The importance of long-term follow-up in child and adolescent obesity prevention interventions

Pediatric overweight and obesity continues to be a major public health concern. Once established it is diffi cult to treat; therefore well-designed and evaluated prevention interventions are vitally important. There is considerable evidence to suggest that obesity prevention initiatives can change children ’ s behaviours and weight status over the short- or mediumterm; however, there is far less evidence on which to judge the impact over the longer term. In response to the rise in short- and medium-term obesity prevention studies for children and adolescents over recent years, the Prevention Stream of the Australasian Child and Adolescent Obesity Research Network highlight fi ve points as to why the dearth of obesity prevention studies with long-term follow-up should be urgently addressed. Furthermore, recommendations to strengthen the evidence base and outline key implications for research design in this area and the support required for long-term follow-up studies are detailed.

Randomized controlled trial of a telephone-based intervention for child fruit and vegetable intake: long-term follow-up

Telephone-based interventions can be effective in increasing child fruit and vegetable intake in the short term (<6 mo). The long-term efficacy of such interventions, however, is unknown.

Six year follow-up of students who participated in a school-based physical activity interventions : a longitudinal cohort study

Background
The purpose of this paper was to evaluate the long-term impact of a childhood motor skill intervention on adolescent motor skills and physical activity.

Methods
In 2006, we undertook a follow-up of motor skill proficiency (catch, kick, throw, vertical jump, side gallop) and physical activity in adolescents who had participated in a one-year primary school intervention Move It Groove It (MIGI) in 2000. Logistic regression models were analysed for each skill to determine whether the probability of children in the intervention group achieving mastery or near mastery was either maintained or had increased in subsequent years, relative to controls. In these models the main predictor variable was intervention status, with adjustment for gender, grade, and skill level in 2000. A general linear model, controlling for gender and grade, examined whether former intervention students spent more time in moderate-to-vigorous physical activity at follow-up than control students.

Results
Half (52%, n = 481) of the 928 MIGI participants were located in 28 schools, with 276 (57%) assessed. 52% were female, 58% in Grade 10, 40% in Grade 11 and 54% were former intervention students. At follow-up, intervention students had improved their catch ability relative to controls and were five times more likely to be able to catch: ORcatch = 5.51, CI (1.95 – 15.55), but had lost their advantage in the throw and kick: ORthrow = .43, CI (.23 – .82), ORkick = .39, CI (.20 – .78). For the other skills, intervention students appeared to maintain their advantage: ORjump = 1.14, CI (.56 – 2.34), ORgallop = 1.24, CI (.55 – 2.79). Intervention students were no more active at follow-up.

Conclusion
Six years after the 12-month MIGI intervention, whilst intervention students had increased their advantage relative to controls in one skill, and appeared to maintain their advantage in two, they lost their advantage in two skills and were no more active than controls at follow up. More longitudinal research is needed to explore whether gains in motor skill proficiency in children can be sustained and to determine the intervention characteristics that translate to subsequent physical activity.

Three year follow-up of an early childhood intervention : is movement skill sustained?

Background
Movement skill competence (e.g. the ability to throw, run and kick) is a potentially important physical activity determinant. However, little is known about the long-term impact of interventions to improve movement skills in early childhood. This study aimed to determine whether intervention preschool children were still more skill proficient than controls three years after a 10 month movement skill focused intervention: ‘Tooty Fruity Vegie in Preschools’.

Methods
Children from 18 intervention and 13 control preschools in NSW, Australia were assessed at ages four (Time1), five (T2) and eight years (T3) for locomotor (run, gallop, hop, leap, horizontal jump, slide) and object control proficiency (strike, bounce, catch, kick, overhand throw, underhand roll) using the Test of Gross Motor Development-2. Multi-level object control and locomotor regression models were fitted with variables time, intervention (yes/no) and a time*intervention interaction. Both models added sex of child and retained if significant, in which case interactions of sex of child with other variables were modelled and retained. SPSS (Version 17.0) was used.

Results
Overall follow-up rate was 29% (163/560). Of the 137 students used in the regression models, 53% were female (n = 73). Intervention girls maintained their object control skill advantage in comparison to controls at T3 (p = .002), but intervention boys did not (p = .591). At T3, there were no longer intervention/control differences in locomotor skill (p = .801).

Conclusion
Early childhood settings should implement movement skill interventions and more intensively target girls and object control skills.

Attendance at cardiac rehabilitation is associated with lower all-cause mortality after 14 years of follow-up

Objective To investigate whether attendance at cardiac rehabilitation (CR) independently predicts all-cause mortality over 14 years and whether there is a dose–response relationship between the proportion of CR sessions attended and long-term mortality.

Design Retrospective cohort study.

Setting CR programmes in Victoria, Australia

Patients The sample comprised 544 men and women eligible for CR following myocardial infarction, coronary artery bypass surgery or percutaneous interventions. Participants were tracked 4 months after hospital discharge to ascertain CR attendance status.

Main outcome measures All-cause mortality at 14 years ascertained through linkage to the Australian National Death Index.

Results In total, 281 (52%) men and women attended at least one CR session. There were few significant differences between non-attenders and attenders. After adjustment for age, sex, diagnosis, employment, diabetes and family history, the mortality risk for non-attenders was 58% greater than for attenders (HR=1.58, 95% CI 1.16 to 2.15). Participants who attended <25% of sessions had a mortality risk more than twice that of participants attending ≥75% of sessions (OR=2.57, 95% CI 1.04 to 6.38). This association was attenuated after adjusting for current smoking (OR=2.06, 95% CI 0.80 to 5.29).

