What is the efficacy of emollients (ingredient of a moisturiser) and moisturisers for eczema?
Eczema is a chronic skin disorder, the main symptoms being dry skin and intense itching. Skin lesions include redness, crusts, scratches, and oozing. Moisturisers are a cornerstone of eczema treatment, but there is uncertainty about their efficacy and whether one moisturiser is preferable to another.
We reviewed 77 studies (up to December 2015), including 6603 people with mainly mild to moderate eczema. Age varied between four months and 84 years (mean: 18.6 years). There were slightly more women than men. Most studies lasted between two to six weeks, with a few lasting six months.
Of the 77 studies, 46 were funded predominantly by pharmaceutical companies.
Most moisturisers appeared to be effective. Almost a third of the studies reported how people assessed their eczema. Only 13 assessed satisfaction with the moisturiser. Side effects were reported in 41 studies, although this information was often limited (mainly smarting, stinging, itch, redness). The studies mostly evaluated physician-assessed eczema severity (65 studies). Other outcomes addressed were skin barrier function (29 studies), flare prevention (16), quality of life (10), and corticosteroid use (8).
According to the physicians, moisturisers reduced eczema severity compared with no moisturiser (three studies), but the reduction was too small to be considered important enough for a patient. There were fewer flares (two studies) and less topical corticosteroids were needed (two studies). Participant-assessed eczema severity and satisfaction were not evaluated. There was no difference in the number of adverse events reported.
Participants thought Atopiclair (containing glycyrrhetinic acid) was over four times more effective in improving eczema-severity than the vehicle, i.e. carrier (three studies). However, the physicians did not find a difference considered important enough for a patient. Atopiclair led to greater reduction of itch (four studies), more frequent satisfaction (two studies), and fewer flares (three studies). The number of reported adverse events was similar in each group.
Four studies evaluated urea-containing cream. Participants using urea reported skin improvement more often than those using placebo (one study). Satisfaction ratings were comparably positive between the two groups (one study). Urea-containing cream improved dryness more often (physician assessment) (one study) and led to fewer flares (one study), but more adverse events were reported in this group.
Three studies assessed glycerol-containing moisturiser versus vehicle or placebo. More participants in the glycerol group considered their skin to be improved (one study), as did the physicians, but this was not considered important enough for patients. Participant satisfaction was not addressed. There was no difference in the number of adverse events reported.
Four studies investigated oat-containing moisturisers versus no treatment or vehicle. No differences between groups were observed for participant assessment of improvement (one study), satisfaction (one study), or physician-assessed improvement (three studies). However, fewer flares were reported in the oat group (one study), and less topical corticosteroids were needed (two studies). Oat creams caused more adverse events.
Participants considered moisturisers more than twice as effective in improving eczema than placebo, vehicle, or no moisturiser (five studies) and more effective on itch (seven studies). Participants in both treatment arms reported comparable satisfaction (three studies). According to the physicians, moisturisers decreased eczema severity more than the control (12 studies) and led to fewer flares (six studies). There were no differences between the groups in the number of adverse events reported.
Topical corticosteroids were more effective in improving eczema when used together with a moisturiser, rather than used alone, according to the physicians (three studies) and also reduced the number of flares (one study). The combination was also favoured more by participants. Participant-assessed disease severity was not addressed in this comparison. There was no difference in the number of adverse events reported.
Quality of the evidence
There was high certainty evidence for physician assessments of disease severity comparing glycerol-containing creams to control and 'all moisturisers versus control'. For most other outcomes in the various comparisons, there was low to moderate certainty evidence. The most important reasons for lowering the certainty of evidence were risk of bias in studies (e.g. no blinding, or missing data) or too few participants leading to less precise results.
Most moisturisers showed some beneficial effects, producing better results when used with active treatment, prolonging time to flare, and reducing the number of flares and amount of topical corticosteroids needed to achieve similar reductions in eczema severity. We did not find reliable evidence that one moisturiser is better than another.
Eczema is a chronic skin disease characterised by dry skin, intense itching, inflammatory skin lesions, and a considerable impact on quality of life. Moisturisation is an integral part of treatment, but it is unclear if moisturisers are effective.
To assess the effects of moisturisers for eczema.
We searched the following databases to December 2015: Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, LILACS, the GREAT database. We searched five trials registers and checked references of included and excluded studies for further relevant trials.
Randomised controlled trials in people with eczema.
We used standard Cochrane methodological procedures.
We included 77 studies (6603 participants, mean age: 18.6 years, mean duration: 6.7 weeks). We assessed 36 studies as at a high risk of bias, 34 at unclear risk, and seven at low risk. Twenty-four studies assessed our primary outcome 'participant-assessed disease severity', 13 assessed 'satisfaction', and 41 assessed 'adverse events'. Secondary outcomes included investigator-assessed disease severity (addressed in 65 studies), skin barrier function (29), flare prevention (16), quality of life (10), and corticosteroid use (eight). Adverse events reporting was limited (smarting, stinging, pruritus, erythema, folliculitis).
