Table 1.
Characteristics of PPI users and non-PPI users according to calcium supplement use
| Calcium supplement users | Non-calcium supplement users | |||||
|---|---|---|---|---|---|---|
| PPI users (n = 671) | Non-PPI users (n = 950) | p value* | PPI users (n = 892) | Non-PPI users (n = 1626) | p value* | |
| General | ||||||
| Age (mean ± SD years) | 76.2 ± 0.3 | 73.9 ± 0.3 | < 0.001 | 73.9 ± 0.25 | 72.3 ± 1.19 | < 0.001 |
| Sex (% female) | 77.8 | 83.3 | 0.006 | 58.8 | 63.3 | 0.008 |
| BMI (mean ± SD kg/m2) | 27.4 ± 0.2 | 26.27 ± 0.2 | < 0.001 | 29.6 ± 0.2 | 28.7 ± 0.1 | < 0.001 |
| Comorbidities | ||||||
| Vascular disease (%) b | 38.2 | 23.2 | < 0.001 | 45.6 | 29.1 | < 0.001 |
| Type 2 diabetes mellitus (%) c | 14.1 | 7.6 | < 0.001 | 22.5 | 16.8 | < 0.001 |
| Hypertension (%) | 65.0 | 52.8 | < 0.001 | 83.9 | 82.5 | 0.377 |
| Heart failure (%) | 8.4 | 4.1 | < 0.001 | 7.4 | 3.1 | < 0.001 |
| Biophysical and cognitive function | ||||||
| MMSE (median (IQR)) a | 28 (26–29) | 28 (26–29) | < 0.001 | 28 (26–29) | 28 (26–29) | < 0.001 |
| TUG (median (IQR) seconds) a | 15 (9–23) | 10 (8–17) | < 0.001 | 11.6 (8.6–18) | 9.7 (8–14) | < 0.001 |
| Dietary and lifestyle | ||||||
| Dairy intake (mean ± SD portion/day) | 1.31 ± 0.03 | 1.22 ± 0.03 | 0.037 | 1.10 | 1.09 | 0.63 |
| Vitamin D supplementation (%) | 97.5 | 97.7 | 0.781 | 17.9 | 20.6 | 0.11 |
| Current smoking (%) | 10.9 | 12.6 | 0.281 | 12.6 | 10.9 | 0.218 |
| Current alcohol consumption (%) | 54.8 | 62.0 | 0.003 | 54.1 | 59.4 | 0.010 |
| Medications | ||||||
| Bisphosphonate use (%) | 46.9 | 43.2 | 0.136 | 7.5 | 5.0 | 0.010 |
| Current oral glucocorticoid use (%) | 8.1 | 2.8 | < 0.001 | 1.3 | 0.9 | 0.338 |
| Thiazide diuretic (%) | 13.0 | 14.1 | 0.510 | 24.9 | 29.8 | 0.008 |
| Loop diuretic (%) | 21.2 | 9.2 | < 0.001 | 17.2 | 9.4 | < 0.001 |
| Blood results | ||||||
| Calcium (mean ± SD mmol/l) | 2.29 ± 0.00 | 2.31 ± 0.00 | < 0.001 | 2.29 ± 0.00 | 2.30 ± 0.00 | 0.011 |
| Phosphate (mean ± SD mmol/l) | 1.01 ± 0.01 | 1.01 ± 0.01 | 0.680 | 1.02 ± 0.01 | 1.02 ± 0.00 | 0.776 |
| PTH (median (IQR) pg/ml) a | 39.1 (29.8–52.5) | 33.6 (52.5–45.5) | < 0.001 | 44.7 (34.0–60.8) | 40.1 (30.9–52.6) | < 0.001 |
| PTH > 65 pg/ml (%) | 13.9 | 7.1 | < 0.001 | 20.7 | 13.4 | < 0.001 |
| 25(OH)D (mean ± SD nmol/l) | 75.5 ± 1.1 | 77.6 ± 0.9 | 0.150 | 45.2 ± 0.8 | 47.6 ± 0.6 | 0.021 |
| < 30 nmol/l (%) | 6.7 | 5.7 | 0.257 | 31.7 | 25.6 | 0.002 |
| 30–50 nmol/l (%) | 12.3 | 12.3 | 32.2 | 35.3 | ||
| 51–75 nmol/l (%) | 30.2 | 26.6 | 24.9 | 24.3 | ||
| > 75 nmol/l (%) | 50.8 | 55.3 | 11.1 | 14.7 | ||
| eGFR (mean ± SD ml/min) | 62.4 ± 0.8 | 67.6 ± 0.7 | < 0.001 | 69.3 ± 0.8 | 74.2 ± 0.6 | < 0.001 |
IQR, interquartile range; SD, standard deviation
*p value calculated χ2 for categorical variables, t-test for normally distributed continuous variables, Wilcoxon rank for non-normally distributed continuous variables. aNon-normally distributed continuous variable—other continuous variables are normally distributed. aComposite of ischaemic heart disease, previous stroke or TIA, peripheral artery disease. bComposite of self-report, consumption of diabetic medications, HBA1c ≥ 48 mmol/l