Study looks at possible increase in heart disease among people diagnosed with diabetes after middle age.
Having diabetes has shown to increase the risk of developing cardiovascular disease, and hence early detection of prediabetes can reduce the risk of developing cardiovascular disease if measures are taken to prevent the development to diabetes through lifestyle changes and, if necessary, pharmacological therapies.
In a meta-analysis of 53 prospective cohort studies that evaluated individuals for a median follow-up duration of 9.5 years for the associations between different definitions of prediabetes and the risk of cardiovascular disease and all-cause mortality, compared with normo-glycemia, prediabetes was associated with an increased risk of composite cardiovascular disease, coronary heart disease, stroke and all-cause mortality. Increases in HBA1c to 6.5%-7.7% (39-47 mmol/mol) or 7-7.7%(42-47 mmol/mol) were both associated with an increased risk of composite cardiovascular disease and coronary heart disease, but not with an increased risk of stroke and all-cause mortality. The study concluded that prediabetes was associated with an increased risk of cardiovascular disease. The health risk might be increased in people with a fasting glucose concentration as low as 114 mg/dL (5.6 mmol/L) or HbA1c of 6.7%(39 mmol/mol.
In a recent study, scientists at Wake Forest School of Medicine sought to determine the absolute risk or probability of developing heart disease for people who were only at a prediabetes level of glucose and who had no prior cardiovascular disease event. Data was taken from seven observational studies. The sample included 19,630 patients, both white and black, male and female, who were followed from 1960 through 2015. Cardiovascular disease was defined as fatal/nonfatal coronary heart disease and fatal/nonfatal stroke. Absolute risk of cardiovascular disease was determined through analysis of participants’ fasting glucose category beginning at age 55 through 85.
The risk of cardiovascular disease by fasting glucose category at index age 55 years was estimated using a modified Kaplan-Meier survival analysis, adjusted for the competing risk of non-cardiovascular disease death. They also assessed risk for incident of cardiovascular disease according to change in fasting glucose before 50 years of age.
Risk for CVD through 85 years of age ranged from 15.3% (people without diabetes) to 38.6% (diabetes levels) among women and from 21.5% (people without diabetes) to 47.7% (diabetes levels) among men. A fasting glucose of 134 mg/dL – 151 mg/dL (6.3–6.9 mmol/L) was associated with higher long-term cardiovascular disease risk compared with the lowest fasting glucose among men, but not women. Increases in glucose during midlife with conversion to diabetes were associated with higher cardiovascular risk (1.3- to 3.6-fold) than when increasing glucose below the diabetes threshold.
Although individuals who had prediabetes levels of glucose did not have a higher absolute risk for cardiovascular disease, most people go on to develop diabetes unless they take measures to reduce their glucose levels through better diet, increased physical activity, and pharmacologic therapies as needed.
The study concluded that middle-age individuals with diabetes have high long-term absolute risk for cardiovascular disease. These data strongly support the importance of glucose monitoring in midlife for cardiovascular disease prevention.
- If patients can avoid the development of diabetes, they may be able to prevent cardiovascular disease.
- Individuals who have prediabetes levels of glucose need to be treated aggressively.
- Most people go on to develop diabetes unless they take measures to reduce their glucose levels.
Bancks MP, Ning H, Allen NB, et al. Long-term absolute risk for cardiovascular disease stratified by fasting glucose level [published online January 7, 2019]. Diabetes Care.
Huang Y, Cai X, Mai W, Li M, Hu Y. Association between prediabetes and risk of cardiovascular disease and all-cause mortality: systematic review and meta-analysis. BMJ. 2016 Nov 23;355
Dahlia Elimairi, Pharm D student at UC Denver Skaggs School of Pharmacy