This section describes efficacy outcomes from the published literature that the committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the interventional procedure overview.
4.1 In a randomised controlled trial (RCT) of 120 patients who had active or sham microwave ablation for severe primary axillary hyperhidrosis, the proportion of patients with an Hyperhidrosis Disease Severity Scale (HDSS) score of 1 or 2 (unnoticeable or tolerable sweating) was 89% (72/81) and 54% (21/39) respectively at 30‑day follow-up (p<0.001). At 6‑month follow-up, 67% and 44% had an HDSS score of 1 or 2 (p=0.02) respectively. In the active treatment group, 69% of patients had an HDSS score of 1 or 2 at the 9‑month and 12‑month follow-up. The proportion of patients with an HDSS score reduced by 2 or more at 6‑month follow-up was 47% in the active treatment group and 13% in the sham group (p<0.001). The proportion of patients, who had active treatment, with an HDSS score reduced by 2 or more at the 9- and 12‑month follow-up was 42% and 38% respectively. In a case series of 20 patients, the mean reduction in HDSS score at a mean follow-up of 5 months was 2 (95% [confidence interval] CI 1.85 to 2.15, p<0.0001), and 95% (19/20) had an HDSS score of 2 or lower. In a case series of 31 patients, 90% (28/31) of patients had HDSS scores of 1 or 2 at 12‑month follow-up; 94% (29/31) of patients had at least a 1‑point drop and 55% (17/31) had a drop of 2 or more points in HDSS.
4.2 In the RCT of 120 patients who had active or sham microwave ablation, the proportion of patients with a 50% or more reduction in weighed sweat compared with baseline was 80% and 67% respectively at 30‑day follow-up (p=0.07), and 63% and 59% (p=0.69) respectively at 6‑month follow-up. The proportion of patients with a 75% or more reduction was 62% in the active group and 39% in the sham group (p=0.01) at 30‑day follow-up, and 41% and 36% (p=0.60) respectively at 6‑month follow-up. In the case series of 31 patients, 90% (28/31) of patients had at least a 50% reduction in axillary sweat from baseline at 30‑day follow-up.
4.3 In the case series of 31 patients, 85% (23/31) had an improvement of at least 5 points on the Dermatologic Life Quality Index (score ranges from 0 to 30 with higher scores indicating poorer quality of life) at 12‑month follow-up.
4.4 In the case series of 31 patients, 90% (27/30), 96% (27/28), 93% (25/27) and 89% (23/26) of patients were very or somewhat satisfied after 30 days, 3 months, 6 months and 12 months respectively. In the case series of 20 patients, all patients stated that they would have the treatment again.
4.5 The specialist adviser listed the key efficacy outcomes as dryness (measured by the HDSS), and improved quality of life (number of episodes of bothersome sweating per week).