Table 2:
Results of the piecewise linear mixed effects model examining effects of DKA at diagnosis of diabetes and other risk factors on HbA1c levels over time
| Variable | Model 1 Estimate (SE) |
p-value | Model 2 Estimate (SE) |
p-value |
|---|---|---|---|---|
| Age at Diagnosis (per 1 year) | −0.01 (0.008) | 0.24 | −0.01 (0.008) | 0.91 |
| Sex (female vs male) | 0.11 (0.06) | 0.08 | 0.12 (0.06) | 0.05 |
| Race/Ethnicity | ||||
| Non-Hispanic white | Ref | − | Ref | − |
| Non-Hispanic black | 0.72 (0.12) | <.0001 | 0.78 (0.12) | <.0001 |
| Hispanic | 0.31 (0.12) | 0.01 | 0.35 (0.12) | 0.005 |
| Other | 0.20 (0.23) | 0.38 | 0.19 (0.23) | 0.40 |
| Household Income | ||||
| <$25K | Ref | − | Ref | − |
| $25-49K | −0.04 (0.12) | 0.74 | −0.05 (0.12) | 0.69 |
| $50-74K | −0.02 (0.14) | 0.90 | −0.05 (0.13) | 0.70 |
| $75K+ | −0.32 (0.13) | 0.02 | −0.35 (0.13) | 0.01 |
| Insurance Status | ||||
| Private | Ref | − | Ref | − |
| Medicaid/Medicare | 0.35 (0.12) | 0.004 | 0.32 (0.12) | 0.007 |
| Self-pay | 0.17 (0.28) | 0.54 | 0.26 (0.29) | 0.37 |
| Other | −0.07 (0.24) | 0.79 | −0.05 (0.24) | 0.85 |
| Insulin Regimen (time varying) | ||||
| Injectable Insulin | Ref | − | Ref | − |
| Pump | −0.16 (0.07) | 0.01 | −0.15 (0.07) | 0.02 |
| Frequency of Glucose Monitoring (time varying) | ||||
| 4 or more times a day | Ref | − | Ref | − |
| 1-3 times a day | 0.49 (0.06) | <.0001 | 0.49 (0.06) | <.0001 |
| Less than once a day | 0.93 (0.20) | <.0001 | 0.94 (0.20) | <.0001 |
| Baseline Fasting C-Peptide (per ng/mL) | − | − | −0.18 (0.05) | <.0001 |
| Rate of Change per Year in HbA1c <1 Year Diabetes Duration | ||||
| DKA Status (yes vs no) | −1.31 (0.81) | 0.11 | −1.33 (0.80) | 0.09 |
| Rate of Change per Year in HbA1c 1+ Years Diabetes Duration | ||||
| DKA Status (yes vs no) | 0.18 (0.01) | <.0001 | 0.16 (0.02) | <.0001 |
A linear mixed effects model examining the relationship between DKA status at baseline and change in HbA1c levels over the 9 year study. Models were additionally adjusted for duration of diabetes at baseline visit and study site. Model 1 unadjusted for baseline fasting C-peptide. Model 2 adjusted for baseline fasting C-peptide level. DKA = diabetic ketoacidosis; HbA1c = hemoglobin A1c; SE = standard error; T1D = type 1 diabetes.