In Africa, the prevalence of hypertension among individuals living with diabetes is alarmingly high, with an overall rate of 58.1%. Central Africa recorded the highest prevalence at 77.6%, followed by Southern Africa at 69.1%. Risk factors that increase the likelihood of developing hypertension in individuals living with diabetes include older age, obesity, urban living, male gender, and longer diabetes duration.²

Understanding the link between diabetes and hypertension

Understanding the interconnectedness between diabetes and hypertension is essential for effective management. Hypertension in diabetes is driven by factors such as maladaptive autonomic nervous system changes, immune dysfunction, and increased activation of the renin-angiotensin-aldosterone system (RAAS).¹

Additionally, obesity, exacerbated by sedentary lifestyles and excessive caloric intake, worsens insulin resistance, leading to oxidative stress, inflammation, and endothelial dysfunction, all of which contribute to persistent high blood pressure (BP).¹

Increased sodium intake also plays a significant role in the pathogenesis of hypertension. Sodium retention leads to increased blood volume and arterial pressure, and in individuals with CKD, the kidney's compensatory mechanisms often fail, worsening hypertension.¹

Furthermore, premature vascular ageing and dysregulation of the autonomic nervous system, characterized by increased sympathetic activity, further exacerbate hypertension in individuals living with diabetes.¹

BP targets in T2DM patients

Managing hypertension is a critical aspect of diabetes care, as rigorous BP control can significantly reduce the risk of diabetes-related complications. The 2024 American Diabetes Association (ADA) guidelines emphasize individualizing BP targets for patients with diabetes and hypertension through a shared decision-making process.³

This approach should consider the patient’s CV risk, potential adverse effects of antihypertensive medications, and personal preferences. For most patients, a BP target of <130/80mmHg is recommended, provided it can be safely achieved.³

For pregnant women with diabetes and chronic hypertension, initiating or adjusting therapy at a BP threshold of 140/90mmHg has been associated with better pregnancy outcomes without increasing the risk of small-for-gestational-age births.³

Conversely, for those with BP readings <90/60mmHg, treatment should be deintensified. A target range of 110–135/85mmHg is suggested to reduce the risk of accelerated maternal hypertension.³

Lifestyle and pharmacologic interventions

For individuals with BP >120/80mmHg, the ADA recommends lifestyle interventions, including weight loss when necessary, adopting a Dietary Approaches to Stop Hypertension or DASH eating pattern, reducing sodium, increasing potassium intake, moderating alcohol consumption, quitting smoking, and increasing physical activity.³

Pharmacologic therapy is recommended for patients with confirmed BP readings of ≥130/80mmHg, with the goal of achieving BP <130/80mmHg. For individuals with BP ≥150/90mmHg, combination therapy or single-pill combinations should be initiated promptly, along with lifestyle modifications.³

The first-line treatment is typically an angiotensin-converting enzyme inhibitor (ACEi) or an angiotensin receptor blocker (ARB). Patients with a urinary albumin-to-creatinine ratio ≥300mg/g, or between 30mg/g–299mg/g, should be treated with an ACEi or ARB at the maximum tolerated dose.³

If one class of medication is not well tolerated, substitution with the other is recommended. Patients on these treatments should have their serum creatinine, estimated glomerular filtration rate, and potassium levels monitored within seven- to 14-days of initiation and at least annually thereafter.³

Keep in mind that the pathophysiology of hypertension in individuals of African descent differs from other ethnic groups, often requiring tailored antihypertensive strategies. The initial recommended treatment includes a thiazide-like diuretic or a calcium channel blocker (CCB), such as amlodipine.^4,5

Antihypertensive therapy choices

Telmisartan, an ARB, is widely preferred for managing hypertension in individuals with diabetes due to its unique ability to prevent CVD progression. Studies have shown that telmisartan monotherapy effectively lowers BP and improves metabolic parameters in individuals living with T2DM, including those with or without complications.^6,7,8

