide pulse pressure is an independent predictor of cardiovascular mortality in Puerto Rican men. Nutr Metab Cardiovasc Dis. 2005;15:71-78.

Dheaa K, Al-Omerm B. The impact of antihypertensive medication class on pulse pressure. Thi-Qar Med J. 2010;4(1):18-25.

Cameron JD, Jennings GL, Dart AM. Systemic arterial compliance is decreased in newly-diagnosed patients with coronary heart disease: implications for prediction of risk. J Cardiovasc Risk. 1996;3(6):495–500.

Kelly RP, Tunin R, Kass DA. Effect of reduced aortic compliance on cardiac efficiency and contractile function of in situ canine left ventricle. Circ Res. 1992;71(3):490-502.

Alfie J, Waisman GD, Galarza CR, Camera MI. Contribution of stroke volume to the change in pulse pressure pattern with age. Hypertension. 1999;34(4 Pt 2):808-12.

Avolio A, Jones D, Tafazzoli-Shadpour M. Quantification of alterations in structure and function of elastin in the arterial media. Hypertension. 1998;32(1):170-175.

Abhayaratna WP, Srikusalanukul W, Budge MM. Aortic stiffness for the detection of preclinical left ventricular diastolic dysfunction: pulse wave velocity versus pulse pressure. J Hypertens. 2008;26(4):758-764.

Blacher J, Guerin AP, Pannier B, Marchais SJ, Safar ME, London GM. Impact of aortic stiffness on survival in endstage renal disease. Circulation 1999;99(18):2434-2439.

Nichols WW. Clinical measurement of arterial stiffness obtained from noninvasive pressure waveforms. Am J Hypertens. 2005;18:3S-10S.

Cecelja M, Jiang B, Spector TD, Chowienczyk P. Progression of central pulse pressure over 1 decade of aging and its reversal by nitroglycerin. Journal of the American College of Cardiology. 2012;59(5):475–483.

Lokaj P, Parenica J, Goldbergova MP, Helanová K, Miklik R, Kubena P, Parenicova I, Jarkovsky J, Littnerova S, Vasku A, Spinar J. Pulse pressure in clinical practice. Eur J Cardiovasc Med. 2011;2(1):66-68.

Blyth KG, Syyed R, Chalmers J et al. Pulmonary arterial pulse pressure and mortality in pulmonary arterial hypertension. Respir Med. 2007;101(12):2495-2501.

Glynn RJ, Chae CU, Guralnik JM, Taylor JO, Hennekens CH. Pulse pressure and mortality in older people. Arch Intern Med. 2000;160:2765-2772.

Safar ME, Levy BI, Struijker-Boudier H. Current perspectives on arterial stiffness and pulse pressure in hypertension and cardiovascular diseases. Circulation. 2003;107:2864-2869.

Panagiotakos D, Kromhout D, Menotti A et al. The relation between pulse pressure and cardiovascular mortality in 12,763 middle-aged men from various parts of the world: A 25-year follow-up of the seven countries study. Arch Intern Med. 2005;165:2142-2147.

Pannier B, Brunei P, Aroussy WE, Lacolley P, Safar ME. Pulse pressure and echocardiographic findings in essential hypertension. J Hypertens.1989;7:127-132.

Christensen KL. Reducing Pulse Pressure in Hypertension May Normalize Small Artery Structure. Hypertension. 1991;18:722-727.

Cosson E, Herisse M, Laude D, Thomas F, Valensi P, Attali JR, Safar ME, Dabire H. Aortic stiffness and pulse pressure amplification in Wistar-Kyoto and spontaneously hypertensive rats. Am J Physiol Heart Circ Physiol. 2007;292:H2506–H2512.

Nichols WW, O’Rourke MF. McDonald’s Blood Flow in Arteries. Theoretical, Experimental and Clinical Principles. 4th edition. London: Edward Arnold, 1998.

Nikolov NM, Fontes ML, White WD et al. Pulse Pressure and Long-Term Survival after Coronary Artery Bypass Graft Surgery. Anesth Analg. 2010;110:335-340.

Vaccarino V, Holford TR, Krumholz HM. Pulse pressure and risk for myocardial infarction and heart failure in the elderly. J Am Coll Cardiol. 2000;36:130-138.

