中国P站

Type 2 Diabetes Mellitus (T2DM) and hypertension are key risk factors for cardiovascular disease. About 60-70% patients with T2DM have hypertension, which increase the risk of stroke, cardiovascular events and all-cause mortality [1]. Recent guidelines [2,3] emphasized intensive blood pressure lowering in high-risk patients with hypertension, such as those with T2DM. The JNC 7 [4] recommended that patients with T2DM should begin antihypertensive therapy when their systolic Blood Pressure (BP) were 130 mmHg or higher and the target of BP lowering should below 130 mmHg. Majority of clinical trials [5] shown that active antihypertensive therapy reduced cardiovascular outcomes, however, what extent BP should be lowered in patients with T2DM is still in debate. The ABCD study [6] found with the target of approximately 128/75 mmHg, intensive BP control in normotensive T2DM patients decreased the progression of diabetic retinopathy and diminished the incidence of stroke. However, the ACCORD study [7] demonstrated that as compared with less than 140 mmHg, targeting a systolic BP of less than 120 mmHg did not reduce the rate of cardiovascular events. The SPRINT study [8], which recruited 9,361 patients with high cardiovascular risk hypertension but without diabetes or stroke, found that patients with a target systolic BP of less than 120 mmHg had lower rates of major cardiovascular events and all-cause mortality and greater benefits than those with a target systolic BP of less than 140 mmHg. Some professors conducted an interesting pooled analysis [9] from ACCORD and SPRINT studies that showed intensive BP lowering might decrease cardiovascular events in both patients with and without T2DM. Similar research conclusion was also demonstrated by STEP study, which aimed to provide evidences for intensive BP lowering of elder population. It’s worth noting that these studies were conducted using clinical office BP or unattended office BP that were not on behalf of real BP levels in daily life.

Home Blood Pressure Monitoring (HBPM) was measured by each individual in the usual environment. So, using HBPM may diagnose masked hypertension and devoid a white-coat effect in most patients [2]. Another strength of HBPM is that it could improve adherence to antihypertensive therapy so that to control BP well. However, most guidelines do not specify a target BP for HBPM, especially in highrisk hypertensive patients. The Japanese guidelines for hypertension recommend <125/75 mmHg as a target BP for hypertensive patients with T2DM. Compared with office BP, the method of HBPM is more complicated, some people who are anxious or have limited mobility cannot make it by themselves. The main limitations of HBPM are seldom clinical trials on HBPM-guide treatment and outcomes, which also may be the most important reason for the choice of office BP in previous and current studies.

We all know that appropriate BP has a protective effect on target organs such as heart, brain and kidneys, but excessive intensification of BP lowering could reduce blood flow to those pivotal organs. Also, hypotension leads to a decrease in coronary artery blood, which may explain the occurrence of adverse events. So, what is the optimal target BP for patients with T2DM/prediabetes?

In later issue of this journal Kazuo and colleagues reported aggressive blood pressure lowering therapy guided by HBPM improved Target Organ Damage (TOD) in hypertensive patients with T2DM/prediabetes. In this study, 60 patients with uncontrolled hypertension and T2DM/prediabetes were treated with different antihypertensive drugs according to a titration schedule for target home level less than or equal to 125/75 mmHg. They recorded the clinic, home, and ambulatory BP measures for evaluating BP levels and four indicators for assessing TOD at baseline and six months. The results showed that compared with baseline, all BP levels were lower and all indicators of TOD were improved in the six months. Besides, some indicators of TOD were associated with the changes in BP measures. Overall, this study confirmed that hypertensive patients with T2DM/prediabetes could achieve and benefit from a BP target of 125/75 mmHg measured by HBPM. These findings do not seem to be consistent with the previous ACCORD study. However, in the newly published ESPRIT study, the intensive BP lowering treatment with systolic BP of less than 120 mmHg prevented major vascular events as compared with those of less than 140 mmHg for high cardiovascular risk hypertensive patients, regardless of diabetes or stroke. But, several important issues remained unanswered which deserved our attention.

The first question which we are interested in is about the best BP criteria for patients with diabetes. There is no doubt that those patients should control their BP below 140/90 mmHg, but recent and previous studies seem have reported contradictory findings on whether these patients’ BP needs to fall further. Although Kazuo and colleagues attempted to demonstrate the benefit of under 125/75 mmHg for target organs, only thirty percent of patients achieved target systolic and diastolic BP. So, more biological evidences and larger clinical trials are needed to confirm the optimal BP in patients with T2DM. Besides, about twenty-two percent of participants in this study had adverse effects related to intensive BP lowering, which is a bit high and might be considered when looking for the most appropriate target BP for patients with T2DM. Another concern is whether office BP is representative of the true optimal BP for patients with T2DM. At present, more and more evidences show that compared with HBPM and ABPM, office BP is more limited. And which indicators of HBPM or ABPM are more suitable for evaluating the prognosis of cardiovascular diseases needs further investigation.

The study by Kazuo and colleagues provided some evidence for patients with T2DM/prediabetes in intensive BP lowering when BP values were guided by HBPM. At the same time, they need further find suitable target BP and measurements for those high-risk patients.

1. Nilsson PM, Cederholm J, Zethelius BR (2011) . Blood Press 20: 348-354.

   [] [] []

2. Mancia G, Kreutz R, Brunström M (2023) 2023 ESH Guidelines for the management of arterial hypertension the task force for the management of arterial hypertension of the European Society of Hypertension: Endorsed by the International Society of Hypertension (ISH) and the European Renal Association (ERA). J Hypertens 41: 1874-2071.
3. Al-Makki A, DiPette D, Whelton PK (2022) . Hypertension 79: 293-301.

   [] [] []

4. Chobanian AV, Bakris GL, Black HR (2003) JAMA 289: 2560-2572.

   [] [] []

5. Xie X, Atkins E, Lv J (2016) . Lancet 387: 435-443.

   [] [] []

6. Schrier RW, Estacio RO, Esler A (2002) . Kidney Int 61: 1086-1097.

   [] [] []

7. Cushman WC, Evans GW, Byington RP (2010) N Engl J Med 362: 1575-1585.

   [] [] []

8. Lewis CE, Fine LJ, Beddhu S (2021) N Engl J Med 384: 1921-1930.

   [] [] []

9. Brouwer TF, Vehmeijer JT, Kalkman DN (2018) Diabetes Care 41: 1142-1148.

   [] [] []