START (STrAtegies for RelaTives) study: a pragmatic randomised controlled trial to determine the clinical effectiveness and cost-effectiveness of a manual-based coping strategy programme in promoting the mental health of carers of people with dementia

Two-thirds of people with dementia live at home, receiving most care from family carers, about 40% of whom have clinically significant depression or anxiety. This impacts on the person with dementia, families and society, predicting care breakdown. There are currently no clinically effective and cost-effective NHS family carer interventions. To assess the STrAtegies for RelaTives (START) intervention in the short (4 and 8 months) and long term (1 and 2 years) compared with treatment as usual (TAU). Randomised, parallel-group, superiority trial with blinded assessment recruiting participants 2:1 (intervention to TAU) to allow for therapist clustering. Three UK mental health services and one neurological service. Family carers of people with dementia. Eight-session manual-based coping intervention delivered by supervised psychology graduates to individuals. Affective symptoms [Hospital Anxiety and Depression Scale-total (HADS-T)] and cost-effectiveness. Secondary measures: anxiety and depression symptoms and caseness, quality of life (QoL), abusive behaviour and long-term care home admission. Two hundred and sixty participants were randomised (173 intervention, 87 TAU). We used intention-to-treat analysis in the short term (152 intervention, 77 TAU) and in the long term (140 intervention, 69 TAU). In the short term, the intervention group had lower HADS-T [mean difference -1.80, 95% confidence interval (CI) -3.29 to -0.31; p=0.02] and higher quality-adjusted life-years (QALYs) (mean difference 0.03, 95% CI -0.01 to 0.08). Costs were no different between groups [mean £ 252 (95% CI -£ 28 to £ 565) for intervention group]. The cost-effectiveness acceptability curve showed a greater than 99% chance of being cost-effectiveness at a £ 30,000/QALY willingness-to-pay threshold and a high probability of cost-effectiveness based on the HADS-T score. Carers in the intervention group had less case-level depression [odds ratio (OR) 0.24, 95% CI 0.07 to 0.76], a trend towards reduced case-level anxiety (OR 0.30, 95% CI 0.08 to 1.05), lower Hospital Anxiety and Depression Scale-anxiety (HADS-A) (-0.91, 95% CI -1.76 to -0.07; p = 0.03) and Hospital Anxiety and Depression Scale-depression (HADS-D) (-0.91, 95% CI -1.71 to -0.10; p = 0.03) and higher Health Status Questionnaire (HSQ) QoL (mean difference 4.09, 95% CI 0.34 to 7.83). Group differences in abusive behaviour (OR 0.48, 95% CI 0.18 to 1.27) and the person with dementia's quality of life-Alzheimer's disease (QoL-AD) (