Table 5

Association of various risk factors with incident hypersensitivity reactions in patients who received allopurinol

	Multivariable adjusted (allopurinol dose)		Multivariable adjusted (duration of allopurinol use)
	HR (95% CI)	P value	HR (95% CI)	P value
Age (years)
65 to <75	Ref		Ref
75 to <85	1.09 (0.97 to 1.23)	0.16	1.08 (0.95 to 1.21)	0.24
≥85	0.93 (0.78 to 1.12)	0.44	0.90 (0.76 to 1.08)	0.26
Sex
Male	Ref		Ref
Female	1.32 (1.17 to 1.48)	< 0.0001	1.29 (1.15 to 1.45)	< 0.0001
Race
White	Ref		Ref
Black	0.95 (0.80 to 1.14)	0.59	0.94 (0.78 to 1.12)	0.46
Other	0.95 (0.77 to 1.16)	0.60	0.93 (0.76 to 1.14)	0.47
Select Charlson-Romano score comorbidities
Myocardial infarction	1.06 (0.74 to 1.52)	0.76	1.04 (0.72 to 1.50)	0.83
Diabetes	1.21 (1.00 to 1.45)	0.047	1.20 (1.00 to 1.44)	0.05
Malignancy	0.97 (0.83 to 1.14)	0.73	0.97 (0.83 to 1.14)	0.74
Congestive heart failure	1.21 (0.95 to 1.54)	0.12	1.21 (0.95 to 1.53)	0.12
Moderate or severe liver disease	Not estimable	N/A	Not estimable	N/A
Moderate or severe renal disease	0.90 (0.75 to 1.09)	0.27	0.87 (0.72 to 1.05)	0.14
Statins	1.03 (0.80 to 1.33)	0.81	1.03 (0.80 to 1.32)	0.84
Beta-blockers	1.09 (0.85 to 1.40)	0.50	1.09 (0.85 to 1.39)	0.52
Diuretics	1.05 (0.83 to 1.34)	0.68	1.05 (0.82 to 1.33)	0.70
ACE inhibitor	0.98 (0.73 to 1.31)	0.87	0.98 (0.73 to 1.31)	0.87
Allopurinol start dose, mg/day
Allopurinol <200	Ref		N/A
Allopurinol 200–299	1.00 (0.84 to 1.19)	1.00
Allopurinol ≥300	1.27 (1.12 to 1.44)	0.0002
Allopurinol use duration, days	N/A
1–30			Ref
31–60			0.86 (0.53 to 1.40)	0.55
61–90			1.00 (0.61 to 1.62)	0.98
91–120			0.86 (0.53 to 1.40)	0.55
>120			0.79 (0.55 to 1.12)	0.19

Multivariable-adjusted dose and duration models were examined separately using different reference categories, as applicable.
Bold font represents statistically significant comparisons with a p-value <0.05.
*Based on person day count.
N/A, not applicable; Ref, reference category.