Combined poor diabetes control indicators linked to elevated risk of diabetic retinopathy, macular oedema
The combination of poor glucose control and poor blood pressure (BP) or lipid control is associated with a higher risk of developing diabetic retinopathy or diabetic macular oedema compared with poor glucose control alone in patients with type 2 diabetes (T2D), according to an Australian study.
“While glucose control remains the cornerstone of optimal diabetes management, BP control and lipid control are also important in persons with poor glucose control ... our findings reinforce this message to patients to prevent vision loss from diabetic retinopathy or macular oedema,” said the researchers.
Participants were 613 adults with T2D (mean age 66 years, 57 percent male) from the cross-sectional Australian Diabetes Management Project study, 372 and 181 of whom were diagnosed with diabetic retinopathy and diabetic macular oedema, respectively. About 18 percent of patients had good control of all three indicators.
Compared with patients with good control of all three indicators, the risk of diabetic retinopathy was elevated in patients with poor glucose control (adjusted odds ratio [adjOR], 2.44; p=0.004), poor glucose and lipid control (adjOR, 3.75; p=0.001), poor glucose and BP control (adjOR, 4.64; p<0.001), and poor glucose, BP, and lipid control (adjOR, 2.28; p=0.047). [PLoS One 2017;12:e0180252]
Findings were similar for the risk of diabetic macular oedema where the risk was elevated in those with poor glucose control (adjOR, 3.19; p=0.004), poor glucose and lipid control (adjOR, 3.60; p=0.002), poor glucose and BP control (adjOR, 2.76; p=0.019), and poor glucose, BP, and lipid control (adjOR, 3.01; p=0.021) compared with patients with good control of all three indicators.
Poor BP or lipid control, whether individually or in combination, had no effect on the risk of diabetic retinopathy or diabetic macular oedema. The risk of either condition also did not increase with the rising number of poor control indicators, which the researchers suggested could be due to the small number of participants with poor control of all three indicators or that having a higher risk profile meant that the conditions could have been detected earlier.
“[P]oor glucose control remains the most important risk factor for both diabetic retinopathy and diabetic macular oedema,” said the researchers.
“Our study suggests that while poor BP control or poor lipid control on their own do not greatly increase the risk of [diabetic retinopathy], they amplify the risk when combined with poor glucose control. These findings support the current guidelines that suggest a multifactorial systemic management plan for people with diabetes is needed to manage [diabetic retinopathy and diabetic macular oedema],” they said.
The researchers cautioned that causality could not be determined in this study, and that the findings may not extend to the entire population with diabetes.