Multivariable linear regression model: relationship between HbA1c(%) and the presence of individual conditions (prevalence >1%) in participants with type 2 diabetes (T2D)
| Predictor variables | Prevalence N(%) | Non-adjusted | Adjusted* | ||||
| Mean difference in HbA1c (SE) | 95% CI | P value | Mean difference in HbA1c (SE) | 95% CI | P value | ||
| Concordant conditions | |||||||
| T2D only (reference) | |||||||
| Hypertension | 42 812 (61.4) | 0.01 (0.01) | −0.01 to 0.03 | 0.364 | 0.01 (0.01) | −0.01 to 0.03 | 0.336 |
| Coronary heart disease | 11 953 (17.1) | 0.03 (0.02) | 0.00 to 0.06 | 0.022 | 0.03 (0.01) | 0.00 to 0.05 | 0.040 |
| Chronic kidney disease | 5919 (8.5) | 0.01 (0.02) | −0.03 to 0.05 | 0.745 | −0.01 (0.02) | −0.05 to 0.02 | 0.456 |
| Atrial fibrillation | 5318 (7.3) | 0.01 (0.02) | −0.03 to 0.05 | 0.567 | 0.00 (0.02) | −0.04 to 0.04 | 0.907 |
| Stroke/TIA | 4730 (6.8) | −0.01 (0.02) | −0.05 to 0.03 | 0.692 | 0.00 (0.02) | −0.42 to 0.04 | 0.919 |
| Heart failure | 4410 (6.3) | 0.02 (0.02) | −0.02 to 0.07 | 0.333 | 0.01 (0.02) | −0.03 to 0.05 | 0.622 |
| Diabetic retinopathy | 2266 (3.3) | −0.02 (0.03) | −0.08 to 0.04 | 0.547 | 0.00 (0.03) | −0.06 to 0.06 | 0.996 |
| Peripheral vascular disease | 1945 (2.8) | 0.05 (0.03) | −0.02 to 0.11 | 0.151 | 0.02 (0.03) | −0.05 to 0.08 | 0.509 |
| Diabetic neuropathy | 1117 (1.6) | −0.01 (0.04) | −0.10 to 0.07 | 0.763 | 0.01 (0.04) | −0.07 to 0.09 | 0.892 |
| Discordant conditions | |||||||
| T2D only (reference) | |||||||
| Painful conditions | 38 645 (55.4) | 0.01 (0.01) | −0.04 to 0.01 | 0.211 | −0.02 (0.01) | −0.04 to 0.00 | 0.122 |
| Dyspepsia | 22 022 (31.6) | 0.00 (0.01) | −0.02 to 0.02 | 0.954 | 0.00 (0.01) | −0.02 to 0.03 | 0.746 |
| Depression | 15 926 (22.8) | 0.00 (0.01) | −0.03 to 0.80 | 0.801 | −0.01 (0.01) | −0.03 to 0.02 | 0.600 |
| Anxiety | 14 262 (20.5) | 0.00 (0.01) | −0.02 to 0.03 | 0.772 | −0.01 (0.01) | −0.03 to 0.02 | 0.621 |
| Psoriasis/eczema | 14 037 (20.1) | 0.02 (0.01) | −0.01 to 0.04 | 0.193 | 0.02 (0.01) | −0.01 to 0.04 | 0.130 |
| Cancer | 12 733 (18.3) | 0.01 (0.01) | −0.01 to 0.04 | 0.319 | 0.00 (0.01) | −0.02 to 0.03 | 0.704 |
| Asthma | 10 276 (14.7) | −0.01 (0.02) | −0.04 to 0.02 | 0.412 | −0.02 (0.01) | −0.05 to 0.01 | 0.219 |
| Thyroid disorders | 7613 (10.9) | 0.02 (0.02) | −0.02 to 0.05 | 0.309 | 0.00 (0.02) | −0.03 to 0.03 | 0.961 |
| Diverticular disease | 6039 (8.7) | 0.02 (0.19) | −0.02 to 0.06 | 0.279 | 0.02 (0.02) | −0.02 to 0.05 | 0.366 |
| COPD | 5521 (7.9) | 0.02 (0.02) | −0.02 to 0.06 | 0.315 | 0.02 (0.02) | −0.02 to 0.06 | 0.273 |
| Constipation | 5162 (7.4) | 0.02 (0.02) | −0.02 to 0.06 | 0.339 | 0.01 (0.02) | −0.03 to 0.05 | 0.524 |
| Chronic liver disease | 4864 (7.0) | 0.03 (0.02) | −0.01 to 0.08 | 0.129 | 0.02 (0.02) | −0.02 to 0.06 | 0.222 |
| Osteoporosis | 4567 (6.6) | 0.00 (0.02) | −0.04 to 0.05 | 0.882 | 0.01 (0.02) | −0.03 to 0.05 | 0.761 |
| Glaucoma | 3102 (4.5) | 0.05 (0.03) | 0.00 to 0.11 | 0.038 | 0.03 (0.02) | −0.02 to 0.08 | 0.235 |
| Rheumatoid arthritis and other connective tissue disorders | 2643 (3.8) | −0.01 (0.03) | −0.06 to 0.05 | 0.8 | 0.01 (0.03) | −0.04 to 0.07 | 0.597 |
| Migraine | 2622 (3.8) | −0.03 (0.03) | −0.09 to 0.03 | 0.305 | −0.01 (0.03) | −0.07 to 0.04 | 0.575 |
| Dementia | 2247 (3.2) | 0.05 (0.03) | −0.01 to 0.11 | 0.09 | 0.03 (0.03) | −0.02 to 0.09 | 0.255 |
| Schizophrenia/ bipolar disorder | 2198 (3.2) | −0.01 (0.03) | −0.08 to 0.05 | 0.655 | −0.01 (0.03) | −0.07 to 0.05 | 0.694 |
| Irritable bowel syndrome | 1540 (2.2) | −0.01 (0.04) | −0.08 to 0.06 | 0.756 | −0.01 (0.03) | −0.08 to 0.05 | 0.676 |
| Alcohol problem | 1447 (2.1) | 0.00 (0.04) | −0.07 to 0.08 | 0.96 | 0.00 (0.04) | −0.07 to 0.07 | 0.974 |
| Viral hepatitis | 815 (1.2) | 0.02 (0.05) | −0.08 to 0.12 | 0.689 | 0.04 (0.05) | −0.05 to 0.13 | 0.393 |
| Epilepsy | 754 (1.1) | 0.09 (0.05) | −0.02 to 0.19 | 0.108 | 0.08 (0.05) | −0.01 to 0.18 | 0.082 |
*Adjusting for age, sex, SEIFA, smoking status, and number of diabetes medication. All covariates were treated as fixed effects and the general practice as a random effect to allow for the correlation of HbA1c within each practice.
COPD, chronic obstructive pulmonary disease; HbA1c, glycated haemoglobin; TIA, transient ischaemic attack.