Table 2.

Keloids associated with osteoporosis stratified by age, gender and comorbidities

Variables	Patients with keloid			Patients without keloid			Compared with non-keloid
	Osteoporosis	PYs	Rate	Osteoporosis	PYs	Rate	IRR (95% CI)	Adjusted HRa (95% CI)
All	178	49,037.42	3.63	587	511,351.32	1.48	3.16 (2.67–3.74)*	2.64 (2.21–3.17)*
Gender
Men	43	18,664.24	2.30	144	193,172.89	0.75	3.09 (2.19–4.34)*	2.97 (2.04–4.33)*
Women	135	30,373.18	4.44	443	318,178.43	1.39	3.19 (2.63–3.87)*	2.56 (2.08–3.15)*
Age
20–49	61	43,388.67	1.41	64	445,735.38	0.14	9.79 (6.89–13.90)*	7.06 (4.93–10.11)*
> 50	117	5648.75	20.71	523	65,615.94	7.97	2.59 (2.13–3.18)*	2.06 (1.67–2.54)*
Comorbidity
No	9	16,842.54	0.53	40	279,314.00	0.14	3.73 (1.81–7.69)*	4.98 (2.40–10.29)*
Yes	169	32,194.88	5.25	547	232,037.32	2.36	2.23 (1.87–2.65)*	2.54 (2.11–3.06)*

PYs Person-year; Rate, incidence rate in per 1000 person-years; IRR Incidence rate ratio in per 1000 person-years; 95% CI 95% Confidence interval; HR Hazard ratio

^a Model adjusted for age, gender, Charlson Comorbidity Index and relevant comorbidities

* P< 0.001