However, combination therapy such as telmisartan and amlodipine, a dihydropyridine CCB, is often needed to meet BP targets, as timely control is crucial for reducing CV risk. Telmisartan/amlodipine lower BP through complementary mechanisms. Telmisartan blocks the angiotensin II type 1 receptor (AT1), reducing vasoconstriction and associated adverse effects such as aldosterone secretion and catecholamine release.⁸

Additionally, telmisartan acts as a partial agonist of peroxisome proliferator-activated receptor γ, improving glucose tolerance and lipid metabolism. Amlodipine, on the other hand, inhibits calcium influx in smooth muscle cells, promoting vasodilation and reducing peripheral resistance.⁸

The Telmisartan and Amlodipine Single-pill Combinations vs Amlodipine Monotherapy for Superior Blood Pressure Lowering and Improved Tolerability in Patients with Uncontrolled Hypertension (TEAMSTA-5) study, which included participants with T2DM, showed significantly greater BP reductions with the combination therapy, along with higher goal rates for SBP and DBP compared to amlodipine alone. Importantly, peripheral oedema, a common side effect of amlodipine, was less frequent in the combination therapy group.⁹

The TEAMSTA-10 study, which also included participants living with T2DM, evaluated patients who failed to achieve DBP control with amlodipine alone. The results confirmed that telmisartan/amlodipine combinations significantly outperformed amlodipine monotherapy. These studies underscore the efficacy of combining telmisartan and amlodipine in achieving BP control and reducing CV risk in patients with T2DM.¹⁰

Conclusion

The management of hypertension in individuals living with T2DM is complex but essential for reducing the risk of CVD, CKD, and other complications. Evidence supports the use of combination therapies such as telmisartan and amlodipine for achieving optimal BP control in this population. Individualized treatment plans, incorporating lifestyle changes and pharmacologic interventions, are key to improving outcomes for patients with T2DM and hypertension.

References

1. Naha S, Gardner MJ, Khangura D, et al. Hypertension in Diabetes. [Updated 2021 Aug 7]. In: Feingold KR, Anawalt B, Blackman MR, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK279027/
2. Hinneh T, Akyirem S, Bossman IF, et al. Regional prevalence of hypertension among people diagnosed with diabetes in Africa, a systematic review and meta-analysis. PLOS Glob Public Health, 2023.
3. American Diabetes Association. Cardiovascular Disease and Risk Management: Standards of Care in Diabetes - 2024. Diabetes Care, 2024.
4. Kempegowda P, Chandan JS, Abdulrahman S, et al. Managing hypertension in people of African origin with diabetes: Evaluation of adherence to NICE Guidelines. Prim Care Diabetes, 2019.
5. Passarella P, Kiseleva TA, Valeeva FV, Gosmanov AR. Hypertension Management in Diabetes: 2018 Update. Diabetes Spectr, 2018.
6. Gadge P, Gadge R, Paralkar N, Jain P, Tanna V. Effect of telmisartan on blood pressure in patients of type 2 diabetes with or without complications. Perspect Clin Res, 2018.
7. Sharma AM,  Bakris G, Neutel JM, et al. Single-Pill Combination of Telmisartan/Amlodipine Versus Amlodipine Monotherapy in Diabetic Hypertensive Patients: An 8-Week Randomized, Parallel-Group, Double-Blind Trial. Clinical Therapeutics, 2012.
8. Billecke SS, Marcovitz PA. Long-term safety and efficacy of telmisartan/amlodipine single pill combination in the treatment of hypertension. Vascular Health and Risk Management, 2013.
9. Neldam S, Lang M, Jones R et al, on behalf of the TEAMSTA-5 Investigators. Telmisartan and amlodipine single-pill combinations vs amlodipine monotherapy for superior blood pressure lowering and improved tolerability in patients with uncontrolled hypertension: results of the TEAMSTA-5 study. J Clin Hypertens (Greenwich), 2011.
10. Neldam S, Edwards C, Jones R, et al, on behalf of the TEAMSTA-10 Investigators. Switching patients with uncontrolled hypertension on amlodipine 10 mg to single-pill combinations of telmisartan and amlodipine: results of the TEAMSTA-10 study. Curr Med Res Opin, 2011.