Mortality among people with a history of diabetes, stroke, or myocardial infarction was similar for each condition, results from a large prospective study suggest. In addition, having two or all three of these conditions was associated with a reduced life expectancy of 12 and 15 years, respectively.
“Valid estimation of the associations of cardiometabolic multimorbidity with mortality requires comparison of people with multimorbidity with participants within the same cohorts who do not have any of the conditions at baseline,” authors of the Emerging Risk Factors Collaboration reported. The study was published online July 7 in JAMA. “Few population cohorts have had sufficient power-detail, and longevity to enable such comparisons,” the researchers wrote. “Our results highlight the need to balance the primary prevention and secondary prevention of cardiovascular disease.”
In an effort to estimate the associations of cardiometabolic multimorbidity with mortality and reductions in life expectancy, the researchers analyzed individual participant data in the Emerging Risk Factors Collaboration (ERFC) from 689,300 participants recruited between 1960 and 2007 into 91 prospective cohorts that have recorded mortality during prolonged follow-up. They compared the ERFC results with those from the UK Biobank, a prospective cohort study of 499,808 patients recruited between 2006 and 2010.
At baseline, the mean age of the ERFC participants was 53 years, 51% were women, and most were enrolled in Europe (69%) or North America (24%). Among ERFC participants without a history of diabetes, stroke, or MI, the all-cause mortality adjusted to the age of 60 years was 6.8 per 1,000 person-years. After adjustment for age and gender, mortality was 15.6 per 1,000 person-years among participants with a history of diabetes, 16.1 among those with stroke, 16.8 among those with an MI, 32 among those with a history of both diabetes and MI, 32.5 among those with both diabetes and stroke, 32.8 among those with both stroke and MI, and 59.5 among those with diabetes, stroke, and MI.
When translated into hazard ratios for mortality, and compared with the reference group, the age- and gender-adjusted HR was 1.9 for participants with a history of diabetes, 2.1 among those with stroke, 2.0 among those with MI, 3.7 among those with a history of both diabetes and MI, 3.8 among those with both diabetes and stroke, 3.5 among those with a both stroke and MI, and 6.9 among those with diabetes, stroke, and MI.
The hazard ratios in all categories were similar to those found in the UK Biobank.
“Our results suggest that the estimated reductions in life expectancy associated with cardiometabolic multimorbidity are of similar magnitude to those previously noted for exposures of major concern to public health, such as lifelong smoking (10 years of reduced life expectancy) and infection with the human immunodeficiency virus (11 years of reduced life expectancy),” the authors wrote. “For example, cardiometabolic multimorbidity at the age of 60 years was associated with an average reduction in life expectancy of about 15 years. We estimated even greater reductions in life expectancy in patients with multimorbidity at younger ages, such as 23 years of life lost in patients with 3 conditions at the age of 40 years.”
The ERFC authors disclosed numerous relevant financial ties to industry.