Benetos A, Thomas F, Joly L, Blacher J, Pannier B, Labat C. Pulse pressure amplification: a mechanical biomarker of cardiovascular risk. J Am Coll Cardiol. 2010;55:1033-1037.

Chae CU, Pfeffer MA, Glynn RJ, Mitchell GF, Taylor JO, Henekens CH. Increased pulse pressure and risk of heart failure in the elderly. JAMA. 1999;281:634-639.

Jovanovic D, Jovovic D, Mihailovic-Stanojevic N et al. Effect of carvedilol on pulse pressure and left ventricular hypertrophy in spontaneously hypertensive rats with adriamycin nephropathy. Biomed Pharmacother. 2009;63(8):571-576.

Mitchell GF, Izzo JL Jr, Lacourcière Y et al. Omapatrilat reduces pulse pressure and proximal aortic stiffness in patients with systolic hypertension: results of the conduit hemodynamics of omapatrilat international research study. Circulation. 2002;105(25):2955-2961.

Avanzini F, Alli C, Boccanelli A et al. High pulse pressure and low mean arterial pressure: two predictors of death after a myocardial infarction. J Hypertens. 2006;24(12):2377-2385.

Fang J, Madhavan S, Cohen H, Alderman MH. Measure of blood pressure and myocardial infarction in treated hypertensive patients. J Hypertens. 1995;13;413-419.

Gopal M, Karnath B. Clinical diagnosis of heart failure. Hospital Physician. 2009;45(7):9-15.

Alfie J, Galarza C, Waisman G. Noninvasive hemodynamic assessment of the effect of mean arterial pressure on the amplitude of pulse pressure. American Journal of Hypertension. 2005;18:60S–64S.

Wan Z, Liu X, Wang X et al. small artery elasticity predicts future cardiovascular events in chinese patients with angiographic coronary artery disease. Angiology. 2013 Feb 20.

Jacobs L, Buczynska A, Walgraeve C et al. Acute changes in pulse pressure in relation to constituents of particulate air pollution in elderly persons. Environmental Res. 2012;117:60–67.

Nawrot T, Den Hond E, Thijs L, Staessen JA. Isolated systolic hypertension and the risk of vascular disease. Curr Hypertens Rep. 2003;5:372–379.

Stoner L, Young JM, Fryer S. Assessments of arterial stiffness and endothelial function using PulseWave Analysis. Int J Vasc Med. 2012;1-9.

Vlachopoulos C, Aznaouridis K, O’Rourke MF, Safar ME, Baou K, Stefanadis C. Prediction of cardiovascular events and all-cause mortality with central haemodynamics: a systematic review and meta-analysis. Eur Heart J. 2010;31(15):1865-1871.

Williams B, Lacy PS, Thom SM et al. Differential impact of blood pressure-lowering drugs on central aortic pressure and clinical outcomes: principal results of the Conduit Artery Function Evaluation (CAFE) study. Circulation. 2006;113(9):1213-1225.

Vlachopoulos C, O’Rourke M. Genesis of the normal and abnormal arterial pulse. Curr Probl Cardiol. 2000;25(5):303-367.

Chowienczyk PJ, Kelly RP, MacCallum H et al. Photoplethysmographic assessment of pulse wave reflection: blunted response to endothelium-dependent beta2-adrenergic vasodilation in type II diabetes mellitus. Journal of the American College of Cardiology. 1999;34(7):2007–2014.

Briet M, Boutouyrie P, Laurent S, London GM. Arterial stiffness and pulse pressure in CKD and ESRD. Kidney Int. 2012;82:388–400.

Pierce GL, Zhu H, Darracott K et al. Arterial stiffness and pulse-pressure amplification in overweight/obese African- American adolescents: relation with higher systolic and pulse pressure. Am J Hypertens. 2013;26(1):20-26.

Benetos A, Adamopoulus C, Bureau JM et al. Determinants of accelerated progression of arterial stiffness in normotensive subjects and in treated hypertensive subjects over a six period. Circulation. 2002;105:1202-1207.

Fang W, Yang X, Bargman JM, Oreopoulos DG. Association between pulse pressure and mortality in patients undergoing peritoneal dialysis. Perit Dial Int. 2009;29(2):163-170.

Nation DA, Delano-Wood L, Bangen KJ et al. Antemortem pulse pressure elevation predicts cerebrovascular disease in autopsy-confirmed alzheimer's disease. J Alzheimers Dis. 2012;30(3):595-603.

