Table 1.
Demographics, comorbidity and laboratory data of participants on the day of study
| Variable | Total (N = 250) | Normal cognitive performance ( n = 127) | Cognitive impairment (MoCA < 26/30) ( n = 111) | Cognitive impairment (TMT A or B) (n = 18) | Relative cognitive impairment (>1 SD below the mean Z-score on any test) (n = 62) | Significance (normal versus cognitive impairment using any measure) |
|---|---|---|---|---|---|---|
| Age (years) | 66 (53–74) | 59 (49–69) | 70 (58–77) | 77 (75–84) | 76 (67–81) | 0.000 |
| Sex, n (%) | ||||||
| Male | 164 | 81 (63.8) | 74 (66.7) | 11 (61.1) | 39 (62.9) | 0.538 |
| Ethnic group, n (%) | ||||||
| Caucasian | 241 (96.4) | 124 (97.6) | 105 (94.6) | 18 (100) | 61 (98.4) | 0.204 |
| Non-Caucasian | 9 (3.6) | 3 (2.4) | 6 (5.4) | 1 (1.6) | ||
| Employment status, n (%) | ||||||
| Full time | 82 (32.8) | 57 (44.9) | 23 (20.7) | 1 (5.6) | 5 (8.1) | |
| Part time | 20 (8.0) | 7 (5.5) | 12 (10.8) | 2 (11.1) | 6 (9.7) | |
| Homemaker | 2 (0.8) | 1 (0.8) | 1 (0.9) | 0 | 1 (1.6) | 0.006 |
| Retired | 124 (49.6) | 51 (40.2) | 65 (58.6) | 15 (83.3) | 46 (74.2) | |
| Never employed | 0 (0) | 0 (0) | 0 (0) | 0 | 0 (0) | |
| Unemployed | 6 (2.4) | 3 (2.4) | 3 (2.7) | 0 | 1 (1.6) | |
| Unable to work due to health | 12 (4.8) | 6 (4.7) | 5 (4.5) | 0 | 3 (4.8) | |
| Other | 2 (0.84) | 2 (1.6) | 2 (1.8) | 0 | 0 (0) | |
| Living alone, n (%) | ||||||
| Yes | 46 (18.4) | 20 (15.7) | 24 (21.6) | 6 (33.3) | 13 (21.0) | 0.272 |
| Marital status, n (%) | ||||||
| Married | 175 (70) | 92 (72.4) | 74 (66.7) | 12 (66.7) | 41 (66.1) | |
| Widowed | 14 (5.6) | 3 (2.4) | 10 (9) | 2 (11.1) | 6 (9.7) | |
| Separated | 4 (1.6) | 3 (2.4) | 1 (0.9) | 0 | 1 (1.6) | 0.008 |
| Single | 35 (14.0) | 19 (15.0) | 14 (12.6) | 3 (16.7) | 8 (12.9) | |
| Divorced | 10 (4) | 1 (0.8) | 9 (8.1) | 1 (5.6) | 5 (8.1) | |
| Cohabitation | 12 (4.8) | 9 (7.1) | 3 (2.7) | 0 | 1 (1.6) | |
| Education, n (%) | ||||||
| ≤12 years | 132 (52.8) | 64 (50.4) | 60 (54.1) | 12 (66.7) | 38 (61.3) | 0.439 |
| Current or previous smoker | ||||||
| Yes, n (%) | 128 (51.2) | 62 (48.8) | 60 (54.1) | 13 (72.2) | 33 (53.2) | 0.444 |
| BMI | 27.8 (24.8–31.9) | 27.4 (24.8–32.0) | 27.8 (24.1–31.7) | 25.1 (25.5–28.4) | 28.2 (25.8–31.8) | 0.897 |
| Units of alcohol/week | 0 (0–8) | 1 (0–7) | 0 (0–10) | 5 (0–2) | 0 (0–2) | 0.682 |
| Primary renal disease, n (%) | ||||||
| Diabetic nephropathy | 33 (13.2) | 15 (11.8) | 15 (13.5) | 3 (16.7) | 10 (23.3) | 0.510 |
| Renovascular | 43 (17.2) | 18 (14.2) | 22 (19.8) | 5 (27.8) | 9 (20.9) | 0.198 |
| Glomerulonephritis | 55 (22.0) | 35 (27.6) | 18 (16.2) | 3 (16.6) | 7 (16.3) | 0.031 |
| ADPKD | 32 (12.8) | 17 (13.4) | 15 (13.5) | 1 (5.6) | 3 (7.0) | 0.778 |
| Obstructive | 9 (3.6) | 4 (3.1) | 4 (3.6) | 0 | 0 (0) | 0.698 |
| Vasculitis | 10 (4.0) | 8 (6.3) | 2 (1.8) | 0 | 1 (2.3) | 0.059 |
| Pyelonephritis | 12 (4.8) | 5 (3.9) | 7 (6.3) | 1 (5.6) | 1 (2.3) | 0.517 |
| Other | 37 (14.8) | 18 (14.2) | 16 (14.4) | 3 (16.7) | 8 (18.6) | 0.777 |
| Unknown | 19 (7.6) | 7 (5.5) | 12 (10.8) | 2 (11.1) | 4 (9.3) | 0.205 |
| Psychodynamic mediations, n (%) | ||||||
| Yes | 29 (11.6) | 11 (8.7) | 17 (15.3) | 4 (22.2) | 11 (17.7) | 0.140 |
