Outcomes following hip and knee replacement in diabetic versus nondiabetic patients and well versus poorly controlled diabetic patients: a prospective cohort study

Figures & data

Figure 1. Directed acyclic graph depicting the potential associations underlying the effect of the main exposures on the outcomes.

U: unmeasured dietary habits and sedentary lifestyle factors.

Exposure: diabetes mellitus or HbA1c status.

Outcome: patient reported, clinical or complication outcomes.

Table 2. Sample characteristics by diabetic status at preoperative assessment. Values are number (percentage) unless otherwise stated

	Total sample	Nondiabetic patients	Diabetic patients
	n = 587	n = 523	n = 64
Trial intervention
Injection	294 (50)	263 (50)	31 (48)
Standard care	293 (50)	260 (50)	33 (52)
Primary total joint replacement
Hip	300 (51)	276 (53)	24 (37)
Knee	287 (49)	247 (47)	40 (63)
Age, mean (SD)	68 (10)	68 (10)	70 (8)
Sex
Female	325 (55)	295 (56)	30 (47)
Male	262 (45)	228 (44)	34 (53)
BMI, mean (SD)	31 (6)	31 (6)	34 (6)
≤ 30	303 (52)	282 (54)	21 (33)
> 30	284 (48)	241 (46)	43 (67)
EQ VAS^a, n	553	492	61
mean (SD)	66 (20)	66 (20)	64 (19)
EQ-5D Score^b, n	555	495	60
mean (SD)	0.42 (0.32)	0.43 (0.32)	0.37 (0.31)
FCI^c (Number of comorbidities)
	192 (33)	178 (34)	14 (22)
2	168 (29)	156 (30)	12 (19)
3	115 (20)	102 (19)	13 (20)
	112 (19)	87 (17)	25 (39)
HADS^d Total, n	567	505	62
mean (SD)	13 (7)	13 (7)	13 (6)
WOMAC^e Pain, n	587	523	64
mean (SD)	42 (17)	43 (18)	41 (15)
WOMAC Function, n	558	499	59
mean (SD)	44 (18)	44 (18)	43 (16)
WOMAC Stiffness, n	548	487	61
mean (SD)	44 (22)	43 (22)	44 (18)
WOMAC Total, n	537	479	58
mean (SD)	44 (17)	44 (17)	44 (14)

a EQ visual analogue scale (0–100, worst to best health state).

b EQ-5D 3L descriptive system.

c Modified Functional Co-morbidity Index without BMI and diabetes diagnoses (categorized sum of the 16 remaining diagnoses).

d Hospital Anxiety and Depression Scale with anxiety and depression scores combined (0–42, best to worst distress state).

e Western Ontario and McMaster Universities Osteoarthritis Index (0–100 worst to best pain, function, stiffness or total score).