Background Improving Access to Psychological Therapies (IAPT) is a new programme designed to reduce disease burden to the individual and economic burden to the society of common mental health problems (CMHP). This is the first study to look at the impact of IAPT on health service utilisation and sickness absence using routine data.

Method The authors used pseudonymised secure and privately linked (SAPREL) routinely collected primary, secondary care and clinic computer data from two pilot localities. The authors explored antidepressant prescribing, accident and emergency and outpatients attendances, inpatient stays, bed days, and sick certification. The authors compared the registered population with those with CMHP. The authors then made a 6 months before and after comparison of people referred to IAPT with age–sex and practice-matched controls.

Results People with CMHP used more health resources than those without CMHP: more prescriptions of antidepressants 5.25 (95% CI 5.38 to 5.13), inpatient episodes 4.89 (95% CI 5.0 to 4.79), occupied bed days 1.25 (95% CI 0.95 to 1.55), outpatient 1.5 (95% CI 1.40 to 1.63) and emergency department attendances 0.34 (95% CI 0.31 to 0.37), and medical certificates 0.29 (95% CI 0.26 to 0.32). Comparison of service utilisation 6 months before and after referral to IAPT was associated with reduced use of emergency department attendances (mean difference: 0.12 (95% CI 0.06 to 0.19, p<0.001)). However, the number of prescriptions of antidepressants increased mean difference −0.15 (95% CI 0.02−0.29, p=0.028).

Conclusions People with CMHP use more healthcare resources. Referral to the IAPT programme is associated with a subsequent reduction in emergency department attendances, sickness certification and improved adherence to drug treatment.