Alcohol raises blood pressure in people with Type 2 Diabetes
New research shows that even drinking moderate amounts of alcohol is associated with high blood pressure in people with Type 2 Diabetes
It is well established that heavy drinking raises blood pressure, but the effect of moderate alcohol consumption is less clear and has not been well studied in people with Type 2 Diabetes. A new study known as The ACCORD (Action to Control Cardiovascular Risk in Diabetes) Trial has shown that even moderate drinking can raise blood pressure in people with Type 2 Diabetes, raising the risk of serious complications including heart attacks and stroke.
The researchers, based in the United States, analysed data from more than 10,000 people to see if high blood pressure was more common with higher alcohol intakes. The participants were split into groups according to how much alcohol they consumed, as reported in a questionnaire: none, light (1–7 drinks per week), moderate (8–14 drinks per week) and heavy (≥15 drinks/week). Their alcohol intake was then compared to their blood pressure.
The results, published this September in the Journal of the American Heart Association (JAHA), showed that:
- Light alcohol consumption was not associated with raised blood pressure.
- Moderate alcohol consumption was associated with raised blood pressure and stage 1 and 2 hypertension.
- Heavy alcohol consumption was associated with raised blood pressure and stage 1 and 2 hypertension. It approximately trebled the risk of stage 2 hypertension – defined as blood pressure of 140/90mmHg or higher for those not taking medicines, or 130mmHg for those taking medicines.
There was a dose response relationship, which means the higher the alcohol intake, the greater the effect on blood pressure.
Type 2 Diabetes raises the risks of cardiovascular diseases (diseases of the heart and blood vessels) such as heart disease, heart attacks and strokes. High blood pressure is also a major cause of these diseases, so having the two together is a particular problem.
Although the link between heavy drinking and raised blood pressure is well known, the relationship between light and moderate alcohol drinking and blood pressure has not been clear in the scientific research and there is indication that light and moderate drinking could be beneficial. However, two recent metanalyses (studies which pool the data from all relevant studies) have shown a linear relationship – meaning blood pressure rises with the amount of alcohol consumed. The effects on people with diabetes specifically have not previously been studied.
The authors of this study stated: “Although prior research has not demonstrated an association of moderate alcohol consumption with hypertension, we show in a large cohort that moderate alcohol consumption is associated with hypertension in patients with Type 2 Diabetes Mellitus and elevated cardiovascular risk.”
They add that the findings shed light on a modifiable risk factor for which clinicians can counsel patients. Namely, alcohol consumption is something people can change to improve their own health, providing an opportunity to prevent life-changing events such as heart attacks and strokes.
The study has some limitations and it is important to consider the results within these limitations. For example, alcohol intake was self-reported and participants were also at higher risk of cardiovascular disease due to other causes.
Nirmala Markandu, Hypertension Nurse Specialist at Blood Pressure UK, explains:
“Alcohol is linked to many preventable diseases as it affects the body in numerous ways, so everyone should try to stick to the recommended limits. This study suggests that limiting alcohol is particularly important if you have Type 2 Diabetes, as it can raise your blood pressure which can in turn raise your risk of life-changing events.
There is no safe limit for how much alcohol you can drink, but the UK Government recommends drinking no more than 14 units per week, for both men and women, this should keep you below the amounts linked to raised blood pressure in this study.