Loutzenhiser R, Bidani A, Chilton L. Renal myogenic response-kinetic attributes and physiologic role. Circulation Res. 2002;90:1316-1324.

Loutzenhiser R, Griffin K, Williamson G, Bidani A. Renal Autoregulation: New perspectives regarding the protective and regulatory roles of the underlying mechanisms. Am J Physiol Regul Integr Comp Physiol. 2006;290:R1153-R1167.

Ford ML, Tomlinson LA, Chapman TP, Rajkumar C, Holt SG. Aortic stiffness is independently associated with rate of renal function decline in chronic kidney disease stages 3 and 4. Hypertension. 2010;55:1110-1115.

Mimran A. Consequence of elevated pulse pressure on renal function. J Hypertens. 2006;24(3):S3-S7.

Guntheroth WG. Increased Pulse Pressure Causes Vascular Injury in Pulmonary and Systemic Arteries. Decreasing the Pulsatility with Banding and Vasodilators Can Stabilize Pulmonary Hypertension. J Clinic Experiment Cardiol. 2010;1(2):1-4.

Koumaras C, Tzimou M, Stavrinou E, Griva T, Gossios TD, Katsiki N, Athyros VG, Mikhailidis DP, Karagiannis A. Role of antihypertensive drugs in arterial 'de-stiffening' and central pulsatile hemodynamics. Am J Cardiovasc Drugs. 2012;12(3):143-156.

Doonan RJ, Hausvater A, Scallan C, Mikhailidis DP, Pilote L, Daskalopoulou SS. The effect of smoking on arterial stiffness. Hypertens Res. 2010;33(5):398-410.

Nestel P, Shige H, Pomeroy S, Cehun M, Abbey M, Raederstorff D. The n-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid increase systemic arterial compliance in humans. Am J Clin Nutr. 2002;76(2):326-330.

van der Schouw YT, Pijpe A, Lebrun CE et al. Higher usual dietary intake of phytoestrogens is associated with lower aortic stiffness in postmenopausal women. Arterioscler Thromb Vasc Biol. 2002;22(8):1316-1322.

Sacks FM, Svetkey LP, Vollmer WM et al. Effects on blood pressure of reduced dietary sodium and the Dietary Approaches to Stop Hypertension (DASH) diet. DASH Sodium Collaborative Research Group. N Engl J Med. 2001;344(1):3–10.

Cameron JD, Dart AM. Exercise training increases total systemic arterial compliance in humans. Am J Physiol. 1994;266(2):H693-H701.

Sierksma A, Lebrun CE, van der Schouw YT. Alcohol consumption in relation to aortic stiffness and aortic wave reflections: a cross-sectional study in healthy postmenopausal women. Arterioscler Thromb Vasc Biol.2004;24(2):342–348.

Sierksma A, Muller M, van der Schouw YT, Grobbee DE, Hendriks HF, Bots ML. Alcohol consumption and arterial stiffness in men. J Hypertens. 2004;22(2):357–362.

Topouchian J, Brisac AM, Pannier B, Vicaut E, Safar M, Asmar R. Assessment of the acute arterial effects of converting enzyme inhibition in essential hypertension: a double-blind, comparative and crossover study. J Hum Hypertens. 1998;12:181-7.

Benetos A, Santoni JP, Safar ME. Vascular effects of intravenous infusion of the angiotensin-converting enzyme inhibitor perindoprilat. J Hypertens. 1990;8;819-826.

Stergiou GS, Efstathiou SP, Skeva II, Baibas NM, Kalkana CB, Mountokalakis TD. Assessment of drug effects on blood pressure and pulse pressure using clinic, home and ambulatory measurements. J Hum Hypertens. 2002;16(10):729-735.

O'Rourke MF. Arterial mechanics and wave reflection with antihypertensive therapy. J Hypertens. 1992;10:S43-S49.

Klemsdal TO, Moan A, Kjeldsen SE. Effects of selective angiotensin II type 1 receptor blockade with losartan on arterial compliance in patients with mild essential hypertension. Blood Press. 1999;8:214-219.

Kost CK Jr, Li P, Jackson EK. Blood pressure after captopril withdrawal from spontaneously hypertensive rats. Hypertension. 1995;25(1):82-87.