| Hypertension | 225 (90.4) | 111 (88.1) | 103 (92.8) | 15 (83.3) | 57 (91.9) | 0.220 |
| Diabetes | 60 (24) | 26 (20.5) | 31 (27.9) | 5 (27.8) | 23 (37.1) | 0.184 |
| Previous MI | 32 (12.8) | 8 (6.3) | 23 (20.7) | 4 (22.2) | 12 (19.4) | 0.002 |
| Coronary heart disease (including MI) | 57 (22.8) | 20 (15.7) | 34 (30.6) | 10 (55.6) | 22 (35.5) | 0.007 |
| Heart failure | 37 (14.9) | 10 (7.9) | 24 (21.6) | 7 (38.9) | 16 (26.2) | 0.002 |
| Atrial fibrillation | 28 (11.2) | 6 (4.7) | 18 (16.2) | 5 (27.8) | 15 (24.2) | 0.001 |
| Previous stroke | 17 (6.8) | 2 (1.6) | 14 (12.6) | 3 (16.7) | 9 (14.5) | 0.001 |
| Previous TIA | 7 (2.8) | 3 (2.4) | 3 (2.7) | 1 (5.6) | 2 (3.2) | 0.670 |
| Cerebrovascular disease (previous stroke or TIA) | 23 (9.2) | 5 (3.9) | 16 (14.4) | 3 (16.7) | 6 (14.0) | 0.003 |
| Peripheral vascular disease | 22 (8.8) | 6 (4.7) | 15 (13.5) | 2 (11.1) | 9 (14.5) | 0.013 |
| COPD | 28 (11.2) | 14 (11.0) | 13 1(1.7) | 2 (11.1) | 6 (9.7) | 0.928 |
| Depression or anxietya | 28 (12.9) | 8 (7.0) | 18 (19.1) | 3 (20) | 4 (7.4) | 0.006 |
| eGFR (mL/min/1.73 m2) | 33 (21–46) | 39 (23–50) | 29 (19–42) | 27 (18–37) | 26 (18–37) | 0.003 |
| Haemoglobin (g/L)b | 127 (114–140) | 129 (114–140) | 126 (113–137) | 114 (106–117) | 119 (111–1213) | 0.211 |
| Corrected calcium ( mmol/L)c | 2.38 (2.31–2.45) | 2.38 (2.31–2.45) | 2.39 (2.30–2.46) | 2.38 (2.30–2.43) | 2.38 (2.32–2.48) | 0.895 |
| Phosphate (mmol/L)c | 1.09 (0.95–1.27) | 1.06 (0.89–1.27) | 1.13 (0.97–1.27) | 1.21 (1.07–1.21) | 1.13 (0.98–1.23) | 0.056 |
| Parathyroid hormone ( ng/L)d | 10.4 (5.9–18.0) | 9.2 (6.0–17.2) | 11 (5.7–18.8) | 23.6 (9.4–24.5) | 12.1 (8.4–21.3) | 0.271 |
| Albumin (g/L)e | 43 (40–44) | 43 (41–45) | 43 (40–44) | 39 (38–42) | 42 (39–44) | 0.196 |
| Urine PCR (g/mol)f | 35 (10–107) | 28 (7–100) | 43 (11–100) | 150 (17–224) | 69 (17–157) | 0.052 |
| Delta eGFR (mL/min/ 1.73 m2/year)g | −1.032 (−2.844 to −0.408) | −1.23 (−3.22–0.59) | −0.77 (−2.28–0.32) | −1.10 (−1.64–0.34) | −1.02 (−2.06–0.55) | 0.574 |
| >20% drop in eGFR in 12 months prior to cognitive assessment | 26 (18.4) | 24 (23.1) | 20 (21.5) | 5 (29.4) | 11 (22.0) | 0.824 |
| >20% decline in eGFR during studyg | 109 (45.5) | 55 (47.8) | 48 (47.1) | 6 (35.3) | 27 (49.1) | 0.953 |
| >50% decline in eGFR during studyg | 34 (14.9) | 15 (14.7) | 2 (11.8) | 6 (16.2) | 6 (10.9) | 0.649 |
| Months in study | 46 (12–72) | 40 (11–68) | 49 (18–85) | 50 (18–61) | 46 (14–74) | 0.177 |
Values are presented as median (IQR) unless stated otherwise.
Psychodynamic medications included opiates, anticholinergics, benzodiazepines, antihistamines and neuropathic analgesic medications.
ADPKD, autosomal dominant polycystic kidney disease; CPOD, chronic obstructive pulmonary disease; TIA, transient ischaemic attack; PCR, protein creatinine ratio. Results based on
a
217 results,
b
249 results,
c
244 results,
d
192 results,
e
246 results,
f
247 results and
g
227 patients with >2 years of blood tests prior to cognitive test and >2 blood tests, median number of antecedent months covered by calculation was 58 months. This was based on a median of 19 (IQR 11–31) outpatient blood tests prior to the cognitive questionnaire.