Diabetic retinopathy, kidney disease up death risk in Asians
Both diabetic retinopathy (DR) and kidney disease (DKD) increase the risk of death, although the effect of DKD is stronger, according to a recent Singapore study.
“In a population-based sample of multiethnic Asian adults, we found that (1) the presence of DR and DKD in those with diabetes was independently associated with increased risk of all-cause and cardiovascular disease (CVD) mortality; (2) risk increased with increasing severity,” said researchers, noting that there also appeared to be an additive effect between the two diabetic conditions.
Drawing from the Singapore Epidemiology of Eye Diseases study, researchers conducted a population-based cohort study on 2,964 adults (mean age 61.8±10.0 years; 49.4 percent female), of whom majority had type 2 diabetes (n=2,911; 98.2 percent). DR was present in 29.9 percent (n=862) of the participants, while 20.7 percent (n=579) had DKD. [JAMA Netw Open 2019;2:e191540]
Both DR and DKD appeared to significantly increase the risks of both all-cause and CVD deaths, which scaled with increasing disease severity. DR, for instance, was associated with at least a 50-percent greater likelihood of all-cause (hazard ratio [HR], 1.54; 95 percent CI, 1.24–1.91) and CVD (HR, 1.74; 1.27–2.40) deaths.
Associated risks with moderate (all-cause death: HR, 1.78; 1.26–2.52; CVD death: HR, 1.95; 1.20–3.19) and severe nonproliferative and proliferative DR (all-cause death: HR, 2.75; 1.93–3.92; CVD death: HR, 3.41; 2.11–5.5) were likewise strong and significant.
A similar pattern of effect was observed for DKD, but the magnitude of effect was greater in both cases (all-cause death: HR, 2.04; 1.64–2.56; CVD death: HR, 2.29; 1.64–3.19). The likelihood of all-cause (HR, 6.47; 4.65–9.01) and CVD (HR, 7.84; 4.90; 12.57) deaths were also most strongly elevated in those with estimated glomerular filtration rate <30 mL/min/1.73 m2, the highest DKD severity bracket.
There also appeared to be an additive effect between DKD and DR. Of the 2,775 participants with pertinent information, 58.9 percent had neither diabetic condition, 11.8 percent had DKD alone, 21 percent had DR alone and 8.3 had both diseases. The all-cause mortality rate in those with both diseases was 50.7 percent, higher than that in patients with neither condition (12 percent).
In comparison, mortality rate in those with either DR alone or DKD alone was 18.5 percent and 39.1 percent, respectively.
Multivariable models further confirmed these findings. The risk of all-cause (HR, 2.79; 2.05–3.72) and CVD (HR, 3.41; 2.19–5.32) mortality relative to those without either disease was significantly elevated. The same was true for those with DR alone (all-cause death: HR, 1.38; 1.03–1.86; CVD death: HR, 1.64; 1.06–2.56) or DKD alone (all-cause death: HR, 1.89; 1.40–2.57; CVD death: HR, 2.26; 1.42–3.61) but to lesser magnitudes.
“To our knowledge, this is the first study in an Asian population that assessed the association of DR and DKD with all-cause and CVD mortality,” said researchers. “Our findings suggest that regular screening of diabetic participants for DR and DKD and close monitoring and management of these conditions may reduce the risk of all-cause and CVD death in this Asian population.”