Intramuscular Corticosteroid Therapy in the Treatment of Alopecia Areata: A Time-to-Event Analysis

Figures & data

Table 1 Demographic and Clinical Characteristics of Participants with Alopecia Areata

Variables	N = 101
Sex, n (%)
● Male	31 (30.7)
● Female	70 (69.3)
Age at AA onset, year, mean ± SD	40.4 ± 12.6
Age at AA onset, year, n (%)
● ≤40 years	50 (49.5)
● >40 years	51 (50.5)
Duration of disease, month, median (IQR)	2 (1–4)
Duration of disease, n (%)
● ≤6 months	77 (76.2)
● >6 months	24 (23.8)
AA subtype, n (%)
● Patch AA	20 (19.8)
● Multiple AA	46 (45.5)
● Diffuse AA	16 (15.8)
● AT	9 (8.9)
● AU	5 (5.0)
● Ophiasis	5 (5.0)
Severity of AA (SALT score), n (%)
● 0–25%	11 (10.9)
● 26–50%	16 (15.8)
● 51–75%	60 (59.4)
● 76–100%	14 (13.9)
Body hair involvement, n (%)	6 (5.9)
Nail involvement, n (%)	9 (8.9)
Comorbidity, n (%)
● Atopy	2 (1.9)
● Autoimmune thyroid diseases	6 (5.9)
Family history of AA, n (%)	2 (1.9)

Abbreviations: AA, alopecia areata; AT, alopecia totalis; AU, alopecia universalis; IQR, interquartile range; SALT, Severity of Alopecia Tool; SD, standard deviation.

Table 2 Treatment Outcomes of Intramuscular Corticosteroid Therapy in Participants with Alopecia Areata

Treatment Outcomes	N = 101
Treatment failure (<10% regrowth)
● Incidence, n (%)	3 (2.9)
Initial hair regrowth (25% regrowth)
● Cumulative incidence, n (%)	86 (85.1)
● Incidence rate, person-year (CI)	64.0 (51.9–79.3)
● Median time to achieve endpoint, month (CI)	0.9 (0.8–1.2)
● Median cumulative dose to achieve endpoint, mg	100
● Cumulative dose to achieve endpoint, mg, median (IQR)	80 (20–160)
Significant hair regrowth (75% regrowth)
● Cumulative incidence, n (%)	81 (80.2)
● Incidence rate, person-year (CI)	17.0 (13.6–21.7)
● Median time to achieve endpoint, month (CI)	3.4 (2.9–4.4)
● Median cumulative dose to achieve endpoint, mg	200
● Cumulative dose to achieve endpoint, mg, median (IQR)	120 (40–200)
Complete hair regrowth (100% regrowth)
● Cumulative incidence, n (%)	49 (48.5)
● Incidence rate, person-year (CI)	8.0 (6.2–10.9)
● Median time to achieve endpoint, month (CI)	6.1 (5.1–8.1)
● Cumulative dose to achieve endpoint, mg, median (IQR)	160 (60–240)
Relapse
● Cumulative incidence, n (%)	48 (47.5)
● Incidence rate, person-year (CI)	5.5 (4.2–7.3)
● Median time to relapse, month (CI)	11.3 (8.6–15.4)

Abbreviations: CI, confidence interval; IQR, interquartile range.

Figure 1 Kaplan–Meier curve demonstrating (A) the cumulative incidence of patients achieving significant hair regrowth (75% regrowth); (B) the cumulative corticosteroid dose of patients achieving significant hair regrowth; (C) the cumulative incidence of patients achieving significant hair regrowth of four groups according to baseline Severity of Alopecia Tool (SALT) score; and (D) the cumulative incidence of patients with relapse.

Table 3 Univariate and Multivariable Analyses for the Factor Associated with Significant Hair Regrowth After Intramuscular Corticosteroid Therapy in Patients with Alopecia Areata

Variables	HR (95% CI)	P-value	Adjusted HR (95% CI)	P-value
Female	2.39 (1.09–4.61)	0.035*	1.13 (0.81–5.91)	0.086
Age at AA onset	1.02 (0.89–1.06)	0.423
Age group at AA onset
● ≤40 years	Reference
● >40 years	2.45 (1.49–3.69)	0.046*	1.68 (0.92–3.42)	0.187
Duration of disease >6 months	0.63 (0.25–1.49)	0.141
AA subtype
● Patch AA	Reference
● Multiple AA	1.34 (0.25–2.92)	0.182
● Diffuse AA	2.63 (0.99–4.61)	0.062
● AT	0.82 (0.29–2.85)	0.845
● AU	0.16 (0.09–3.15)	0.753
● Ophiasis	0.76 (0.09–2.92)	0.911
Severity of AA (SALT score)
● 0–25%	Reference
● 26–50%	0.56 (0.32–2.09)	0.186
● 51–75%	0.64 (0.31–2.67)	0.823
● 76–100%	1.49 (0.81–3.68)	0.595
Body hair involvement	0.67 (0.03–4.28)	0.745
Nail involvement	0.26 (0.08–0.69)	0.036*	0.04 (0.01–0.55)	0.015*
Atopy	0.68 (0.13–5.16)	0.621
Autoimmune thyroid diseases	1.91 (0.83–3.28)	0.142
Family history of AA	0.96 (0.41–3.56)	0.363

Note: *Statistically significant.

Abbreviations: AA, alopecia areata; AT, alopecia totalis; AU, alopecia universalis; CI, confidence interval; HR, hazard ratio; SALT, Severity of Alopecia Tool.

Table 4 Univariate and Multivariable Analyses for the Factor Associated with Relapse After Intramuscular Corticosteroid Therapy in Patients with Alopecia Areata

Variables	HR (95% CI)	P-value	Adjusted HR (95% CI)	P-value
Female	1.15 (0.64–1.69)	0.536
Age at AA onset	1.01 (0.99–1.06)	0.104
Age group at AA onset
● ≤40 years	Reference
● >40 years	1.55 (0.78–2.56)	0.151
Duration of disease >6 months	3.12 (1.36–4.94)	0.016*	4.02 (1.52–4.66)	0.005*
AA subtype
● Patch AA	Reference
● Multiple AA	0.94 (0.66–2.67)	0.723
● Diffuse AA	0.85 (0.39–3.62)	0.264
● AT	3.12 (0.79–5.64)	0.459
● AU	2.92 (0.59–3.95)	0.644
● Ophiasis	1.49 (0.08–3.12)	0.814
Severity of AA (SALT score)
● 0–25%	Reference
● 26–50%	0.91 (0.72–2.19)	0.135
● 51–75%	1.14 (0.51–2.67)	0.718
● 76–100%	0.69 (0.29–1.89)	0.653
Body hair involvement	1.05 (0.29–3.18)	0.425
Nail involvement	2.78 (0.98–4.09)	0.812
Atopy	1.34 (0.63–3.89)	0.291
Autoimmune thyroid diseases	2.39 (1.42–5.14)	0.041*	2.71 (0.82–4.65)	0.069
Family history of AA	1.76 (0.87–2.88)	0.635

Note: *Statistically significant.

Abbreviations: AA, alopecia areata; AT, alopecia totalis; AU, alopecia universalis; CI, confidence interval; HR, hazard ratio; SALT, Severity of Alopecia Tool.