Analysis of real patient data suggests that diabetic patients who used insulin had an increased risk of major osteoporosis and hip fractures compared to metformin users.
The study results, which are based on data from more than 6,500 patients, indicate that the risk of major osteoporotic fracture nearly doubled and the risk of hip fracture more than tripled in patients using insulin, but these associations were attenuated in diabetic patients who used a combination of metformin and insulin therapy.
“Patients using insulin or sulfonylureas have an elevated risk of fractures compared to users of metformin alone, and the risk may be higher in non-obese, well-controlled diabetic patients,” said Sung Hye Kong, MD. , from Seoul National University Hospital. in South Korea, in a press release.
As patients age, the threat to quality of life and life expectancy posed by fractures increases in unison, especially for patients with diabetes. Although observational data suggest that patients with diabetes were at increased risk of fracture, little is known about the influence of different antidiabetic treatment regimens on this risk. With this in mind, Kong, along with a team of colleagues from Seoul National University Hospital and Seoul National University Medical School, sought to compare fracture risk in diabetic patients using different classes of drugs. compared to those using metformin.
Using the Common Data Model database from 2008 to 2012, researchers identified a cohort of 6,694 patients aged 50 and older who used the same diabetes medications for more than a year to include them. in their analyses. This cohort had a mean age of 65.8 years, 47.7% were women, and the median duration of follow-up was 6.1 years. Overall, the incidence rates for major osteoporotic fractures and hip fractures in this cohort were 8.36 and 1.53 per 1000 person-years, respectively.
For analysis, patients were grouped according to their medication use. These groups were defined as metformin alone, insulin alone, sulfonylurea alone, dipeptidyl-4-inhibitor (DPP4i) plus metformin, insulin plus metformin, sulfonylurea plus insulin, sulfonylurea plus metformin, DPP4i with sulfonylurea and insulin, and sulfonylurea with insulin and metformin . The primary outcomes of interest were the risks of major osteoporotic fracture and the risk of hip fractures in each group, which were assessed using Cox proportional hazards models, with the metformin group serving as the cohort of reference. The investigators noted that these models were adjusted for several factors, including age, sex, BMI, HbA1c, fracture history, secondary osteoporosis, rheumatoid arthritis, cardiovascular disease, cerebrovascular disease, dementia, chronic kidney disease, and use of steroids, proton pump inhibitors, or warfarin.
After analysis, the results indicated that insulin users had a higher risk of major osteoporotic fractures (HR, 1.96 [95% CI, 1.28-3.02]) and hip fracture (HR, 3.06 [95% CI, 1.21-7.77) compared to metformin users in fully adjusted models. However, further analysis demonstrated this increase in risk became insignificant when assessing use of insulin plus metformin for risk of both major osteoporotic fractures (HR, 1.32 [95% CI, 0.77-2.27]) and hip fractures (HR, 2.68 [95% CI, 0.56-12.8)]) in the same models. In subgroup analyses, results suggest that insulin users observed a significantly higher risk of major osteoporotic fracture in insulin users compared to metformin-only users in patients with HbA1c greater than 7 % or a BMI greater than 25 kg/m2.
“From real-world data using the Common Data Model, we found that insulin users had an elevated risk of major osteoporosis and hip fracture compared to metformin users, which was attenuated in users of a combination of insulin and metformin,” Kong said.
This study, “Increased fracture risk in patients using insulin compared to metformin, attenuated in patients using a combination of insulin and metformin: based on common data models”, was presented at ENDO 2022.