*2.7. The Economic Impact of Childhood Obesity*

A search in Pubmed found 264 articles published between 2001 and 2021 on the economic evaluation of prevention and treatment of childhood obesity and overweight. Out of them, 57 are cost-effectiveness studies of interventions aimed at reducing high BP among children and adolescents, or protocols for planned interventions with no results [144].

Two of the studies evaluated interventions to reduce obesity/overweight [145] and promote PA [146]. BP reduction was in both studies a secondary outcome. The Children's Health Interventional Trial was an 11-month outpatient multidisciplinary family-based program implemented with 248 children with obesity or overweight in Germany [145]. The main focus was reducing weight, but the secondary objectives was the improvement of obesity-related health parameters as BP. The intervention obtained a reduction of systolic blood pressure (SBP) by −1.76 mmHg and diastolic blood pressure (DBP) by −2.82 mmHg. The program was cost-effective: on an aggregated level, future savings amounted to between €1859 and €1926 per person, and the return on investment was between 3.3% and 7.0%.

A school-based intervention study evaluated the effect of reduced salt intake among children and their families in China [147]. The focus was on BP of adults in the household rather than children. The intervention was very effective in lowering SBP in adults (−2.3 mmHg), but also in children, and even more in adults older than 60 years (−9.5 mmHg). It was also cost-effective (around \$1358 per QALY [Quality adjusted life years] gained). Another study evaluated the cost-effectiveness of an early nutrition program—supplementing infant formula with long-chain polyunsaturated fatty acids—on health consequences in adulthood, more specifically high BP and the risk of HTN-related diseases in later life. The study results showed that the program is dominant (cost saving); it increases life expectancy by 1.2 QALY, with an incremental cost-effectiveness ratio (discounted to present value) of—€630.

Two of the most relevant studies perform an economic evaluation of screening and BP measuring of children and adolescents. The first one [148] compares costs and effectiveness of BP screening programs for adolescents in the US with population-wide preventive interventions, as reductions in salt intake or increasing physical education. Finding and treating the adolescents at highest risk (e.g., left ventricular hypertrophy) is the most costeffective screening strategy with cost per QALY of \$18,000 for boys and \$47,000 for girls. Universal screening of all adolescents is dominated by specific population-wide strategies such as salt reduction (cost-saving [boys] and \$650/QALY [girls]) and increasing physical education (\$11,000/QALY [boys] and \$35,000/QALY [girls]).

The second study [149] is a retrospective one that evaluated the initial use of ambulatory BP pressure monitoring for children with clinic BP measurements suggesting stage 1 HTN. It concludes that it is highly cost-effective (cost-savings in the long term of \$2.4 million per 1000 patients).

In summary, the evidence so far has shown that some targeted interventions to prevent obesity and high BP in children and adolescents are potentially highly cost-effective.
