The effect of clinical features and glucocorticoids on biopsy findings in giant cell arteritis

Table 4 Potential predictors at time of diagnosis^a for positive temporal artery biopsy in patients with GCA

Feature	Odds ratio	95 % CI	p
Sex (female vs male)	2.01	0.97–4.20	0.06
Age (per year)	1.00	0.96–1.04	0.94
Time from glucocorticoid treatment to TAB (per day)	1.02	0.95–1.09	0.65
Current smoking vs non-current smoking^b	0.74	0.35–1.56	0.43
Ever smoking vs never smoking^b	0.90	0.36–2.28	0.83
ESR (per mm/h)	1.02	1.00–1.03	0.04
CRP (per mg/l)	1.01	1.00-1.02	0.01
Time from glucocorticoid treatment to TAB
< 1 day^c	2.86	1.06–7.70	0.04
1–3 days	1.00 (reference)
4–6 days	1.70	0.70–4.13	0.24
7–28 days	1.80	0.54–6.00	0.34
ESR (mm/h) ^* ^b
Quartile 1 (20–61)	1.00 (reference)
Quartile 2 (62–79)	0.45	0.17-1.20	0.11
Quartile 3 (80–99)	1.14	0.43-3.01	0.80
Quartile 4 (100–150)	4.27	1.09-16.82	0.04
CRP (mg/l) ^** ^b
Quartile 1 (4–56)	1.00 (reference)
Quartile 2 (57–98)	2.89	0.94-8.86	0.06
Quartile 3 (99–142)	4.64	1.33-16.23	0.02
Quartile 4 (143–478)	2.39	0.81-7.04	0.12

TAB temporal artery biopsy, ESR erythrocyte sedimentation rate, CRP C-reactive protein, CI confidence interval
^* p for trend 0.01
^** p for trend 0.07
^aDefined as the day when a tentative clinical diagnosis was made and glucocorticoid treatment was started
^bAvailable data: ESR from 171 patients; CRP 136 patients; current smoking at diagnosis 98 patients; ever smoking 135 patients.
^cIncludes individuals biopsied before start of glucocorticoid treatment

ISSN: 1471-2474