RESULTS

Patient’s characteristics and general data are summarized in Table 1. The two groups were comparable in terms of sex, age, skin type and family history of acne vulgaris. The total count of acne lesions decreased significantly in both groups within 8 weeks of treatment (p<0.001) (Fig. 1).

Table 1:	Demographic and other variables in the studied patients with mild-to-moderate acne vulgaris
Data are presented as mean±standard deviation or frequency (%), p<0.05 is significant

Fig. 1:	Total count of facial acne lesions in the studied groups with acne vulgaris

Fig. 2:	Percentage resolution of total facial acne lesions in the studied groups with acne vulgaris

Fig. 3:	Count of facial inflammatory acne lesions in the studied groups with acne vulgaris and oily skin

Percentage resolution of total acne lesions in both groups is shown in Fig. 2. There was no significant difference between the two groups in this regard (p = 0.17). The count of noninflammatory acne lesions decreased significantly in both groups by the end of study period (p<0.001); however, there was no significant difference between the two groups in this regard (p = 0.46). Similar trend was also present for the count of inflammatory acne lesions, which decreased significantly in both groups (p<0.001), with no significant inter-group difference (p = 0.15). Hyperpigmentation of previous acne lesions ameliorated significantly in both groups by the end of study (p<0.001), with no significant difference between the two groups (p = 0.64). No effect was seen on old scars.

Regarding complications, there was only one case (2.5%) with mild itching in the patients who received azelaic gel with alcoholic base and 2 cases (5%) with mild itching in the other group (p = 0.50). All the patients in both groups (100%) were very satisfied with the results of their treatment.

Comparing overall outcome of treatment in patients with oily and non-oily facial skin, no significant difference was found (p = 0.81). Similarly, there was no significant difference between the patients with oily and non-oily facial skin in terms of the count of noninflammatory acne lesions (p = 0.27). For the count of inflammatory lesions, however, azelaic gel with alcoholic base was significantly more effective than azelaic gel with alcohol-free base in patients with oily facial skin (p = 0.02) (Fig. 3).

DISCUSSION

The first line in treating mild-to-moderate acne vulgaris is using topical medications. Antibiotics play a pivotal role in this regard. However, emerging bacterial resistance has dramatically limited their liberal use in acne vulgaris (Bojar et al., 1993; Simpson, 2001; Bettoli et al., 2006). In the present work, efficacy of 10% azelaic gel with hydro-alcoholic or alcohol-free base was examined in patients with mild-to-moderate acne vulgaris. Accordingly, both preparations were similarly effective against inflammatory and noninflammatory acne lesions (Fig. 1 and 2). This is line with results of previous studies that showed high efficacy of 20% azelaic gel in acne vulgaris (Fitton and Goa, 1991; Graupe et al., 1996; Gollnick et al., 2001; Iraji et al., 2007). Gupta and Gover (2007) also reported effectiveness of 15% azelaic gel in treating facial inflammatory lesions. To the best of our knowledge, however, this is the first study that examined the efficacy of 10% azelaic gel in these patients. Pazoki-Toroudi et al. (2010) showed that combination of 5% azelaic and 2% erythromycin gels is as effective as a combination of 20% azelaic and 2% erythromycin gels in treating mild-to-moderate acne vulgaris. According to the results of the present study, however, 10% azelaic acid gel can be effectively used alone in such patients. Thiboutot (2008) showed that 10% azelaic acid is as effective as benzoyl peroxide in acne patients. They concluded that due to higher satisfactions of patients toward azelaic acid, it is superior to similar medications. All the patients in the present study were also completely satisfied with the results of their treatment. This is also in conformity with the results of another study by Gollnick and Krautheim (2003) that concluded many anti-acne medications can be replaced by azelaic acid. Lack of bacterial resistance against this medication was another suggested preference of azelaic acid over similar medications in this report. Furthermore, unlike many famous ant-acne medications, azelaic acid is safe in pregnant and lactating patients (Fluhr and Degitz, 2010). In the present work, there was not a significant difference between azelaic acid with hydro-alcoholic or alcohol-free base against acne lesions. However, the medication with hydro-alcoholic base was significantly more effective against inflammatory lesions in patients with oily skin. This difference may be attributed to pharmacodynamic specifications or the ability of medication in solving oily layer of the skin in patients with oily skin and hence, more facilitated access to inflammatory lesions, which are more frequent in such patients comparing with those with normal or dry skin type (Khodaeiani et al., 2012). Finally, both medications were along with minor complications, i.e., mild itching in the site of application only in 2.5 and 5% of the patients in two groups. Significant complications have been reported as the major source of patient=s non-adherence to any medication, particularly in young patients with acne vulgaris (Khodaeiani et al., 2013).

CONCLUSION

Both 10% azelaic gels with hydro-alcoholic and alcohol-free bases are comparably effective against mild-to-moderate acne vulgaris. In patients with oily skin, however, 10% azelaic acid with hydro-alcoholic base is superior to the medication with alcohol-free base in patients with oily skin.