Hayashi K, Miyagawa K, Sato K, Ueda R, Dohi Y. Temocapril, an angiotensin converting enzyme inhibitor, ameliorates age-related increase in carotid arterial stiffness in normotensive subjects. Cardiology. 2006;106(3):190-194.

Asmar RG, London GM, O´Rourke ME, Safar ME. REASON Project Coordinators and Investigators: Improvement in blood pressure, arterial stiffness and wave reflections with a very-low-dose perindopril/indapamide combination in hypertensive patient: a comparison with atenolol. Hypertension. 2001 Oct;38(4): 922-926.

Tsoucaris D, Benetos A, Legrand M, London GM, Safar ME. Proximal and distal pulse pressure after acute antihypertensive vasodilating drugs in Wistar-Kyoto and spontaneously hypertensive rats. J Hypertens. 1995;13(2):243-249.

Miller KE. Antihypertensive medication in elderly: An analysis. Am Fam Physician. 2004;70(1):194.

Frimodt-Møller M, Kamper AL, Strandgaard S, Kreiner S, Nielsen AH. Beneficial effects on arterial stiffness and pulse-wave reflection of combined enalapril and candesartan in chronic kidney disease randomized trial. PLoS One. 2012;7(7):e41757.

Benetos A, Vasmant D, Thiery P, Safar M. Effect of ramipril on arterial hemodynamics. J Cardiovasc Pharmacol. 1991;18:S153-S156.

Amar J, Ruidavets JB, Peyrieux JC et al. C-reactive protein elevation predicts pulse pressure reduction in hypertensive subjects. Hypertension. 2005;46(1):151-155.

Ichihara A, Hayashi M, Kaneshiro Y, Takemitsu T, Homma K, Kanno Y, Yoshizawa M, Furukawa T, Takenaka T, Saruta T. Low doses of losartan and trandolapril improve arterial stiffness in hemodialysis patients. Am J Kidney Dis. 2005;45(5):866-874.

Suzuki H, Nakamoto H, Okada H, Sugahara S, Kanno Y: A selective angiotensin receptor antagonist, valsartan, produced regression of left ventricular hypertrophy associ associated with a reduction of arterial stiffness. Adv Perit Dial. 2003;19:59-66.

Jiang XJ, O'Rourke MF, Zhang YQ, He XY, Liu LS. Superior effect of an angiotensin-converting enzyme inhibitor over a diuretic for reducing aortic systolic pressure. J Hypertens. 2007;25(5):1095-1099.

Giles TD, Robinson TD. Effects of olmesartan medoxomil on systolic blood pressure and pulse pressure in the management of hypertension. Am J Hypertens. 2004;17:690-695.

Mahmud A, Feely J. Effect of angiotensin-II receptor blockade on arterial stiffness: beyond blood pressure reduction. Am J Hypertens. 2002;15:1092-1095.

Ting CT, Chou CY, Chang MS, Wang SP, Chiang BN, Yin FC. Arterial hemodynamics in human hypertension: effect of adrenergic blockade. Circulation. 1991;84:1049-1057.

Chen JM, Heran BS, Perez MI, et al. Blood pressure lowering efficacy of beta blockers as second-line therapy for primary hypertension. Cochrane Database Syst Rev. 2010; 1:CD007185.

Chen JM, Heran BS, Wright JM, et al. Blood pressure lowering efficacy of diuretics as second-line therapy for primary hypertension. Cochrane Database Syst Rev 2009; 4:CD007187.

Prisadă OV, Covic A, Arghiri E, Cernomaz A, Ungureanu G. Pulse pressure, arterial compliance and Buckberg index in hypertensive patients treated with nebivolol and nitrates. Rev Med Chir Soc Med Nat Iasi. 2007;111(2):352-357.

Polónia J, Barbosa L, Silva JA, Bertoquini S. Different patterns of peripheral versus central blood pressure in hypertensive patients treated with β-blockers either with or without vasodilator properties or with angiotensin receptor blockers. Blood Press Monit. 2010;15(5):235-239.

Suzuki H, Nakamoto H, Okada H, Sugahara S, Kanno Y: A selective angiotensin receptor antagonist, valsartan, produced regression of left ventricular hypertrophy associated with a reduction of arterial stiffness. Adv Perit Dial. 2003;19:59-66.