Conclusions This study provides further evidence for the long-term benefits of CR in a contemporary, heterogeneous population. While a dose–response relationship may exist between the number of sessions attended and long-term mortality, this relationship does not occur independently of smoking differences. CR practitioners should encourage smokers to attend CR and provide support for smoking cessation.

Is cost effectiveness sustained after weekend inpatient rehabilitation? 12 month follow up from a randomized controlled trial

BACKGROUND: Our previous work showed that providing additional rehabilitation on a Saturday was cost effective in the short term from the perspective of the health service provider. This study aimed to evaluate if providing additional rehabilitation on a Saturday was cost effective at 12 months, from a health system perspective inclusive of private costs. METHODS: Cost effectiveness analyses alongside a single-blinded randomized controlled trial with 12 months follow up inclusive of informal care. Participants were adults admitted to two publicly funded inpatient rehabilitation facilities. The control group received usual care rehabilitation services from Monday to Friday and the intervention group received usual care plus additional Saturday rehabilitation. Incremental cost effectiveness ratios were reported as cost per quality adjusted life year (QALY) gained and for a minimal clinical important difference (MCID) in functional independence. RESULTS: A total of 996 patients [mean age 74 years (SD 13)] were randomly assigned to the intervention (n = 496) or control group (n = 500). The intervention was associated with improvements in QALY and MCID in function, as well as a non-significant reduction in cost from admission to 12 months (mean difference (MD) AUD$6,325; 95% CI -4,081 to 16,730; t test p = 0.23 and MWU p = 0.06), and a significant reduction in cost from admission to 6 months (MD AUD$6,445; 95% CI 3,368 to 9,522; t test p = 0.04 and MWU p = 0.01). There is a high degree of certainty that providing additional rehabilitation services on Saturday is cost effective. Sensitivity analyses varying the cost of informal carers and self-reported health service utilization, favored the intervention. CONCLUSIONS: From a health system perspective inclusive of private costs the provision of additional Saturday rehabilitation for inpatients is likely to have sustained cost savings per QALY gained and for a MCID in functional independence, for the inpatient stay and 12 months following discharge, without a cost shift into the community. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry November 2009 ACTRN12609000973213 .

Overweight and obesity from childhood to adulthood: a follow-up of participants in the 1985 Australian Schools Health and Fitness Survey

Objective: To examine overweight and obesity in Australian children followed through to adulthood.

Design and participants: A cohort study of 8498 children aged 7–15 years who participated in the 1985 Australian Schools Health and Fitness Survey; of these, 2208 men and 2363 women completed a follow-up questionnaire at age 24–34 years in 2001–2005.

Main outcome measures: Height and weight were measured in 1985, and self-reported at follow-up. The accuracy of self-reported data was checked in 1185 participants. Overweight and obesity in childhood were defined according to international standard definitions for body mass index (BMI), and, in adulthood, as a BMI of 25–29.9 and ≥ 30 kg/m2, respectively, after correcting for self-report error.

Results: In those with baseline and follow-up data, the prevalence of overweight and obesity in childhood was 8.3% and 1.5% in boys and 9.7% and 1.4% in girls, respectively. At follow-up, the prevalence was 40.1% and 13.0% in men and 19.7% and 11.7% in women. The relative risk (RR) of becoming an obese adult was significantly greater for those who had been obese as children compared with those who had been a healthy weight (RR = 4.7; 95% CI, 3.0–7.2 for boys and RR = 9.2; 95% CI, 6.9–12.3 for girls). The proportion of adult obesity attributable to childhood obesity was 6.4% in males and 12.6% in females.

Conclusion: Obesity in childhood was strongly predictive of obesity in early adulthood, but most obese young adults were a healthy weight as children.

The skeletal benefits of calcium- and vitamin D3-fortified milk are sustained in older men after withdrawal of supplementation: an 18 mo follow-up study

Background: In a previous 2-y randomized controlled trial, we showed that calcium- and vitamin D₃–fortified milk stopped or slowed bone loss at several clinically relevant skeletal sites in older men.

Objective: The present study aimed to determine whether the skeletal benefits of the fortified milk were sustained after withdrawal of the supplementation.

Design: One hundred nine men >50 y old who had completed a 2-y fortified milk trial were followed for an additional 18 mo, during which no fortified milk was provided. Bone mineral density (BMD) of the total hip, femoral neck, lumbar spine, and forearm was measured by using dual-energy X-ray absorptiometry.

Results: Comparison of the mean changes from baseline between the groups (adjusted for baseline age, BMD, total calcium intake, and change in weight) showed that the net beneficial effects of fortified milk on femoral neck and ultradistal radius BMD at the end of the intervention (1.8% and 1.5%, respectively; P < 0.01 for both) were sustained at 18-mo follow-up (P < 0.05 for both). The nonsignificant between-group differences at the total hip (0.8%; P = 0.17) also persisted at follow-up (0.7%; P = 0.10), but there were no lasting benefits at the lumbar spine. The average total dietary calcium intake in the milk supplementation group at follow-up approximated recommended amounts for Australian men >50 y old (1000 mg/d) but did not differ significantly from that in the control subjects (1021 versus 890 mg/d).

Conclusion: Supplementation with calcium- and vitamin D₃–fortified milk for 2 y may provide some sustained benefits for BMD in older men after withdrawal of supplementation.