Six studies evaluated moisturiser versus no moisturiser. 'Participant-assessed disease severity' and 'satisfaction' were not assessed. Moisturiser use yielded lower SCORAD than no moisturiser (three studies, 276 participants, mean difference (MD) -2.42, 95% confidence interval (CI) -4.55 to -0.28), but the minimal important difference (MID) (8.7) was unmet. There were fewer flares with moisturisers (two studies, 87 participants, RR 0.40, 95% CI 0.23 to 0.70), time to flare was prolonged (median: 180 versus 30 days), and less topical corticosteroids were needed (two studies, 222 participants, MD -9.30 g, 95% CI -15.3 to -3.27). There was no statistically significant difference in adverse events (one study, 173 participants, risk ratio (RR) 15.34, 95% CI 0.90 to 261.64). Evidence for these outcomes was low quality.
With Atopiclair (three studies), 174/232 participants experienced improvement in participant-assessed disease severity versus 27/158 allocated to vehicle (RR 4.51, 95% CI 2.19 to 9.29). Atopiclair decreased itching (four studies, 396 participants, MD -2.65, 95% CI -4.21 to -1.09) and achieved more frequent satisfaction (two studies, 248 participants, RR 2.14, 95% CI 1.58 to 2.89), fewer flares (three studies, 397 participants, RR 0.18, 95% CI 0.11 to 0.31), and lower EASI (four studies, 426 participants, MD -4.0, 95% CI -5.42 to -2.57), but MID (6.6) was unmet. The number of participants reporting adverse events was not statistically different (four studies, 430 participants, RR 1.03, 95% CI 0.79 to 1.33). Evidence for these outcomes was moderate quality.
Participants reported skin improvement more frequently with urea-containing cream than placebo (one study, 129 participants, RR 1.28, 95% CI 1.06 to 1.53; low-quality evidence), with equal satisfaction between the two groups (one study, 38 participants, low-quality evidence). Urea-containing cream improved dryness (investigator-assessed) more frequently (one study, 128 participants, RR 1.40, 95% CI 1.14 to 1.71; moderate-quality evidence) with fewer flares (one study, 44 participants, RR 0.47, 95% CI 0.24 to 0.92; low-quality evidence), but more participants in this group reported adverse events (one study, 129 participants, RR 1.65, 95% CI 1.16 to 2.34; moderate-quality evidence).
Three studies assessed glycerol-containing moisturiser versus vehicle or placebo. More participants in the glycerol group noticed skin improvement (one study, 134 participants, RR 1.22, 95% CI 1.01 to 1.48; moderate-quality evidence), and this group saw improved investigator-assessed SCORAD (one study, 249 participants, MD -2.20, 95% CI -3.44 to -0.96; high-quality evidence), but MID was unmet. Participant satisfaction was not addressed. The number of participants reporting adverse events was not statistically significant (two studies, 385 participants, RR 0.90, 95% CI 0.68 to 1.19; moderate-quality evidence).
Four studies investigated oat-containing moisturisers versus no treatment or vehicle. No significant differences between groups were reported for participant-assessed disease severity (one study, 50 participants, RR 1.11, 95% CI 0.84 to 1.46; low-quality evidence), satisfaction (one study, 50 participants, RR 1.06, 95% CI 0.74 to 1.52; very low-quality evidence), and investigator-assessed disease severity (three studies, 272 participants, standardised mean difference (SMD) -0.23, 95% CI -0.66 to 0.21; low-quality evidence). In the oat group, there were fewer flares (one study, 43 participants, RR 0.31, 95% CI 0.12 to 0.7; low-quality evidence) and less topical corticosteroids needed (two studies, 222 participants, MD -9.30g, 95% CI 15.3 to -3.27; low-quality evidence), but more adverse events were reported (one study, 173 participants; Peto odds ratio (OR) 7.26, 95% CI 1.76 to 29.92; low-quality evidence).
All moisturisers above were compared to placebo, vehicle, or no moisturiser. Participants considered moisturisers more effective in reducing eczema (five studies, 572 participants, RR 2.46, 95% CI 1.16 to 5.23; low-quality evidence) and itch (seven studies, 749 participants, SMD -1.10, 95% CI -1.83 to -0.38) than control. Participants in both treatment arms reported comparable satisfaction (three studies, 296 participants, RR 1.35, 95% CI 0.77 to 2.26; low-quality evidence). Moisturisers led to lower investigator-assessed disease severity (12 studies, 1281 participants, SMD -1.04, 95% CI -1.57 to -0.51; high-quality evidence) and fewer flares (six studies, 607 participants, RR 0.33, 95% CI 0.17 to 0.62; moderate-quality evidence), but there was no difference in adverse events (10 studies, 1275 participants, RR 1.03, 95% CI 0.82 to 1.30; moderate-quality evidence).
Topical active treatment combined with moisturiser was more effective than active treatment alone in reducing investigator-assessed disease severity (three studies, 192 participants, SMD -0.87, 95% CI -1.17 to -0.57; moderate-quality evidence) and flares (one study, 105 participants, RR 0.43, 95% CI 0.20 to 0.93), and was preferred by participants (both low-quality evidence). There was no statistically significant difference in number of adverse events (one study, 125 participants, RR 0.39, 95% CI 0.13 to 1.19; very low-quality evidence). Participant-assessed disease severity was not addressed.