Study Overview: New Stroke Therapy for Infants and Toddlers Shows Promise

A new treatment strategy for infants and toddlers who have experienced a stroke has demonstrated improved function and increased skill acquisition. This innovative treatment combines restricting the use of the stronger arm and hand with high-dosage, goal-directed therapy.

The findings are based on a Phase 3 randomized clinical trial that included 167 stroke survivors under the age of three, all presenting with notable impairment in one arm's use.

The children were randomly assigned to one of three treatment groups: a high dose of the new therapy, a moderate dose of the same therapy, or a continuation of their usual care. Six months following treatment, children who received the high-dose version of the specialized therapy, known as I-ACQUIRE, exhibited greater gains in skills and daily function compared to those in the moderate-dose or usual care groups.

Perinatal Stroke and Treatment Approach

Perinatal arterial ischemic stroke (PAIS), the most prevalent form of stroke in children, leads to functional impairment and limited motor control on one side of the body, a condition termed hemiparesis.

The I-ACQUIRE treatment is an adaptation of Constraint-induced Movement Therapy (CIMT). CIMT is a rehabilitation method designed to enhance the use of an impaired upper extremity. The I-ACQUIRE approach specifically for very young children following a stroke aims to increase the use of the more-affected arm and hand. It integrates intensive, task-oriented motor therapy with learning principles to improve motor function, coordination, and independence in daily activities. This is achieved by restricting the stronger arm and hand with a lightweight cast.

This study marks the first evaluation of this CIMT form delivered in the child's home or natural settings, including a parent program.

Dr. Sharon Ramey, a co-director at the Fralin Biomedical Research Institute Neuromotor Research Clinic, stated that this research addresses a gap in knowledge. She noted that previous treatment recommendations relied on data from older children with cerebral palsy and hemiparesis, lacking specific benefits for infants and toddlers. The study now provides data confirming the treatment's reception, safety, and measurable benefits at both dosages.

Treatment Groups and Outcomes

Initially, 216 children, aged 8 to 36 months, were enrolled across 15 U.S. university and hospital sites, with outcomes from 167 children included in the presentation. The treatment groups were structured as follows:

• Moderate-dose I-ACQUIRE therapy: Three hours of therapy per day, combined with constraint of the less-affected limb, five days a week for four consecutive weeks.
• High-dose I-ACQUIRE therapy: Six hours of therapy with constraint of the less-affected arm and hand, five days a week for four consecutive weeks.
• Usual care: Approximately one hour of physical therapy and one hour of occupational therapy each week, typically from community therapists.

Certified assessors, who were blinded to the treatment groups, measured each child's arm and hand skills before, immediately after, and six months post-treatment. Parents also provided ratings of their child's functional performance in daily home activities.

Key Findings

• End of Treatment: Both I-ACQUIRE dose groups showed improvements in neuromotor skills, with a median gain of 3 new skills each (mean gain of 2.94 for moderate dose and 3.30 for high dose), which was significantly higher than the usual care group's median gain of 1 skill. These gains were observed to be smaller than initially anticipated.

• Six Months Post-Treatment: Children in the high-dose group achieved significantly larger skill gains than those in the moderate-dose or usual care groups. These differences were more pronounced for children who adhered closely to the therapy protocol.

• Parent Ratings: Parents in both the high and moderate-dose I-ACQUIRE groups reported meaningful improvements in their children's everyday functional use of their weaker arm and hand. These included skills such as exploring toys, communication gestures, and various self-help activities not previously possible.

• Usual Care Group Observations: Unexpectedly, children in the usual care group also demonstrated clinically important improvements in arm and hand skills at six months, including actions like reaching, grasping, and using the impaired arm for balance. However, parent ratings for this group did not indicate real-world improvements in daily limb use at either the end of treatment or six months later.

Discussion and Limitations

The smaller-than-expected skill gains from I-ACQUIRE therapy may suggest varying responses to treatment among children with PAIS. Dr. Ramey indicated that identifying which children benefit most or least will be crucial. The potential for infants to recover from early stroke is considered to be greater than previously believed, with parents reporting improvements exceeding initial prognoses.

Study strengths included:

• Careful conduct.
• Effective adherence to the treatment plan by families and clinicians.
• A focus on a young population not specifically examined in prior research.

Limitations included:

• Non-representative site selection.
• A reduced final sample size of 167 children due to some unconfirmed PAIS diagnoses.