Kjeldsen SE, Dahlof B, Devereux RB, Julius S, Aurup P, Edelman J. Losartan Intervention for Endpoint Reduction (LIFE) Study Group: Effects of losartan on cardiovascular morbidity and mortality in patients with isolated systolic hypertension and left ventricular hypertrophy: a Losartan Intervention for Endpoint Reduction (LIFE) substudy. J Am Med Assoc. 2002;288:1491-1498.

Williams B, Lacy PS, Cruickshank JK, Collier D, Hughes AD, Stanton A, Thom S, Thurston H; CAFE and ASCOT Investigators: Impact of statin therapy on central aortic pressures and hemodynamics: principal results of the Conduit Artery Function Evaluation-Lipid-Lowering Arm (CAFE-LLA) Study. Circulation. 2009;119(1):53-61.

Asmar RG, Benetos A, Chaouche-Teyara K, Raveau-Landon CM, Safar ME. Comparison of effect of felodipine versus hydrochlorthiazide on arterial diameter and pulse wave velocity in essential hypertension. Am J Cardiol. 1993;72:794-798.

De Cesaris R, Ranieri G, Filliti V, Andriani A. Large artery compliance in essential hypertension. Effect of calcium antagonism and beta-blocking. Am J Hypertens. 1992;5:624-628.

Morgan T, Lauri J, Bertram D, Anderson A. Effect of different antihypertensive drug classes on central aortic pressure. Am J Hypertens. 2004;17(2):118-123.

Koffi I, Safar ME, Labat C, Lacolley P, Benetos A, Mourad JJ. Arterial structural changes with verapamil in spontaneously hypertensive rats. Am J Hypertens. 1999;12:732-738.

Chen CH, Nakayama M, Talbot M et al. Verapamil acutely reduces ventricular-vascular stiffening and improves aerobic exercise performance in elderly individuals. J Am Coll Cardiol. 1999;33(6):1602-1609.

Chang JJ, Luchsinger JA, Shea S. Antihypertensive medication class and pulse pressure in the elderly: analysis based on the third National Health and Nutrition Examination Survey. Am J Med. 2003;115(7):536-542.

Cushman WC, Materson BJ, Williams DW, Reda DJ. Pulse pressure changes with six classes of antihypertensive agents in a randomized, controlled trial. Hypertension. 2001;38:953-957.

Konin C, Adoh M, Adoubi A et al. Pulse pressure monitoring in hypertensive black Africans. Cardiovasc J Afr. 2012;23(1):1-6.

Starmans-Kool MJ, Kleinjans HA, Lustermans FA, Kragten JA, Breed JG, Van Bortel LM. Treatment of elderly patients with isolated systolic hypertension with isosorbide dinitrate in an asymmetric dosing schedule. J Hum Hypertens. 1998;12(8):557-561.

Stokes GS, Bune AJ, Huon N, Barin ES. Long-term effectiveness of extended-release nitrate for the treatment of systolic hypertension. Hypertension. 2005;45(3):380-384.

Stokes GS. Nitrates as adjunct hypertensive treatment. Curr Hypertens Rep. 2006;8(1):60-68.

Fitchett DH, Simkus GJ, Beaudry JP, Marpole DGF. Reflected pressure waves in the ascending aorta: effect of glyceryl trinitrate. Cardiovasc Res. 1988;22(7):494-500.

Munakata M, Nunokawa T, Yoshinaga K, Toyota T. The brachial-ankle pulse wave velocity a better predictor of pulse pressure than augmentation index in older hypertensives. JMAJ. 2005;48(5):224-233.

Williams C, Kingwell BA, Burke K, McPherson J, Dart AM. Folic acid supplementation for 3 wk reduces pulse pressure and large artery stiffness independent of MTHFR genotype. Am J Clin Nutr. 2005;82(1):26-31.

Vlachopoulos C, Hirata K, O’Rourke MF. Effect of sildenafil on arterial stiffness and wave reflection. Vasc Med. 2003;8(4):243-248.



How to Cite

Gupta, S. K., and S. H. Bodakhe. “AN ELEVATED PULSE PRESSURE: A MAJOR RISK FACTOR FOR CARDIOVASCULAR DISEASES”. Asian Journal of Pharmaceutical and Clinical Research, vol. 6, no. 9, Nov. 2013, pp. 5-11,