Lifestyle changes can effectively prevent diabetes onset in individuals with prediabetes. Although nurse-led interventions have proven to be cost-effective and feasible in the management of diabetes and hypertension in primary care, low-intensity lifestyle interventions for people with prediabetes led by nurses remain poorly evaluated.

To assess whether a low-intensity nurse-led telephone lifestyle intervention is effective in reducing fasting plasma glucose levels in individuals with prediabetes.

A two-arm, parallel, randomized controlled clinical.

Five Primary Care Centres in the Balearic Islands, Spain.

A total of 206 participants were enrolled, 103 in each group.

Consenting participants aged 25–75 years, with fasting plasma glucose levels of 100–125 mg/dL, and body mass index ≥ 27 and < 40 kg/m2 were randomly assigned (1:1) to either a 9-month nurse-led telephone lifestyle intervention (intervention) or short text messages with general lifestyle advice (control). Research staff and the statistician were masked to group allocation. The primary outcome was fasting plasma glucose at 9-month follow-up, analyzed per protocol and by intention-to-treat.

Among the 206 participants (103 in each group), 189 (91·8 %; n = 91 in the intervention group, n = 98 in the control group) completed the 4-month follow-up and 181 (87·9 %; n = 87 in the intervention group, n = 94 in the control group) completed the 9-month follow-up. Among the 206 randomized participants, 52.9 % were women, 73.8 % were obese, and 69.4 % were of Spanish nationality. Differences in fasting plasma glucose between groups at 9-months were not statistically significant (Intervention group n = 85 mean 103·4 mg/dL [SD 9·6] vs Control group n = 91 mean 104·8 mg/dL [SD 9·7]; adjusted mean difference 1·1 mg/dL [95 % CI -1·6 to 3·8]; p-value = 0·43). Difference in waist circumference at 9 months were statistically significant (Intervention group n = 85 mean 100.6 cm [SD 10.2] vs Control group n = 91 mean 104.0 cm [SD 10.2]; adjusted mean difference 1.9 cm [95 % CI 0.6 to 3.3]; p-value < 0.01). At 9-month follow-up, diet quality improved in the intervention group (intervention group n = 86 mean 8.4 points [SD 2.0] vs control group n = 93 mean 7.5 points [SD 2.1], adjusted mean difference − 1.3 points [95 CI -1.7 to − 0.7]; p-value < 0.01). Likewise, sedentary behavior presented statistically significant differences at 9-month follow-up (intervention group n = 86 mean 5.4 H/d [SD 1.8] vs control group n = 93 mean 6.3 H/d [SD 1.9], adjusted mean difference 1.0 H/d [95 CI 0.5 to 1.4]; p-value < 0.01).

These results do not support the effectiveness of a low-intensity nurse-led telephone lifestyle intervention in reducing fasting plasma glucose in individuals with prediabetes, although changes in diet quality and sedentary behavior were observed.

Tweetable abstract: A nurse-led phone intervention had no significant benefits on glucose levels in patients with prediabetes. @GlobalHealth_rg.