JMIR Publications

ABSTRACT

Background Evidence suggests that smartphone apps can be effective in the self-management of weight. Given the low cost, broad reach, and apparent effectiveness of apps at promoting weight loss, governments may seek to encourage the uptake of such apps as an opportunity for reducing excess weight among the population. However, the cost and potential cost-effectiveness are important considerations. Our study used a modeling approach to assess the health impacts, health system costs, cost-effectiveness, and health equity of a mass media campaign to promote high quality smartphone apps for weight loss in New Zealand. Methods We used an established proportional multistate life table model that simulates the 2011 New Zealand (NZ) adult population over the lifetime, sub-grouped by age, sex, and ethnicity (Māori [Indigenous]/non-Māori). The key risk factor was BMI. The model compared business-as-usual to a one-off mass media campaign intervention, which included the pooled effect size from a recent meta-analysis of smartphone weight loss apps. The resulting impact on BMI and BMI-related diseases was captured through changes in health gain (quality-adjusted life years; QALYs) and in health system costs (health system perspective). The difference in total health system costs was the net sum of interventions costs and downstream cost offsets due to altered disease rates. A discount rate of 3% was applied to health gains and health system costs. Multiple scenario and sensitivity analyses were also conducted, including an equity adjustment. Results Across the remaining lifetime of the modeled 2011 NZ population, the mass media campaign to promote weight loss apps usage had an estimated overall health gain of 181 (95% uncertainty interval [UI]: 113, 270) QALYs and health care costs of NZ$ -606,000 (95%UI: -2,540,000, 907,000). The mean health care costs were negative, representing an overall savings to the health system and a likely cost-saving intervention. Across the outcomes examined in this study, the modeled mass media campaign to promote weight loss apps among the general population would be expected to provide higher per capita health gain for Māori and hence reduce health inequalities arising from high BMI. Conclusions A modeled mass media campaign to encourage the adoption of smartphone apps to promote weight loss among the NZ adult population is expected to yield an overall gain in health and to be cost-saving to the health system. While other interventions in the nutrition and physical activity space are even more beneficial to health and produce larger cost-savings (eg, fiscal policies, food reformulation), governments may choose to include strategies to promote health app usage as complementary measures.